Interproximal free gingival grafts after membrane removal in guided tissue regeneration treatment of intrabony defects. A randomized controlled clinical trial
The aim in this clinical investigation was to compare the clinical outcome of two different approaches when covering regenerated tissue after membrane removal in a GTR procedure. Coronal positioning of the gingival flaps was compared to the use of interproximal free gingival grafts.
Twenty-eight patients were randomly assigned to one of two treatment groups after controlling for intrabony defects and probing attachment level (PAL). Intrabony defects at least 3 mm deep were identified and were limited to interproximal areas; no furcation involvement was possible. Clinical measurements included full-mouth plaque scores, full-mouth bleeding scores, probing depth, marginal recession, and probing attachment level. Measurements were determined at the presurgical appointment (one week) and at the one-year follow-up. Intrasurgical measurements included the CEJ to the bottom of the defect and the CEJ to the most coronal of the bone crest. At surgery, Teflon membranes were positioned, secured, and the flaps coronally positioned, approximating complete membrane coverage. Membranes were removed at six weeks. The control sites were covered by the gingival flaps. The test sites received free gingival grafts consisting of an interproximal, epithelial-connective tissue portion and two disepithelialized buccal and lingual portions. The grafts extended 2 to 3 mm below the margin of the buccal and lingual flaps.
Similar amounts of regenerated tissue were noted in the two groups at membrane removal (7.6 mm SD 2.8 mm, test; 8.3 mm SD 2.3 mm, control). At one year, a mean probing attachment level (PAL) gain of 5.0 mm SD 2.1 mm was observed in the test sites (3.7 mm SD 2.1 mm, control) along with the probing depth reduction of 6.6 mm SD 2.4 mm. The difference in PAL gain between the test and the control groups was statistically significant. Although the sample size was small, the study suggests that use of free gingival grafts allowed predictable protection of the interdental regenerated tissue and improved the clinical outcome of GTR procedures as measured by the PAL gain. The free graft procedure is a possible alternative when primary closure by gingival flaps is compromised. [D.S.S.]
Cortellini P., G. Prato, and M.Tonetti J. Periodont, 66:488, 1995