Ho Lee

Fracture patterns in the maxillofacial region: a four-year retrospective study.

Objectives The facial bones are the most noticeable area in the human body, and facial injuries can cause significant functional, aesthetic, and psychological complications. Continuous study of the patterns of facial bone fractures and changes in trends is helpful in the prevention and treatment of maxillofacial fractures. The purpose of the current clinico-statistical study is to investigate the pattern of facial fractures over a 4-year period. Materials and Methods A retrospective analysis of 1,824 fracture sites was carried out in 1,284 patients admitted to SMG-SNU Boramae Medical Center for facial bone fracture from January 2010 to December 2013. We evaluated the distributions of age/gender/season, fracture site, cause of injury, duration from injury to treatment, hospitalization period, and postoperative complications. Results The ratio of men to women was 3.2:1. Most fractures occurred in individuals aged between teens to 40s and were most prevalent at the middle and end of the month. Fractures occurred in the nasal bone (65.0%), orbital wall (29.2%), maxillary wall (15.3%), zygomatic arch (13.2%), zygomaticomaxillary complex (9.8%), mandibular symphysis (6.5%), mandibular angle (5.9%), mandibular condyle (4.9%), and mandibular body (1.9%). The most common etiologies were fall (32.5%) and assault (26.0%). The average duration of injury to treatment was 6 days, and the average hospitalization period was 5 days. Eighteen postoperative complications were observed in 17 patients, mainly infection and malocclusion in the mandible. Conclusion This study reflects the tendency for trauma in the Seoul metropolitan region because it analyzes all facial fracture patients who visited our hospital regardless of the specific department. Distinctively, in this study, midfacial fractures had a much higher incidence than mandible fractures.

Pterygoid hamulus bursitis as a cause of craniofacial pain: a case report

Pain on the soft palate and pharynx can originate in several associated structures. Therefore, diagnosis of patients who complain of discomfort in these areas may be difficult and complicated. Pterygoid hamulus bursitis is a rare disease showing various symptoms in the palatal and pharyngeal regions. As such, it can be one of the reported causes of pain in these areas. Treatment of hamular bursitis is either conservative or surgical. If the etiologic factor of bursitis is osteophytic formation on the hamulus or hypertrophy of the bursa, resection of the hamulus is usually the preferred surgical treatment. We report on a case of bursitis that was managed successfully by surgical treatment and a review of the literature.

The postoperative trismus, nerve injury and secondary angle formation after partial masseter muscle resection combined with mandibular angle reduction: a case report

A patient, who underwent partial masseter muscle resection and mandibular angle reduction at a plastic surgery clinic, visited this hospital with major complaints of trismus and dysesthesia. A secondary angle formation due to a wrong surgical method was observed via clinical and radiological examinations, and the patient complained of trismus due to the postoperative scars and muscular atrophy caused by the masseter muscle resection. The need for a masseter muscle resection in square jaw patients must be approached with caution. In addition, surgical techniques must be carefully selected in order to prevent complications, and obtain effective and satisfactory surgery results.

The Influential Bony Factors and Vectors for Predicting Soft Tissue Responses After Orthognathic Surgery in Mandibular Prognathism

PURPOSEnWe sought to identify the hard tissue points and vectors that have the greatest effect on soft tissue movement after orthognathic surgery in patients with mandibular prognathism.nnnPATIENTS AND METHODSnThe present retrospective study involved patients who had undergone mandibular setback surgery with or without maxillary advancement. Multiple linear regression models were adapted to evaluate the association between the 8 hard tissue landmark (predictor variables) changes and 11 soft tissue responses (outcome variables) using the x and y coordinates assessed from superimposed pre- and postoperative 3-dimensional computed tomography images.nnnRESULTSnA total of 50 patients (42 patients had undergone 2-jaw surgery; 8 patients had undergone 1-jaw surgery; mean age 23xa0±xa04xa0years) were included in the present study. Our statistical models demonstrated that the horizontal hard tissue changes had a greater influence on the soft tissue responses than did the vertical changes, and these changes were more notable in the lower facial area (lower lip contour and chin profile) than the midfacial area (nasal profile, upper lip contour, upper lip length, and nasolabial angle). In the horizontal soft tissue response model, the soft tissue A point/A point ratio was 0.86:1 (95% confidence interval [CI] 0.674-1.049); the soft tissue B point/B point ratio was almost 1:1 (95% CI 0.919-1.071); and the soft tissue pogonion/pogonion ratio was 0.88:1 (95% CI 0.805-0.963).nnnCONCLUSIONSnHorizontal or vertical bone tissue changes affected both the horizontal and vertical soft tissue changes in most areas. Our study demonstrated that the soft tissue response is not linear but a more complicated and dynamic reaction.

Fate of mandibular canals displaced by enlarged cystic lesions: does the inferior alveolar neurovascular bundle relocate to its original position?

Our aim was to identify the positional changes of the inferior alveolar neurovascular bundle and evaluate the relocation of the displaced mandibular canal after enucleation of a cyst. Seventy patients (72 sites) who had had cysts enucleated were divided into three groups based on the degree of encroachment of the cystic lesion into the mandibular canal and whether a bone graft had been inserted after the cyst had been enucleated. The mean (range) of patients ages was 45 (18-75) years, and there were 29 male and 41 female patients. Group A comprised cysts with encroachment on the mandibular canal that were enucleated without a bone graft; Group B consisted of cysts with no encroachment of the mandibular canal, but were enucleated without a bone graft; and Group C comprised cysts with encroachment of the mandibular canal that were enucleated with a bone graft. The displacement of the mandibular canal was identified from analysis of computed tomographic (CT) images. Changes in the position of the mandibular canal were measured on panoramic radiographs. The mandibular canal was repositioned superiorly by a mean (SD) of 2.4 (1.65)mm after enucleation of the cyst, which was significant in Group A (p<0.001), but not in Groups B and C. These results indicate that the displaced inferior alveolar neurovascular bundles that were not surrounded by bony canal tended to relocate towards a supposedly normal position, and after enucleation of the cyst the mandibular canal was remodelled in this new location. This tendency to relocate was blocked by bone grafting. Bone grafts are therefore recommended in cases where enough bony height is required for future insertion of implants.

Valproic Acid Modulates the Multipotency in Periodontal Ligament Stem Cells via p53-Mediated Cell Cycle

Human periodontal ligament stem cells (PDLSCs), a type of mesenchymal stem cell, are a promising source for dental regeneration and are identified in human periodontal ligaments from extracted third molars. Valproic acid (VPA) is a histone deacetylase inhibitor that has been used as a wide-spectrum antiepileptic drug and a medication for mood disorders. VPA has shown several effects on increasing the pluripotency of embryonic stem cells and controlling osteogenic differentiation, besides the prevention of seizures. However, its effect on proliferation and osteogenesis depends on the cell type and concentration. The aim of this study was to investigate the effects of cyclic and constant VPA treatment on PDLSCs. Proliferation and apoptosis of PDLSCs were determined with cyclic and constant VPA treatment. In cemento/osteogenic differentiation, osteogenic markers decreased significantly after cyclic treatment with 0.5 mM VPA. In contrast, VPA enhanced osteogenic differentiation after constant treatment. With cyclic VPA treatment, p53 levels related to apoptotic pathway decreased to induce proliferation. These findings indicated that VPA has different roles in proliferation and differentiation of PDLSCs in vitro and in vivo via p53-related pathway.

Risk factor analysis of additional administration of sedative agent and patient dissatisfaction in intravenous conscious sedation using midazolam for third molar extraction

Objectives The primary purpose of this study was to investigate the factors related with additional administration of sedative agent during intravenous conscious sedation (IVS) using midazolam (MDZ). The secondary purpose was to analyze the factors affecting patient satisfaction. Materials and Methods Clinical data for 124 patients who had undergone surgical extraction of mandibular third molar under IVS using MDZ were retrospectively investigated in this case-control study. The initial dose of MDZ was determined by body mass index (BMI) and weight. In the case of insufficient sedation at the beginning of surgery, additional doses were injected. During surgery, peripheral oxygen saturation, bispectral index score (BIS), heart rate, and blood pressure were monitored and recorded. The predictor variables were sex, age, BMI, sleeping time ratio, dental anxiety, Pederson scale, and initial dose of MDZ. The outcome variables were additional administration of MDZ, observers assessment of alertness/sedation, intraoperative amnesia, and patient satisfaction. Descriptive statistics were computed, and the P-value was set at 0.05. Results Most patients had an adequate level of sedation with only the initial dose of MDZ and were satisfied with the treatment under sedation; however, 19 patients needed additional administration, and 13 patients were unsatisfied. In multivariable logistic analysis, lower age (odds ratio [OR], 0.825; P=0.005) and higher dental anxiety (OR, 5.744; P=0.003) were related to additional administration; lower intraoperative amnesia (OR, 0.228; P=0.002) and higher BIS right before MDZ administration (OR, 1.379; P=0.029) had relevance to patient dissatisfaction. Conclusion The preoperative consideration of age and dental anxiety is necessary for appropriate dose determination of MDZ in the minor oral surgery under IVS. The amnesia about the procedure affects patient satisfaction positively.

Malocclusion after open reduction of midfacial fracture: a case report

Malocclusion is a serious complication of open reduction surgery for facial fractures. It is often caused by the lack of adequate consideration for the occlusal relationship before the trauma and intermaxillary fixation during the operation. This is a case report of postoperative malocclusion that occurred in a patient with a midfacial complex fracture.

Association between orthodontic treatment and periodontal diseases: Results from a national survey

OBJECTIVEnTo investigate the association between orthodontic treatment and periodontitis in a nationally representative sample of South Korea.nnnMATERIALS AND METHODSnData from the Fifth and Sixth Korean National Health and Nutrition Examination Survey (KNHANES V, VI-1, and VI-2), conducted from 2012 to 2014, were used in this study. The final sample size consisted of 14,693 adults aged ≥19 years. Logistic regression analysis was performed to assess the association between orthodontic treatment and periodontitis.nnnRESULTSnThe orthodontic treatment group exhibited a lower prevalence of periodontitis compared with the nonorthodontic treatment group. The adjusted odds ratios for periodontitis in subjects with a history of orthodontic treatment compared with those with no history of orthodontic treatment were 0.553, 0.614, and 0.624, when adjusted for various confounding variables (P < .0001). The subjects with periodontitis were of higher age, body mass index, waist circumference, and white blood cell counts compared with the subjects without periodontitis regardless of history of orthodontic treatment.nnnCONCLUSIONSnHistory of orthodontic treatment was associated with a decreased rate of periodontitis.