Randomized control trial of composite cuspal restorations: five-year results.

Area of Science:

• Dental Materials Science
• Clinical Dentistry
• Restorative Dentistry

Background:

• Direct and indirect resin composite restorations are common for restoring lost tooth structure.
• Evaluating the long-term clinical performance of these techniques is crucial for evidence-based practice.

Purpose of the Study:

• To compare the five-year clinical performance of direct versus indirect resin composite restorations for replacing cusps in maxillary premolars.
• To assess survival rates and modes of failure for both restorative techniques.

Main Methods:

• A randomized controlled trial involving 157 patients and 176 restorations (92 direct, 84 indirect) on maxillary premolars with Class II cavities and one missing cusp.
• Restorations were placed by two operators following a strict protocol, with random assignment of treatment technique and operator.
• Kaplan-Meier survival analysis was used with reparable and complete failure as endpoints over a minimum 4.5-year follow-up.

Main Results:

• The five-year survival rates were 86.6% for reparable failure and 87.2% for complete failure.
• No statistically significant differences were found between direct and indirect restorations for either reparable failure (89.9% vs. 83.2%) or complete failure (91.2% vs. 83.2%).
• The predominant mode of failure for both techniques was adhesive failure.

Conclusions:

• Direct and indirect resin composite restoration techniques demonstrate comparable clinical performance over a five-year period.
• The choice between direct and indirect techniques may not significantly impact long-term outcomes for restoring missing cusps.
• Further research may explore factors influencing adhesive failure modes in these restorations.