• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제27권6호
• /
• pp.535-544
• /
• 2005

The management of mandibular condyle fractures continues to be a subject of much debate. It is suggested that, if not properly managed, these fractures may give rise to serious problems, such as malocclusion, mouth opening limitation, temporomandibular joint disorders. Treatment planing of mandibular condyle fractures is very important. The aim of this present study was to evaluate the long-term results according to treatment methods in condylar fractures. Also, it was to evaluate results of treatment according to condylar fracture level. We conducted a retrospective analysis of 43 mandibular condyle fractures. 43 patients followed for average period of 9.00 years(mini. 7yr, max. 12yr). All patients underwent a clinical and radiologic evaluation focusing on mouth opening, mandibular movements, TMJ function, change of ramal height, condylar remodelling. If the level of fracture was positioned in high, especially in level II, mandibular movement disability and ramus length loss was more prominent. This results were similar to the cases of treatment of fragment removal. In high level fracture and fragment removal cases, It is thought that more intensive and long term management are needed than other treatment cases using different operation methods. Also, direct fixation by each approach showed good results in mandibular movement, ramal height change and condylar shape. Through this results, accurate reduction of the mandibular condyle fractures was a very important factor in postoperative prognosis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제34권4호
• /
• pp.460-467
• /
• 2008

Pierre Robin sequence as a symptom triad of micrognathia, glossoptosis, and cleft palate results in upper airway obstruction and feeding problems. If mild, it is often managed in the prone position. When positional treatment fails, however, surgical intervention such as tongue-lip adhesion, tracheostomy, and mandibular distraction osteogenesis is mandatory to relieve airway obstruction. There has been growing interest in the application of distraction osteogenesis for the management of craniofacial abnormalities. The mandibular distraction osteogenesis to newborns may prevent the airway obstruction, decrease the potential tracheostomy, and reduce the likehood of orthognathic surgery after growth. We experienced an infant with Pierre Robin sequence who showed mandibular hypoplasia, glossoptosis, incomplete cleft palate, intermittent cyanos is, depression of the chest, and respiratory difficulty associated with airway obstruction. We treated the airway obstruction by tongue-lip adhesion at 2 weeks of age, and treated the mandibular retrognathism and depression of the chest byusing internal mandibular distraction osteogenesis at 7 month of age. The mandible moved forwardly, the upper airway space was enlarged, and the antero-posterior distance of the mandible was elongated after the mandibular distraction. Mandibular distraction osteogenesis may be a promising technique to avoid the need of tracheostomy and orthognathic surgery, and to correct airway obstruction in infants with congenital craniofacial malformation.

• Imaging Science in Dentistry
• /
• 제51권1호
• /
• pp.17-25
• /
• 2021

Purpose: This study was performed to investigate mandibular canal displacement in patients with ameloblastoma using a 3-dimensional mirrored-model analysis. Materials and Methods: The sample consisted of computed tomographic scans of patients with ameloblastoma (n=10) and healthy controls (n=20). The amount of mandibular canal asymmetry was recorded as a continuous variable, while the buccolingual (yaw) and supero-inferior (pitch) directions of displacement were classified as categorical variables. The t-test for independent samples and the Fisher exact test were used to compare groups in terms of differences between sides and the presence of asymmetric inclinations, respectively (P<0.05). Results: The length of the mandibular canal was similar on both sides in both groups. The ameloblastoma group presented more lateral (2.40±4.16 mm) and inferior (-1.97±1.92 mm) positions of the mental foramen, and a more buccal (1.09±2.75 mm) position of the middle canal point on the lesion side. Displacement of the mandibular canal tended to be found in the anterior region in patients with ameloblastoma, occurring toward the buccal and inferior directions in 60% and 70% of ameloblastoma patients, respectively. Conclusion: Mandibular canal displacement due to ameloblastoma could be detected by this superimposed mirrored method, and displacement was more prevalent toward the inferior and buccal directions. This displacement affected the mental foramen position, but did not lead to a change in the length of the mandibular canal. The control group presented no mandibular canal displacement.

• 대한치과교정학회지
• /
• 제51권3호
• /
• pp.179-188
• /
• 2021

Objective: To evaluate the overall treatment effects in terms of the amount of uprighting with changes in the sagittal and vertical positions of mandibular molars after applying an orthodontic miniplate with a nickel-titanium (NiTi) reverse curve arch wire (biocreative reverse curve [BRC] system). Methods: A total of 30 female patients (mean age, 25.99 ± 8.96 years) were treated with the BRC system (mean BRC time, 10.3 ± 4.07 months). An I-shaped C-tube miniplate (Jin Biomed) was placed at the labial aspect for the alveolar bone of the mandibular incisors. A 0.017 × 0.025-inch NiTi reverse curve arch wire was engaged at the C-tube mini-plate anteriorly and the first and second premolars and molars posteriorly in the mandibular arch. Pre- and post-BRC lateral cephalograms were analyzed. A paired t-test was used to analyze the treatment effects of BRC. Results: The mandibular second molars were intrusively uprighted successfully by the BRC system. Distal uprighting with a controlled vertical dimension was noted on the first molars when they remained engaged in the BRC and the distal ends of the arch wire were laid on the second molars. The mandibular first and second premolars showed a slight extrusion. The changes in the mandibular incisors were unremarkable, while the mandibular molar angulation improved significantly. The lower occlusal plane rotated counterclockwise (MP-LOP: 1.13° ± 2.60°). Conclusions: The BRC system can provide very effective molar uprighting without compromising the position of the mandibular anterior teeth.

• 대한치과교정학회지
• /
• 제19권1호
• /
• pp.77-93
• /
• 1989

The purpose of the present study were to disclose whether the depth of the mandibular antegonial notch can be used as an indicator of mandibular growth potential. The patients composed of 76 samples and were classified following 3 groups, based on the depth of mandibular antegonial notch : Deep notch group (more than 3mm), Neutral notch group (1-3mm), Shallow notch group (less than 1mm). For each case, the first lateral cephalograms were taken prior to the start of treatment and the second films 3-4 years after. The results were as follows; 1. Deep notch group had a shorter corpus, less ramus height and greater genial angle than did Shallow notch group. 2. Deep notch group had a more retrusive mandibular position than Shallow notch group. 3. Deep notch group had longer total anterior facial height and longer anterior lower facial height group. 4. Deep notch group grow vertical clockwise growth pattern, while Shallow notch group grow horizontal counterclockwise growth pattern. 5. Deep notch group had less mandibular growth than Shallow notch group during observation period.

• 대한치과교정학회지
• /
• 제35권1호
• /
• pp.82-89
• /
• 2005

하악 이부 확장은 해부학적으로 가동성인 하악골에서 시행하는 견인골 신장술의 한 형태로 곡면화된 표면과 하악 과두, 좁은 치열궁 형태로 많은 제약을 받게 된다. 본 연구는 이러한 한계를 보완하기 위해 적용되는 다양한 형태의 이부 확장을 이해하기 위해 시도되었다 골 절단선의 위치와 견인 장치의 위치를 다르게 하여. 각 8가지 군으로 구분한 후 이부 확장을 시행하였다. 이부 확장은 견인기의 위치와 골 절단선의 형태에 따라 다르게 이루어지는 결과를 얻었다.

• Imaging Science in Dentistry
• /
• 제33권4호
• /
• pp.199-205
• /
• 2003

Purpose: To compare the visibility of the mandibular canal at the different radiographic methods such as conventional panoramic radiographs, Vimplant multi planar reformatting (MPR)-CT panoramic images, Vimplant MPR-CT paraxial images and film-based DentaScan MPR-CT images. Materials and Methods: Data of 11 mandibular dental implant patients, who had been planned treatment utilizing both panoramic and MPR-CT examination with DentaScan software (GE Medical systems, Milwaukee, USA), were used in this study. The archived axial CT data stored on CD-R discs were transferred to a personal computer with 17' LCD monitor. Paraxial and panoramic images were reconstructed using Vimplant software (CyberMed Inc., Seoul, Korea). Conventional panoramic radiographs, monitor-based Vimplant MPR-CT panoramic images, monitor-based Vimplant MPR-CT paraxial images, and film-based DentaScan MPR-CT images were evaluated for visibility of the mandibular canal at the mental foramen, 1 cm, 2 cm, and 3 cm posterior to mental foramen using the 4-point grading score. Results: Vimplant MPR-CT panoramic, paraxial, and DentaScan MPR-CT images revealed significantly clearer images than conventional panoramic radiographs. Particularly at the region 1 em posterior to mental foramen, conventional panoramic radiographs showed a markedly lower percentage of 'excellent' mandibular canal images than images produced by other modalites. Vimplant MPR-CT and DentaScan MPR-CT images did not show significant difference in visibility of the mandibular canal. Conclusion: The study results show that Vimplant and DentaScan MPR-CT imaging systems offer significantly better images of the mandibular canal than conventional panoramic radiograph.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제33권1호
• /
• pp.32-35
• /
• 2011

Purpose: Mandibular angle fractures constitute approximately 30% of mandibular fractures, and the mandibular third molar is usually in line with the fracture. This study evaluated the relationship between the extraction of a tooth in line with a mandibular angle fracture and the infection rate. Methods: One hundred and forty seven patients with mandibular angle fractures containing a tooth in line with the fracture from 2005 to 2008 were enrolled in this study. The patients were divided into two groups based on an extraction, and the infection rates were evaluated in both groups. Results: An extraction was performed in 70 patients (47.6%) and postoperative infections occurred in 14 patients (9.5%). Six (8.6%) of the 70 patients in the extraction group and 8 (10.4%) of the 77 patients in the non-extraction group had an infection. There was no significant difference between the two groups (P=0.708). Conclusion: These results show that there is no increased risk of postoperative complications when a tooth is present

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제30권6호
• /
• pp.530-535
• /
• 2004

Objectives. The purpose of this study was to evaluate mandibular third molars as risk factors for angle fracture in a patient sample with fractured mandible. Materials and methods. The medical records and panoramic radiographs of 107 patients with mandibular fractures were examined. The presence and absence and degree of impaction of the lower third molar were assessed for each patient and related to the occurrence of fracture of the mandibular angle. Data were also collected for age, sex and mechanism of injury. Data were analyzed by a chisquare statistics and Student t test. Result. The incidence of mandibular angle fracture was found to be significantly greater when a lower third molar was present(p <0.05) especially at class III state.(p < 0.05)(by Pell & Gregory system) Of the 78 patients with a lower third molar, 46(58.97%) had angle fractures. Of the 29 without a lower third molar, 24(82.76%) had not angle fractures. Conclusion. The result of this study showed that the mandibular angle that have a lower third molar is more susceptible to fracture when exposed to an impact than an angle without an lower third molar.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제23권4호
• /
• pp.348-356
• /
• 2001

The factors related to relapse in 20 skeletal class III patients who performed two-jaw surgery with Le Fort I maxillary osteotomy and bilateral sagittal split ramus osteotomy was investigated. All patients were fixed with miniplate on the maxilla and three screws at each mandible. Cephalograms taken at preoperative, immediate postoperative and 8 months postoperative after surgery were traced and digitized. 1.The horizontal and vertical relapse of maxilla and mandibular chin points was within 1mm postoperatively. Compare to the preceding report concerning the mandibular set-back surgery only group, this reveals two-jaw surgery for mandibular prognathism using rigid fixation is more stable. 2.Although there was no significant relapse tendancy was observed at chin points, the screw tip land-marks moves anterio-superiorly and each side of the screws moved as a one unit. The screw tip points moved similar direction to the masticatory force and this movements might be influenced by the muscular tension to the distal segment of the mandible. 3.According to the regression analysis, the amount of horizontal and vertical movement of mandibular set-back influenced the mandibular relapse. However, direction and amount of maxillary surgical movement did not inf1uenced the maxillary and mandibular relapse.