Guided bone regeneration around endosseous implants with anorganic bovine bone mineral. A randomized controlled trial comparing bioabsorbable versus non-resorbable barriers.
BACKGROUND
Guided bone regeneration (GBR) is a viable treatment for osseous defects surrounding dental implants. Controversy exists regarding the choice of barrier membrane used and the method of membrane fixation to achieve GBR.


METHODS
This study compared the efficacy of a porcine-derived bioabsorbable collagen membrane and an expanded polytetrafluoroethylene (ePTFE) membrane (non-resorbable) for GBR using a bovine bone xenograft/autograft bone composite in defects surrounding dental implants. The study also examined the effect of primary barrier fixation on GBR. Defect size was recorded at Stage 1 and 2 surgeries (performed 6 months apart). Forty-eight subjects (41% males, 59% females) requiring GBR were treated with either collagen (23) or ePTFE (25) barriers, respectively. Implants were titanium self-tapping screw-type. In 34 GBR sites, barrier fixation was achieved with polylactic acid resorbable pins. The remaining barriers were secured with the implant cover screw and/or embedded beneath the flaps.


RESULTS
At 6 months, a decrease in defect width (collagen barrier 1.95 +/- 0.60 mm, ePTFE barrier 2.65 +/- 0.56 mm), length (collagen barrier 2.65 +/- 0.61 mm, ePTFE barrier 2.26 +/- 0.66 mm), and circumference (degrees) (collagen barrier 57.7 +/- 18.7, ePTFE barrier 80.2 +/- 19.9) was observed for both membranes. A significant number (chi2, P = 0.041) of postoperative complications occurred when barrier fixation was lacking at initial surgery. Furthermore, a significant difference (P <0.05) in the success of GBR with respect to defect size was observed when barrier fixation was taken into account.


CONCLUSIONS
In conclusion, both collagen and ePTFE barriers proved suitable for achieving GBR of osseous defects surrounding dental implants. The results of this study stress the importance of barrier fixation at the time of initial surgery.
Carpio
L
L
Department of Periodontology, Harvard School of Dental Medicine, Boston, MA 02115, USA. Lillian_Carpio@hms.harvard.edu
Loza
J
J
Lynch
S
S
Genco
R
R
D020341:Absorbable Implants; D000328:Adult; D016301:Alveolar Bone Loss / Q000209:etiology* / Q000601:surgery*; D000818:Animals; D001861:Bone Regeneration; D018786:Bone Substitutes; D002417:Cattle; D016009:Chi-Square Distribution; D003094:Collagen; D003758:Dental Implantation, Endosseous / Q000009:adverse effects; D015921:Dental Implants / Q000009:adverse effects*; D019232:Dental Restoration Failure; D005260:Female; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D006801:Humans; D008297:Male; D008567:Membranes, Artificial; D008903:Minerals; D011138:Polytetrafluoroethylene; D013552:Swine; D016896:Treatment Outcome
C077540:Bio-Oss; D018786:Bone Substitutes; D015921:Dental Implants; D008567:Membranes, Artificial; D008903:Minerals; D011138:Polytetrafluoroethylene; D003094:Collagen