Short-term clinical success of posterior amalgam and composite restorations in public dental care: a multicenter retrospective study.

OBJECTIVES: This study evaluated the short-term clinical success of posterior amalgam (PAR) and composite resin restorations (PCRR) and compared their retention period (restoration age at evaluation). MATERIALS AND METHODS: Patients with posterior restorations evaluated over a mean follow-up period of 1.29 ± 0.48 years (range: 0.50–2.46 years) from public dental institutions were included. Failure was defined as fracture, anatomical form/contact mismatch, or secondary caries. Of 831 screened, 360 patients (848 restorations) met the criteria. Data were recorded; statistical significance was set at p < 0.05. RESULTS: Participants were 52.2% female and 47.8% male. Composite was used more often than amalgam (78.2% vs. 21.8%). Overall clinical success was 88.6%. Clinical success was similar for PCRR and PAR (88.8% vs. 87.6%; χ²=5.174, p = 0.075) and mean retention period did not differ (1.30 vs. 1.23 years; t = 1.458, p = 0.145). Mandibular first molars were most frequently restored/failed; fracture and secondary caries were the main failure reasons, with no statistically significant difference between materials (p > 0.05). CONCLUSIONS: PAR and PCRR showed comparable short-term clinical success with similar retention rates. The retention period should be distinguished from clinical survival, which requires standardized long-term follow-up with defect and function-based evaluation. Further studies with extended observation periods are warranted. CLINICAL RELEVANCE: Because fracture and secondary caries were the predominant short-term failure modes, improving isolation/technique, occlusal adjustment and caries-risk–based prevention—especially in mandibular first molars—may enhance outcomes in public dental settings.