BDS 11141 Endodontic Surgery PDF

BDS 11141 Endodontic Surgery Date : 25 / 03 / 2020 Aims: The educational aims of this lecture are: To explain indications and contraindications for endodontic surgery To explain the spectrum of endodontic surgery To detail how to perform an endodontic surgery Objectives: On completion of this lectur...

BDS 11141 Endodontic Surgery Date : 25 / 03 / 2020 Aims: The educational aims of this lecture are: To explain indications and contraindications for endodontic surgery To explain the spectrum of endodontic surgery To detail how to perform an endodontic surgery Objectives: On completion of this lecture, the student should have: An understanding of when an endodontic surgery can be of use An understanding of the clinical steps and outcomes of endodontic surgery Root-end Cavity Preparation: Objective: To create a cavity into which a root-end filling can be placed. In order to seal the potential avenues of communication from the resected root-end to the canal system adequately. Requirements of an ideal root-end preparation: 1. 2. 3. 4. 5. The apical 3mm of root canal must be cleaned and shaped. Preparation parallel to the anatomic outline of the pulp cavity. Adequate retention form. Removal of isthmus tissues if present. Dentin walls are not weakened. Ultrasonic root-end cavity preparation: : Developed to solve the problems of bur preparation 1. 2. 3. 4. 5. 6. Advantages: Smaller size osteotomy and better access. Less or no need for bevelling. The deepest preparation possible coincedent with pulp space anatomy. More parallel walls to the long axis for better retention. Less debris and smear layer. They are effective in the debridement and enlargement of canal anastomoses and irregularities commonly found in molar roots. However cracks in the root surface following use of ultrasonic root end preparation instruments. After root-end preparation the cavity should be irrigated with sterile saline or water. Paper points can be used to dry the preparation. The Stropko irrigator/drier device can be used.. Following drying, the cavity must be inspected to ensure that it is clean Treatment of the root face: Removal of the smear layer and exposure of the apical collagen fibres is recommended after root-end resection to: A- remove potentially contaminated debris. B- enhance the healing environment for cemental deposition. The optimal exposure of collagen and demineralization occurs with a burnishing application of citric acid (pH 1.0) for 3 minutes. Various agents have been recommended including, EDTA, tetracycline and citric acid. When mineral trioxide aggregate (MTA) is used as a root-end fillingmaterial , EDTA should not be used because it may interfere with the hard tissue– producing effect of MTA. Root-end Cavity Filling: The purpose of the root-end filling is to seal the canal system apically and prevent the egress of bacteria and bacterial products into the periradicular tissues. Requirements of an ideal retrograde filling material: Well tolerated by surrounding tissues. Adhesive or cohesive to tooth structure. Dimensionally stable. Resistant to dissolution. Promote comentogenesis Bactericidal or at least bacteriostatic. Non corrosive, does not stain tooth or periradicular tissues. Allow adequate working time, and then set quickly. Readily available and easy to handle. Radiopaque Prior to filling, the root-end cavity must be isolated to ensure moisture control. The appropriate use of vasoconstrictors will greatly reduce the blood flow in the surgical site but other supplementary agents are frequently used. 1-Bone wax ( not used anymore as any wax particles retained in the surgical site will provoke a prolonged inflammatory reaction). 2- Biocompatible collagen based products such as CollaPlug, CollaCote that can remain in the osseous cavity or be removed prior to closure. 3-Non-collagen products include Surgicel – gelfoam. Commonly used retrograde filling materials: 1. 2. 3. 4. 5. 6. 7. 8. Amalgam.( corrosion, persistence of periapical inflammation, long term failure) Zinc oxide- eugenol Gutta-percha. Glass ionomers. Cavit. Polycarboxylate cement. IRM (intermediate restorative material) ( resin modified zinc oxide eugenol) Provide Good seal, milder tissue reaction Super EBA.( ZO-E cement modified with ethoxy benzoic acid to alter the setting time and increase its strength.) 9. Mineral Trioxide Aggregate (MTA). 10. Biodentine 11. Bioceramics ( e.g endosequence root repair material ) Mineral Trioxide Aggregate (MTA): MTA placement technique: Pack the surrounding bone with a sterile gauze. Mix powder and liquid (distilled water) Carry the mix into the cavity with amalgam carrier or messing gun. Compact with micropluggers. Clean the surrounding surface with a damp gauze. Advantages of MTA: 1. Least toxic of all materials. 2. Excellent biocompatibility. 3. Hydrophilic (not affected by moisture or blood). 4. Superior sealing ability. 5. Radiopaque. Disadvantages: 1. Difficult to manipulate. 2. Longer setting time. 3. Expensive. Post Surgical Care: Following surgery tissue flap, the underside of the reflected tissue, the surrounding bone, and the periradicular bone cavity should be inspected for debris. Final inspection, cleaning and radiographic examination to check the density and depth of root end filling. Flap is repositioned, edges are approximated and sutured by interrupted, mattress, continuous or sling sutures. Gentle pressure can be applied using saline-soaked gauze to ensure correct tissue position with a minimal blood clot between the bone and tissue flap. All sutures should, ideally, be removed in 48 to 72 hours. Various Types Of Suture Materials Post Surgical Instructions: 1. 2. 3. 4. 5. 6. No violent activity or work for 24 hours. Stop alcohol and tobacco for the next 3 days. Good nutrition. A lot of liquid diet for the next few days. Do not lift up the lips or cheeks. A little bleeding and swelling are normal for the next few days. Application of ice bags on the face – 20 min. on and 20 min. off – for the next 6 to 8 hours. 7. Next day after surgery hot fomentations for 3 to 5 days. 8. Prescribed antibiotics and analgesics should be taken regularly. 9. Mouth rinsing with chlorhexidine mouth wash 3 times/day for one week. 10. Removal of sutures after 2 to 3 days. Classification Of Surgical Procedures: a. Perforation repair: mechanical/resorption b.Periodontal management i. Root resection ii. Tooth resection (hemisection/ bicuspidization). Corrective Surgery: Definition: Corrective surgery can be defined as the surgical procedure required to repair defects that occur in root or furcation areas (other than apex) as a result of mechanical or pathologic processes I- Perforative defects: 1- Resorptive 2- Iatrogenic Treatment: Sealing with biocompatible materials II - Periodontal repair: 1- Guided tissue regeneration 2 – Root resection: Root amputation Hemi sectioning Bicuspidisation I-Perforation Repair: Furcation Perforation:  initial attempt is internal, non-surgical repair.  When surgery is necessary, a buccal mucoperiosteal flap is reflected, the furcation bony defect is curetted to remove any pathologic tissue, and the perforation site is repaired. Strip perforation:  Non surgical repair is the 1st option  Surgical repair is very difficult therefore we refer to root amputation or hemisection. Midroot and apical root perforations A strip perforation that occurred during cleaning and shaping was repaired internally with MTA. Radiograph taken 9 months later shows no evidence of pathosis in the repaired area Cervical defects: Caused by caries or external resorption: 1. Does not penetrate into pulp space: Envelope flap  curettage and preparation  repair with glass ionomer. Crown lengthening or vertical extrusion may be done. 2. Penetrates into pulp space: Root canal treatment , then sealing of the defect. II - Periodontal Repair: 1)Root resection: (Root amputation, Radisectomy): Definition: It is a procedure that aims at elimination of weak, diseased root to allow the stronger ones to survive and when the remaining crown structure can be restored 1. 2. 3. Indications: Severe bone loss, or periodontal lesion around one root of a multirooted tooth. Vertical fracture of one root of a multirooted tooth. A perforating external or internal resorption of one root. Contraindications: 1. The remaining roots have inadequate periodontal – osseous support. 2. Fused roots. 3. Remaining roots can not be endotreated. 4. Poor oral hygiene. Prognosis: depends mainly on good oral hygiene and the patient must be able to perform extra procedures to prevent plaque accumulation. A- severe bone loss around the distobuccal root of the first maxillary molar was noted. B. Root canal treatment was followed by an amalgam core extending 4 mm into the distobuccal canal. C. The root was resected and a crown subsequently placed. 2- Hemisection: Is vertical , surgical division of the entire tooth from mesial to distal in maxillary molars or from buccal to lingual in mandibular molars to remove the involved root with the associated portion of clinical crown. Indications: 1. 2. 3. Difficult root amputation. The same indication for root amputation. Retaining half of a molar to occlude with the opposing molar. Contraindications: 1. 2. 3. Inadequate bony support for the retained half. Fused roots. Inability to restore the remaining half. Technique: RCT. of the retained part of the molar and permanent coronal restoration. After raising a sulcular flap without a vertical-releasing incision, hemisection is usually carried out by making a vertical cut through the crown into the furcation. This action results in complete separation of the tooth in two segments. The unsalvageable root and its coronal segment are then removed. A mandibular second molar has a fracture across the distal marginal ridge extending to the midroot level. B. An amalgam core has been placed. C. A hemisection procedure has been completed and the distal root is ready for extraction. D. The mesial half of the tooth has been retained as a bicuspid to form an occlusal stop to prevent the extrusion of the opposing maxillary molar. 3-Bicuspidization: Is the even division of the clinical crown leaving the two halves in a more favorable position for maintenance and cleanliness.  The two halves are then crowned turning this molar into two premolars. Purpose: Opening molar furcation area in a favorable situation for cleaning and maintenance in case of periodontally involved furcation areas. Regenerative Approaches in Endodontic Surgery The concept of GTR was introduced by Melcher in 1976 It is a technique that prevent apical migration of gingival epithelium and allowing tissue derived from the periodontal ligament to repopulate the space adjacent to the denuded root surface. Indications of GTR in endodontic surgery: 1. Large periapical lesions. 2. Through and through lesions. 3. Furcation involvment as a result of perforation. 4. Periapical lesion communicating with the alveolar crest (apico marginal defects). 5. Root perforation with bone loss to alveolar crest. Classification Of Surgical Procedures: Intentional replantation Replacment Surgery:(Extraction/Replantation): Tooth replantation involves extracting a tooth, correcting its deficiencies outside of the mouth, and replanting it into its original socket It has been stated that extraction/ replantation should not be suggested as a routine treatment but should be considered only as a treatment of last resort. Intentional replantation should be performed when it is the only alternative to extraction. Both Conventional And Surgical Approaches Are Helpless Indications: 1- Absolute inoperable root canal treatment in situ: a. Limited mouth opening and impossible finger instrumentation of molar teeth. b. Obstructed canals due to calcifications, Ag points, posts, or fragmented instrument. c. Oversized external oblique ridge that blocks the access. 2-Pulpless teeth with multiple perforations impossible to repair in situ. 3- Inability to perform surgery: a. Difficult access as lingual aspect of mandibular teeth b. Failed previous apicoectomy c. Risk to strategic anatomical structures d. Medical conditions problem prohibited a long surgical procedures e. A periodontal problem where removal of bone would result in untreatable periodontal condition Magnification and illumination in endodontic surgery. Visual aids such as loupes and the operating microscope provide the operator with excellent lighting and magnification. The precision Triad of Microsurgery: Procedure Traditional Microsurgery Magnification Eyes or loups Microscope (4-24X) Illumination Dental light Focused light Armamentarium Macro instrument Micro instrument Apex identification Difficult Precise Osteotomy 8-10 mm 3-4 mm Angle of bevel 45° Less than 10° Lingual root plate Easy perforation No perforation Procedure Traditional Microsurgery Dentinal exposure Many D.T exposure Few D.T exposure Isthmus identification Almost impossible Easy Retro preparation Approximate (seldom inside the canal) (Bur) Precise (always within canal) (ultrasonic) Root end filling Imprecise Precise Periodontium Danger of perio communication No danger of perio communication Suture 3-0 or 4-0 5-0 or 6-0 Healing After 1 week From 48 to 72 h. Healing success (1year) 40-90% 85-96.8% Management Of Surgical Complications: Patients may experience mild to moderate postoperative pain, swelling,ecchymosis, or infection. Postoperative pain typically peaks the day of surgery, and swelling reaches its maximum 1 to 2 days after surgery. (prophylactic NSAID therapy and a long-acting local anesthetic to reduce the magnitude and duration of postoperative pain). 1- Extraoral ecchymosis : Occurs when blood seeps through the interstitial tissues, this condition is selflimiting and does not affect the prognosis. Moist heat applied to the area, however complete resolution of the discoloration may take up to 2 weeks. Heat should not be applied to the face during the first 24 hours after surgery. 2-Bleeding: Bleeding can be controlled by applying steady pressure for 20 to 30 minutes, with a piece of moist cotton gauze or tea bag. Bleeding that persists require pressure to the area and injection of a local anesthetic containing 1 : 50,000 epinephrine as a first step. If bleeding continues, it may be necessary to remove the sutures and search for a small severed blood vessel where it can be cauterized to control bleeding. Occasionally, a patient may require hospitalization and surgical intervention to control bleeding, but this s an extremely rare event. 3- Sinus exposure: During surgical root canal procedures on maxillary posterior teeth.Postoperative antibiotics and decongestants are often recommended. When primary closure of the oral-antral communication is possible, the use of antibiotics is not indicated. Reading material: Students are advised to read details at: Students are advised to read details at: 1.Cohen`s pathways of the pulp, 11th edition, 2016, Kenneth M. Hargreaves and Louis H. Berman. (chapters 20-21) 2.Endodontic science (two volumes), 2nd edition, 2009, Carlos Estrela. (chapter24) 3.Problems in endodontics, Etiology, diagnosis and treatment, 2009, Michael Hulsmann and Edgar Schafer. 4.Endodontology, an integrated biological and clinical view, 2013, Domenico Ricucci and Jose F. Siqueira Jr. 5. Clinical endodontics, 3rd edition, 2009, Leif Tronstad. Aims: The educational aims of this lecture are: To explain indications and contraindications for endodontic surgery To explain the spectrum of endodontic surgery To detail how to perform an endodontic surgery Objectives: On completion of this lecture, the student should have: An understanding of when an endodontic surgery can be of use An understanding of the clinical steps and outcomes of endodontic surgery