Early loading of implants in vertically augmented bone with non-resorbable membranes and deproteinised anorganic bovine bone. An uncontrolled prospective cohort study.
BACKGROUND
All materials used in this study were purchased by the author and it is therefore free of any commercial or institutional interest.


OBJECTIVE
To evaluate the success rate 1 year after loading of early loaded implants placed in vertically augmented bone using deproteinised bovine bone (Bio-Oss) and a titanium-reinforced membrane (Gore-Tex).


METHODS
Twenty patients provided 25 sites that were treated with vertical guided tissue regeneration (GBR) using Bio-Oss and expanded polytetrafluoroethylene titanium-reinforced membranes. After 1 year of healing, the membranes were removed and 64 implants were placed (baseline) and loaded 30 days later. Standardised periapical radiographs were obtained at baseline and 1 year thereafter. One independent assessor clinically evaluated the amount of tissue regenerated and peri-implant bone level based on the radiographs. Outcome measures were prosthesis success, implant success, complications, amount of vertically regenerated bone, peri-implant marginal bone levels and histology.


RESULTS
No patient dropped out. A total of 23 out of 25 sites healed uneventfully. Two sites showed early membrane exposure. In these sites, the surgery was repeated with success 2 months later. Clinical evaluation showed a mean vertical bone defect of 5.6 mm (SD 1.7). Mean vertical bone gain after GBR was 5.2 mm (SD 1.5). The histology of five samples retrieved from four patients showed a total percentage of xenograft and new bone of 52.6%, with dispersed graft particles surrounded by layers of bone. All implants were stable after 1 year of function, yielding a survival rate of 100%. Statistically significant peri-implant bone loss (0.95 mm; SD 0.21; 95% confidence interval 0.85 to 1.05; P < 0.001) was observed radiographically from baseline to the 1-year follow-up.


CONCLUSIONS
This prospective cohort study shows that by using deproteinised bovine bone and a non-resorbable titanium-reinforced membrane, vertical bone gain can be obtained and implants can be loaded after 30 days. The vertical regenerated tissue exhibited good stability over 1 year of implant function.
Todisco
Marzio
M
Brescia, Italy. todiscomarzio@libero.it
D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000209:etiology; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D001861:Bone Regeneration; D018786:Bone Substitutes; D015331:Cohort Studies; D003758:Dental Implantation, Endosseous; D015921:Dental Implants / Q000009:adverse effects; D019094:Dental Prosthesis, Implant-Supported; D005260:Female; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D006801:Humans; D008297:Male; D008567:Membranes, Artificial; D008875:Middle Aged; D008903:Minerals; D011138:Polytetrafluoroethylene; D011446:Prospective Studies; D011859:Radiography; D013997:Time Factors; D014025:Titanium; D016896:Treatment Outcome; D014716:Vertical Dimension
C077540:Bio-Oss; D018786:Bone Substitutes; D015921:Dental Implants; D008567:Membranes, Artificial; D008903:Minerals; D011138:Polytetrafluoroethylene; D014025:Titanium