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Published on: July 21, 2014
A comparative study of bonded and non-bonded amalgam restorations in general dental practice
1Amblecote Dental Care, 181 Amblecote Road, Brierley Hill, West Midlands, DY5 2PR. paul@amblecotedental.co.uk
Objective:
This study compared the performance of non-bonded and bonded amalgam restorations in a general dental practice.
Materials And Methods:
A retrospective cohort study was carried out in a general dental practice of amalgam restorations, placed by a single operator. Non-bonded amalgam restorations were analysed over a ten-year period and bonded amalgam restorations over a five-year period. Survival analysis using the Kaplan-Maier method was carried out and an analysis of postoperative sensitivity and reasons for failure.
Results:
Each group consisted of 231 restorations in 135 patients. Survival rates of non-bonded amalgam restorations were 72.2% over five years and 51.0% over ten years. The survival rate for bonded amalgam restorations was 85.0% over five years. The difference was significant (p <0.0001, 95% CI 1.510-3.226). Analysis of postoperative sensitivity and reasons for failure were inconclusive.
Conclusion:
Within the limitations of the study, bonded amalgam restorations demonstrated greater longevity over non-bonded amalgam restorations and offer significant benefit to patients. Clinicians may feel confident to offer bonded amalgam restorations for their patients as a better alternative than non-bonded amalgam restorations.
