Assessment of oral hygiene and periodontal health around posterior primary molars after their restoration with various crown types

Objective. To compare the time-dependent changes in oral hygiene and periodontal health after restoring primary posterior molars with a traditional stainless steel crown (SSC) or an aesthetic crown using various measures of periodontal health and oral hygiene. Design. This investigation was a randomized, non-blinded prospective controlled clinical trial in which 264 crowns of different types were fitted onto the first and/or second primary molars of 76 children. The oral hygiene and the gingival health of the restored teeth and the antagonistic teeth were evaluated clinically and radiographically at 3-and 6-month intervals for 18 months after fitting the crowns. Results. The periodontal health of the control teeth was better than that of the remaining 215 restored teeth. The oral hygiene, as measured by the simplified oral hygiene index, and gingival health, as measured by the gingival index and the volume of gingival crevicular fluid, of the restored teeth, irrespective of crown type, progressively increased during the 18-month study period. Conclusions. Oral hygiene and gingival health around a restored primary tooth deteriorate with time. Our results suggest that SSC, an open-faced SSC, or a NuSmile (R) pediatric crown should be the preferred crown type for restoring posterior primary teeth.