Tissue healing under provisional restorations with ovate pontics: a pilot human histological study

STATEMENT OF PROBLEM: Ovate pontics mimic the natural tooth contour and provide an esthetic result however, few studies have evaluated the histological changes in underlying tissues. PURPOSE: The purpose of this pilot study was to histologically evaluate the healing of gingival tissues in contact with provisional ovate pontics after 2 weeks. MATERIAL AND METHODS: Three patients requiring fixed partial dentures participated in this study. The provisional restorations consisted of a fixed partial denture having 2 ovate pontics: one in acrylic resin (Jet), with an ovate shell made of low-fusing ceramic (Duceram LFC); the other made completely of the same acrylic resin (control). After 2 weeks, biopsies of the gingival tissues beneath the pontics were retrieved for histological examination, and immunohistochemistry for evaluation of the vascular endothelial growth factor (VEGF) was performed. Data were analyzed using descriptive statistics. RESULTS: Clinically, all of the ovate pontic-prepared sites showed partial healing. Histologically, the thickness of the entire mucosa was similar in both specimens; however, in some regions, the epithelium presented ulcerations that were generally deeper and more frequent in control sites than in test sites. Immunohistochemical results showed that tissues beneath LFC pontics seemed to be less inflamed since they demonstrated a lower expression of VEGF (10.7 +/- .8) compared to those beneath acrylic resin ovate pontics (33.9 +/- 2.5). CONCLUSION: This pilot study demonstrated that the placement of provisional LFC ovate pontics may be advantageous for the reparative processes of the underlying tissues.