Proximal restoration increases the risk of clinical attachment loss

To estimate the effect of proximal direct restorations in the adjacent periodontal tissues in adults from a birth cohort.

A representative sample (n = 539) of all 5,914 births occurring in Pelotas, Brazil in 1982 was prospectively investigated, being clinical attachment loss (CAL), probing depth (PD), and bleeding on probing (BOP) assessed at 31-year old. For each site, tooth surface was evaluated as sound or restored, being the restoration extension (subgingival or supragingival) and restoration material (composite and amalgam) considered. Covariables included family income, untreated caries, and service utilization patterns during life course. Multilevel Poisson regression models were used, considering three levels of variables organization: periodontal site, dental, and individual level.

Among the 28,796 periodontal sites evaluated, CAL and PD ≥ 4 mm was observed in 1.5% and 4.8%, respectively. Multilevel models showed that proximal restorations had a significant effect on CAL and PD. Subgingival and amalgam restorations showed greater effect when compared to supragingival and composite restorations, respectively.

The present study partially supports the hypothesis that proximal restorations are associated with the presence of periodontal damage. Although not indicative of disease, a significant increase was observed in CAL and PD at restored sites.