Six-months Clinical Evaluation of Giomer Posterior Restorations

Objectives: The purpose of this clinical study was to evaluate the six months clinical performance of Giomer restorative system (FL-Bond II and Beautifil II, Shofu) in posterior restorations. Methods: IRB approval was obtained and consent forms were signed. 7 Class I (1 premolar and 6 molars) and 46 Class II (37 premolars and 9 molars) restorations were placed by three operators in 38 patients. All restorations were placed under rubber dam isolation and Giomer materials were used according to manufacture's instruction, and then the restorations were immediately finished and polished. Evaluations were assessed at baseline and at six months using the following modified USPHS criteria (Retention, Color Match, Marginal Adaptation, Marginal Discoloration, Anatomical Form, Surface Roughness, Surface Staining, Secondary caries, Contact, Fracture, Sensitivity) and Gingival status by the two operators. Additionally, all restorations were photographed at each evaluation and impressions were taken for SEM observations. Results: All restoration was examined after six months. Slight color change was showed in 4 cases and slight marginal change was observed in 14 restorations. The marginal change of all restorations demonstrated step irregularities when a sharp explorer was drawn across the tooth from the enamel toward the restoration interface. These marginal interfacial irregularity steps supposedly developed from chip fractures of the resin composite along the cavo-surface margin due to overfilling the composite resin onto the uncut enamel or dentin surface. Conclusions: The clinical performance of the posterior restorations placed using the Giomer materials was clinically acceptable after six months. This clinical study will continue for three years. Supported by Shofu Inc., Japan.