Comparative Study Between Lyophilized or Frozen Bone Allografts for Sinus-lifting
Comparative Study Between Lyophilized or Frozen Bone Allografts for Sinus-lifting
Bone resorption and atrophy in maxillary posterior region is due to severe periodontal
 disease and is consequent tooth extractions. Sinus pneumatisation can occur after tooth
 extraction and alveolar bone loss. Consequently, bone-reducing volume at that region is a
 great challenge to implantodontists. Sinus lifting surgery have been practiced since 80's and
 many biomaterials have been used to solve filling issues to maintain the sinus floor lifted
 in a position that can allow dental implants installation. Bone grafts have shown to be the
 best choice of filling grafts. Despite autologous bone are the gold standard filling
 biomaterial it is associates with great mortality and morbidity. So, bone allografts from
 tissue bank had been shown to be an advantageous alternative. Lyophilized or freeze tissue
 bone are the most common allografts but literature is poor in randomized controlled parallel
 clinical trials regarding those filling grafts for sinus lifting. The aim of this study is to
 perform a randomized controlled clinical trial comparing two bone allografts: lyophilized and
 freeze bone allografts from human bone tissue bank. The investigators want to verify which
 one can develop greater osteogenesis, if is there any difference between them regarding the
 architectural trabeculae formation, if there are different patterns of reabsorption and
 finally if is there any differences between them regarding primary and lately dental implants
 stability. To answer those questions the investigators propose firstly, to carry out
 microtomographic and histological analysis from trephine bone samples after six months of
 sinus lifting and grafting in healthy participants undergoing osseointegrated dental
 implants. Secondly, the primary and lately implant stability is going to be achieved
 employing Resonance Frequency Analysis (RFA).
Inclusion Criteria:

 -  healthy

 -  totally or partially edentulous patients, bilaterally, in upper premolar or molar
 region; presenting maxillary sinus lifting necessity with bilateral alveolar bone
 height lower than 5mm and indication for at least one osseointegrated dental implant
 in premolar or molar region.

 Exclusion Criteria:

 -  recent sinusitis history

 -  hypersensibility for sinus allergens, tabagism, ethylism

 -  severe periodontal disease, diabetes, hypertension.

 -  Cases that occur schneiderian membrane perforation will be excluded from the final
 sample.