Restoration of small proximal dentin lesions with the tunnel technique. A 3-year clinical study performed in Public Dental Service clinics.

The aim of this study was to evaluate the 3-year performance of tunnel restorations in Public Dental Service clinics in the county of Blekinge, Sweden. The restorations were made at the indication of a radiographically observed small proximal caries lesion extending into the outer part of dentin in permanent premolars and molars. A total of 302 restorations made by 17 dentists were evaluated 1 yr, 2 yrs and 3 yrs after placement using modified USPHS criteria. The preparations were filled with a cermet glass polyalkenoate cement (Ketac Silver, ESPE Gmbh, Germany). Evaluation was carried out by clinical and radiographical means. The percentage of successful and acceptable restorations was 92.7% after 1 yr, 89.5% after 2 yrs and 84.3% after 3 yrs. Eight % of the restorations failed due to caries, 6% fractured and 1% were replaced due to deep margin discoloration. The results indicate that tunnel restoration is a useful technique in small proximal dentin lesions in permanent premolars and molars.