Five-year results of guided tissue regeneration in combination with deproteinized bovine bone (Bio-Oss) in the treatment of intrabony periodontal defects: a case series report

The aim of this study was to report on the clinical and radiographic results 5 years following treatment of intrabony defects with guided tissue regeneration (GTR) in combination with deproteinized bovine bone (DBB) (Bio-Oss). Fifteen patients, with at least one intrabony periodontal defect with probing pocket depth (PPD)>= 7 mm and radiographic presence of an intrabony component (IC)>= 4 mm, were treated with a PLA/PGA bioabsorbable membrane. Prior to placement of the membrane, the defect was filled with DBB impregnated with gentamicin sulfate 2 mg/ml. Standardized intraoral radiographs were taken prior to treatment and at the control examinations after 1 and 5 years. At baseline, the average PPD was 9.2 +/- 1.1 mm, and the average probing attachment level (PAL) was 10.1 +/- 1.6 mm; the radiographic bone level (RBL) was 10.4 +/- 2.45 mm, and an IC of 6.2 +/- 2.3 mm was present. One year after membrane placement, treatment had resulted in a PAL gain of 3.8 +/- 1.8 mm, a residual PPD of 4.2 +/- 1.3 mm, an RBL gain of 4.7 +/- 2.0 mm, and a residual IC of 2.1 +/- 1.2 mm. At the 5-year examination, two patients did not show up, and two patients had lost the treated tooth. However, both teeth were endodontically treated, and progressive periodontal destruction might not necessarily have been the reason for extraction. At the 5-year control (11 patients), the PAL gain was 4.1 +/- 1.6 mm, and the residual PPD was 4.6 +/- 1.2 mm; an RBL gain of 4.9 +/- 2.7 mm and a residual IC of 1.8 +/- 0.8 mm were observed. Statistically significant clinical improvements had occurred between baseline and the 1- and 5-year controls, whereas there were no significant differences between the 1- and 5-year results. The results of GTR with bioabsorbable membranes in combination with Bio-Oss in the treatment of periodontal intrabony defects are basically stable on a long-term basis.