Mandible Distraction Using Internal Device

Dermal-Fat Graft for Facial Contouring in Patients With Craniofacial Microsomia

Craniofacial microsomia (CFM) is a variable craniofacial malformation, related to the development of the structures originated from the first and second brachial arches, affecting skeletal tissue, soft tissue, and neuromuscular components. In the situation of subcutaneous tissue and chewing muscles hypoplasia, free tissue transfer is a treatment option. Dermal-fat graft allows easy modeling during surgery, volumetric gain and improvement of asymmetry. The aim of this study was to evaluate the facial contour and the percentage of symmetry after the use of dermal-fat graft in patients with CFM, who had already submitted to osteotomies, attended at the Associate Center for Cleft Lip and Palate (CAIF) during 2001 to 2018. For analysis, the authors selected 17 patients who fulfilled the above prerequisites. The symmetry study was done by the analysis of preoperative and postoperative photographs in the Image J software. Two standard points were used: nasal base and upper lip limit. On the nasal base, the preoperative analysis showed a hypoplastic side with a median of 93.00% of the normal side size, rising to 97.78% in the postoperative period. On the upper lip limit, the preoperative analysis showed a median of 87.80% and, in the postoperative period, 98.15%. Analysis of the interaction between the operative moments and the modified Pruzansky classification showed that there were no significant differences between grades. Long-term evaluation demonstrated that the use of a dermal-fat graft for correction of facial symmetry was effective and close to 100%, regardless of the degree of hypoplasia of the patient.

One-Year Relapse of Mandibular Distraction for Hemifacial Microsomia Using Masseteric Botulinum Toxin Type A Injections

BACKGROUND

The relapse of hemifacial microsomia was thought to be highly related to the soft tissue envelope around the mandible angle mainly composed by masseter and medial pterygoid. According to the reason, we tried to apply masseter injection of type A botulinum toxin to weaken the soft envelope tension on the early stage post mandible distraction in adult HFM patients.

METHODS

Eight patients diagnosed with HFM were studied and randomly assigned to an experimental or control group. Patients in the experimental group were treated with DO, orthognathic surgeries, autologous fat grafting, and bilateral masseter muscle injection with type A botulinum toxin. The patients in control group were treated with the same procedures as the patients in experimental group except for masseter muscle injection with type A botulinum toxin. The recurrence rates of both groups were evaluated and analyzed after nearly 1 year of follow-up.

RESULTS

The mean recurrence rate was 26.30% ± 11.84% (range 7.62%-37.27%) in the 8 patients after 1-year follow-up. The relapse rate was 16.32% ± 7.78% (7.62%-26.22%) in the experimental group and 36.28% ± 1.03% (34.84%-37.27%) in the control group. There was a significant difference (P = 0.002) between the experimental group and the control group.

CONCLUSIONS

The combination of DO, orthognathic surgeries, autologous fat particle transplantation, and masseter muscle type A botulinum toxin injection technique could be a comprehensive treatment plan for adult patients of HFM. Furthermore, masseter injection of type A botulinum toxin might be an alternative method to reduce the early recurrence rate of postoperative adult patients of HFM.

Bimaxillary Orthognathic Approach to Correct Skeletal Facial Asymmetry of Hemifacial Microsomia in Adults

BACKGROUND

Hemifacial microsomia (HFM) is the second most common congenital craniofacial deformity after cleft lip and palate. Distraction osteogenesis (DO) is regarded as an alternative and efficient treatment option for patients with HFM. However, DO was not proven effective for all cases, and the results of long-term follow-up were not satisfactory as expected. Compared with DO, the orthognathic surgery approach may offer more stable clinical outcomes for this kind of disease. The purpose of this study is to evaluate the long-term clinical and radiographic outcome of bimaxillary orthognathic surgery in the treatment of adult HFM.

METHODS

Eight patients with HFM who had undergone bimaxillary orthognathic surgery between 2008 and 2012 were included in the study. The surgical procedures included Le Fort I osteotomy, inverted-L osteotomy, sagittal split ramus osteotomy, genioplasty, and iliac bone grafting. Pre- and postoperative orthodontic treatments were performed, respectively. Clinical and radiographic examinations were carried out to assess postoperative outcomes.

RESULTS

No obvious complications appeared postoperatively and no recurrences occurred during follow-up. All patients obtained satisfactory aesthetic results. Marked improvement in facial contour and occlusion were observed. Plain radiographs showed that the height ratios between the affected and unaffected ramus were ameliorated significantly.

CONCLUSION

The bimaxillary orthognathic approach to correct the deformity of adult HFM can obtain stable results in the long-term follow-up, and should be considered as a priority method for the treatment of adult patients with dentofacial deformity.

LEVEL OF EVIDENCE V

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Biomechanical configurations of mandibular transport distraction osteogenesis devices

Mandibular bone transport (MBT) distraction osteogenesis devices are used for achieving reconstruction of mandibular defects in a predictable way, with few complications, less complexity than other alternative surgical procedures, and minimal tissue morbidity. However, selection of appropriate MBT device characteristics is critical for ensuring both their mechanical soundness and their optimal distraction function for each patient's condition. This article assesses six characteristics of currently available MBT devices to characterize their design and function and to classify them in a way that assists the selection of the best device option for each clinical case. In addition, the present work provides a framework for both the biomechanical conception of new devices and the modification of existing ones.