A pilot study of Cerasorb and Bio-Oss enhanced new bone formation in animal model

The aim of this pilot investigation was to develop a new animal model for studying the effects on osteogenesis of agents used in the guided bone regeneration technique. As test material, a mixture of two osseoconductive materials with different physico-chemical characteristics was used. One component of the mixture was Bio-Oss, a bovine hydroxyapatite; the other was Cerasorb, a synthetic tricalcium phosphate. The mixture consisited of 50 volume percent of Bio-Oss and 50 volume percent of Cerasorb. In in vivo pilot experiment, bone wounds were prepared in the proximal third of both femurs of rabbits. A Cerasorb + Bio-Oss mixture was inserted on the test side and the same amount of sterile buffered physiological solution on the control side. After healing for 4 weeks, the bone segments were embedded and cut without decalcification, using the Exact cutting and grinding system. The density of the newly-formed bone was evaluated histomorphometrically. On the Cerasorb + Bio-Oss test side the bone density was almost 1.5 times higher than that on the control side. These results demonstrated that the applied animal model is appropriate for investigation of the effects on osteogenesis of biocompatible graft materials such as Bio-Oss and Cerasorb.

[Mixed odontogenic tumors in children and adolescents]

Mixed odontogenic tumors in the jaws of children and adolescents usually cause dentition anomalies. The typical forms of these are ameloblastic fibroma, ameloblastic fibroodontoma, complex odontoma and compound odontoma. In the present study mixed odontogenic tumor cases are presented in patients under 20 years of age. All of them were associated with tooth eruption disturbances. Further aim of this study was to discuss the nature and interrelationships of this group of lesions. Ameloblastic fibromas (AFs) are true, mixed, soft tissue neoplasms, deriving from the proliferation of both odontogenic epithelium and mesenchyma. They have a potential to both recurrence and malignant transformation. Ameloblastic fibroodontomas (AFOs) may be regarded as hamartomas, which exhibit epithelial, mesenchymal and abundant hard tissue components of the developing teeth. Odontomas are calcifying benign hamartomas, and represent the most common type of odontogenic jaw tumors among patients less than 20y, having complex and compound variants. Complex odontomas (CXOs) are built up from amorphous hard tissue elements, and generally occur in the premolar or molar regions of the maxilla. Compound odontomas (CDOs) usually appear in the maxilla, in the region of the incisors and canines, and contain small, radio-opaque structures reminiscent of rudimentary teeth. Early diagnosis and treatment of mixed odontogenic jaw tumors in children may prevent the serious orthodontic complications and jaw deformations.

Maxillary sinus floor grafting with β-tricalcium phosphate in humans: density and microarchitecture of the newly formed bone

OBJECTIVES

Graft insertion can effectively enhance the regeneration of debilitated bone. The effects of an alloplastic bone-replacing material, beta-tricalcium phosphate (Cerasorb), and of autogenous bone graft were compared.

MATERIALS AND METHODS

In 17 edentulous patients, the maxillary sinus floor was extremely atrophied to such an extent that implant placement was impossible. The Schneiderian membrane was surgically elevated bilaterally by insertion of Cerasorb (experimental side) and autogenous bone graft (control side). After surgery, the recovery was followed clinically and radiologically. After 6 months, 68 bone cylinders were excised from the grafted areas and implants were inserted into their places. The bone samples were embedded into resin, and the osteointegration of the grafts was studied histologically. Trabecular bone volume (TBV) and trabecular bone pattern factor (TBPf) were quantified by histomorphometry.

RESULTS

Cerasorb proved to be an effective bone-replacing material with osteoconductivity; it was capable of gradual disintegration, thereby providing space for the regenerating bone. The new bone density was not significantly different on the experimental and control sides (32.4+/-10.9% and 34.7+/-11.9%, respectively). However, the graft biodegradation was significantly slower on the experimental side than the control side. The TBPf value was lower on the control side than on the experimental side (-0.53+/-1.7 and -0.11+/-1.4 mm(-1), respectively), but this difference was not significant.

CONCLUSIONS

Six months after insertion of the grafts, the bone of the augmented sinus floor was strong and suitable for anchorage of dental implants, irrespective of whether autogenous bone or Cerasorb particles had been applied.