The effect of crown receipt on measures of gingival status

Although the association between crown margins and increased inflammation and probing depth is well-established, studies examining these effects have been largely post hoc. Change in gingival status measures due to receipt of crowns may affect longitudinal evaluations in clinical trials and epidemiological studies. This study examined the effects of receipt of crowns on the periodontal health of the Ramfjord index teeth. Gingival status descriptors included measures of plaque, gingival inflammation, calculus, probing depth, and gingival recession. Changes in periodontal status scores (1987-89) for teeth receiving crowns among 67 patients were compared with change in scores for teeth not receiving crowns. Teeth that were crowned showed small, but significant, differences. These teeth had greater decreases in calculus scores for both surfaces, increases in inflammation compared with decreases for teeth not receiving crowns, and increased facial probing depths. Change in gingival recession was markedly decreased on facial surfaces among teeth receiving crowns. The results suggest that crown status should be recorded routinely in clinical trials involving gingival status, and that teeth receiving crowns during the course of the study should be eliminated from the analyses.