Periodontal Regeneration of Human Infrabony Defects. II. Re‐Entry Procedures and Bone Measures

This paper evaluates the osseous healing response of 40 infrabony defects treated with guided tissue regeneration. The selected sites presented with deep periodontal lesions with a 1-, 2-, and 3-wall combination infrabony component of 6.1 +/- 2.5 mm. Baseline intrasurgical clinical measurements were compared with intrasurgical clinical measurements obtained at the 1 year surgical re-entry. A significant regeneration of bone of 4.3 +/- 2.5 mm was observed, along with a 0.4 +/- 1.9 mm resorption of the alveolar bone crest, which resulted in a 4.7 mm reduction of the original infrabony defect. Almost 90% of the sites showed a bone gain of 2 mm or more, while no site lost supporting bone; 73 +/- 31.2% of the original defect was filled with bone. The 3- and 2-wall components were filled 95 +/- 6.2% and 82 +/- 18.7% of their original depth, respectively; however, the 1-wall component was filled only 39 +/- 62.4%. It is concluded that treatment of infrabony defects according to the principles of guided tissue regeneration and a strict plaque control regimen resulted in clinically significant and highly predictable bone regeneration.