Dyract versus Tytin Class II restorations in primary molars: 36 months evaluation

Due to the changed treatment approach of proximal caries and the amalgam controversy, clinicians are in search for new materials. The aim of the present study was to compare amalgam with an adhesive material in deciduous molars in a clinical, split-mouth design study. At baseline 30 polyacid modified composite (Dyract) and 30 amalgam (Tytin) restorations were placed in primary molars, of which 24 and 17 could be evaluated after 24 and 36 months, respectively. Modified USPHS criteria were used for clinical evaluation every 6 months. Annual bite-wing radiographs were taken for evaluation of recurrent caries and cervical gap formation. In the present study, for Dyract as well as for Tytin restorations, low rates of recurrent caries were found, while Dyract restorations showed a better marginal adaptation and surface texture compared to Tytin restorations. In the Dyract group more radiolucencies were found at baseline. In both groups no patient complaint or pain was reported related to the radiolucencies. After 3 years the colour of Dyract was not comparable to the original. For Dyract no excessive wear was noticed compared to enamel. During the study one Dyract (recurrent caries: 18 months) and two Tytin (pulpal aetiology: 6 months, recurrent caries: 36 months) restorations had to be replaced. Even though the restorations were placed in caries risk children, at the 36 months' evaluation of this clinical study, the results indicate that Dyract can be an alternative for Tytin in the primary dentition.