Clinical trial of cross-linked human type I collagen as a barrier material in surgica1 periodontal treatment
The aim of this study was to evaluate freeze-dried, cross-linked human type I collagen when used as a barrier membrane for guided tissue regeneration in periodontal surgery. Fourteen patients with radiographic evidence of bone loss and residual pocketing > 6 mm on bilaterally matched sites were given preliminary scaling polishing and oral hygiene instructions before undergoing contralateral flap surgery. For the measurements a "drufo" soft stent was used. The clinical parameters measured included plaque index (PlI), gingival index (GI), bleeding index (B1), probing pocket depth (PPD), probing attachment level (PAL), furcation involvement, and classification of bony defects. Measurements were recorded at baseline and at 6, 12, and 26 weeks. At experimental sites, a collagen membrane was adapted to the root surfaces, extending 2 mm apical to the bone crest to just subgingival. The control sites underwent a similar procedure but without the placement of a collagen barrier. The experimental sites were selected at random.
Results showed that there was a significant improvement in the PlI, GI, and BI at both test and control sites at 6,12, and 26 weeks compared to baseline but no significant difference between these sites. Probing pocket depth and probing attachment levels showed significant improvement at 12 and 26 weeks postsurgery compared with baseline for both test and control sites. However, the improvement of PPD and PAL were significantly greater in the sites receiving collagen compared with control sites. The actual healing process was evaluated by clinical assessment. These means of evaluation do not disclose whether healing had occurred via repair or by real regeneration of true attachment (i.e., periodontal ligament, cementum, and bone).The authors conclude that this investigation shows that human collagen as a GTR membrane is beneficial in reducing probing pocket depth and producing a gain of probing clinical attachment. [M.O.]
Al-Arrayed, F., S. Adam, J. Moran, and P. Dowell, J Clin Periodont, 22:371, 1995