Postoperative exposure of bioresorbable GTR membranes: effect on healing results

Abstract

The goal of this investigation was to evaluate the effect of postoperative exposure of two different bioresorbable membranes on the guided tissue regeneration (GTR) healing results compared to nonexposed sites. In each of 25 patients one pair of contralateral intrabony lesions was treated either with polylactic acid (PLA) or polyglactin 910 (PG-910) membranes. Postoperative exposure occurred in 9 PLA and 13 PG-910 sites. Standardized clinical [papillary bleeding index (PBI), gingival recession (REC), probing pocket depth (PPD), probing attachment level (PAL)] and radiographic examinations (digital subtraction radiography) were performed immediately before (baseline) and 6 and 12 months postoperatively (p.o.). Subgingival bacterial samples from surgical sites were evaluated by culture at baseline, 6 weeks, and 6 and 12 months p.o. Six months after surgery the changes (delta) of REC were significantly (P < or = 0.05) greater in exposed than in nonexposed sites, independently of the membrane material (median): exposed sites, delta REC = -1 mm; nonexposed sites, delta REC = 0.0 mm. However, 12 months p.o. no significant differences were found due to a decrease in the initial recessions in exposed sites. Although a higher percentage of exposed than nonexposed sites harbored periodontal pathogens 6 weeks p.o. at the gingiva-faced membrane surface, membrane exposure did not have a significant negative effect on delta PPD, delta PAL, or radiographic bone density changes 6 and 12 months p.o. Both membranes showed significant gains in PAL and bone density in both exposed and nonexposed sites. In conclusion, this study demonstrates that with consistent infection control the postoperative exposure of PLA and PG-910 membranes has no significant negative effect on the regeneration outcome, although higher initial gingival recessions must be expected than in the nonexposed sites. However, in exposed sites plaque and infection control were clearly impeded by the rough, exposed membrane surfaces and by the initially negative gingival morphology.

Allograft and Alloplastic Bone Substitutes: A Review of Science and Technology For the Craniomaxillofacial Surgeon

“…79,80 They can also be used as absorbable membranes in guided bone regeneration (GBR) in which a bone graft material is placed in the defect and covered with the membrane to provide a barrier that excludes unwanted tissues and cells, creates and maintains space, protects the underlying blood clot, and stabilizes the wound. 81 Absorbable GBR membranes have been used extensively in oral surgery 82 and may have application in long bone procedures. 83 Composites of bioabsorbable polymers and ceramics have been investigated as bone graft substitute materials.…”

Guided tissue regeneration in intrabony defects using an experimental bioresorbable polydioxanon (PDS) membrane

“…wound healing potential, immune system, oral hygiene, defect morphology, smoking habits) (Tonetti et al 1995, Kornman & Robertson 2000, Cortellini & Tonetti 2000, there is strong evidence that membrane specific problems (e.g. Although the strict plaque control regimens of previous controlled clinical studies appeared to prevent a harmful effect of postoperative membrane exposures on the attachment gain (Becker et al 1996, Christgau et al 1997b, membrane exposures dramatically increase the risk for bacterial contamination and penetration of the exposed membrane parts (Grevstad & Leknes 1993, Nowzari et al 1995, Nowzari et al 1996, Chen et al 1997, MacDonald et al 1998). Bacterial contamination of the membranes can have a detrimental effect on the periodontal regeneration (Nowzari et al 1995, Slots et al 1999.…”

Study of Thermolysis of Hydrogenated Carbon Molecules as Products of Fullerenization of Benzene, Xylene, Ethanol and Pyridine

“…In order to overcome these issues, a variety of bioabsorbable materials, such as polylactid and polyglycolic acids or collagen have been used as membrane barriers [9]. Barrier materials derived from type I and III porcine or bovine collagen demonstrated their usefulness in GTR procedures [10][11][12]. However, several complications such as early membrane degradation, epithelial downgrowth and premature loss of the material were reported following the use of collagen materials [1].…”