Three-year evaluation of computer-machined ceramic inlays: influence of luting agent.
OBJECTIVE
Changes in the occlusal marginal adaptation of computer-machined inlay restorations were assessed over 3 years.


METHODS
Each of 21 patients received two Cerec (Vita Mark II) two- or three-surface restorations, with margins entirely in enamel, placed using two of four luting agents: a homogeneous microfilled resin composite, a fine hybrid composite, a relatively coarse hybrid composite, and an encapsulated glass-ionomer cement. Replicas of the restorations were made at baseline 6 months or 1 year (93% of original restorations), 2 years (79%), and 3 years (83%). The percentage of continuous margin on the occlusal margin was evaluated for the enamel-luting agent and luting agent-porcelain interfaces using a scanning electron microscope.


RESULTS
Mean continuous margin values were high for all groups at the enamel-luting agent interface; there were no significant differences among the luting agents. For each luting agent, the percentage of continuous margin decreased significantly at the luting agent-porcelain interface over 3 years; differences among the luting agents at 3 years were not significant (Kruskal-Wallis test). After 3 years, the wear of the luting agents was significantly different. The least wear occurred with the microfilled resin composite; the coarse hybrid composite showed the most wear.


CONCLUSIONS
The occlusal margins of Cerec inlays exhibited consistently high-quality adaptation at 3 years. The microfilled resin composite luting agent was more wear resistant than the hybrid composites and the glass-ionomer cement.
Zuellig-Singer
R
R
Department of Conservative Dentistry, University of Sydney, Australia.
Bryant
R W
RW
D017438:Bisphenol A-Glycidyl Methacrylate; D002484:Cementation; D002516:Ceramics; D003188:Composite Resins / Q000737:chemistry; D017076:Computer-Aided Design; D003738:Dental Cements / Q000737:chemistry; D018772:Dental Marginal Adaptation; D019554:Dental Restoration Wear; D005069:Evaluation Studies as Topic; D005899:Glass Ionomer Cements; D006801:Humans; D007284:Inlays; D008277:Magnesium Oxide; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D011076:Polycarboxylate Cement; D018709:Statistics, Nonparametric; D015034:Zinc Oxide
D003188:Composite Resins; D003738:Dental Cements; D005899:Glass Ionomer Cements; D011076:Polycarboxylate Cement; C069103:Dual Cement; C072541:Duo Cement; C074543:Cerec; C087243:CR Inlay Cement; D008277:Magnesium Oxide; D017438:Bisphenol A-Glycidyl Methacrylate; C040235:Ketac-cem; D015034:Zinc Oxide