Class V Cavity Preparation Alaa Sabrah BDS MSD

ﺑﺴﻢ ﺍﻟﻠﻪ ﺍﻟﺮﺣﻤﻦ ﺍﻟﺮﺣﻴﻢ Class V Cavity Preparation Alaa Sabrah, BDS, MSD, Ph. D 9 Feb, 2014

Goals and Objectives 1. 2. 3. 4. 5. What is the definition of Class V cavity? Identify the different types of Class V cavity Preparation? Compare the designs and retention forms for the different types of Class V cavity Preparation? Discuss the different factors affecting restorative material selection for class V cavity preparation? Describe the clinical technique for treating Class V carious lesion? Sturdevant's Art and Science of Operative Dentistry (5 th Edition)

Definition �Class V- located in the gingival 1/3 of facial and lingual tooth surfaces.

Clinical Technique 1. 2. 3. 4. 5. 6. Anesthesia (Pt comfort, decrease salivary flow). Shade selection (teeth are darker cervical. Y). Isolation (visibility, expose the margins). Tooth preparation. Pulp Protection. Restoration. Laurie St-Pierre, 2014

Isolation 212 ISOLATION RETRACTION CORD AND COTTON

212 RETAINER PLACEMENT � Check 212 retainer �Need to use modified type �Can modify with heat to correct shape � Most can be ordered modified � Facial beak of 212 retainer should be more cervically placed than lingual beak

212 RETAINER PLACEMENT � Punching holes for 212 � The hole for the 212 retainer should be placed 2 -3 mm facial/buccal to the other holes

212 RETAINER PLACEMENT �GUIDE FOR PLACING 212 RETAINER �Place rubber dam with posterior retainer �Seat 212 retainer �may need to hold in place �Stabilize 212 retainer with compound

212 RETAINER PLACEMENT � PLACE BUCCAL BEAK AT LEAST 1. 0 mm FROM CERVICAL MARGIN OF LESION

Tooth Preparation for carious lesions Class IV Conventional Beveled Conventional Modified Conventional

Tooth Preparation for carious lesions � Indication: Restoring the portion � � External wall Axial wall � of a cavity that partially or entirely on root surface. Or a cavity on the crown that need to be restored with amalgam. Why? More retention and resistance needed. Design: Butt Joint margins. F and L Cavosurface margin=90˚ Gingival floor ┴ long axis of the tooth. Uniform depth.

Tooth Preparation for carious lesions � Preparation guidelines �Outline form: Kidney bean shaped, within mesial and distal line angles �Initial depth 1 mm at occlusal and 0. 75 mm at gingival �Burs: �#700, 701, 271, No. 1 Or No. 2 round bur For preparation

Tooth Preparation for carious lesions �Preparation guidelines �Initiate prep with high speed handpiece �Watch axial wall contour and depth of prep. �Axial wall should follow the original contour of the facial surface

Tooth Preparation for carious lesions � Preparation guidelines �Watch angulation of bur: keep perpendicular to external surface �Watch depth of preparation �Rounded internal line angles, smooth prep, clean margins.

Tooth Preparation for carious lesions � Preparation guidelines: Auxiliary retention placed at: �Cervical & incisal walls at junction of axial wall �Half the depth of the #1/4 round bur �DO NOT direct axially

Tooth Preparation for carious lesions � Indication: restoration of large carious lesion or replacing defective restoration in the crown intended to be restored with composite. � Why? More retention/resistance are needed � Design: some beveled enamel margins with conventional wall design. � Cavosurface margin=45˚ on beveled, 90˚ on non beveled margins. � External walls ┴ enamel surface � Uniform depth.

Tooth Preparation for carious lesions � Indications: small and moderate lesions or faults designed to be as conservative as possible in the crown � Why? All enamel margins � Design: No specific shape � Cavosurface margin ≥ 90˚ � External walls = no shape. � Only include caries or defective restoration.

Tooth Preparation for Non carious cervical lesions �Abrasion �Erosion �Abfraction

Tooth Preparation for Non carious cervical lesions �Restoration depends on: Caries (if present cavity should be restored unless incipient). 2. Gingival health (If causing plaque accumulation, then restore). 1. Aesthetic (if in aesthetic area then restore). 4. Sensitivity (if sensitive tooth then restore). 5. Pulp protection (If deep lesion then restore). 6. Tooth strength (If the lesion weaken the tooth the restore 3.

Tooth Preparation for Non carious cervical lesions �Cavity preparation: Only roughening the internal walls with diamond bur. 2. Bevel enamel margins. 3. Place grooves if more retention is required. 1.

Pulp Protection � Place calcium hydroxide in deep caries on the axial wall. � Add RMGIC linear to protect the calcium hydroxide from being dissolved by Acid etch application.

Restorative material Selection � Aesthetic � Caries activity � Access to the lesion � Moisture control � Patient age �Amalgam: if isolation is a problem �Glass ionomer: bonds to tooth structure, less prepping necessary, releases fluoride �Composite resin: esthetic