Abstract
One of the most important aims of secondary bone grafting is to allow for the closure of the cleft defect and provide a more ideal dental arch form orthodontically without any prothesis.
This study evaluated the bone bridge formation in 24 patients with a total of 29 clefts three dimentionally using X ray computed tomography and investigated its relationship with the subsesuent orthodontical repositioning of teeth adjacent to the cleft into the grafted sites.
Results are as follows: 1) Satisfactory bone formation was found only in 6 patients (20%).2) 20 clefts (69%) showed insufficient bone formation, which might disturb the movement of the teeth or either side of the cleft. In many of these cases, the lack of bone formation was observed of the nasal and medial sides of the cleft.3) Continuous but very thin bone bridge was recognized in 3 clefts (10%), which made the orthodontic closure of the arch impossible.
In conclusion, this study demonstrate d two major points concerning the surgical procedure: 1) It is important to raise the cleft mucoperiosteal flap superiorly enough along the cleft wall and trim the surplus tissue to make the nasal floor flat, deep and wide.2) It is also important to fill the alveolar cleft completely with small chips of cancellous bone and marrow only.