In vivo study of the marginal integrity of composite resin buildups after full crown preparation.
OBJECTIVE
The purpose of this in vivo study was to evaluate the marginal integrity of composite resin buildups after full crown preparation, and to identify possible changes during the provisional phase of the manufacturing process of the final restorations.


METHODS
Two test groups were determined for the use of an autocuring (Clearfil New Bond, Kuraray) and a light-curing (Optibond FL, Kerr) dentin adhesive. After rubber-dam application, both dentin adhesives were used with the total-etch technique. Then, an autocuring composite resin was applied for the core buildup. Impressions of the built-up teeth were taken directly after preparation and before cementation of the final restorations. During the provisional phase, which lasted from 7 to 28 days, the prepared teeth were restored with cemented provisional crowns. Replicas of the built-up teeth were manufactured and examined with a scanning electron microscope.


RESULTS
For the autocuring dentin adhesive, only one buildup showed a gap 10 microm wide and 100 microm long. For the light-curing dentin adhesive, two samples revealed gaps that were 10 microm wide and had lengths of 100 microm and 75 microm, respectively. No change could be perceived when comparing the state of the composite/tooth interface after preparation and before final cementation.


CONCLUSIONS
The results show that when using an autocuring composite resin in combination with dentin adhesives, nearly gap-free margins of composite buildups can be achieved and therefore might serve as a sound basis for the final restoration.
Wegner
Stefan M
SM
swegner@praxis-wegner.de
Wolfart
Stefan
S
Kern
Matthias
M
D000134:Acid Etching, Dental; D003188:Composite Resins / Q000737:chemistry*; D003442:Crowns; D000044:Dental Abutments; D003743:Dental Enamel / Q000648:ultrastructure; D003761:Dental Impression Technique; D017267:Dental Prosthesis Design; D003794:Dental Restoration, Temporary; D003804:Dentin / Q000648:ultrastructure; D017220:Dentin-Bonding Agents / Q000737:chemistry; D006801:Humans; D008855:Microscopy, Electron, Scanning; D011176:Post and Core Technique; D016628:Replica Techniques; D019279:Resin Cements / Q000737:chemistry; D013499:Surface Properties; D019246:Tooth Preparation
C029849:Clearfil Bonding Agent; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C469607:OptiBond FL; D019279:Resin Cements