Clinical Evaluation of Direct Cuspal Coverage With Posterior Composite Resin Restorations
Deliperi S, Bardwell DN. J Esthet Restor Dent. 2006;18(5):256-267.
BACKGROUND: Composite resins have esthetic properties; they join the ability to preserve and reinforce sound tooth structure. Conservation is becoming popular for both small to medium defects and more compromised teeth. PURPOSE: This study aimed to evaluate the clinical performance of Class II cuspal coverage direct composite restorations. MATERIALS AND METHODS: Twenty patients, 18 years or older, were included in this clinical trial, restoring 25 vital molar teeth with one or two missing cusps. Criteria for inclusion were two or three surface restorations, replacement composite and amalgam fillings (secondary decay, fracture of either filling material or tooth structure, esthetic considerations), or virgin teeth with decay undermining a cusp. Teeth with residual cavity walls less than 1 mm or with complete loss of the clinical crown were excluded. Teeth were restored using a combination of Ultra-Etch 35% phosphoric acid, PQ1 adhesive sytem, and Vit-l-escence microhybrid composite resin (Ultradent Products, Inc., South Jordan, UT, USA). The enamel peripheral skeleton of the restoration was built up first, followed by dentin and enamel occlusal stratification. Wedge-shaped increments of composite resin were placed and cured using the variable intensity polymerizer (VIP) light (Bisco Inc, Schaumburg, IL, USA) through a combination of a pulse and progressive curing technique. RESULTS: All 25 restorations were evaluated at 6-month intervals during the 30-month period using a modified US Public Health Service (USPHS) criteria by two independent evaluators pre-calibrated at 85% reliability. No failures were reported and alpha scores were recorded for all parameters. Statistical analysis was performed using a Chi-square test (c2 ) and the Fisher’s exact test. Sixteen of the 25 samples (64%) exhibited preoperative sensitivity to air (c2 = 10.6; p = 0.001). A significant difference in tooth sensitivity was reported after completion of the restorations. No teeth exhibited sensitivity both at the 2-week recall and the 30-month follow-up (c2 = 23.5; p < 0.0001). CONCLUSION: Microhybrid composite resin demonstrated excellent clinical performance in direct cuspal coverage at completion of a 30-month evaluation.
Teeth needing large cusp replacement restorations are usually treatment planned for indirect laboratory-fabricated composite resin, ceramic, metal, or porcelain metal restorations (onlays or crowns). There have been clinical studies reporting on the longevity of direct and indirect composite resin restorations that have demonstrated no significant difference in clinical differences. There has been a shift in trends from the use of amalgam to the use of an adhesive composite resin when restoring posterior teeth. The clinical success of posterior composite resins for restoring routine preparation size has been reported to be an amalgam alternative.1 This well-designed and well-executed clinical study provides insight into the performance of direct-placement composite resin used for reconstruction of molar teeth with missing cusps. The findings clearly demonstrate the success of these composite-resin restorations. Also, using the restorative protocol described in the Abstract, the teeth remained sensitivity-free throughout the study. Based upon the study results, cuspal-coverage composite-resin restorations that are directly placed in a single visit can be considered a viable alternative to conventional indirect restorations.
1. Statement on posterior resin-based composites. ADA Council on Scientific Affairs; ADA Council on Dental Benefit Programs. J Am Dent Assoc.1998;129(11):1627-1628.
Howard E. Strassler, DMD