Clinical trial of cross‐linked human type I collagen as a barrier material in surgical periodontal treatment

Abstract

Abstract This study was undertaken to evaluate freeze‐dried cross‐linked human type I collagen when used as a barrier membrane for guided tissue regeneration (GTR) in periodontal surgery. 14 patients with radiographic evidence of bone loss and residual pocketing of >6 mm on bilaterally matched sites were given preliminary scaling, polishing and oral hygiene instruction before undergoing contralateral flap surgery. At the experimental sites, a collagen membrane was adapted to the root surfaces, extending from 2 mm apical to the bone crest to just subgingival, before replacing the flap and closing with sutures. The control sites underwent a similar procedure but without the placement of the collagen barrier. The experimental sites were selected at random. Plaque index (PLI), gingival index (GI), bleeding index (BI). probing pocket depth (PPD) and probing attachment level (PAL) were recorded at baseline, 6, 12 and 26 weeks post‐operatively. The bony defects were classified and furcation involvement noted. The clinical parameters were recorded by an examiner, previously assessed for accurate reproducibility of measurement, who was not the surgeon and unaware of the experimental sites. PPD and PAL were measured using a constant pressure probe localised by a soft stent. There was significant improvement in the PLI, GI and BI at both test and control sites at 6, 12 and 26 weeks compared to baseline ( P <0.001 for PLI; P <0.0001 for GI and BI) but no significant difference between these sites. Probing pocket depths were significantly reduced in both test and control sites at 6, 12 and 26 weeks post‐operatively ( P <.0001). Furthermore, the test sites demonstrated a greater reduction in PPD than the control sites. There was a gradual reduction in PAL reaching significant levels by 26 weeks ( P <0.001 for both test and control sites). There was a significantly greater gain in PAL at the test sites compared to the controls at 26 weeks ( P <0.05). This investigation shows that human collagen as a GTR membrane is beneficial in reducing PPD and producing a gain in PAL.