Restoration deterioration related to later failure

Area of Science:

• Dental Materials Science
• Restorative Dentistry
• Clinical Dental Research

Background:

• Dental restorations like amalgams and resin composites are crucial for oral health.
• Understanding factors predicting restoration failure is essential for improving longevity and patient outcomes.
• Previous studies have explored various deterioration signs, but a comprehensive analysis linking them to failure modes is needed.

Purpose of the Study:

• To investigate the relationship between clinical signs of deterioration and subsequent failure in a large cohort of dental amalgams and anterior resin composites.
• To identify specific predictive factors for failure in each restorative material type over an extended observation period (up to 16 years).

Main Methods:

• Longitudinal study analyzing a large number of dental amalgam and anterior resin composite restorations.
• Systematic assessment of clinical factors (e.g., surface tarnishing, marginal fracture, staining, roughness, color mismatch) as potential predictors of failure.
• Categorization of failures into true failures directly related to the restorative material.

Main Results:

• True failures occurred in 7.5% of amalgam and 30.4% of composite restorations.
• For amalgams, surface tarnishing was significantly associated with failure.
• For composites, surface roughness, marginal fracture, and color mismatch were significantly associated with failure.
• Marginal and surface staining were not significant predictors for either material type.
• Many restorations deemed unsatisfactory continued functioning for 2.5–3.5 years before replacement, often for non-material-related reasons.

Conclusions:

• Deterioration signs have varying predictive value for amalgam and composite restoration failures.
• Surface tarnishing is a key indicator for amalgam failure, whereas composites are more susceptible to failure linked to surface texture, marginal integrity, and aesthetics.
• A clearer definition of 'unsatisfactory' restorations is needed, focusing on adverse dental health effects rather than solely material degradation.