Chizu Tateishi

Osseous healing after a sagittal splitting ramus osteotomy.

The purpose of this study was to examine osseous healing in the cleavage between the bone fragments after sagittal splitting ramus osteotomy (SSRO) utilizing computed tomography (CT). The subjects were 13 patients with mandibular prognathism who underwent bilateral SSRO. CT was used to study the rami immediately after surgery, then 6 months, 1 year, and 2 years after surgery. Many concave type (the angle between the cleavage >90°) anterior borders developed into the stairway type (the angle between the cleavage <90°) 6-12 months after surgery. Few borders changed to the smooth type. Almost all of the stairway and concave posterior borders changed to the smooth type in the 6-12 months after surgery. Regarding the posterior borders 1 year after surgery, the cleavage of distal and proximal bone fragments demonstrated stable osseous healing (smooth type) in cases where the length and width between the bone fragments were large. In conclusion, the authors successfully demonstrated detailed osseous healing in the cleavage between the bone fragments after SSRO. Remodelling between bone fragments is a major mechanism of osseous healing after this procedure.

Retrospective study of changes in the sensitivity of the oral mucosa: sagittal split ramus osteotomy (SSRO) versus intraoral vertical ramus osteotomy (IVRO).

We investigated changes in the sensitivity of cutaneous points and the oral mucosa after sagittal split ramus osteotomy (SSRO) and assessed the differences between SSRO and intraoral vertical ramus osteotomy (IVRO). The subjects included in this study were 46 patients with mandibular prognathism who underwent IVRO (88 rami) and 30 patients who underwent SSRO (59 rami). An objective evaluation of the neurosensory status of each patient was completed preoperatively and at 1, 4, 8, 12, and 24 weeks postoperatively. Other variables studied for each patient included sex, age, magnitude of mandibular setback, and amount of blood loss during surgery. We found that a neurosensory recovery occurred earlier in the oral mucosa than at cutaneous points. The number of oral mucosa points showing reduced neurosensory function and neurosensory disturbance after SSRO was significantly higher than after IVRO at 1, 4, and 8 weeks (P<0.05). The nerve recovery observed after SSRO was delayed for a longer period than that noted in our previous study of IVRO. In conclusion, we found changes in sensitivity at cutaneous points and the oral mucosa after SSRO and assessed the differences between SSRO and IVRO.

Changes in the sensitivity of cutaneous points and the oral mucosa after intraoral vertical ramus osteotomy

In this study we investigated the changes in the sensitivity of cutaneous points and the oral mucosa that occur after intraoral vertical ramus osteotomy (IVRO). Additionally, postoperative changes in the sensitivity and the relationships between neurosensory disturbance and factors associated with IVRO operations were evaluated. An objective evaluation of the neurosensory status of cutaneous points and the oral mucosa of each patient was completed preoperatively and at 1, 2, 4, 8, 12, and 24 weeks postoperatively. The other variables studied for each patient included sex, age, magnitude of mandibular setback, and the amount of haemorrhage that occurred during surgery. In addition, the relationships between neurosensory disturbance and factors connected with IVRO operations were evaluated. We found that at cutaneous points, contributing factors such as sex, age, the magnitude of mandibular setback, and haemorrhage were associated with an increased risk of neurosensory disturbance after IVRO. However, these factors were not associated with that in the oral mucosa. In conclusion, we demonstrated the changes that occur in the sensitivity of cutaneous points and the oral mucosa after IVRO, the postoperative changes in sensitivity, and the relationships between neurosensory disturbance and factors connected with IVRO operations.

Devices for facial aesthetic improvement in the treatment of skeletal mandibular protrusion.

Some techniques for the treatment of mandibular protrusion with consideration for aesthetic improvement of the face as a whole are described. The aesthetic inferiority complex in the mind of patients with masticatory disorders as the chief complaint should not be underestimated. Three techniques were used in this study; preoperative orthodontic treatment, preservation of the patients self-image, and maintenance of beautiful relationship between the midfacial line and the nasolabial fold as well as the nasal ala.

Aesthetic Changes in Lateral Lip Profile After Sagittal Split Ramus Osteotomy — Implications for Informed Consent

Abstract Objectives: This study aimed to evaluate the changes in the lip region after correction of skeletal mandibular protrusion, select the minimum necessary aesthetic items to explain to patients, and summarise the pertinent points when explaining surgery. Patients and Methods: Eight reference points in the aesthetic facial lateral view were established and the mean values and standard deviation of the changes in 19 measurement items comprising the reference points before and after surgery were calculated and compared with normal values. A multivariate analysis of principal components was carried out for items showing significant changes after surgery to elucidate the characteristics of the aesthetic changes. Results: The results suggest that the items essential for preoperative explanation of significant postoperative changes are correction of the fat lower lip profile, improvement of the antero posterior relationship between the upper and lower lips, and flattening of the upper lip, which presents no aesthetic problems. Conclusion: This study highlights the necessity and extent of the explanation regarding aesthetic changes in the area of the lips after orthognathic surgery.