The influence of intracrevicular crown margins on gingival health: Preliminary findings

Statement of problem. The effect on gingival tissue of various crown materi als in combination with different abutment biomaterials should be investiga ted. Purpose. This in vivo study determined the gingival health and subgingival levels of periodontal inflammation-associated bacteria adjacent to various crown and abutment material combinations. Material and methods. Patients in the study received 1 of 5 treatments: an all-ceramic crown luted to a natural tooth, a metal-ceramic (titanium) crow n luted to natural tooth, a metal-ceramic thigh noble alloy) crown luted to natural tooth, an all-ceramic crown luted to a titanium implant abutment, or a metal-ceramic thigh noble alloy) crown luted to a titanium implant abu tment. Plaque was collected at least 6 months after luting by paper point f rom the gingival sulcus of each crown and an adjacent unrestored (control) tooth. DNA. probe analysis was performed to determine the levels of Porphyr omonas gingivalis, Prevotella intermedia and Actinobacillus actinomycetemco mitans. In addition, plaque, gingival redness, swelling, and bleeding score s were recorded with use of the California Dental Association scale. Statis tical analysis was used to determine the effect of restoration/abutment typ e on levels of the bacterial species and clinical parameters pertaining to gingival health. Results. None of the sulci sampled contained detectable levels of the 3 bac teria. Plaque levels and gingival redness, swelling, and bleeding scores we re low All treatment groups had similar soft tissue response as measured by gingival redness, swelling, and bleeding. Plaque scores from all-ceramic c rown/implant abutment sites were higher than plaque scores from all-ceramic crown/natural tooth sites. However, differences between experimental and c ontrol sites within the same treatment group were not observed (P>.05) with any of the 4 clinical measures. Conclusion. In patients with suitable oral hygiene, tooth-supported and imp lant-supported crowns with intracrevicular margins were not predisposed to unfavorable gingival and microbial responses.