Lateral alveolar ridge augmentation using a synthetic nano-crystalline hydroxyapatite bone substitution material (Ostim): preliminary clinical and histological results.
OBJECTIVE
The purpose of this preliminary two-center clinical prospective study was to evaluate the tissue composition of augmented sites after the use of a nano-crystalline hydroxyapatite (ncHA) bone substitution material by clinical and histological examinations.


METHODS
A synthetic ncHA augmentation material was used without any additives in 14 patients requiring lateral ridge augmentation 6-7 months before (10 patients) or at implant placement (four patients). The ncHA material was covered by a titanium mesh for space maintenance. Clinical and radiographic parameters were evaluated and bone biopsy cores, obtained 6-7 months following augmentation, were assessed histologically and histomorphometrically.


RESULTS
One patient showed gingival swelling, redness and pain at the augmentation site requiring removal of the titanium mesh 6 weeks postoperatively. In seven patients, a premature exposure of the titanium mesh without any inflammatory symptoms was noted. The width of the fixed gingival and the alveolar ridge height did not change significantly at least 6 months following augmentation (P>0.5), whereas a significant gain in alveolar ridge width (P=0.01) was noted. After a median period of prosthetic loading of 24 months, no implant was considered to be a failure. Histology revealed ncHA remnants in peripheral and central parts of biopsy cores obtained from seven patients after at least 6 months without histological symptoms of inflammation, whereas histomorphometry of bone cores revealed no significant differences of the mean percentage area of ncHA in peripheral (23.4%) and central (15.1%) parts of biopsy cores (P=0.262). The mean percentage area of bone colonizing the defect was 52.3%.


CONCLUSIONS
Small amounts of ncHA were found after at least 6 months in bone biopsies. The former defect space was filled with bone. The alveolar ridge width gain was found to be significant after lateral augmentation utilizing ncHA, providing a quantitatively and qualitatively sufficient site for primary stable implant placement.
Strietzel
Frank Peter
FP
Department for Oral Surgery and Dental Radiology, Campus Virchow Clinic Charité Centre 3 for Dental Medicine, Charité- Medical University Berlin, Berlin, Germany. frank.strietzel@charite.de
Reichart
Peter A
PA
Graf
Hans-Ludwig
HL
D000293:Adolescent; D000368:Aged; D000539:Alveolar Process / Q000187:drug effects* / Q000378:metabolism / Q000601:surgery; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D018786:Bone Substitutes / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use*; D003758:Dental Implantation, Endosseous / Q000379:methods*; D017886:Durapatite / Q000737:chemistry / Q000378:metabolism / Q000627:therapeutic use*; D005260:Female; D048091:Guided Tissue Regeneration / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D053758:Nanoparticles / Q000737:chemistry / Q000627:therapeutic use; D016348:Osseointegration / Q000187:drug effects; D011446:Prospective Studies; D016896:Treatment Outcome
D018786:Bone Substitutes; D017886:Durapatite