Abstract:

BACKGROUND: Alveolar bone augmentation using a unidirectional distraction device may lead to axial displacement. A bidirectional distraction device can control the vertical and buccal-lingual directions. But studies regarding this have been rarely reported.
OBJECTIVE: To develop a bidirectional alveolar bone distraction device and to investigate its effects on osteogenic effects through an animal experiment.
METHODS: Four adult mongrel dogs were established into models of alveolar bone atrophy by extraction of unilateral mandible premolars. After 1 month, alveolar bone was cut open and a bilateral distraction device was placed. Seven days later, the distraction was started at a rate of 1 mm/day for 5 days. At last, buccal-lingual direction distraction (approximately 2.4 mm) was taken for once, followed by a consolidation period of 2 months. Subsequently, gross observation and histological examination of samples were performed.
RESULTS AND CONCLUSION: Among the four dogs, mucous membrane wound was well healed in two dogs, and wound dehiscence was observed in two dogs but healed after secondary debridement and suture. No loosening of distraction devices was observed. The segments were augmented (5.0±0.2) mm in alveolar direction and (2.4±0.3) mm in buccal direction. There were newly formed bones as shown by gross observation and histological examination. Results suggest that a bidirectional distraction device can well control the transport bone in alveolar and buccal-lingual directions and promote new bone formation.