Comparative histomorphometric analysis of maxillary sinus augmentation with absorbable collagen membrane and osteoinductive replaceable bony window in rabbits.

PURPOSE: The aim of this animal study was to evaluate, through histomorphometric evaluation, bone regeneration in rabbit maxillary sinuses with absorbable collagen membranes and osteoinductive replaceable bony windows over bone grafts. MATERIALS AND METHODS: Bilateral sinus augmentation procedures were performed in 16 adult male rabbits. The rabbits were randomly assigned to 4 groups of 4 rabbits each. Rectangular replaceable bony windows were made with a piezoelectric thin saw insert. In control group, grafted ß-tricalcium phosphate (ß-TCP) was covered by absorbable collagen membranes. In experimental groups, ß-TCP was grafted and covered by replaceable bony windows. The rabbits were killed at 1, 2, 4, and 8 weeks postoperatively. The augmented sinuses were stained with hematoxylin-eosin and Masson trichrome stains and examined, under light microscopy, for newly formed bone and soft tissue changes in the maxillary sinuses. RESULTS: Histologically, significantly higher and faster new bone formation was observed in the augmented sinuses of the experimental groups, receiving homologous replaceable bony windows than in those of the control group receiving collagen membranes. CONCLUSION: This study demonstrates that, for augmentation, the use of the homologous replaceable bony window over bone graft material on the maxillary sinus accelerates bone regeneration.

Histomorphometric evaluation of mineralized cancellous allograft in the maxillary sinus augmentation: a 4 case report.

PURPOSE: The aim of this article is to report the histomorphometric analysis and clinical study of mineralized cancellous bone allografts in maxillary sinus augmentation procedures in 4 cases. MATERIALS AND METHODS: Sinus bone augmentation, using a piezoelectric device and mineralized cancellous allografts, was performed in 3 patients. After an average of about 8 months of healing, a trephine core sample was gained from the lateral windows area for histomorphometric analysis. The mineralized cancellous allografts demonstrated normal healing of hard tissues. RESULTS: Upon reentry for dental implant placement or secondary surgery, the graft materials showed hard bony structures within the maxillary sinus. Histomorphometric analysis of the cores revealed an average vital new bone content of 17.88%. CONCLUSION: Mineralized cancellous allografts showed favorable bone regeneration histologically and was clinically useful in augmenting bone volume for implant placement in the sinus bone graft.

Fungal infection as a complication of sinus bone grafting and implants: a case report.

Sinus bone grafts have been used successfully to augment atrophic posterior maxilla for dental implant placement. Even though sinus bone grafting is generally considered to be a safe surgical procedure, postoperative maxillary sinus infections can occur and therefore need to be considered. Bacteria, as well as viruses and fungi, have been identified as causative agents. Because fungal infection of the maxillary sinus after sinus bone grafting is not well known, we report a case of a middle-aged male patient along with the clinical, radiographic, and histologic findings. The patient was referred from his private dentist because of failed sinus bone grafting and osseointegration of implants. The surgical approach to the sinus yielded a friable mass of brownish-red material from the sinus. Review of pathology slides revealed a noninvasive hyphal mass caused by Aspergillus and polypous mucosa. After surgical removal of the mycotic masses, sinus bone grafting, using allograft, was performed. Bone formation after the healing period was favorable and dental implants were placed. There was no recurrence of fungal sinusitis.

Minor tooth movements using microimplant anchorage: case reports.

For the treatment of extruded or tipped molars, various conventional techniques have been used. But those methods may lead to undesirable movement of the anchorage units and lengthen treatment time because of limited tooth-borne anchorage potential. Introduction of microimplants as orthodontic anchorage has expanded treatment possibilities because of their advantages. Some advantages are a less complex surgical procedure, decrease in cost, immediate loading, and their ability to be placed in any area of the alveolar bone. This article will illustrate clinical experiences in patients who were treated with the intrusion of overerupted molars, the up-righting of tilted molars, and other clinical applications for minor tooth movements. Anchorage control was achieved with the surgical insertion of titanium microimplants for immediate loading in the alveolar bone. When needed, minimal fixed appliances were used and orthodontic treatment was completed without any other complications.