Abstract
This study was undertaken to obtain long term clinical evaluation of posterior composite resin restorations on young permanent molars.
47 decayed permanent molars of 6-13 year old children were treated with Clearfil Posterior (Kuraray) and examined at baseline, and 1,3,6,12,18, and 24 months after restorations.
At each examination, clinical assessments, color slide photos, and replications of the restored teeth were obtained, so that serial changes of the restorations were able to be observed using these replicas with SEM, etc. Findings were as follows.
1. Marginal fractures were observed in 10 cases (21.3%) during 24 months. Nine of them were simple fractures caused by excess resin overfilled beyond the margin. They seem to have encountered no difficulties by re-polishing the fracture ends. But in one case, the fracture extended inside the prepared cavity and gradually increased its extent.
2. Secondary caries were observed in 6 cases (12.8%) during 24 months. They resulted from the remaining infected dentin at the restoration in one case, and from the fractured edge of the resin in another case.4 other cases were due to insufficient extension of the preventive cavity preparation at the fissures.
3. Partial falling out of the resin body was found in one case. It seemed a gradual falling out was observed from the defectve part because of air bubbles mixed in by mistake at the restoration.
4. At 12-months, one case showed hypersensitivity to cold, and another case mastication pain, but they were very mild and showed no discomfort at 18-months.
5. In two cases, marginal coloring were observed, resulting from secondary caries in one case, and pigmentation of some stain at surface indentation.
6. In conclusion, Clearfil Posterior functioned well at the 24th-month evaluation. Also most of the clinical troubles seemed to have resulted from inadequate technique rather than material problems.
