BACKGROUND: Osteochondroma is a benign tumor that tends to develop in mandibular condyle and coronoid process in the craniofacial region. If tumor mass has grown from condyle into the infratemporal space with zygomatic arch obstructing the access, there are risks associated with surgical exposure and local resection of these masses. CASE PRESENTATION: This study reports on a case of osteochondroma on mandibular condylar head where we treated with surgical excision via preauricular approach with 3D analysis. After the local resection, there were no surgical and post-operative complications until 8-month follow-up period. CONCLUSIONS: In local excision of osteochondroma, our method is a minimally invasive method. It is a good example of osteochondroma treatment.
Follow-Up Studies ; Head ; Mandibular Condyle* ; Methods ; Osteochondroma* ; Osteotomy* ; Zygoma*

OBJECTIVES: Postoperative paresthesia is a common complication after sagittal split osteotomy (SSO). This study aimed to compare paresthesia among different fixation methods one year postoperative. MATERIALS AND METHODS: This prospective cohort study assessed subjects in four groups: class II with miniplate fixation (Group 1), class II with three-screw fixation (Group 2), class III with miniplate fixation (Group 3), and class III with three-screw fixation (Group 4). Paresthesia was evaluated one year postoperative based on a 0-10 visual analogue scale. Pearson correlation was used to evaluate associations of age and mandibular movement with paresthesia. ANOVA was used to compare paresthesia among groups. RESULTS: A total of 80 subjects were enrolled, with 20 subjects in each of the four groups. The Pearson correlation test demonstrated a significant correlation between mandibular movement and paresthesia (P=0.001). Comparison of paresthesia among the groups showed significant differences among groups 1 and 2, 2 and 3, and 3 and 4 (P<0.05). CONCLUSION: The three-screw fixation method led to more paresthesia one year postoperative compared with miniplate fixation. In addition, the magnitude of mandibular movement had a positive correlation with paresthesia.
Cohort Studies ; Follow-Up Studies ; Mandible ; Mandibular Nerve ; Methods ; Osteotomy ; Paresthesia ; Prospective Studies

OBJECTIVETo investigate the condensability of mandibular length.

METHODSIn six goats were used in the study. Corticotomy at right mandibular angles was performed via extral-oral accession. Special devices were applied to shorten the mandible by 0.5 mm per three days respectively.

RESULTS1. Mandibular angles of the six goats were shorten by 0.8 cm to 1.3 cm respectively in 48 days to 78 days; 2. In spite of the lower ascending ramus moving forward and angles being blunt, the occlusion scarcely varied because of contralateral bite-lock; 3. X-ray demonstrated that, at first, bone density in contracted areas declined, and then increased gradually to almost normal density; 4. Under microscope there were three tissues layers from central to lateral within the bone gap: fiber layer, cartilage layer and bone layer, and fiber layer gradually transform into cartilage layer with the fixed time. At the end of fixation they all transform into bone tissue.

CONCLUSIONContraction osteogenesis is actually a process of compression, absorption and rebuilding. It is feasible that using contraction osteogenesis to shorten the mandible via cortcotomy.

Animals ; External Fixators ; Female ; Goats ; Male ; Mandible ; surgery ; Mandibular Advancement ; methods ; Oral Surgical Procedures ; methods ; Osteotomy ; Periosteum ; surgery ; Pressure

BACKGROUND: We evaluated change in the mandibular condyle after orthognathic surgery using cone-beam computed tomography (CBCT) in patients with facial asymmetry. METHODS: Thirty patients with skeletal class III malocclusion and mandibular prognathism or facial asymmetry were classified into two groups according to the amount of menton deviation (MD) from the facial midline on anteroposterior (AP) cephalogram: group A (asymmetry, MD ≥ 4 mm; n = 15) and group B (symmetry, MD < 4 mm; n = 15). Position and angle of condylar heads on the axial, sagittal, and coronal views were measured within 1 month preoperatively (T0) and postoperatively (T1) and 6 months (T2) postoperatively. RESULTS: On axial view, both groups showed inward rotation of condylar heads at T1, but at T2, the change was gradually removed and the condylar head returned to its original position. At T1, both groups showed no AP condylar head changes on sagittal view, although downward movement of the condylar heads occurred. Then, at T2, the condylar heads tended to return to their original position. The change in distance between the two condylar heads showed that they had moved outward in both groups, causing an increase in the width between the two heads postoperatively. Analysis of all three-dimensional changes of the condylar head positions demonstrated statistically significant changes in the three different CBCT views in group B and no statistically significant changes in group A. CONCLUSIONS: There was no significant difference between the two groups in condylar head position. Because sagittal split ramus osteotomy can be performed without significant change in symmetrical and asymmetrical cases, it can be regarded as an effective method to stabilize the condylar head position in patients with skeletal class III malocclusion and mandibular prognathism or facial asymmetry.
Cone-Beam Computed Tomography ; Facial Asymmetry ; Head ; Humans ; Malocclusion ; Mandibular Condyle ; Methods ; Orthognathic Surgery ; Osteotomy, Sagittal Split Ramus ; Prognathism

Among various surgical methods introduced to optimize esthetic results, robotic surgery has gradually expanded in scope. As incision, approach, and operation view in robotic surgery differ from existing surgical methods, we should consider reconstruction from a different perspective. We recently experienced two mandibular reconstruction cases after tumor ablative surgery with robotic neck dissection using the conventional reconstruction method and virtual surgical planning (VSP), respectively. We found that the conventional reconstruction method is inappropriate in modified facelift incision in robotic neck dissection because it provides limited surgical scope, restricts access to the defect area, and therefore, consumes considerable time before anastomosis. For these reasons, the authors consider VSP far more viable in the era of robotic surgery.
Adult ; Carcinoma, Squamous Cell/radiography/*surgery ; Chondrosarcoma/radiography/*surgery ; Female ; Humans ; Imaging, Three-Dimensional ; Mandibular Osteotomy/*methods ; Mandibular Reconstruction/*methods ; Neck Dissection/methods ; Rhytidoplasty ; Robotic Surgical Procedures/*methods ; Robotics/*methods ; Treatment Outcome

BACKGROUND: Along with the advances in technology of three-dimensional (3D) printer, it became a possible to make more precise patient-specific 3D model in the various fields including oral and maxillofacial surgery. When creating 3D models of the mandible and maxilla, it is easier to make a single unit with a fused temporomandibular joint, though this results in poor operability of the model. However, while models created with a separate mandible and maxilla have operability, it can be difficult to fully restore the position of the condylar after simulation. The purpose of this study is to introduce and asses the novel condylar repositioning method in 3D model preoperational simulation. METHODS: Our novel condylar repositioning method is simple to apply two irregularities in 3D models. Three oral surgeons measured and evaluated one linear distance and two angles in 3D models. RESULTS: This study included two patients who underwent sagittal split ramus osteotomy (SSRO) and two benign tumor patients who underwent segmental mandibulectomy and immediate reconstruction. For each SSRO case, the mandibular condyles were designed to be convex and the glenoid cavities were designed to be concave. For the benign tumor cases, the margins on the resection side, including the joint portions, were designed to be convex, and the resection margin was designed to be concave. The distance from the mandibular ramus to the tip of the maxillary canine, the angle created by joining the inferior edge of the orbit to the tip of the maxillary canine and the ramus, the angle created by the lines from the base of the mentum to the endpoint of the condyle, and the angle between the most lateral point of the condyle and the most medial point of the condyle were measured before and after simulations. Near-complete matches were observed for all items measured before and after model simulations of surgery in all jaw deformity and reconstruction cases. CONCLUSIONS: We demonstrated that 3D models manufactured using our method can be applied to simulations and fully restore the position of the condyle without the need for special devices.
Chin ; Congenital Abnormalities ; Equidae ; Glenoid Cavity ; Humans ; Jaw ; Joints ; Mandible ; Mandibular Condyle ; Mandibular Osteotomy ; Maxilla ; Methods ; Oral and Maxillofacial Surgeons ; Orbit ; Orthognathic Surgery ; Osteotomy, Sagittal Split Ramus ; Surgery, Oral ; Temporomandibular Joint

BACKGROUND: Bilateral sagittal split ramus osteotomy (BSSRO) is the most widely used mandibular surgical technique in orthognathic surgery and is easy to relocate the distal segments, accelerating bone repair by the large surface of bone contact. However, it can cause neurosensory dysfunction (NSD) or sensory loss by injury of the inferior alveolar nerve. The purpose of the present study was to evaluate NSD after BSSRO and modifiers at NSD recovery. METHODS: In this study, NSD characteristics after BSSRO from 2009 to 2014 at the Kyung Hee University Dental Hospital were evaluated. The pattern of sensory recovery over time was also evaluated based on factors such as field of sensory dysfunction, surgical procedure, presence of pre-operative facial asymmetry, and postoperative medications. RESULTS: Most of the patients had shown NSD immediately after orthognathic surgery. Among the 1192 sides of 596 patients, NSD was observed in 953 sides and 544 patients. Sexual predilection was shown in males (p value = 0.0062). In the asymmetric group of 132 patients, NSD was observed in 128 patients (96.97%). In the symmetric group of 464 patients, NSD was observed in 416 patients (89.45%); on the other hand, NSD was observed significantly higher in the asymmetric group (p = 0.025). NSD-associated factors were analyzed, and vitamin B12 may be beneficial for NSD recovery. CONCLUSIONS: There was a difference between the symmetric group and the asymmetric group in NSD recovery. Vitamin B12 can be regarded as an effective method to nerve recovery. However, a further prospective study is needed.
Facial Asymmetry ; Hand ; Humans ; Male ; Mandibular Nerve* ; Methods ; Orthognathic Surgery ; Osteotomy, Sagittal Split Ramus* ; Prospective Studies ; Retrospective Studies* ; Vitamin B 12

PURPOSE: To review the 5-year outcomes of our modified mandibulotomy technique. Retrospective review of a tertiary level oral cancer center. MATERIALS AND METHODS: During a 5-year period, 30 patients who had a uniform surgical technique consisting of a lower lip-splitting, modified stair-step osteotomy with thin saw blade and osteotome after plate-precontouring and combination fixation with monocortical osteosynthesis (miniplate) and bicortical osteosynthesis (maxiplate and bicortical screws), with at least 14 months postoperative follow-up, were selected and reviewed retrospectively. RESULTS: There were 8 women and 22 men with an average age of 56.5 years. All the patients involved malignancies were squamous cell carcinoma. The main primary sites of the those who underwent a mandibulotomy were the tonsil, the base of tongue, the oral tongue, the retromolar pad area, and others. Others included buccal cheek, floor of mouth, and soft palate. 23 patients received postoperative radiation therapy, and among whom 8 patients also received chemotherapy. Total four (13%) mandibulotomy-related complications occurred, only two (6.7%) requiring additional operation under general anesthesia. CONCLUSION: Our modified mandibulotomy meets the criteria for an ideal mandibulotomy technique relatively well because it requires no intermaxillary fixation, can precise preserve the occlusion in a precise way, allows early function, requires no secondary procedures, and has few complications.
Adult ; Aged ; Female ; Humans ; Male ; Mandible/*surgery ; Mandibular Osteotomy/adverse effects/*methods/standards ; Middle Aged ; Oropharyngeal Neoplasms/*surgery ; Postoperative Complications/*prevention & control ; Retrospective Studies

OBJECTIVEThe purpose of this study was to determine the incidence of temporary and permanent sensory disturbance of the inferior alveolar nerve (IAN) after bilateral sagittal split osteotomy (BSSO) of the mandible.

METHODS14 patients were selected for this study. Before BSSO and at 1 week, 1, 3, 6 and 12 months after BSSO, the sensibility of bilateral inferior alveolar nerves were examined using sharp-blunt testing, 2-point discrimination, electronic pain response test (ZGK-1 electrometer).

RESULTSWith conventional sharp-blunt and 2-point discrimination test, electronic pain response test, the incidence of temporary impairment of IAN after BSSO was 78% (22/28). Obvious sensory recovery of IAN was found 6 to 12 months postoperatively. Permanent sensory disturbance of unilateral inferior alveolar nerve occurred in 2 patients.

CONCLUSIONSSensory recovery of the inferior alveolar nerve after bilateral sagittal split osteotomy of the mandible would take 6 to 12 months. Serious injury of the IAN would cause permanent neurosensory deficits.

Adolescent ; Adult ; Female ; Humans ; Male ; Mandible ; surgery ; Mandibular Nerve ; physiopathology ; Oral Surgical Procedures ; adverse effects ; Osteotomy ; adverse effects ; methods ; Sensory Thresholds ; Trigeminal Nerve Injuries

OBJECTIVETo explore the method of clinical application and the efficacy of free fibula osteomyocutaneous flap in one-stage reconstruction of transmidline bilateral mandibular defect caused by giant neoplasms.

METHODSFrom july 2000 to october 2002, transmidline bilateral mandibular defects caused by ameloblastoma (4 cases) and gingival carcinoma (2 cases), according to the character of defects, were reconstructed with free fibula osteomyocutaneous flaps. Peroneal artery and vein were used as vascular pedicle, the fibula was reshaped, and micro-titanium plates were used in rigid fixation between fibula and residue of bilateral mandible. Microvascular anastomoses were carried out between peroneal artery/vein and small artery/vein in neck.

RESULTSSix free fibular osteomyocutaneous flaps survived well. Follow up duration ranged from 6 months to 2 years, the lower face appearance recovered well, occlusion relationship were normal, all patients were satisfactory with appearance and chewing function after repair of removable denture.

CONCLUSIONFree fibular osteomyocutaneous flap is a favorable material in the reconstruction of transmidline bilateral mandibular giant defect. The blood supplement of fibula is offered both by segmentral periosteum and nutrient artery from bone marrow, It is greatly benefit to reshaping as arched mandible.

Adult ; Bone Transplantation ; Female ; Fibula ; surgery ; Follow-Up Studies ; Humans ; Male ; Mandible ; surgery ; Mandibular Neoplasms ; surgery ; Osteotomy ; Reconstructive Surgical Procedures ; methods ; Transplantation, Autologous ; Treatment Outcome