A comparison of two techniques to augment maxillary sinuses using the lateral window approach: rigid synthetic resorbable barriers versus anorganic bovine bone. Five-month post-loading clinical and histological results of a pilot randomised controlled clinical trial.
OBJECTIVE
To compare the efficacy of two different techniques to augment maxillary sinuses using a lateral window approach: rigid synthetic resorbable barriers (Inion) versus granular anorganic bovine bone (Bio-Oss).


METHODS
Ten partially edentulous patients having bilaterally 1 to 5 mm of residual bone height and at least 5 mm bone width below the maxillary sinuses, as measured on computed tomography (CT) scans, were randomised to receive two different 2-stage sinus lift procedures using the lateral window approach. In one side, the sinus lining was raised by placing a resorbable rigid Inion barrier without any bone substitute whereas the contralateral side was loosely packed with 100% granular Bio-Oss. After 6 months, 2 to 3 implants were inserted at each side and submerged for 4 months. Implants were loaded with provisional acrylic prostheses and replaced after 4 months, by definitive screwretained metal-ceramic prostheses. Outcome measures were: time necessary to complete the augmentation procedure, bone gain on CT scans, histomorphometry, any complication, implant and prosthetic failures, and clinician and patient preference assessed by a blinded outcome assessor. All patients were followed up to 5 months after loading.


RESULTS
No patient dropped out. There was no significant difference in time to complete the augmentation procedure (19.8 minutes for Inion versus 20.5 for Bio-Oss). After 6 months, both interventions gained bone in a highly statistically significant way (14.4 mm for Inion versus 14.1 mm for Bio- Oss) with no significant differences between the procedures. Histologically, more new bone formed at Bio-Oss treated sites (36.1% versus 24.2%), the difference being highly statistically significant (P = 0.002). There were no differences in complications between groups (2 perforations of the maxillary lining at Inion treated sites versus 1 at a Bio-Oss site), however, in one of the patients where a perforation occurred at the Inion site, at implant placement, the sinus was two-thirds filled with soft tissue and the site was successfully retreated with Bio-Oss. No implant failed. The clinician preferred Bio-Oss because it was simpler to handle. There were no statistically significant differences in patient preference 1 month after surgery and 1 month after delivery of definitive prostheses: 8 patients had no preference while 2 preferred the Bio-Oss treated side.


CONCLUSIONS
Although bone grafting is not needed to augment atrophic maxillary sinuses since it is sufficient to keep space with a rigid barrier, bone was histologically more mature and appeared to be clinically harder when using Bio-Oss. Moreover, it was judged simpler to fill sinuses with a bone substitute than to position a rigid barrier for maintaining space.
Felice
Pietro
P
Department of Periodontology and Implantology, University of Bologna, Bologna, Italy.
Scarano
Antonio
A
Pistilli
Roberto
R
Checchi
Luigi
L
Piattelli
Maurizio
M
Pellegrino
Gerardo
G
Esposito
Marco
M
D020341:Absorbable Implants; D000328:Adult; D001861:Bone Regeneration / Q000187:drug effects; D018786:Bone Substitutes / Q000494:pharmacology; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D005260:Female; D016557:Guided Tissue Regeneration, Periodontal / Q000009:adverse effects / Q000379:methods*; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000534:rehabilitation*; D019344:Lactic Acid; D008297:Male; D008443:Maxillary Sinus / Q000601:surgery*; D008567:Membranes, Artificial; D008875:Middle Aged; D008903:Minerals / Q000494:pharmacology; D013516:Oral Surgical Procedures, Preprosthetic / Q000009:adverse effects / Q000379:methods*; D010865:Pilot Projects; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D016896:Treatment Outcome
C077540:Bio-Oss; D018786:Bone Substitutes; D008567:Membranes, Artificial; D008903:Minerals; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid