Guided bone regeneration with barrier membranes ‐ a clinical and radiographic follow‐up study after 24 months

Abstract

The present follow-up study evaluated clinical and radiographic parameters of dental implants placed with simultaneous guided bone regeneration with expanded polytetrafluoroethylene (e-PTFE) membranes. All implants were functioning well 24 months after insertion. In all, 63 patients with a total of 91 e-PTFE-augmented implants were integrated in a regular maintenance protocol. Modified periodontal data of 85 implants in 59 patients were recorded at 24 months and indicated no difference to implants placed in sufficient pristine bone. The mean plaque score (mplI) was 0.29, 74% of the sites showed no plaque. The sulcular probing depth ranged from 1 to 7 mm with a mean of 2.6 mm (SD +/- 0.8). Of the sites 96.5% were < or = 4 mm deep, in 49% of them probing resulted in bleeding. Periotest values 6 and 24 months (mean: -3.4 and -3.4) after placement revealed stable peri-implant conditions and sustained osseointegration. The radiographic evaluation performed 6, 12 and 24 months post insertion yielded a mean bone loss of 0.93, 1.36 and 1.51 mm ranging from 0 to 4 mm. The short-term results of our clinical study demonstrated stable peri-implant conditions 2 years after membrane-protected osseous regeneration. The newly formed bone seemed to be able to withstand functional loading in a predictable manner after 18 months.

A randomized‐controlled clinical trial evaluating clinical and radiological outcomes after 3 and 5 years of dental implants placed in bone regenerated by means of GBR techniques with or without the addition of BMP‐2

“…2001;Hämmerle et al 2002). However, the majority of the studies evaluated the implants over an observation period of less than 5 years and are mainly prospective or retrospective cohort studies (Lorenzoni et al 1999;Christensen et al 2003). In addition, very scarce data are available on studies evaluating the long-term outcome of implants placed in bone regenerated by the use of osteoinductive proteins (Cochran et al 2000).…”

The effects of guided tissue regeneration (GTR) on modified Le Fort I osteotomy healing in rabbits

“…However, it is not clear whether the uncovered defects would have healed better given more time and this point needs to be investigated. It has been suggested that the biological basis of GTR is that tissues found in the wound site during the healing phase will determine the resultant type of tissue that replaces the clot [4][5][6][7]9,[11][12][13][14][15][17][18][19][20][21][22][23][24] . Therefore, allowing fibrous tissue to repopulate the defect site first will impede osteogenesis and result in fibrous tissue dominating the defect area.…”

“…Fibrosis is associated with poor blood supply and the possibility of bacterial implantation and fibrous nonunions can lead to unfavorable results where a rigid structure is needed for function and support. Several studies have shown that in a variety of clinical applications barrier membranes enhanced the bony wound healing compared to sites not covered with a membrane 4,5,9,11,21,24 .…”

“…However, with larger osteotomies and bony defects (e.g., trauma, tumor resection) where a significant gap exists between the bony margins, the risk of developing a fibrous nonunion at the osteotomy site increases, possibly from the rapid migration of fibrous tissue into the defect. By using a barrier, fibrous tissue can be excluded which in turn enhances bone formation, and consequently results in a more stable osteotomy healing site 4,5,9,11,21,24 .…”

“…In a variety of experimental and clinical applications, barrier membranes were utilized to enhance wound healing such as extraction sockets, periapical defects, periodontal defects, implant dehiscences, small osteotomy sites, and prevention of peridural fibrosis after spinal surgery [4][5][6][7]9,[11][12][13][14][15][17][18][19][20][21][22][23][24] . Independent of ongoing discussions and controversies on the utility of barrier membranes the following question was formulated: Can Guided tissue regeneration (GTR) work on a much larger osteotomy defect where there is a functional load present such as in a Le Fort procedure?…”