export_jvd2014314use of composite restoration materials COPY Flashcards
Foundations: Use of Composite Restoration Materials, Ellen D. Domnick
JVD 2014 Winter 31(4) p280-288
Goals of restoration
- pain-free, functional esthetic tooth
- withstand normal occlusal forces
- retain natural tooth structure as much as possible
Preparation of the tooth to be restored
scaled supra and subgingivally, polished with non fluoride paste so as to not interfere with chemical bonding
Preparation of tooth according to Black
- resistance
- retention
- convenience
- pathology removal
- wall and preparation cleansing forms
Beveling tooth’s cavosurface margins is recommended in what class of cavity? why?
in class III - VI, greater retention strength due to greater enamel surface area and improves esthetics.
Cavity classification: Class I
Class I: pit and fissure caries
What is a Class II cavity?
Class II lesions are the extension of the Class I lesion into the proximal surfaces of premolars and molars
Class III Cavity
cavities in proximal surfaces of cuspids and incisors that do not involve the incisal edge
What is the proximal surface of a tooth?
Surface of tooth facing towards adjoining teeth in the same dental arch (mesial, distal)
Class IV Cavity
Interproximal surface to include incisal edge
-mesial/distal of anterior teeth
cavity classification class V
cavities of the gingival third of the labial, buccal, or lingual surfaces of the teeth.
Beveling of occlusal cavosurfaces in class I and II preparations is contraindicated because..
enlarges the surface area of the restorative in occlusion
What tool can be used to smooth and remove all unsupported enamel rods or undercuts secondary to pathology?
hand curette, or excavator
What type of bur can be used to remove rough edges
a round taper fine diamond bur, conical arkansas white stone bur followed by sanding discs to further smooth fractured dentin and enamel
What type of acid etch is recommended and at what concentration for dentin and enamel?
phosphoric acid is most common,
10 - 38% in dentin, 35 - 38 % in enamel
purpose of the acid etchant
- removes smear layer
- opens micropores in enamel and dentin to allow resin to penetrate
- dentin demineralized
- roughens surface of enamel
How long should enamel be etched?
dentin?
20 sec enamel
10 - 15 sec dentin
How long is the etch rinsed?
15 to 20 sec rinse to fully remove the etchant
What happens when there is prolonged drying?
flattens the collagen fibers, decreasing bond strength
Bonding agents
-liquid
-unfilled or lightly filled resins of a primer and adhesive
-Newer bonding agents combine the primer and adhesive
improve retention of restorative, prevent leakage, decrease discoloration and pulp sensitivity
How long will the bonding agent provide protection?
3 to 12 months, allowing time for the tooth to repair itself
How deep does bonding agent penetrate
200 - 400 microns
All teeth that have been sealed should be radiographed ___ to___ months post procedure
6 - 12 months, to be sure the tooth has not become infected or non vital.
Enamel and dentin composition
Enamel- 96% mineral, 4% water and organic
Dentin- 70% mineral, 30% water and organic
Cementum even softer
