Marginal adaptation of ormocer-, silorane-, and methacrylate-based composite restorative systems bonded to dentin cavities after water storage.
OBJECTIVE
To assess the marginal adaptation of ormocer-, silorane-, and methacrylate-based composite restorative systems bonded to dentin cavities after water storage.


METHODS
Cylindric dentin cavities were prepared on the buccal surfaces of 45 extracted human molars after their enamel was removed. The cavities were assigned to one of three groups (each n = 15). Each group was restored with one of three composite/adhesive systems: an ormocer-based (Admira/Admira Bond), a silorane-based (Filtek P90/P90 System Adhesive), and a methacrylate-based (Tetric Ceram/Excite). Marginal adaptation was evaluated immediately after polymerization and after 1 month and 1 year of water aging and thermocycling. Evaluation was performed under a metallographic microscope by recording frequency of gap-free restorations, width of maximum marginal gap (MG), percentage length of debonded margins relative to cavity periphery (DM), and marginal index (MI = MG x DM/100). The results were statistically analyzed with two-way ANOVA and the Tukey test at α = .05.


RESULTS
None of the composite/adhesive systems examined exhibited gap-free restorations at any aging time. Marginal adaptation was significantly affected by the type of restorative/adhesive system, while water aging time had no significant effect. Silorane composite restorations exhibited the lowest MG, DM, and MI values, while methacrylate composite restorations revealed the highest values. Ormocer restorations showed intermediate values.


CONCLUSIONS
Although all examined composite systems failed to achieve gap-free margins with dentin cavities, the silorane-based system revealed the best marginal adaptation at all aging times.
Department of Operative Dentistry, Mansoura University, Mansoura, Egypt. salahmahmoud2010@yahoo.com
Salah Hasab
SH
Mahmoud
Essam El Saeid
Eel S
Al-Wakeel
D000134:Acid Etching, Dental / Q000379:methods; D002516:Ceramics / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D018772:Dental Marginal Adaptation; D003764:Dental Materials / Q000737:chemistry*; D003793:Dental Restoration, Permanent; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry*; D063225:Organically Modified Ceramics; D058105:Polymerization; D012821:Silanes / Q000737:chemistry*; D012833:Siloxanes / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; C420130:Excite cement; D008689:Methacrylates; D063225:Organically Modified Ceramics; D012821:Silanes; D012833:Siloxanes; C121818:Tetric ceram; C479084:admira; C479085:admira bond; C544925:filtek P90; D014867:Water