Practical Surgery (PDF) - Dental Procedures - Maxillary/Mandibular Nerves

Practical Surgery 1 Maxillary Nerve  Maxillary nerve is the second branch of the three divisions of the trigeminal nerve (the fifth {V} cranial nerve)  trigeminal nerve is the largest cranial nerve  Ophthalmic branch is pure sensory  supplies upper third...

Practical Surgery 1 Maxillary Nerve  Maxillary nerve is the second branch of the three divisions of the trigeminal nerve (the fifth {V} cranial nerve)  trigeminal nerve is the largest cranial nerve  Ophthalmic branch is pure sensory  supplies upper third of the face  Maxillary branch is also pure sensory  supplies middle third of the face  Mandibular branch is mixed (has motor root that joins the sensory root)  supplies lower third of the face  It comprises the principal functions of sensation from the maxillary area of the skin of the middle face & maxillary teeth of upper jaw, mucous membranes related to the maxilla, nasal cavity, sinuses, the palate Anatomy & course  Anterior to the trigeminal ganglion {in Meckel's cavity in the middle cranial fossa}, the maxillary nerve passes through the lateral wall of the cavernous sinus and exits the skull through the foramen rotundum & into the pterygopalatine fossa, then continues into the inferior orbital fissure into the infra-orbital groove & infraorbital canal where it terminates in the face into 3 branches (Inferior palpebral / Nasal lateral / Superior labial) Page 1 of 4  Branches of the maxillary nerve 1. In the cranium (cranial cavity) 1) Middle meningeal nerve  supply the meninges (dura mater of middle cranial fossa) 2. From the pterygopalatine fossa 1) 2 ganglionic roots forming the pterygopalatine ganglion {sphenopalatine ganglion} which then gives 5 branches:  Orbital branches  Nasopalatine nerve  supplies palatal mucosa related to anterior teeth  Greater palatine nerve  supplies the hard palate  Lesser palatine nerve  supplies the soft palate  Pharyngeal branch of maxillary nerve 2) Zygomatic nerve through inferior orbital fissure then divides into 2 branches: -  Zygomaticotemporal nerve (communicates with lacrimal nerve & reaches face through zygomaticotemporal foramen)  supplies skin over the anterior temporal region  Zygomaticofacial nerve (reaches face through zygomaticofacial foramen supplies skin over the zygomatic bone (prominence of the cheek) 3) The posterior superior alveolar nerve (or nerves as there maybe be two or three)  Arises from the maxillary nerve in the pterygopalatine fossa  It passes through the pterygomaxillary fissure out into the infratemporal fossa and onto the tuberosity of the maxilla  After sending branches to the upper gum and mucous membrane of the cheek & mucous membrane of maxillary sinus, the nerve enters the maxilla through the posterior superior alveolar foramen (foramina if many) to supply the maxillary molars (main nerve supply for upper molar teeth) 4) Continues as Infraorbital nerve through infraorbital groove & infraorbital canal 3. In the infraorbital canal (as infraorbital nerve)  The infraorbital nerve provides branches that are given off in the floor of the orbit to supply the upper teeth and the lining of the maxillary sinus, these branches are:  Middle superior alveolar nerve  main nerve supply for upper premolars  Anterior superior alveolar nerve  main nerve supply for upper anteriors Page 2 of 4 4. Final branches for sensation on the face 1) Inferior palpebral nerve  supply skin of the lower eyelid 2) Lateral nasal nerve  supply skin over the side/lateral of the nose and the lining of the nasal vestibule 3) Superior labial nerve  supply skin over the cheek, the upper lip and its labial glands, and the lining of the oral vestibule. Page 3 of 4  Nerve Supply for Maxillary teeth Anterior superior alveolar nerve supplies  Pulp, investing structure & labial mucoperiosteum of  Anterior teeth (1/2/3) Middle superior alveolar nerve supplies  Pulp, investing structure & labial mucoperiosteum of  Premolars {4/5} & Mesiobuccal root of 1st molar {6} Posterior superior alveolar nerve supplies  Pulp, investing structure & labial mucoperiosteum of  Upper molars {6/7/8} except Mesiobuccal root of 1st molar {6} Greater (anterior) palatine nerve supplies  Palatal mucoperiosteum of  Maxillary molars {6/7/8} & premolars {4/5) Nasopalatine nerve supplies Palatal mucoperiosteum of  Maxillary anterior teeth {1/2/3} Page 4 of 4  Practical Surgery 2 Mandibular Nerve Definition  It is the 3rd division of the trigeminal nerve {V} Origin  It is a mixed nerve formed of 2 roots:  Sensory root  arises from trigeminal ganglion & runs toward the foramen ovale  Motor root  arises from trigeminal motor nucleus in the pons to join sensory root in foramen ovale Course & relations  The main trunk gives 2 branches then divides into 2 divisions (small anterior & large posterior) about ½ cm below foramen ovale Superior orbital fissure {SOF}  Ophthalmic (V1) F. rotundum  Maxillary (V2) F. ovale  Mandibular (V3) Page 1 of 4  Branches of the mandibular nerve 1. Branches of the main trunk (1 sensory + 1 motor) 1) Nervous spinosus (sensory)  it re-enters the cranial cavity through the foramen spinosum  Supplies dura mater of the middle cranial fossa 2) Nerve to medial pterygoid (motor)  Supplies the muscles medial pterygoid, tensor palati, tensor tympani 2. Branches from the anterior division (3 motor + 1 sensory) (mainly motor) 1) Masseteric nerve (motor)  supplies masseter muscle 2) Nerve to lateral pterygoid (motor)  supplies lateral pterygoid muscles 3) Deep temporal nerve (2 motor nerves)  supplies temporalis muscles 4) Buccal nerve {Long buccal} (sensory)  supplies skin covering the buccinator muscle & mucous membrane of cheek & gums opposite to molar teeth 3. Branches from the posterior division (3 sensory + 1 motor) (mainly sensory) 1) Auriculotemporal nerve (sensory), which arises by 2 roots  Supplies the TMJ, parotid gland, temporal region 2) Lingual nerve (sensory), it passes along a groove in inner surface of the socket of 3rd molar & it caries:  General sensations from floor of mouth & lingual gums  General & taste sensations from anterior 2/3 of tongue  Secretomotor parasympathetic fibers from corda tympani (branch of facial nerve) to submandibular & sublingual gland 3) Inferior alveolar nerve (sensory), the largest branch, it enters mandibular foramen & runs in the mandibular canal supplying the lower molar teeth then ends opposite to mental foramen by dividing into 2 branches  Mental nerve  comes out of mental foramen to supply gingiva opposite to premolar & anterior teeth  Incisive nerve  continues inside mandibular nerve to supply anterior teeth 4) Nerve to mylohyoid (motor), arises as a branch of inferior alveolar nerve before it enters mandibular foramen  Supplies mylohyoid muscle & anterior belly of digastric muscle Page 2 of 4 = motor nerve Page 3 of 4  How to anesthetize mandibular teeth Molar teeth  Inferior alveolar nerve for teeth  Lingual nerve for lingual mucosa  Buccal nerve for buccal mucosa Premolar teeth  Inferior alveolar nerve for teeth  Lingual nerve for lingual mucosa  Mental nerve (branch from inferior alveolar nerve) for buccal mucosa Anterior teeth  Incisive nerve (branch from inferior alveolar nerve) for teeth  Mental nerve (branch from inferior alveolar nerve) for labial mucosa  Lingual nerve for lingual mucosa  Interlacing fibers from opposite side (incisive nerve) Page 4 of 4  Practical Surgery 3 Infection Control in Dental Clinic Why is infection control important in dentistry?  Both patients and dental health care personnel (DHCP) can be exposed to pathogens  Contact with blood, oral and respiratory secretions, and contaminated equipment occurs  Proper procedures can prevent transmission of infections among patients & DHCP Modes of transmission of infection 1) Direct contact with blood or body fluids 2) Indirect contact with a contaminated instrument or surface 3) Contact of mucosa of the eyes, nose, or mouth with droplets or spatter 4) Inhalation of airborne microorganisms  Standard Precautions that are applied to all patients 1. Hand Hygiene 2. Use of gloves, masks, eye protection, and gowns-PPE {personal protective equipment} 3. Sterilization of equipment 4. Aseptic techniques 5. Control infection of environmental surfaces (environmental infection control) 6. Waste management 7. Injury prevention 1. Hand Hygiene (washing hands to remove germs) 1) Wet your hands 2) Use soap (plain or antimicrobial soap)  Using alcohol-based hand rub is the best 3) Lather and scrub for 20 sec (don’t forget to wash between fingers & under nails & the tops of your hands)  no long nails in the clinic as it’s a source of infection 4) Rinse for 10 sec 5) Turn off tap 6) Dry your hands Page 1 of 4 2. Personal Protective Equipment {PPE}  A major component of Standard Precautions  Protects skin & mucous membranes from exposure to infectious materials in spray or spatter  Should be removed when leaving treatment areas Surgical masks, protective eyewear & face shields  Wear a surgical mask & either eye protection with solid side shields or a face shield to protect mucous membranes of the eyes, nose, & mouth Protective Clothing  Wear gowns, lab coats, or uniforms that cover skin & personal clothing likely to become soiled with blood, saliva, or infectious material  Change if visibly soiled  Remove all barriers before leaving the work area Remove hand accessories (Watches, jewelry, rings)  Can tear the gloves  Very difficult to sterilize if infected with blood or saliva Gloves  Reduce contamination of the hands of health care personnel by microbial flora that can be transmitted from one patient to another  Surgical gloves are the last thing to wear before operating on the patient so it doesn’t touch any contaminated surfaces (we don’t do wrapping or disinfection with it)  Wear gloves when contact with blood, saliva, and mucous membranes is possible  Remove gloves after patient care  Wear a new pair of gloves for each patient  Remove gloves that are torn, cut or punctured  Do not wash, disinfect or sterilize gloves for reuse (single use only) Page 2 of 4 3. Sterilization of Equipment Critical Instruments:  Penetrate mucous membranes or contact bone, the bloodstream, or other normally sterile tissues (of the mouth)  Includes  surgical instruments, scalpel blades, periodontal scalers, and surgical dental burs  Autoclaving between uses or use sterile single-use, disposable devices {scalpel blade & needle} Semi-critical  Contact mucous membranes but do not penetrate soft tissue  Includes  Dental mouth mirrors, amalgam condensers, and dental handpieces  Autoclaving or high-level disinfection Non-critical instruments and devices  Contact intact skin  Includes  X-ray heads, facebows, pulse oximeter, blood pressure cuff  Clean and disinfect using a low to intermediate level disinfectant Page 3 of 4 5. Environmental infection control There are 2 categories of Environmental Surfaces (check cleanliness of working area) :- 1) Clinical contact surfaces with High potential for direct contamination from spray or spatter or by contact with DHCP’s gloved hand  Includes  handle of the light, handle of the unit, bracket table, etc…  Cleaning & wrapping 2) Housekeeping surfaces which do not come into contact with patients or devices  Limited risk of disease transmission  May become contaminated and not directly involved in infectious disease transmission  Do not require as stringent {strict} decontamination procedures 6. Medical waste management  Poses a potential risk of infection during handling and disposal  Includes  Sharp instruments (needle, syringe, blade)  Disposed of in the safety box to prevent any injury 7. Injury prevention  Using instruments instead of fingers to retract or palpate tissue  While using the handpiece or giving anesthesia (except in the inferior alveolar nerve block where finger is used to check for landmarks)  One-handed needle recapping Page 4 of 4  Practical Surgery 4 Techniques of Anaesthesia  Armamentarium for Local Anaesthesia 1. Needle 2. Syringe 3. Local Analgesic carpule (cartridge) 4. Auxiliary materials 1. Needle Parts of the needle:  Bevel (part where the solution comes out)  Shaft  Hub  Syringe adaptor  Cartridge-penetrating end Length of needles:  Extra short Needles (15mm)  For PDL injection  Short Needles (20-25mm)  used for infiltration injections  Long Needles (32-40mm)  used for nerve Block injection Diameter / Thickness:  Dental gauge usually 25,27 &30 (the higher the gauge  the thinner the needle)  Gauge 30 has the smallest diameter & the thinnest 2. Syringe According to material:  Metal (most commonly used)  Plastic  Glass According to aspiration:  Aspirating (to check if I’m in a blood vessel)  Non-aspirating Page 1 of 22  Metallic cartride syringe The dental syringe consists of:  Needle adaptor / Threaded hub (holds the needle)  Syringe barrel (holds the cartridge)  Harpoon/hook (if present then it’s an aspirating syringe)  Piston rod / Plunger  Finger grip  Thumb ring Aspirating vs Non-aspirating Aspirating (has a harpoon / hook) Non-aspirating (no hook / flat end) According mode of loading (how we load the carpule in the syringe)  Top loading (not the one we use  Basal loading  Lateral loading Lateral loading Basal loading Page 2 of 22  There’s a special type of pressure syringe for PDL injection, when auxiliary injection is needed  Pressure syringe  used in intraligamentary {IL} injection techniques, especially in mandibular teeth (very important for IL anesthesia to be under high pressure), its types:  Pistol-grip Uses extra short needle with them (15mm)  Pen-grip Pistol-grip Pen-grip 3. Local Analgesic carpule (Cartridge) Local anaesthetic agent  Ester or amide group Vasoconstrictor  Confines anesthetic agent to a localized area increasing the depth & duration of anaesthesia  Less Toxicity as it decreases anaesthetic solution absorption  Provides relatively bloodless field (decrease bleeding)  Prevents haematogenous absorption of local sepsis or pus during surgical procedure Reducing agent  Sodium meta-bisulphite  Prevents the oxidation of the vasoconstrictor especially on prolonged exposure to sunlight (turns into yellow or brown in color became sodium meta-bisuplhate) by taking extra oxygen in solution Fungicide  Thymoral Preservative Vehicle  All components are dissolved in isotonic vehicle “Ringer solution” Page 3 of 22 4. Auxiliary material  For swabbing (remove saliva & food debris) & painting (disinfection)  Cotton applicator to dry area of needle insertion  Aseptic solution (betadine)  Topical anaesthesia  Steps for atraumatic injection technique 1) Use a sterilized sharp needle 2) Check the flow of local anesthetic solution 3) Position the patient 4) Dry the tissue 5) Apply topical antiseptic 6) Apply topical anesthetic 7) Establish a firm hand rest 8) Make the tissue taut (stretched or pulled)  retraction  Gives better vision  The more stretched the tissues  the less pain the patient feels during injection 9) Keep the syringe out of the patient’s line of sight 10) Insert the needle into the mucosa 11) Slowly advance the needle toward the target 12) Aspirate (to make sure I’m not in a blood vessel) 13) Slowly deposit the local anesthetic solution 14) Slowly withdraw the syringe 15) Cap the needle and discard it (must recap with single hand technique)  to prevent injury Page 4 of 22  Types of local anesthesia Topical  Gel or spray  No penetration of tissues Infiltration  For terminal nerve endings Field block  Branches of the main nerve Nerve block  Blocks a well-known main nerve Maxillary Anesthesia Techniques 1. Local infiltration technique (Paraperiosteal or Supraperiosteal)  This technique depends on the diffusion of anesthetic solution through the periosteum and the minute foramina in the cortical plate to reach the nerve endings in cancellous bone Indications 1) Pulpal anesthesia of the maxillary teeth when treatment is limited to one or two teeth 2) Soft tissue anesthesia when indicated for surgical procedures in a circumscribed area Contraindications 1) Infection or acute inflammation in the area of injection  to prevent spreading the infection 2) Dense bone covering the apices of teeth (as in mandibular teeth) Page 5 of 22  Buccal infiltration injection:  A 27 gauge short needle, is mounted in a cartridge syringe which is held in a pen grasp  The needle is inserted with 45-degree angle, and the bevel toward the surface of the bone.  Insert the needle into the height of the muco-buccal fold over the target tooth  depth of the sulcus  Advance the needle until its bevel is at or just above the apical region of the tooth  In most instances the depth of penetration is only a few millimeters because the needle is in soft tissue (slightly touching bone & not preferred to penetrate the periosteum so that the injection isn’t painful to the patient)  there should be no resistance to its advancement, nor should there be any patient discomfort with this injection  The needle is inserted through the mucous membrane & underlying connective tissue until it is gently come in contact with the periosteum (just slight touch)  The solution should be deposited slowly When bevel is toward the bone  we don’t penetrate the periosteum (the soft tissue that delivers blood supply to the bone) If bevel away from the bone  we penetrate the periosteum, the injection is very painful & ballooning occurs (anesthesia collected & make a balloon instead of spreading through the cancellous bone) Page 6 of 22  Palatal infiltration injection: Greater palatine infiltration  The point of the needle insertion is located midway between the cervical margin of the tooth (free gingival margin) to be anesthetized & the midline of the palate (median palatine raphe)  Always inserted distal to the target tooth  to anesthetize the nerve before it reaches the tooth as the greater palatine nerve emerges from the greater palatine foramen that is situated between the 7 & 8, moving postero-anterior (moving from posterior to anterior teeth)  All upper palatal infiltration is distal to the tooth except  Upper third molar {8} where we give mesial to it for 2 reasons:  The greater palatine foramen is between the 7 & 8 (mesial to the 8)  To avoid dissemination of the solution to the lesser palatine nerve at the soft palate & uvula that might cause a gagging reflex  The syringe is held in pen grasp & directed from the other side to be at right angle to the palatal vault with the bevel toward the bone surface Page 7 of 22 2. Greater Palatine Nerve Block  To give a greater palatine nerve block, we need to anesthesia it when it’s still in the greater palatine foramen & not its branches  The greater palatine nerve foramen is situated between the second & third molars & 1cm away from palatal gum margin (free gingival margin) Technique  To block the nerve at this point, a syringe with a short needle is directed from the opposite side of the mouth.  About 0.2 - 0.3 ml of the anesthetic solution should be injected slowly & anterior to this point to avoid dissemination of the solution to the lesser palatine nerve & avoid gagging reflex 3. Nasopalatine / Incisive Nerve Block  Called a nerve block as the injection at the nasopalatine foramen anesthetizes all the 6 anterior teeth at once  This injection will anaesthetize the terminal branches of the long spheno-palatine nerves, which supply the palatal alveolar plate and its overlying mucoperiosteum opposite the six anterior teeth.  The opening of the incisive canal on to the palate is marked by the incisive papilla in the midline, it is one cm posterior to the central incisors  This papilla is very sensitive & such an injection may be painful Page 8 of 22  Technique  A few drops of the anaesthetic solution should be injected initially a little to one side of the papilla  After these have taken effect, the needle is inserted just into the incisive papilla perpendicular on the palate & parallel to the labial surface of the maxillary central incisors  A short needle is used and 0.5 ml of the anesthetic solution is injected very slowly 4. Posterior Superior Alveolar Nerve Block Indications 1) When treatment involves two or more maxillary molars 2) When supraperiosteal injection is contraindicated (e.g., with infection or acute inflammation) 3) When supraperiosteal injection has proved ineffective Contraindication 1) When the risk of hemorrhage is too great Page 9 of 22  Technique  Pull the tissues at the injection site taut (firm taut reflection)  Insert the needle into the height of the muco-buccal fold (depth of sulcus) over the upper 7  Advance the needle slowly in an upward, inward, and backward direction in one movement (not three different movements)  Upward: superiorly at a 45-degree angle to the occlusal plane.  Inward: medially toward the midline at a 45-degree angle to the occlusal plane  Backward: posteriorly at a 45-degree angle to the long axis of the second molar  Using “long” dental needle (>32 mm in length) in an average- sized adult, the depth of penetration is half the length of needle  Use of a “long” needle for posterior superior alveolar nerve block increases the risk of overinsertion and hematoma (can interrupt the pterygoid venous plexus)  Posterior superior alveolar nerve block using a “short” dental needle (∼20 mm in length)  Overinsertion is less likely. Better to use short needle If long needle only available  insert till half the needle only & avoid overinsertion Page 10 of 22 5. Infraorbital Nerve Block (Ant. & middle superior alveolar nerve block) Nerves Anesthetized  Anterior Superior Alveolar nerve  Middle Superior Alveolar nerve  Infraorbital nerve with its terminal branches:  Inferior palpebral  Lateral nasal  Superior labial  The solution is deposited at the orifice of the infra-orbital foramen  It will diffuse along the canal to involve both the anterior & middle superior alveolar nerves  Thus producing anesthesia of the incisors, canine & premolar teeth & their supporting structures Page 11 of 22  Technique  The infra-orbital ridge is palpated & the infra-orbital notch located with the tip of the index finger, which is then moved slightly downwards to lie directly over the infra-orbital foramen  With the fingertip maintained in that position, the thumb is used to reflect the upper lip & expose the site of injection  The tip of a long needle is directed towards the foramen, there are different three approaches indicated for the infra-orbital foramen: 1) The central incisor approach  Is by directing the syringe in a line passing oblique from the mesio-incisal angle of the central incisor, to its disto-cervical angle, & to apical region of the root of the canine  Which will usually be at the same level with the reflection of the muco-buccal fold  With the syringe held in this direction, the needle is inserted at about 5mm out in the muco-buccal fold above the tip of the root of the canine  The needle is then pushed inside the tissues for 2 cm until it contacts the bony boundary of the foramen 2) The second premolar approach:  Is by holding the syringe in the same line with the long axis of the upper second premolar, and inserting the needle at the reflection of the muco-buccal fold, above the tip of the root of that tooth In both approaches the correct position of the tip of the needle overlying the foramen is confirmed when the injection of the solution is felt beneath the palpating fingertip Page 12 of 22  3) Extraoral approach  It is an alternative technique used to block the infraorbital nerve in patient with infection in the path of intraoral needle insertion  The infraorbital depression can be located using the same method applied for intraoral approach then the needle inserted directly to the infraorbital depression perpendicular to the bone after swabbing the skin with a disinfectant solution  Avoid entrance of the needle into the infra orbital canal, it may penetrate its roof and the solution deposited into the orbital cavity, thus producing vision troubles 6. Maxillary Nerve Block  This injection is to anaesthetize the main trunk of the maxillary nerve & all its branches including the branches of the spheno-palatine ganglion  The whole maxilla will be anaesthetized by this injection  Maxillary teeth and their investing bone and soft tissues from both buccal and palatal aspects  There 2 approaches for the maxillary nerve block: 1) High Tuberosity Technique  Is the same as that described for posterior superior alveolar nerve block, with the exception that the needle is previously marked with depth of 1 ¼ inches  Needle inserted about 3cm to reach pterygopalatine fossa in proximity to the maxillary division of the trigeminal nerve The technique for high tuberosity & posterior superior alveolar:  Pull the tissues at the injection site taut (firm taut reflection)  Insert the needle into the height of the muco-buccal fold (depth of sulcus) over the upper 7  Advance the needle slowly in an upward, inward, and backward direction in one movement  Upward: superiorly at a 45-degree angle to the occlusal plane.  Inward: medially toward the midline at a 45-degree angle to the occlusal plane  Backward: posteriorly at a 45-degree angle to the long axis of the second molar Page 13 of 22 2) Greater palatine canal approach  From the palatal side, the greater palatine canal can be entered, and passed very slowly against no resistance, at a marked depth not exceeding 1 ½ inches reaching pterygopalatine fossa Page 14 of 22  Mandibular Anesthesia Techniques 1. Inferior Alveolar Nerve Block  The nerve is anesthetized before it enters the mandibular foramen  Nerves anesthetized are the branches peripheral to the site of injection (mental & incisive)  Areas anesthetized are:  Body of the mandible  Mandibular teeth, & lower lip at the side of injection  Buccal mucoperiosteum anterior to first molar  Patient position:  The patient is placed in the dental chair with his head tilted so that when the mouth is opened (widely opened to stretch the tissues) the mandibular occlusal plane is parallel to the floor  Operator position:  Stands in front & to the right side of the patient (for right-handed)  Stands in front & to the left side of the patient (for left-handed) When right-handed & giving anesthesia on the left side of the patient there are 2 options: 1) Cross-hand technique:  Stand in front & to the right of the patient  Landmark is taken with left hand  Right hand crosses above the left hand with the syringe to give the anesthesia 2) From behind the patient  Stand behind the patient  Landmark taken with left hand  Anesthesia is given with right hand from behind the patient  Can’t combine both techniques so either stand from in front with cross-hand technique or give anesthesia from behind the patient Page 15 of 22  Locating needle penetration site (Landmark) & technique  The index finger is placed in the muco-buccal fold opposite the premolar region  The finger is then advanced posteriorly until contact is made with external oblique ridge & then the anterior border of the ramus (finger staying in contact with the bone)  The finger is moved up & down on the anterior border of the ramus until the greatest concavity is felt, this is called the coronoid notch  The finger is then turned & redirected to be pointing medially/lingually  You will feel an elevation-depression-elevation (because this area is the intersection of the internal & external oblique ridges)  This is the retromolar triangle which has been crossed  The tip of the index finger should now rest on the internal oblique ridge while the rest of the distal phalanx rests on the retromolar & and the external oblique ridge  The finger is then moved slightly to the buccal side taking the buccal pad of fat with it (retraction)  This gives better exposure to the internal oblique ridge, pterygo-mandibular raphae and pterygo-temporal depression  The needle is inserted from the opposite premolar region (corner of mouth if edentulous) & parallel to the mandibular occlusal plane  The patient is asked to keep his mouth opened widely during the insertion of the needle (better exposure of pterygo-mandibular raphae)  injection given between finger & the raphae  The point of needle insertion is located 0.5 cm in front of the fingernail in the pterygomandibular depression at the level of the mandibular occlusal plane Page 16 of 22  The needle is inserted until 2/3 of the needle is inserted or at least half of the needle until bone is contacted (most importantly you must touch bone)  my target is the bony landmark before the nerve enters the mandibular foramen  When needle contacts bone, it’s in the region of pterygomandibular space, it’s withdrawn 1 mm, & about 1 mm of solution deposited slowly  The needle is then withdrawn halfway out (1-2mm) and 0.3ml of the solution is deposited, to anesthetize the lingual nerve  Whenever we give an inferior alveolar nerve block, we always anesthetize the lingual nerve with the same injection (as they are in the same area)  If we want to anesthetize the lingual nerve only, we do this step alone without the inferior alveolar injection, as the lingual nerve is more superficial  The remaining 0.2ml of the solution is injected buccally to anesthetize the buccal muco- periosteum at molar region (distal to the tooth being operated as the nerve moves from posterior to anterior)  Long buccal infiltration  For the lower anterior teeth innervation could be crossing the midline from the opposite side thus infiltration anesthesia in depth of the sulcus at 45 degree to long axis with bevel towards the bone mesial to the tooth to be extracted (direction of nerve is from mesial to the distal), for the interlacing fibers crossing the midline If early touch bone occurred during the direct technique:  Use indirect inferior alveolar nerve block  Withdraw the needle a little but still in the soft tissues  Place a few drops of anesthesia so the movement in the soft tissues is not painful  Redirection towards the midline then insert it about halfway inside  Then return to the needle position at the premolar area Page 17 of 22  Anatomical landmarks  Muco-buccal fold  External oblique ridge  Anterior border of the ramus  Coronoid notch  Retromolar triangle  Internal oblique ridge  Pterygomandibular raphe  Buccal sucking pad  Pterygomandibular space 2. Lingual Nerve Block  Is the same as for inferior alveolar nerve block  After needle contacts bone it is withdrawn 0.5cm & the solution deposited  Another method is by submucosal infiltration of 0.5ml of anesthetic solution a few millimeters below and behind the lower third molar. 3. Long Buccal Nerve Block  It is a branch of the anterior division of mandibular nerve  It passes downward between the two heads of lateral pterygoid muscle  It reaches the anterior border of masseter muscle at occlusal plane of third molar  The long buccal nerve crosses the external oblique ridge to innervate the buccal mucosa in the molar region  To nerve block it we must anesthetize before it gives branches  Proper site for long buccal nerve block  penetrate mucous membrane at the injection site, distal and buccal to the last molar  The needle is in contact with the external oblique ridge Page 18 of 22 4. Mental & Incisive Nerve Block  Blocking the mental nerve will result in anesthesia of the lower lip as well as the mucous membrane of the mucolabial fold anterior to the mental foramen  If anesthetic solution entered into the canal it will anesthetize anterior teeth, premolars, and investing bone  The mental foramen lies at the level of & just anterior to the apex of the second premolar  it’s opening is directed posteriorly Technique All retraction is with the mirror Only exception is when retracting for inferior alveolar  Stand behind the patient nerve block as the hand is used for taking the landmark  The cheek is retracted, this is facilitated by asking the patient to half close his mouth  The point of the needle insertion is prepared as usual (swabbing & painting)  Needle directed in a posterior direction & at 45-degree angle to the buccal cortical plate  About 1.5ml of anesthetic solution is deposited slowly when the needle contacts bone  The area around the foramen massaged gently to push solution into foramen (diffusion into the foramen)  Additional lingual nerve infiltration (few drops in the lingual sulcus) is needed as we didn’t give inferior alveolar so lingual mucosa isn’t anesthetized  When can I operate (how long for anesthesia to give effect) Infiltration  2 min Nerve block (inferior alveolar) we have two types of checking the effect  Subjective  by the patient’s own words (ask him about numbness)  He will feel numbness in 3 areas 1) Half of the lower lip Mental nerve which is a 2) Chin branch of inferior alveolar 3) Anterior 2/3 of the tongue  lingual nerve block  Objective  checked by the doctor  Probing between the 4 & 5 at the mental foramen  check inferior alveolar & mental nerve block) Page 19 of 22 5. Mandibular nerve block (The Gow – Gates Technique) Nerves Anesthetized (whole mandibular nerve) 1) Inferior alveolar nerve 2) Mental nerve 3) Incisive nerve 4) Lingual nerve 5) Mylohyoid nerve 6) Auriculotemporal nerve 7) Buccal nerve (in 75% of patients) Technique  With the patient lying fully reclined in the chair, have the patient open his/her mouth as wide as possible  This technique is not possible(contraindicated) if the patient is not able to open wide enough to allow the condyles to translate fully over the articular eminences  Place your thumb in the patient's mouth retracting the cheek  the thumb should be relatively close to the site of the entry point of the needle.  Palpate the coronoid notch & slide the finger or thumb to rest on the internal oblique ridge  Move the finger or thumb superiorly around 10 mm  Rotate the finger or thumb to parallel an imaginary line from the ipsilateral corner of the mouth to the tragal notch of the ear  Place the middle finger of the same hand over the intertragal notch  this landmark is easily felt with finger  Thus the hand is held in a "C" with the thumb inside the mouth retracting the cheek and the middle finger outside the mouth placed firmly over the intertragal notch.  Now aim the tip of the needle toward the intertragal notch  Using a long 27 gauge needle, & holding the handle of the syringe at about the level of the lower premolars, allow the needle to enter the buccal mucosa just distal to the maxillary second molar at the height of its mesio-palatal cusp Page 20 of 22   Proceed until the needle hits bone  If the needle does not hit bone  then you have missed the target and should withdraw and try again, aiming slightly laterally, or medially (we use bony landmark so we must touch bone)  Once bone is contacted, withdraw the needle tip 1 mm to prevent injecting into the periosteum, which would be painful  Aspirate  Inject a full cartridge  Note  This is not a deeper injection, because the patient's mouth is open wide so the condyle has translocated anteriorly to provide a target 6. Vazirani-Akinosi Closed-Mouth Mandibular Block  It is a useful technique for patients with limited opening due trismus or ankylosis of the temporomandibular joint (for patient’s who can’t open wide open as in Gow-Gates)  A 25 gauge long needle is recommended for this technique Nerves Anesthetized 1) Inferior alveolar nerve 2) Incisive nerve 3) Mental nerve 4) Lingual nerve 5) Mylohyoid nerve 6) Long buccal could be anesthetized in some cases Technique  The gingival margin above the maxillary 2nd & 3rd molars & the pterygo-mandibular raphae serve as landmarks for this technique  The patient should close gently on the posterior teeth  The needle is held parallel to the occlusal plane at the level of the gingival margin of the maxillary 2nd and 3rd molars  The bevel is directed away from the bone facing the midline  No touch bone in this technique!  The needle is advanced through the mucous membrane & buccinator muscle to enter the pterygomandibular space Page 21 of 22  The needle is inserted to approximately one half to three quarters of its length  At this point the needle will be in the midsection of the ptyerygo-mandibular space Page 22 of 22  Practical Surgery 5 Dental Forceps Parts of the forceps Blade / working part / beaks  It’s what determines the use of the forceps Joint / hinge Handle Upper vs Lower  If blade is right angle with the handle  Lower  If blade is with the long axis of the handle or angulated  Upper Upper Lower  Upper forceps Upper anterior forceps {Straight forceps}  Called straight as the handle, joint & blade are on the same line  Used for extraction of upper anterior teeth {1/2/3}  Can have different sizes (bigger for canine)  When the forceps is closed the beaks don’t touch (slighty opened to accommodate the size of the tooth) where:  We don’t have to open the handles widely to grab the tooth  When the tooth is grabbed the handles aren’t too far away from each other so we can easily close them and grip the tooth When opening the beaks to grab the tooth, the beaks are already slightly opened so you open the handle slightly as well  this prevents making a huge distance between the two handles when closing the beaks again around the tooth Page 1 of 4  Upper premolar forceps  Used for extraction of upper premolars right & left {4/5}  Angulation in the blade for accessibility  The design of the handle is not related to the blade angulation  The handle is usually curved so we hold the forceps where the concave side is on the palm of the hand Upper molar forceps  Used for extraction of upper right & left molars  There are 2 types of upper molar forceps  upper right & upper left  Has a projection on the buccal beak on the buccal side for the buccal bifurcation  The palatal beak is concave to accommodate the convex palatal root of upper molars  Differentiated that when holding them in the right way (concavity of handle on the palm), the projection should be on the buccal side of the tooth (projection of beak towards the cheek)  Upper left molar forceps  projection on the left of the patient (on my right)  Upper right molar forceps  projection on the right of the patient (on my left) The concavity of the handle towards the table (simulates the correct grip) & the arrow points to the projection) Upper right molar forceps Upper left molar forceps  Projection on right of patient / my left  Projection on left of patient / my right Page 2 of 4  Upper remaining root forceps {Reed’s Forceps}  Used for extraction of upper remaining roots  Slightly angulated blade to the handle  Narrow closed beaks Upper third molar forceps  Used for extraction of upper third molar {8} when it’s a full crown  The used name for upper third molar forceps is  Open Bayonet  While the name for upper third remaining root forceps  Closed Bayonet  But the correct Bayonet name alone is for the upper third molar remaining root Upper third molar remaining root forceps {Bayonet}  Used for extraction of upper third molar {8} when its fractured or a remaining root  Angle is for accessibility Page 3 of 4  Lower forceps Lower anterior forceps / lower remaining root forceps  Used for extraction of lower anterior teeth {1/2/3} & lower remaining roots  Identified as lower forceps as blade is right angled to the handle  The beaks are closed unlike the upper Lower premolars forceps  Used for extraction of lower premolars {4/5}  Same design as lower anterior forceps but has opened beaks  Doesn’t have projections Lower full crown (molar) forceps  Used for extraction of lower molars  Has a projection on both beaks for the buccal and lingual bifurcations  We don’t have right or left since it’s used for both right & left as the projection is on both beaks Cowhorn forceps / American design  Used for extraction of lower molars  Angle of blade is also right angled but made so that we grab the tooth buccolingual from the front (incisors area) & not from buccal (cheeks) as usual Page 4 of 4  Practical Surgery 6 Elevators Definition:  Dental elevator is a dental instrument used for removing of teeth or the roots of teeth which cannot be gripped with forceps (not enough crown structure to grip where slippage occurs) Parts:  Blade, shank, and handle Indications: 1) Luxation of teeth 2) Remove remaining roots (where remaining root forceps can’t grip it) 3) Remove broken roots 4) Remove inter-radicular bone (for example a case of separation for a lower 6 or 7 where the mesial root removed but the distal root is still there  enter the empty mesial socket with the elevator and remove the inter-radicular bone & the distal root) Rules for the use of elevators 1) Never use the adjacent tooth as a fulcrum (except if it’s indicated for extraction as well) 2) Never use buccal plate of bone as a fulcrum except during extraction of lower 2nd and 3rd molars (as there’s thick buccal bone of the external oblique ridge) 3) Use finger guard to avoid injury to the adjacent soft tissue 4) Support the shank with your index to avoid slipping of the elevator 5) Note  Using elevators is contraindicated in maxilla (as its spongy/cancellous bone & avoid communication with maxillary sinus) except Warwick James elevator which is very light and apply a delicate force 6) Straight apexo elevator maybe used for luxation of maxillary third molar in a distobuccal direction Correct grip and supporting shank with index finger Page 1 of 5  Principles: (mechanism of how the elevator works) 1) Wedge  Mainly with straight elevators  At 45 degree or parallel with the long axis of the tooth  The socket normally just fits the tooth  by forcing (wedging) the elevator mesial or distal to the root, the root starts to be dislodged coronally where it can be gripped with the forceps 2) Lever  With curved elevators  Must have a fulcrum to rest on  Force applied on point of effort that has a resulting force on point of load  if the effort is larger than the resistance then the root starts to be removed 3) Wheel and Axle  Cross bar elevator only  Effort applied to the circumference of the wheel transferring the force to the axle that elevates the load  In cross bar, the handle is much larger than the blade tip  applying small effort at the handle multiplies this force at the blade as it’s a small area causing it to elevate the root Page 2 of 5   Forms of elevators  Straight  Curved  Cross bars Straight elevators mainly Straight apexo elevator use a wedge principle  Principle  wedge  Blade has 2 sides a convex side (toward the bone) and a concave side (toward the root to be extracted)  It is characterized by tapered end / pointed tip Coupland chisel  Principle  wedge  Characterized by flat end  A bit wider and applies more force than the straight apexo Straight Hospital pattern  Principle  wedge  Very large force that it can be used alone for extraction of lower third molar {8}  Characterized by serrated blade Sometimes handles can have serrations or not which I don’t care about  the importance is if there’s serrations in the blade then it’s a hospital elevator (lowest force) Straight apexo  Coupland chisel  Straight hospital pattern (highest force) Straight Warwick James  Principle  wedge  Used in luxation of maxillary teeth (only one that can be used in maxilla as it applies delicate force)  Characterized by its light weight Page 3 of 5  Curved apexo elevator  Principle  lever  Has a curvature between the shank & blade  Used in extraction of lower remaining roots / separated molars  It comes in right & left forms  Characterized by tapered / pointed tip Apexo elevators are characterized by tapered end / pointed tip whether straight or curved Buccal applicator / Cryer’s elevator  Principle  lever (buccal applicator name as it uses buccal plate of bone as fulcrum)  Used in removal of lower molars remaining roots {mainly 8} with sound furcation  It is presented in right & left forms  Characterized by a triangular blade / triangular working part  The handle and blade are on the same plane (differs from cross bar) Curved hospital pattern  Principle  lever  Characterized by serrated blade (hospital)  Presented in right & left forms  Not used a lot as it’s heavy & can fracture the mandible  Can be used in removing inter-radicular bone with a remaining root after separation Page 4 of 5  Curved Warwick James  Principle  lever (differ from the straight Warwick James)  Used in maxillary teeth Cross bar / Winter’s elevator  Principle  wheel and axle  It has a triangular blade / triangular working part (like Cryer’s)  The handle and blade are not on the same plane (differs from Cryer’s)  the plane of the handle & blade is what makes the principles used different as well  The handle is large compared to the small area of the blade so when we rotate the handle with a small force it  the force transmitted is multiplied & can elevate the roots Page 5 of 5  Practical Surgery 7 Extraction of Teeth Requirements of Ideal Extraction 1) Satisfactory access and visualization of the field of surgery (bloodless field) 2) An un-obstructed pathway for the removal of the tooth 3) The use of controlled force to luxate & remove the tooth (no sudden movements) 4) Beaks should seated as far apically as possible (apical grip beyond cementoenamel junction to decreases risk of fracture of the tooth) 5) Beaks should be parallel to the long axis of tooth 6) Avoid excessive force  Patient Position For a maxillary extraction  The chair should be tipped backward (semi-supine) & maxillary occlusal plane is at 60 degrees to the floor  The height of the chair should be that the patient's mouth is at or below the operator's elbow level For the extraction of mandibular teeth  The patient should be positioned in a more upright position  The occlusal plane is parallel to the floor  The chair should be lower than for extraction of maxillary teeth  Surgeon Position For all maxillary teeth and anterior mandibular teeth  The dentist is to the front and right {7 O’clock}, or to the left, for left-handed dentists {5 O’clock} of the patient For the posterior mandibular teeth  The dentist is positioned behind and to the right {11 O’clock}, or to the left, for left-handed dentists {1 O’clock} of the patient In all the teeth the surgeon is position in front and to the right except lower posterior teeth we stand behind the patient Page 1 of 2  Technique of forceps extraction:  The forceps should be grasped by the palm of right hand & the thumb is placed below the joint for better control  In extraction of upper teeth the fingers of left hand are used for reflecting lips, cheek and supporting the alveolar process on both labial, buccal, and palatal side  While in extraction of lower teeth the fingers of left hand are used for reflection of the lip, check, tongue and supporting the alveolar process and supporting the mandible to prevent the dislocation of mandible and post-operative pain Displacement of the tooth from its socket:  Displacement depend on root morphology (as forceps choice depends on root since we grip beyond the cementoenamel junction & not the crown), this is performed by using the extraction movements:  Lateral or bucco-lingual movements for all teeth except Upper central incisor and lower premolars  Rotation movement for Upper central incisors and lower 2nd premolar (conical roots)  Sometimes need to modify the technique by feeling the direction a tooth wants to go (feel what the tooth wants to do)  Maxillary buccal bone is thinner  buccally removal of teeth  Mandibular buccal bone till molar is thinner  buccally removal of teeth  Mandibular buccal bone in molar region is thicker (lower 7 & 8 because of the external oblique ridge)  lingually removal of teeth Initial movement  apical grip for all teeth Primary movement  bucco-lingual or lateral movement for all teeth except upper central incisors & lower 2nd premolar we use rotational movement Post-operative instructions (3 Do’s & 3 Don’ts) 1) Bite on a piece of gauze for 30 minutes 2) Eat soft food on day of extraction 3) Eat on the other side 4) Do not gargle on day of extraction (also no mouth rinsing or mouth washes) 5) Do not eat or drink hot beverages or food 6) Do not smoke Page 2 of 2  Practical Surgery 8 Surgical Instruments Includes Instruments used for teeth extraction (Extraction forceps - Dental elevators) Instruments used for local anaesthetics Instrument Used for Holding the Drapes Instruments Used for Incising the Tissues Instruments Used for Retracting Tissues Instruments Used for Reflecting the Mucoperiosteal Flap Instruments Used for Holding the Soft Tissues Instruments Used to Keep the Mouth Open Instruments Used to Remove Pathologic Tissue Instruments Used to Cut or Remove Bone Instruments Used to Hold the Bone Instruments Used to Suture the Tissues Objectives → Identify & name the instrument & its uses ❖ Instrument Used for Holding the Drapes Towel clips / Towel holder Uses: 1) To hold the corners of the draping sheets during an operation 2) To hold the tongue Page 1 of 9 ❖ Instruments Used for Incising the Tissues Scalpel The instrument used for making an incision is called a scalpel The scalpel has two parts, a blade & a blade handle. Bard Parker Blade / Scalpel Handle Various sizes of the handles are available. The most commonly used handle in oral surgery is No. 3 The handle has a receiving slot for the blade Blades No. 10 → For making skin incision (extraoral) (large) → example, submandibular incision No. 11 → For making stab incisions → example, to drain an abscess No. 12 → For inaccessible areas (has a curvature) → example, tuberosity & retromolar area No. 15 → For intraoral surgery (smaller compared to No.10) 10 11 12 15 Page 2 of 9 ❖ Instruments Used for Retracting Tissues Retractor / Cheek retractor Uses: 1) Retract the soft tissues (cheeks) 2) Retract incision edges → example, retracting an extended buccal flap Tongue Depressor Uses: 1) To depress the tongue for visualization of the tonsils & the pharyngeal wall during inspection 2) To depress the tongue during endotracheal intubation & extubation in general anesthesia 3) To retract the tongue during surgical procedures in the oral cavity 4) To retract the cheek Page 3 of 9 ❖ Instruments Used for Reflecting the Mucoperiosteal Flap Periosteal Elevators Uses: 1) The pointed end is used to release the interdental papillae 2) The broad end is used for elevating the mucoperiosteal flap from the bone, & can also be used as a soft tissue retractor Method of Reflecting the Periosteum from the Flap: ➔ Push stroke → It is given with the concave side of the broad end of the periosteal elevator (concave part towards bone while convex facing the soft tissue) & is the most efficient stroke to reflect the periosteum from the bone ❖ Instruments Used for Holding the Soft Tissues Haemostatic Forceps (artery forceps) Types of Haemostats: ➔ Large / Medium / Small (according to size) ➔ Straight / Curved A small curved artery forceps is known as a mosquito forceps Uses: 1) To achieve haemostasis by catching blood vessel 2) For evacuation of pus to drain an abscess Has serrations in one direction that differentiates it from a needle holder Working tip is long and thing Page 4 of 9  Allis‘ Tissue Holding Forceps Uses: 1) Grasping soft tissues to be removed 2) Grasping soft tissues for histopathological examination (biopsy) Has serrations on the working tip (differentiates it from artery forceps & needle holder) Tissue Holding Forceps 2 Types: ➔ Plain (non-toothed) → can have serrations still along the tip ➔ Toothed Uses: 1) The plain forceps having no tooth at the tip & are used for holding delicate structures like the peritoneum, fascia, delicate muscles & facial skin, non-keratinized tissues → They are also used to hold blood vessels or nerves 2) The toothed forceps are used to hold tough structures like the aponeurosis & coarse muscles, keratinized tissues → They are also used to hold the needles while suturing Plain Plain Toothed Toothed Page 5 of 9 ❖ Instruments Used to Keep the Mouth Open Mouth Prop Mouth Gag ❖ Instruments Used to Remove Pathologic Tissue Curette / Bone curette Uses 1) It is used to remove tooth particles or debris from the extraction socket 2) To remove pathological tissues → enucleate cysts, periapical granulomas, intraosseous tumors 3) To remove proliferative or infected clot from the extraction socket Page 6 of 9 ❖ Instruments Used to Cut or Remove Bone Bone File Smoothen any sharp bony margin present in the surgical field The working ends have horizontal serrations The instrument is used unidirectionally using a pull stroke A push stoke usually causes burnishing and crushing of the bone Rongeurs Forceps 2 Types ➔ Side cutting only ➔ Both side & end cutting (universal) Uses 1) To nibble sharp bony margins after simple or surgical extraction of teeth, surgical procedures 2) To peel off thinned out bone present over cystic or tumorous lesions. 3) To trim sharp bony ridges during alveoloplasty procedures Side & end cutting Side cutting Page 7 of 9  Chisel Chisels are unibeveled instruments for cutting bone The edge of the working tip has a bevel on one side Working edge is sharp & flat → to cut the bone, the bevel is kept facing away from the bone Uses: ➔ To remove chips of bone as in transalveolar extractions Osteotome The osteotome is similar to a chisel, but the edge of the working tip is bibeveled Uses ➔ To split/section the tooth in difficult extractions Mallet (hammer) A mallet is made up of steel, lead, or wood It is similar to a hammer & is used for giving controlled taps on the chisel or osteotome Page 8 of 9  Hand Piece and surgical burs Burs are rotary instruments that cut the bone They are made up of either stainless steel or carbide They are available in different lengths, shapes (Fissure, round, tapering fissure) and sizes Uses 1) To round of sharp margins after extractions, minor surgical procedures 2) To aid in bone removal or splitting the tooth, during impaction (guttering & decapitation) 3) To round of sharp ridges during alveoloplasty procedures 4) To perform osteotomy cuts 5) To release bony ankylosis 6) To make a bony window for access to cystic cavities & tumors 7) To perform resection of the maxilla, mandible ❖ Instruments Used to Hold the Bone and Soft Tissues Kocher’s tissue forceps Can hold hard or soft tissue (fibrous consistency) This instrument is similar to artery forceps, but it has a toothed tip Uses 1) The instrument is specially designed to hold the coronoid process during coronoidectomy procedure 2) For stabilization of the bony fragment (during reduction & fixation in fracture) 3) To hold the salivary glands, especially the submandibular and the sublingual glands 4) To hold enlarged lymph nodes. 5) To hold tumors during excision. Page 9 of 9  Practical Surgery 9 Principles of Dental Suturing Why do we suture? 1) Sutures are used in surgery for re-approximation of tissues serrated by surgical or accidental trauma without tension 2) To promote healing 3) Control of hemorrhage After all the necessary procedures are completed: 1) The area is re-examined and cleansed 2) The flap is placed back with no tension 3) It is preferred to keep the flap in position with light finger pressure for 1min ❖ Armamentarium 1. Needle Holder: The needle holder is an instrument with a locking handle & a short, blunt beak Why can’t a haemostat be used instead of the needle holder? ➔ The beaks of a needle holder are shorter & stronger than the beaks of a hemostat (shorter beaks also give better control) ➔ The face of a beak of the needle holder is crosshatched (criss-cross serrations) with a single vertical serration to permit a positive grasp/grip of the suture needle. The hemostat on the other hand has parallel grooves on the face of the beaks, thereby decreasing the control over needle and suture → Therefore the hemostat is a poor instrument for suturing Page 1 of 13  To control the locking handles properly & to direct the long needle holder the surgeon must hold the instrument in the proper fashion: ➔ The thumb & ring finger are inserted through the rings (not thumb & index like normal scissors) ➔ The index finger is held along the length of the needle holder to steady & direct it (for best guidance the finger has to be as close as possible to the joint) ➔ The second/middle finger aids in controlling the locking mechanism ➔ The index finger should not be put through the finger ring because this will result in dramatic decrease in control. 2. The Suture needle Needle is curved allowing it to pass through a limited space (for accessibility), where a straight needle can’t reach Suture needles come in a large variety of shapes & curvatures, from very small to very large ➔ The higher curvature 1/2 circle suture needle used for more inaccessible areas 3/8 1/2 Page 2 of 13  Needle point 1) Tapered Round/Circular cross-section These tips are used for more delicate tissues such as for ocular or vascular surgery Characteristically they are rounded & produce the smallest hole, minimizing trauma Not used in oral cavity as we suture tougher tissues (muscles & mucoperiosteum) 2) Cutting They are triangular shaped cross-section & are useful in puncturing tough tissue like mucoperiosteum, they produce a larger hole than tapered tips, there are 2 types: ➔ Regular cutting tips → the cutting edge is on the inner curvature (triangle facing upward) ➔ Reverse cutting tips → the cutting edge is on the outer curvature (triangle facing downward) In oral cavity we always use Reverse cutting tips → as it cuts from the outer surface/curvature, this minimizes the trauma while suturing & decrease lacerations to the tissues The cutting portion of the needle extends about one third the length of the needle, & the remaining portion of the needle is round → to minimize the trauma The suture material is now usually purchased already swaged (linked to the needle) on by the manufacturer The curved needle is held approximately two thirds of the distance between the tip & the base of the needle → This allows enough of the needle to be exposed to pass through the tissue, while allowing the needle holder to grasp the needle in its strong portion → to prevent bending of the needle (gives maximal control over the needle) Page 3 of 13 3. Suture Material Many types of suture materials are available, the materials are classified by : ➔ Diameter ➔ Resorbability (resorbable or non-resorbable) ➔ Whether they are monofilament or polyfilament Diameter: The size of suture relates to its diameter & is designated by a series of zeros ➔ The more zeroes → the thinner the suture material is The diameter most commonly used in the suturing of oral mucosa is 3-0 (000) ➔ Sutures of size 3-0 are large enough to withstand the tension placed on them intra-orally and strong enough for easier knot tying with a needle holder A larger size suture is 2-0 (00), or 0 → used in skin A smaller size suture is 4-0, 5-0, and 6-0 → used in more delicate structures (eye or vessels) Sutures of very fine size, such as 6-0 (000000), are usually used in conspicuous places on the skin, such as the face for less scarring Non resorbable: Silk → braided / polyfilament Nylon → monofilament Resorbable (either natural or synthetic): 1) Natural Resorbable sutures are primarily made of gut (stomach of sheep) Although the term catgut is often for this type of suture, gut actually is derived from sheep intestines ➔ Plain gut → monofilament → (resorbed in 3-5 days) ➔ Chromic gut (Plain gut treated by chromic acid to extend period which it stays inside the mouth) → monofilament (stays up to 7-10 days before resorbing) 2) Synthetic Several synthetic resorbable sutures are available like polyglycolic acid & polylactic acid sutures These materials are slowly resorbed, taking up to 4 weeks before they are resorbed Such long-lasting resorbable sutures are rarely indicated in the oral cavity for basic oral surgery The most commonly used type in major oral surgeries is Vicryl that is 90% polyglycolic acid and 10% polylactic acid Page 4 of 13  Monofilament Vs Polyfilament (Braided) Monofilament → only 1 thread → Nylon Polyfilament / braided → more than 1 filament braided together → Silk ➔ Sutures that are made of braided material (Why is Silk preferred) are stronger & have better knot stability (memory of material to return to its original shape is decreased after braiding) ➔ The cut ends are usually soft and non-irritating to the tongue & surrounding soft tissues, this is why Nylon {monofilament} is never used intraorally as it’s so irritating ➔ BUT → They allow bacteria from the oral cavity to be drawn through the suture to the deeper area of the wound (due to the braids) → so never leave a silk suture more than 7 days One of the most commonly used sutures for the oral cavity is 3-0 black silk The size 3-0 has the appropriate amount of strength, the polyfilament nature of the silk makes it easy to tie and well tolerated by the patient's soft tissues. The color makes the suture easy to see when the patient returns for suture removal Sutures that are holding mucosa together usually stay no longer than 5 to 7 days, so the wicking action is of little clinical importance Details that we know from the suture packet (example from the packet above) Type of suture material → Silk braided {all silk are braided} Length → 75cm Thickness (diameter) → 3-0 Needle → 3/8 circle, reverse cutting (with inverted triangle drawn) Page 5 of 13 4. Tissue Holding Forceps: Toothed, to hold the flap in place while suturing (for a positive grasp on the flap) There is non-toothed for the more delicate structure but in oral cavity we deal with tough so we use the toothed 5. Suture Cutting Scissors: The final instrument necessary for placing sutures The suture scissors usually have short cutting edges because their sole purpose is to cut sutures (the knot is cut leaving short edges to identify the suture while removing it) ❖ Principles of suturing 1) The needle should be grasped by the needle holder at approximately one-third (1/3) the distance from the eye & two-thirds (2/3) from the point/tip 2) When passing the needle through the tissue The needle should enter the surface of the mucosa at a right angle, Why? ➔ To make the smallest possible hole in the mucosal flap ➔ If the needle passes obliquely, the suture will tear through the surface layers of the flap when the suture knot is tied, which results in greater injury to the soft tissue When passing the needle through the flap the surgeon must ensure that an adequate amount of tissue is taken, Why? ➔ The amount of tissue between the suture & the edge of the flap (bite distance) must be a minimal of 3 mm (distance between edge of flap & point of penetration) ➔ To prevent the needle or suture from pulling through the soft tissue flap 3) The needle should be passed through the tissues along its curve 4) The suture should be passed at an equal depth & distance from the incision on both sides 5) The needle always passes from the movable tissue to the fixed tissue 6) The needle always passes through the thinner tissue to the thicker tissue Start from the tissue that I have less control on (mobile & thin) Page 6 of 13 7) Tissues must never be closed under tension (just approximation of the tissues) 8) The suture should be tied only to approximate the tissues, not to blanch, Why? Sutures that are too tight/under tension cause ischemia of the flap margin and result in tissue necrosis, with eventual tearing of the suture through the tissue Thus sutures that are too tightly tied result in wound dehiscence more frequently than sutures that are loosely tied 9) The knot is preferred to be buccal (better visibility of the knot than the lingual side when removing), & knot should never lie on the incision line, Why? Because this knot lays additional pressure/stresses on the incision line that I want to heal Can be a source for accumulating bacteria & debris on the incision line 10) Sutures on the skin are usually removed in 5 days & intraoral sutures in 7 days, if there is tension while suturing, the sutures may be kept for 10 days (never more than 10 days as long standing sutures can transfer bacteria deeper into the wound) 11) Sutures should be spaced about 5 to 7 mm apart is more than enough Page 7 of 13  ❖ Surgical Knot Tying For example if point of penetration of needle was buccal (it was mobile), & through the lingual side (long end will be lingual) 1) Wrap the long end (lingual) around the shaft of the shaft of the needle holder twice (care for the joints of needle holder) 2) Grab the short end with the needle holder (buccal) and pull in opposite directions perpendicular to the incision line to tie the first knot (make sure knot is on the buccal side) 3) Repeat again by wrapping once but if first time we wrapped the suture clockwise around the needle holder, we change the second time to anti-clockwise & so on → to prevent the memory of the suture material from acting, providing a higher knot stability A → point of entry and exit of the suture resulting in a long end that has the needle and the short end B → Wrap the long end twice around the needle holder (once clockwise & the next knot anti-clockwise, then clockwise again and so on) C → Grab the short end with the needle holder D → Pull in opposite directions & perpendicular to the incision line To provide highest knot stability (key for approximation of the suture & prevent its failure) Wrapping once clockwise & the other anti-clockwise for the material memory Pulling the knot perpendicular to the incision line Knot never lie on the incision line to prevent additional stresses Page 8 of 13  ❖ Types of Sutures 1) Simple interrupted suture: Just one suture penetrating the tissues on one side then exit on the opposite flap & tie a knot Most commonly used Advantages: ➔ It is strong & can be used in areas of stress ➔ Successive sutures can be placed according to individual requirement (easy to use) ➔ Each suture is independent & the loosening of one suture won’t loosen any other ➔ A degree of eversion can be controlled. ➔ If the wound becomes infected or there is a hematoma formation, removal of a few sutures may offer a satisfactory treatment (each suture is independent & doesn’t affect whole flap) 2) Figure of eight suture: The figure of eight suture, occasionally placed over top of socket to aid in hemostasis Moreover, this suture is usually performed to help maintain/stabilize piece of oxidized cellulose in tooth socket Technique ➔ For example, start entry buccal then exit the flap & cross lingual diagonally to the opposite side, then enter the tissues from the lingual then exit tissues from the buccal of same side ➔ Then criss-cross to lingual diagonally again and enter the tissues from the lingual ➔ Exit tissues buccal same side to finish the figure of 8 ➔ This results in the suture making a cross above the socket stabilizing the material placed inside the socket Disadvantages ➔ Presence of suture material above the socket causes stress & can accumulate bacteria & debris above the socket = Point of entry Page 9 of 13 3) Continuous simple suture: Technique ➔ For example, starts with normal interrupted suture & a knot ➔ Instead of cutting both ends, we cut the short one while using the long end to continue suturing 5mm along the incision ➔ Then penetrate & exit the tissues along the incision ➔ In the last suture we tie the last knot & cut Advantages ➔ It provides a rapid technique for closure (specially for long incisions → alveoloplasty of the arch) and distributes the tension uniformly over the suture line ➔ It also offers a more watertight closure Disadvantages ➔ Can cause extra tension on the edges of flap & can cause eversion as the suture continues ➔ If one suture loosens, the whole series of sutures is loosened & should be removed and made all over again → We overcome this problem with continuous interlocking 4) Continuous interlocking suture: Technique ➔ Is similar to the continuous suture, but locking is provided by withdrawing the suture through its own loop before moving to the next suture → entry then exit on opposite flap then pass through its own loop before moving for the next suture The suture thus passes perpendicular to the incision line Advantages ➔ The locking prevents excessive tightening of the suture as the wound closure progresses → less tension ➔ If one suture loosens, the locking mechanism provides considerable wound closure till the time the whole suture can be replaced Page 10 of 13 5) Distal Wedge Suture: Distal wedge suture is a special type of sling suture used after the removal of impacted lower third molar It aims at holding the distal tissue wedge tightly to the second molar tooth to prevent distal pocket formation, which is the most common postoperative complication after impactions ➔ Distal tissue wedge → triangular tissue wedge that was the interdental papilla buccal & lingual between the 7 & 8 → when sutured together they are heavy & not attached to any underlying structures so they just fall causing a distal pocket accumulating food debris & bacteria) Technique: ➔ Start buccal for example & penetrate the tissues ➔ Then before exiting from the lingual, we loop around the second molar {7} (slinging), passing the mesial contact from lingual to buccal side where the suture is stabilized around the tooth ➔ Exiting lingual after the loop going out of the tissues as an interrupted suture & tying a knot ➔ That results that the distal tissue wedge is hanging on the 7 preventing the distal pocket Page 11 of 13  Mattress Sutures: These sutures may be horizontal or vertical These are used in areas, where tension free flap closure cannot be accomplished They are watertight sutures Mattress sutures are also used to resist muscle pull, evert the wound edges & to adapt the tissue flaps tightly to the underlying structures (making it watertight) ➔ Used in → oro-antral communication, bone grafts, tissue grafts, dental implant, regenerative membrane 6) Horizontal Mattress suture: The suture is horizontal & looks parallel to the incision line Use of this suture decreases number of individual sutures that have to be placed. However, more importantly, it compresses wound together slightly & everts wound edges causing a watertight suture & stabilizes the flap over underlying structures Technique ➔ Start as interrupted where we gain entrance for example on buccal then exit from lingual ➔ Move horizontally in the lingual side around 5mm (distance between sutures) & penetrate the tissues again then exit buccally ➔ Tie a knot with the 2 buccal ends of the suture resulting in the visible suture going horizontal & parallel with the incision line How it’s visible from the outside Dotted → inside the tissues Page 12 of 13 7) Vertical Mattress suture: It is similar to the horizontal mattress, except that, all factors remaining constant, the depth of penetration varies (suture is on 2 depths) → when the needle is brought back from the second flap to the first, the depth of penetration is more superficial It is used for closing deep wounds → so we don’t close the superficial wound only, leaving the deep dead space causing hematoma that can get infected ➔ Mostly used in deep wounds of the skin ➔ In the oral cavity we use the horizontal mattress Technique ➔ For example start entrance from buccal where the first penetration is deep into the tissues then exit from the lingual ➔ From the lingual side again penetrate the tissues at the same plane (not moving to the sides as in horizontal mattress) but it will be at a closer distance to the incision line & the depth is more superficial to the first penetration ➔ Tie the knot at the buccal where u have the 2 ends and it looks like the suture is vertical & perpendicular to the incision line Far-far then near-near → first penetration entrance is far from incision line & exit is also far (deep suture), then re-entry is near & it exits near (superficial suture) Vertical mattress Horizontal mattress ❖ Suture Removal (for non-resorbable sutures) Identify the knot (we leave a small part of the 2 ends of the knot while cutting after the suture for identification) Grab it with a tweezer & cut the suture from beside the knot Pull the knot after cutting & the whole suture will come out Done after 7 days or a maximum of 10 days Page 13 of 13  Practical Surgery 10 Radiographs in Surgery Why we need imaging:  To confirm the diagnosis  To aid in formulation of proper surgical treatment plan  To guide the surgeon during operation (image guided surgeries)  To see the results of the treatment & for follow up  To record the cases for medico-legal purposes Imaging techniques used in dentistry can be categorized as:  Intraoral & extraoral  Analogue (with film) & digital (image on computer/software)  Ionizing (x-ray) & non-ionizing imaging (MRI)  Two-dimensional {2-D} & three dimensional {3-D} imaging 1. Intraoral a) Periapical b) Occlusal c) Bitewing a) Periapical  Single impaction  Remaining root & difficult extraction  Assess tooth at fracture line Page 1 of 29  b) Bitewing radiograph  Early recognition of proximal caries (For conservative dentistry)  To assess alveolar bone height c) Occlusal radiograph  Shows buccolingual dimension  Localization of impacted canine  Detection of salivary gland stones (specially floor of mouth Maxillary Occlusal  If lesion caused buccolingual expansion  Maxillary occlusal views:  Vertex occlusal  Upper standard occlusal  Upper oblique occlusal Mandibular Occlusal  Mandibular occlusal views  Lower 90◦ occlusal  Lower 45◦ occlusal  Lower oblique occlusal Vertex occlusal Upper standard occlusal Upper oblique occlusal Lower 90◦ occlusal Lower 45◦ occlusal Lower oblique occlusal Page 2 of 29  Indications of occlusal radiographs  To locate roots & supernumerary, unerupted & impacted teeth  To localize foreign bodies in the jaw & stones in the ducts of salivary glands  To obtain information about the location, nature, extent & displacement of fractures of the mandible & maxilla  To determine the medial & lateral extent of pathologies (cysts, osteomyelitis, malignancies) & detect disease in the palate or floor of the mouth Fracture of mandible & displacement of the two segments 2. Extraoral radiographs  For middle & lower thirds of the face a) Panoramic {OPG}  overall image of maxilla & mandible (for multiple extractions & fractures in the mandible more than maxilla) b) Lateral cephalometric c) Lateral oblique (modification of true lateral cephalometric)  angle / body / ramus of mandible (used for impacted wisdom) d) Postero-anterior {PA}  body, angle & ramus of mandible (doesn’t show condyles) e) Reverse Towne view (modification of postero-anterior) condylar & sub-condylar area  For middle third of the face f) Standard Occipito mental  shows mid face g) 30◦ occipito mental h) Waters view (modification of occipito-mental) for maxillary sinus i) Submento-vertex view  zygomatic arch Page 3 of 29  a) Orthopantomography {OPG} (Panoramic)  Pantomography is derived from two words  Panorama & tomography  Ortho  straight  Panoramic  an unobstructed or a complete view of the object in every direction  Tomography  An x-ray technique for making radiographs of layers of tissue in depth, without the interference of tissue above & below that level  The machine rotates around the head & takes different cuts to the maxilla & mandible  The cuts are joined together to give a final straight overall image of maxilla & mandible Uses of panorama  Multiple impaction  Fracture (in mandibular fracture more than maxilla)  Assess lesion  cyst or tumors  Overall view Normal anatomic structures that appear in the panorama  Check if bilateral & if its normal anatomic landmark to not be confused as a lesion  Mandibular condyle  Hard palate  Zygomatic bone  Inferior orbital canal & foramen  Coronoid process  Floor of maxillary sinus  Inferior border of mandible  Lateral pterygoid palate  External auditory meatus  Zygomatic process of maxilla  Articular eminence  Mandibular fossa  Pterygomaxillary fissure  Mental foramen  Inferior orbital rim  Hyoid bone  Anterior wall of maxillary sinus  Inferior alveolar canal  Nasal fossa  External oblique ridge Page 4 of 29 b) Lateral cephalometric projection  Film at one side & beam from the other side  Disadvantages:  Doesn’t show both sides  Superimposition  Uses:  Orthognathic surgeries  Systemic disease with skull manifestation Page 5 of 29  c) Lateral oblique cephalometric  Change position of film & x-ray  Head of patient is tilted  Decreases superimposition of the right & left side of the mandible found in the true lateral Indications  For fractures of the ramus, body, condyle & coronoid processes of the mandible  Assessment for impacted third molars The radiograph techniques that resemble 2 words (postero- anterior / occipitomental / antero-posterior) d) Postero-anterior {PA} projection  The first name has the location of the x-ray cone  Cone posterior to the patient  The second name has the location of the film  Film anterior to the patient’s face The part of the body closest to the film, is usually the one  Mouth is closed that appears clearly  Shows the body, angle, ramus of mandible (no magnification in the x-ray) Indications  Detect fractures of the mandible (displacements)  Lesions such as cyst or tumor in posterior 1/3 of body & in ramus of mandible Disadvantage:  The symphysis is often obscured by the cervical spine  Condyles can be superimposed over the mastoid process & occipital bone Condylar & sub-condylar areas can not be seen using PA radiograph Page 6 of 29  e) Reverse Towne view  Modification of postero-anterior radiograph to show the condylar area  Patient tilt heads downward & opens his mouth  This shifts the condyle downward & forward so its not in the same level of mastoid process & occipital bone & decrease superimposition  The head angulation gives a magnification to the view (skull appears elongated & magnified) In antero-posterior the cone is from the anterior Indications & the film is posterior to the patient  Suspected fracture of the condylar neck  The part that appears in the x-ray is the skull  Intracapsular fracture of the TMJ & occipital bone f) Standard occipito-mental (0◦ OM)  Cone x-ray from occipital bone posteriorly  The film resting on the chin anteriorly  Orbito-meatal line (orbit to external auditory meatus) makes a 45◦ with the film  Beam directed 90◦ to the film  Shows: (skull appears circular0  Orbital cavity & infra-orbital rim  Maxillary sinus  Zygomatic bone & process Main indications: (detect the following middle third facial fractures)  Le Fort I, II, III  Zygomatic complex  Naso-ethmoidal complex  Orbital blow-out Page 7 of 29 g) 30◦ Occipito-mental (30◦ OM)  This projection also shows the facial skeleton, but from a different angle than the 0◦ OM  Enables certain bony displacements to be detected  The difference is the cone is raised to 30◦ to the film (unlike 90 of the standard OM)  This projection provides a superior view of  the malar arches & the anterior aspect of the inferior orbital margins 0◦ OM as if were looking at the patient almost at same level 30◦ OM were looking from below the patient h) Waters view  The third modification of occipito-mental radiograph, in order to obtain a view of maxillary antra (maxillary sinus) while retaining a view of the frontal & ethmoid sinuses  The difference is orbito-meatal line is 37◦ with the film, x-ray is 90◦ to the film  Appears as if were looking from below Page 8 of 29  i) Submento-vertex (base) projection (Jug Handle view)  X-ray cone submental area 90◦ to the film  Film at vertex (base of skull) Indications  Help t study destructive lesion affecting the palate, pterygoid region or base of the skill, sphenoidal sinus  Fractures of zygomatic arches (Jug Handle)  as if the zygomatic arches resemble the handles of a jug Interpretation of the different types of radiographs Identification (3 things needs to be identified)  Extra-oral or intra-oral  Name of the radiograph  Pre or postoperative (if there’s any treatment done) Care during interpretation of x-ray of:  Normal anatomic structures/variations  Compare symmetry (radiographs showing the 2 sides are better) Description of lesions  Radiolucent or Radiopaque or mixed  Well-defined or ill-defined  Single or multiple  Mono-locular or multi-locular (honey-comb / soap bubble / tennis-racket)  Shape (rounded / pear shape / heart shape)  Site & relation (same lesions are related to certain areas)  Expansion of bone, resorption of roots (in malignant tumors) , lamina dura & pdl space Page 9 of 29  Examples of lesions 1. 1) Intraoral 2) Periapical radiograph 3) Well-defined radiolucent lesion related to a badly restored lower 6 with radiopaque margin 4) Widening of PDL & lamina dura not intact 5) DD of lesion: Periapical granuloma / PA cyst / chronic periapical abscess 2. 1) Intra 2) Periapical radiograph 3) Well defined radiopaque lesion related to apex of first molar 4) No widening of PDL space & intact lamina dura 5) DD: Hypercementosis / cementoblastoma / sclerosing osteomyelitis (if non-vital)  Most probably hypercementosis as it has intact lamina dura & no widening of PDL space ` 3. 1) Intraoral 2) Maxillary occlusal radiograph 3) Well-defined radiolucent lesion related to 4 anterior teeth 4) Heart-shaped 5) DD: Nasopalatine duct cyst Page 10 of 29  To interpret fractures  check the external borders of the bone To interpret lesions  check the trabeculations of the bone of the ridges 4. 1) Extraoral 2) Panoramic radiograph 3) Well-defined radiolucent lesion related to badly restored lower right 4 4) DD: Periapical abscess/ PA granuloma / PA cyst 5. 1) Extraoral 2) Panoramic radiograph 3) Well defined radiolucent lesion related to lower right 7 4) In the angle & ramus of the mandible 5) DD: Unicystic ameloblastoma / keratocyst ` Page 11 of 29 6. 1) Extraoral 2) Panoramic radiograph 3) Well-defined multilocular radiolucencies 4) In body, angle & ramus area 5) Mixed between soap-bubble appearance & honey- comb appearance 6) DD: Multilocular ameloblastoma / Odontogenic myxoma / central giant cell lesion / hemangioma / aneurysmal bone cyst 7. 1