DENTAL IMPLANT COURSE - Modules 1+2 PDF

‫‪DENTAL IMPLANT COURSE‬‬ ‫د‪.‬غسان نازك الدعمي‬ ‫بورد عربي (دكتوراه) جراحة الوجه والفكين‬ ‫دبلوم عالي اختصاص دقيق ليزر‬  Alveolar process  The part of the maxilla that supports all of the maxillary teeth  Extends inferiorly from the maxilla  Each maxilla contains 5...

‫‪DENTAL IMPLANT COURSE‬‬ ‫د‪.‬غسان نازك الدعمي‬ ‫بورد عربي (دكتوراه) جراحة الوجه والفكين‬ ‫دبلوم عالي اختصاص دقيق ليزر‬  Alveolar process  The part of the maxilla that supports all of the maxillary teeth  Extends inferiorly from the maxilla  Each maxilla contains 5 primary and 8 permanent teeth  Alveolar bone is resorbed when a tooth is lost  Anterior AreaSurgical Anatomy - 🗌Located between the anterior walls of the maxillary sinus, this area is usually of good bone quality. The region is apically limited by the nasal cavity that communicates with the maxillary sinus (through the middle meatus). Slight penetration or perforation of the nasal floor may be uneventful. 🗌The canine region is a strategic area due to mechanical stress dispersion. 🗌The incisive foramen (continuous with the incisive canal) is located between the two medial incisors, slightly palatal. Its volume can prevent implant placement. Its content is not essential (accessory vascularization and innervation) and can be replaced by a bone graft or substitute to improve the bone bed. Posterior AreaSurgical Anatomy - Posterior AreaSurgical Anatomy Posterior AreaSurgical Anatomy -  Posterior AreaSurgical Anatomy - 🗌This region is characterized by limited bone volume (due to the presence of the maxillary sinus) and poor bone quality. 🗌The maxillary sinus is a large aerial cavity lined with a thin membrane. Slight penetration or perforation of the sinus floor in a healthy sinus can be uneventful. Posterior AreaSurgical Anatomy - 🗌Sinus lift procedures are indicated to augment bone volume in this region. This surgery is frequently complicated by the presence of septa 🗌in the maxillary sinus. Septa occur in about 30% of sinuses, and they are most commonly located in the first and second molar area. The permeability of the maxillary sinus ostium must be checked before Surgery 🗌Tuberosity and pterygopalatine region: in order to avoid the sinus region, the tuberosity can be used for implant placement. Occasionally, primary stabilization could be necessary in the suture (palatine bone-pterygoid process-maxillary tuberosity). MandibuleSurgical Anatomy - Anterior SiteSurgical Anatomy - 🗌This region is usually considered at low risk for surgical damage Anterior SiteSurgical Anatomy - However, some anatomical structures have to be identified: 🗌The incisive canal is an anterior extension of the mandibular canal with neurovascular content. The lesion of this structure usually has no clinical consequences except in the first premolar area and sometimes in the canine area 🗌The lingual foramen can be observed on X-rays or CT scan in more than 80% of subjects near the mental spines. A branch of the sublingual artery enters the foramen to supply the bone Anterior Site, Key points:Surgical Anatomy - 🗌Sublingual and submental artery (moderate risk). In the lateral incisor or canine region mandibular perforation is performed during osteotomy, resulting in potential bleeding in the oral floor and the parapharyngeal space. 🗌Elevation of the periosteum of the lingual aspect during surgery and adequate compression or ligature will prevent problems. Posterior AreaSurgical Anatomy -  Posterior AreaSurgical Anatomy - 🗌The inferior alveolar nerve enters the mandibular ramus distally through the mandibular foramen and runs in the mandibular canal, from the lingual to the labial side. 🗌 At the mental foramen (most often between the first and second premolar) it becomes the mental nerve which divides into three branches for the skin and gingiva. The mean distance between alveolar crest and superior margin of the mental foramen is about 10 mm ± 5 mm, in non edentulous areas. 🗌Occasionally, the inferior alveolar nerve describes an anterior loop Rare variations (bifid mandibular canal, multiple foramina) have been described 🗌The posterior area of the mandibular body often shows lingual concavities facing the submandibular gland. 🗌The lingual nerve runs near the inner surface of the mandible in the region of the wisdom tooth, and then has an oblique course forward and inward, down to the tip of the tongue. Posterior Area, Key Points:Surgical Anatomy - 🗌Inferior alveolar nerve (high risk): laceration or compression of the nerve in the mandibular canal or section of the anterior loop during osteotomy will result in permanent paresthesia. Precise 3D preoperative imaging (CT scan or CBCT) is thus essential in this region. 🗌Mental nerve (moderate risk): section (during dissection) or compression (with instruments) of the mental nerve can occur.This is why good visualization of the mental foramen is recommended during surgery. 🗌Lingual nerve (moderate risk): injury or compression of the lingual nerve can occur when raising a full-thickness lingual flap, if the technique is not careful enough. Oral surgery skills can be learned through the knowledge of the basic principles of surgery, knowledge of the anatomy of the region and good practical training. The main prerequisite for an operator performing surgical procedures is to ensure Asepsis and Antisepsis, to prevent pathogenic microbes from entering the body as well as spread of certain infectious diseases from one patient to another. This is accomplished through:  Sterilization of instruments involving dry heat, moist heat (autoclave) and chemical means of sterilization.  Preparation of the patient by seating the patient on the dental chair, disinfecting the skin around the mouth and the oral mucosa and covering the patient with sterile drapes.  Preparation of the operator by disinfecting the hands and wearing the appropriate sterile gown and surgical gloves. Flap is simply defined as a section of soft tissue that is outlined by surgical incisions, carries its own blood supply, allows surgical access to underlying tissues, can be replaced as required on its original position, maintained with sutures and is expected to heal. Most of the oral surgical procedures require the reflection of a full mucoperiostial flap incorporating mucosa, submucosa and periosteum to gain access to the area that is the object of surgery.  Incision It is simply defined as a cut or wound made by cutting with a sharp instrument. The basic principles of incisions in oral surgery include:  A blade number 15 is suitable for most oral surgical procedures. Sometimes a blade number 12 is used.  A new and sterile blade should be used for each patient and it should be replaced with a new one intraoperatively if its cutting edge becomes blunted when necessary.  The scalpel blade is mounted on the scalpel handle with the help of a needle holder, or hemostat, with which it slides into the slotted receiver with the beveled end parallel to that of the handle.  The scalpel is grasped in a pen grasp for maximum control and tactile sensitivity.  The incision should be made at right angle to the underlying bone to ensure good healing when the tissues are re-apposed.  The scalpel should move at uniform speed and with sufficient firmness to cut through not only the mucosal surface but also the periosteum overlying the bone. It should be made, ideally, with a single movement, repeated strokes at the same place should be avoided as they may impair healing.  Flap design The essential points that should be considered include:  Flap design and incision should be carried out in such a way that injury of anatomic structures is avoided, such as: the mental neurovascular bundle, palatal vessels emerging from the greater palatine foramen and incisive foramen, lingual nerve, submandibular duct, facial artery and vein. So thorough knowledge of the anatomy of the orofacial region is essential.  The base of the flap should be wider than its apex (free gingival margin) to ensure adequate blood supply for better healing.  The flap should be of adequate width for good visualization and accessibility of the operative field without subjecting the flap to tension and trauma during manipulation.  When planning the flap the care should be given to the fact that the flap should be wider than the anticipated bony defect after completion of the procedure so that the flap margins, when sutured, should rest on intact and healthy bone to prevent wound dehiscence and poor healing.  Delicate handling of the flap during the surgical procedure without excessive tension of crushing in order not to compromise the blood supply which leads to delayed healing.  Vertical releasing incisions should start at the buccal vestibule and end at the interdental papilla which should either be excluded or included in the flap, the incision should always pass to the interdental papilla and not end at the labial or buccal surface of the tooth to ensure the integrity of the gingiva, but it should not pass through the papilla for accurate replacement of the flap. Vertical releasing incisions are contraindicated in certain sites in the oral cavity: Transverse incisions in the palate: to avoid injury to the greater palatine artery. Lingual surface of the mandible: to avoid injury to the lingual nerve, Canine eminence. In the area of mental foramen, between mandibular first and second premolars: to avoid injury to the mental nerve.  Types of Mucoperiosteal Flaps Envelope Flaps This type of flaps is made by a horizontal incision through gingival sulcus for the teeth or through the alveolar mucosa of the edentulous area with no vertical releasing incisions. The envelope flap is used for surgery of incisors, premolars and molars, on the labial or buccal and palatal or lingual surfaces. The main indications of this type of flaps include: surgical extraction of impacted mandibular third molars, palatal approach to impacted maxillary canines or removal of mandibular tori. The main advantages of this flap are; easy re-approximation to original position, good blood supply and it can easily modified to two-sided or three-sided flap by adding vertical releasing incisions to either ends of the flap when necessary. Disadvantages of this flap are the limited accessibility and visualization, difficulty in reflection with greater tension that can result in tearing at the ends of the flap, in addition to defect in attached gingiva and the possibility of injury to the greater palatine artery during reflection of palatal flap. Two-sided Flap (Triangular Flap) This flap is the made with a horizontal incision along the gingival sulcus or alveolar ridge mucosa and a vertical releasing incision. The vertical incision begins approximately at the vestibular fold and extends to the interdental papilla of the gingiva. This flap is performed labially or buccally on both jaws and is indicated in the surgical removal of root tips, impacted teeth, small cysts, and apicectomies. Advantages are; it ensures an adequate blood supply, satisfactory visualization and accessibility, good re- approximation; it can be easily modified to a three- sided flap, or even lengthening of the horizontal incision. Disadvantages are; limited access, tension when flap is retracted and it may result in defect of attached gingiva. Three-sided Flap (Trapezoidal Flap) This flap consists of a horizontal incision along the gingival or alveolar ridge mucosa and 2 vertical releasing incisions, this flap is indicated when an extensive surgical field exposure is required especially when two-sided flap is inadequate. The main advantages include; very good accessibility and visualization of the surgical field with minimal tension on the tissue, and good re- approximation of tissue to the original position. The disadvantages are the possibility of producing an attached gingival defect. This flap cannot be lengthened or modified once reflected. Semilunar Flap This flap is the result of a curved incision, which begins just beneath the vestibular fold and has a bow shaped course with the convex part towards the attached gingiva. The lowest point of the incision must be at least 0.5 cm from the gingival margin, so that the blood supply is not compromised. Each end of the incision must extend at least one tooth over on each side of the area of bone removal. The semilunar flap is used in apicoectomies and removal of small cysts and root tips. Advantages of this flap are small incision, easy reflection, no attached gingival defect especially around prosthetic appliances (crowns and bridges) and easy oral hygiene. Disadvantages of this flap are  limited accessibility and visualization of the surgical field,  re-approximation may be difficult due to the absence of reference points,  tendency to tear due to excessive tension on reflection  the possibility that the flap may made over defective bone as a result of inadequate planning or underestimation of the size of the bony defect so that the margins of the flap will not rest on intact bone leading to collapse of the flap and wound dehiscence. Flap reflection The mucoperiosteal flap is reflected from the underlying bone using periosteal elevators. There are many any types of mucoperiosteal elevators like Howarth, Ash, the no.9 Molt, Seldin, or Freer types. The elevators should be firmly pushed at approximately 30- 45° to the surface of the bone such that the periosteum is stripped from it. It is important to try to raise both mucosa and periosteum in one layer and this requires a considerable force to be applied. Reflection of the flap begins at the papilla, the periosteal elevator is pushed underneath the papilla in the area of the incision and is turned laterally to pry the papilla away from the underlying bone. This technique is used along the entire extent of the free gingival incision. If it is difficult to elevate the tissue at any one spot, the incision is probably incomplete, and that area should be re-incised. periosteal elevator (Howarth( A dry, sterile swab can be interposed between the periosteal, elevator and the bone. The elevator may also be used for holding the flap after reflecting, facilitating manipulations during the surgical procedure. Oftentimes two elevators can be used to advantage, one working and the other aiding retraction in the subperiosteal plane. Adequate undermining of the wound margins is required in order to mobilize the flap. Generous reflection is the key to adequate vision, and wide exposure reduces traction trauma to the wound edges. Suturing After completion of the surgical procedure, thorough irrigation of the surgical field using sterile normal saline follows. Then the flap is repositioned to its original position and held in place using sutures  to protect the underlying tissues from infection and irritating factors and prevent postoperative hemorrhage.  Sutures are also used to repair soft tissue lacerations,  ligation of vessels and control of bleeding,  immobilization of flaps in their new position,  and stabilization of drains in place. Suture diameters vary from 0.02 to 0.8 mm. This corresponds to 10/0 to 5 on the British Pharmacopoeia (BP) system. The finest suture that will hold the wound secure, without it breaking should be chosen. The amount of suture material used should be kept to a minimum, particularly when braided, to reduce bacterial colonization. Suture material can be a nidus for infection, and knots can be the focus of a persistent and chronic inflammatory reaction (suture knot sinus). Suture Materials Suture materials are classified as either absorbable or non-absorbable material depending on whether the body tissues will degrade the suture material and absorb it over time. Absorption takes place either by Hydrolysis or by proteolytic enzymatic degradation depending on the material used. They can also be classified as monofilament or multifilament.  Absorbable Sutures They are used in suturing of deep layers of wounds when multilayered suturing is required, they are also used in children, mentally handicapped patients and in patients who cannot return to the clinic to have their sutures removed. They can cause inflammatory tissue reaction that can impede tissue healing. Some of the popular absorbable sutures include: Plain Catguts it is made from collagen derived from healthy sheep or cattle intestine, its tensile strength is lost within 7-10 days, its absorption is through phagocytosis and enzymatic degradation which occurs within 7-10 days producing high tissue reaction. It is used for suturing subcutaneous tissues that do not require prolonged support. It is not suitable for suturing in oral surgery. Chromic Catgut: it is made from collagen derived from healthy sheep or cattle intestine tanned with Chromium salts to facilitate handling and resist tissue degradation. It tensile strength is lost within 18- 21 days, its absorption is like that of the plain Catgut but it takes longer time and with moderate tissue reaction. It has the same indication as for the plain Catgat and it is not suitable in oral surgery. Polyglactin (Vicryl): this synthetic suture material is made of polymer of lactide and glycolide coated with polyglactin and calcium stearate. It is braided multifilament suture, 60% of its tensile strength remains for 2 weeks, and about 30% for 3 weeks. Its absorption is through hydrolysis with complete absorption taking place within 60-90 days, it induces mild tissue reaction. This suture is widely used in surgical practice but it is not advised for use where prolonged approximation under tension is required. Polydioxanone (PDS): supplied as monofilament dyed or undyed, it is made of polyester polymer, 70% of its tensile strength remains at 2 weeks, 50% at 4 weeks and 14% at 8 weeks. Absorption occurs through hydrolysis which is complete in about 180 days, it is used when slight longer wound support is required.  Non-absorbable sutures These sutures remain in the tissues and are not absorbed, but have to be cut and removed about 7 days after their placement. Commonly used sutures include: Silk: it is made of raw silk from silkworms, and it is supplied as braided or twisted, dyed or undyed, coated with wak or silicon or uncoated. 80%- 100% of its tensile strength is lost within 6 months. Fibrous encapsulation occurs in the body within 2-3 weeks, it causes moderate to high tissue reaction. It is used in ligation and suturing when long term tissue support is needed. Silk sutures are the easiest to use and the most economical, and have a satisfactory ability to make a secure knot. Nylon: it is made of polyamide polymer and it is supplied as monofilament or braided multifilament dyed or undyed. It loses 15%- 20% of its tensile strength per year. It causes mild tissue reaction and it is used mainly for skin, in plastic surgery, neurosurgery, and ophthalmic surgery. Poly propylene (Prolene): it is made of polymer of propylene and it is supplied as a monofilament dyed or undyed. It produces low tissue reaction and remains encapsulated in the tissue. It is mainly used in skin. One of the most commonly used suture for the oral cavity is 3/0 black silk. The size 3/0 has the appropriate amount of strength; the multifilament 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 be seen when the patient returns for suture removal. However, because of the multiple filaments, they tend to "wick" oral fluids along the suture to the underlying tissues. This wicking action may carry bacteria along with the saliva. Sutures that are holding mucosa together usually stay no longer than 5 to 7 days, so the wicking action is of little clinical significance. Needle Holder These instruments come in a variety of sizes and design and operators tend to choose one that suits them. In general, they have a locking handles allowing the needle to be locked into the beaks of the instrument. They resemble Hemostats but with few differences; the beaks of the hemostat is longer and thinner than that of the needle holder, also the internal surface of the short beaks of the needle holder is grooved and crosshatched, permitting a firm and stable grasp of the needle, while the short beaks of the hemostat have parallel grooves which are perpendicular to the long axis of the instrument. Tissue Forceps Sometimes known as dissecting forceps, the important requirement is that they hold the soft tissues atraumatically so avoiding crushing and with little chance of slippage. This is achieved by a toothed design in the form of a wedge-shaped projection or tooth on one side, and a receptor on the other, which fit into each other when the handles are locked, although possibly causing tiny puncture points, is ideal for the purposes of suturing and holding soft tissues generally. The use of non-toothed forceps will result in crushing of the tissues as, to prevent tissue slippage from grasp, the instrument must be held too tightly.  Principles of Incisions and Flaps in Oral Surgery Principles of suturing Suturing should be undertaken using a no-touch technique to reduce the risk of a needle-stick injury and the fewer the number of sutures used to produce the desired result, the better. Insertion of too many sutures tears the tissue unnecessarily, and the resulting tangle of suture thread tends to accumulate plaque and promote inflammation. When re-approximating the flap, the suture is passed first through the mobile (usually facial) tissue, the needle is re- grasped with the needle holder and is passed through the attached tissue of the lingual papilla. But if the two margins of the wound are close together, the surgeon may be able to insert the needle through both sides of the wound in a single pass. However, for better precision it is better to use two passes in most situations. The tissue of the flap should be held firmly by the tissue forceps and the needle passed through the mucoperiosteum about 3 mm from the margin, more if the flap is friable because of chronic infection. The needle is then pushed through the corresponding tissue on the other side of the incision, again about 3-5 mm from the margin. The needle should enter the surface of mucosa at right angle, and the passage of the needle should follow it curvature to prevent tearing of the flap. After the needle passes through both wound edges, the suture is pulled, so that the needle- bearing end is longer. Afterwards, the long end of the suture is wrapped around the handle of the needle holder twice. The short end of the suture is grasped by the needle holder and pulled through the loops. The suture is then tightened by way of its two ends, thus creating the first double-wrapped knot. Then a single- wrap knot is created, in the counterclockwise direction, which is named a safety knot.  Where possible, the knots should be drawn to lie to one or other side of the line of incision. Over-tightening of the suture, manifested by blanching of tissue, must also be avoided, it runs the risk of tissue necrosis and wound dehiscence. Overlapping of wound edges when positioning the knot should also be avoided.  Before the sutures are inserted the non-flap side of the incision should be undermined to facilitate the insertion of the needle.  Sutures placed intraorally are normally removed 5-7 days postoperatively. In the removal of sutures, normal dental tweezers should grasp the free ends of the thread and the suture should be cut by sharp scissors. The suture should then be pulled though in its entirety. The suture is better cut just as it enters the tissue to avoid pulling a contaminated suture through the tissue. Suturing Techniques Simple Interrupted Sutures This is the simplest and most frequently used type, and may be used in all surgical procedures of the mouth. The needle enters from the margin of the flap (mobile tissue) and exits at the same distance on the opposite side. The two ends of the suture are then tied in a knot. The advantage of the interrupted suture is that it is simple to execute and when sutures are placed in a row, inadvertent loosening of one or even losing one will not influence the rest. Continuous Sutures This is usually used for the suturing of wounds that are long, e.g., for re- contouring of the alveolar ridge in the maxilla and mandible. This technique for the continuous simple (or nonlocking) suture is as follows: after passing the needle through both flap margins, an initial knot is made just as in the interrupted suture but only the free end of the suture is cut off. The needle-bearing suture is then used to create successive continuous sutures at the wound margins. The last suture is not tightened, but the loop created actually serves as the free end of the suture that is used to tie the knot. The continuous locking suture is a variation of the continuous simple suture. This type of suture is created exactly as described above, except that the needle passes through every loop before passing through the tissues, which secures the suture after tightening. Suturing continues with the creation of such loops, which make up parts of a chain along the incision. These loops are positioned on the buccal side of the wound, after being tightened. The advantage of the continuous suture is that it is quicker and requires fewer knots, so that the wound margins are not tightened too much, thus avoiding the risk of ischemia of the area. Its disadvantage is that if the suture is inadvertently cut or loosened, the entire suture becomes loose.  Mattress Suture: This is a special type of suture and is described as horizontal and vertical. It is indicated in cases where strong and secure re-approximation of wound margins is required. The main indication for use of vertical mattress sutures is to evert the skin edges, the technique permits greater closure strength and better distribution of wound tension. The horizontal suture also allows eversion of the wound edges and is used in cases which require limiting or closure of soft tissues over osseous cavities, e.g., post-extraction tooth sockets. In the mattress suture the needle passes through the wound margins at a right angle, and the needle always enters and exits the tissues on the same side.  Figure of Eight suturing: occasionally placed over top of socket to aid in hemostasis, it is usually performed to help in maintaining a piece of oxidized cellulose in tooth socket after tooth extraction. Mattress suturing Figure of 8 suturing Break Types of Dental Implants Types of Dental Implants Types of Dental Implants Indication IMPLANT STATUS simply stated as follows:Modern definition of “success” A dental implant therapy is successful when there is no complication over time and when the patient is satisfied. simply stated as Modern definition of “success” follows: A dental implant therapy issuccessful when there isno complication over time and when the patient issatisfied Dental Implant Physical & Biological Consideration 🗌The compression of the bone surrounding the implant reduces the peripheral vasculature, and the lack of an adequate blood supply leads to a non-vital tissue at the bone/implant interface. 🗌The inflammatory response to the surgical injury aims to remove the damaged tissues and to initiate the healing process leading to osseointegration Osteointegration Osteointegration-Definition From Latin, ossum "bone" integrare "to make whole" is the direct structural and functional connection bone and the surface ofbetween living a load-bearing artificial implant Osteointegration-Definition 🗌 Functional ankylosis (bone adherence), where new bone is laid down directly on the implant surface and the implant exhibits mechanical stability 🗌 Formation ofa direct interface between an implant and bone, without intervening soft tissue". Factors affecting Osseointegration Factors affecting Osseointegration Implant Factors affecting Osseointegration Implant neck 🗌The initial stability of the interface between the implant and the mineralized bone is a critical factor to initiate the osseointegration process. 🗌The primary stability of the dental implant is often achieved at the cortical bone level. In the cortical compartment at the implant neck, the non-vital lamellar bone is first resorbed before new bone formation occurs onto the implant surface.` Factors affecting Osseointegration Implant body 1.Clot formation 2.Bone modeling 3.Bone remodeling Factors affecting Osseointegration 1-Clot formation The blood fills the space between the threads of the implant. Erythrocytes, neutrophils, and macrophages are trapped in a fibrin network. The fibrin clot is replaced by granulation tissue. Mesenchymal cells and blood vessels proliferate in the new granulation tissue, which is rich in collagen fibers. Factors affecting Osseointegration 2 Bone modeling A first line of osteoblasts, migrating from bone marrow, invades the granulation tissue. After one week an osteoid matrix is observed in the mesenchymal tissues surrounding the blood vessels. In the osteoid, deposition of hydroxyapatite leads to woven bone formation (immature bone). It fills the space between the implant threads, constructing the first bony bridges. This direct contact between the woven bone and the implant surface represents the first phase of the osseointegration. Factors affecting Osseointegration 3 Bone remodeling Woven bone is progressively replaced by lamellar bone and marrow (mature bone).The lamellar bone is the strongest type of newly formed bone, and the most elaborate type of bone tissue. Bone shape and quality Bone shape and quality Volume Shape Quality of the bone Bone shape and quality Bone shape and quality 🗌The volume, shape, and quality of the bone are important parameters, in establishing the treatment plan. They strongly influence the choice of surgical procedure and implant dimensions. 🗌The bone volume determines the available bone, i.e. the bone dimension that can be used for dental implant placement. 🗌The quality of the bone, i.e. the density, strength, and elasticity, may determine the ability of the bone to support the stress induced by the prosthetic restoration Bone shape and quality 🗌Several classifications have been proposed. The classification of Lekholm and Zarb (1985) is based on the residual jaw morphology and deals with the insertion of dental implants. They described five levels of jaw resorption in edentulous patients, ranging from minimal to severe osseous atrophy. Bone shape and quality  Bone shape and quality 🗌The alveolar bone loss is almost 10 times greater 3 months postoperatively than in the years following tooth extraction. 🗌The resorption is higher at the posterior maxilla than in other areas of the jaws Bone shape and quality 🗌Consequently, the mandible is designed as a force absorption unit with a dense outer cortical bone and a coarse or dense trabecular bone. 🗌The maxilla is a force distribution unit: the zygomatic arch and palate dissipate mechanical stress to protect the brain and orbit Bone shape and quality 🗌The available bone volume may be evaluated by: 🗌clinical palpation 🗌A CT scan 🗌Osseous bone density may be assessed by probing through the mucosa, under local anesthesia and/or during the implant surgical site preparation. Strong correlations have been found between tactile perception and osseous density during bone drilling.  Bone shape can be evaluated 🗌 shape and quality Bone before radiographic analysis, during the clinical examination. 🗌Bone quality cannot be evaluated during the clinical examination. Implant structures  Implant Selection A wide array of dental implants is available. Worldwide, approximately 600 different options can be chosen, although most are similar in form and surgical steps. 10 Most of the endosseous implant systems use a series of incrementally larger-diameter drills.  A good rule of thumb is to select the drills in increments of 0.5 to 1 mm; increasing the bur diameters gradually generates less heat and trauma to the osteotomy site. Slow drilling, sharp burs, chilled irrigation, and light drilling pressure all minimize temperature elevation during bone site preparation Thank you