Coronal Access Cavity Preparation PDF

1-Objectives of access cavity preparation 2- Principles of coronal access cavity preparation 3- Guidelines For access cavity preparations 4- Access cavity preparations(Anterior &Posterior teeth) 5- Access related errors 1- Identify major objectives of access preparation in both anterior and poster...

1-Objectives of access cavity preparation 2- Principles of coronal access cavity preparation 3- Guidelines For access cavity preparations 4- Access cavity preparations(Anterior &Posterior teeth) 5- Access related errors 1- Identify major objectives of access preparation in both anterior and posterior teeth. 2-Describe why straight-line access is critical. 3-Explain the importance of pulp horn removal in anterior teeth. 4- Relate reasons and indications for removing caries or restorations during access preparation. 5- Describe the procedure, burs used, and sequence of operations to start and complete access preparations on various teeth. The objectives of access cavity preparation Topic / Subject ACCESS OPENING Advantages for having 4 walls. Principles of coronal access cavity preparation Topic / Subject I. Outline form II. Convenience form III. Removal of remaining carious dentin and defective restorations IV. Toilet of the cavity(Cleansing of the Cavity) I. Outline form To achieve proper outline form, three factors must be considered  The of the pulp chamber  The of the pulp chamber  The position and curvature of individual root canal Factors must be considered II. Convenience form  It is the form given to the access cavity to improve and of the root canal by providing a traight ine ccess ( ) from the occlusal surface the apical foramen. Convenience form IV. Toilet of the cavity Long blade endodontic spoon excavators NaOcl Emphysema Guidelines For Access Cavity Preparations Endodontic explorer Micro-Openers ENDO-MICROSCOPE LOOPS WITH LIGHT  A proper access cavity generally has with its widest dimension at the Armamentaria  Ultrasonic unit and tips Endodontic spoon Endodontic explorer # 2, 4, 6 round carbide  can be used, starting with smaller sizes and progressing to the larger sizes. Anterior Access Cavity  After visualization of the likely evaluation of the.  Caries typically is removed , the pulp chamber is entered. the risk of contamination Prevent from contaminating the pulp chamber the root canal(s)  Permits Prevents restorative fragments from becoming in the root canal system Evaluate Clinicians were about more likely to fractures, caries, and marginal breakdown if restorations were removed - For the incisors, the outline form of the cavity is in shape with its base towards the incisal edge its apex towards the cingulum. - For the canines, the outline form is in shape in  Complete roof removal is confirmed with a operative explorer if no “ ” are discovered.  The endodontic can be used to detect any overhanging walls that should be then removed till the explorer can be placed into the canal. Lingual Shoulder  Straight-line access is evaluated by inserting into the canal the that fits to the The orifice and coronal canal must be evaluated for a Rough or irregular margins can contribute to through a permanent temporary restoration Anterior Access Cavity Posterior Access Cavity  emoval of Caries and Permanent Restorations Initial External utline Form enetration of the pulp chamber roof Complete oof removal Identification of all canal rifices Removal of the cervical dentin ulges and orifice and coronal flaring traight-line access determination isual inspection of the pulp chamber floor efinement and smoothing of the restorative margins  The discussion of caries and permanent restoration removal presented in the previous section, Anterior Access Cavity Preparations, applies to posterior teeth In maxillary premolars In mandibular first premolars( ): Mandibular second premolars ( ): The initial distal boundary for maxillary molars is the oblique ridge. The initial distal boundary for and mandibular molars is a line connecting the buccal and lingual grooves. The mesial boundary for both the maxillary and mandibular molars is a line connecting the mesial cusp tips. Maxillary molar point of entry Mandibular molar point of entry  MAND MOLARS MAX MOLARS  #2 round bur for premolars  #4 round bur for molars -In the penetration angle should be toward the  The goal is the corners of the access cavity directly into the orifices.  It can be set on the pulp floor and the entire axial wall shaped at one time.  Ideally, the orifices are located at the corners.  Internally, the access cavity should have all orifices positioned entirely on the pulp floor and should not extend into an axial wall.  Extension of an orifice into the axial wall creates a mouse hole effect. Correct orifice position mouse hole effect  Law of Centrality  Law of Concentricity  Law of Cementoenamel Junction  Law of Color Change  Law of Symmetry  Law of Orifice Location  The of the pulp chamber is always located in the of the tooth at the level of the.  The of the pulp chamber are always concentric to the external surface of the tooth at the level of the.  The from the external surface of the clinical crown to the wall of the pulp chamber is throughout the circumference of the tooth the level of the.  The pulp chamber floor is always in color than the walls.  The orifices of the root canals are always located at the junction of the walls and the floor.  These bulges can be removed with safety- tip diamond or carbide burs or Gates- Glidden burs. Access cavity in maxillary molar Files must have to the apical foramen  As discussed in anterior teeth  The restorative margins should be refined and smoothed to minimize the potential for coronal leakage. -If above the PDL , It Is recognized by leakage. -If into the PDL , bleeding into the access cavity is first indication. NB: To confirm, place a file , a radiograph will show that file is not in the canal. Correction: -Perforation above the alveolar crest can be repaired intracoronally using restoration as GIC -Perforation into the PDL should be repaired as soon as possible with a good sealing repair material as MTA Prognosis depend on :  Size  Location  Periodontal condition  Length of time  Accessibility  Conclusion - Remember the portions of the tooth that must be removed to attain straight-line access to the canals. - Describe the procedure, burs used, and sequence of operations to start and complete access preparations on various teeth. -Diagram the outline form of the access preparation for all teeth. (CHAPTER 7) Tooth Morphology and Access Cavity Preparation PAGES : 136-222 Thank You