Dimensional changes in free gingival grafts at implant sites in the reconstructed mandible: a retrospective study

Abstract

Objective: To evaluate the dimensional changes in free gingival grafts (FGG) at implant sites in mandibular reconstruction patients. Methods: Patients who received FGG 4 months after implant placement in the reconstructed mandible with no keratinized mucosa (KM) present were invited for re-examination after 36.7 ± 16.8 months (3.06 ± 1.4 years). Immediately after graft extraction (T0), graft width (GW), graft length (GL), graft thickness (GT), graft dimension (GD), and vertical bone height were documented. Re-examination (T1) included clinical examinations (GW, GL, GD, peri-implant probing depths, and modified Sulcus Bleeding Index), radiographic examination (marginal bone level), and medical chart review. Results: Twenty patients and 62 implants (47 in fibula flaps and 15 in iliac flaps) were included. A significant decrease in GW (51.8%), GL (19.2%), and GD (60.2%), were found between T0 and T1 (p <.001). The univariate analysis showed that GW change was not significantly associated with reconstruction technique, baseline GL, baseline GT, baseline GD, implant location, or type of prosthesis. Implant survival rate of 100% was observed at follow-up. Conclusions: Within the limitations of the study, free gingival grafts at implant sites in the reconstructed mandible undergo dimensional change that result in a reduction of approximately 60% of the original graft dimension. Graft width decreased over 50%. Clinical relevance: FGG is the standard of care intervention for increasing the amount of KM around implants. This study was the first to evaluate the dimensional change in FGG at implant sites in mandibular reconstruction patients after a medium-term follow-up. Clinical trial registration: Clinical trial registration is not applicable as this study comprehends a retrospective analysis.