• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.43 no.3
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• pp.152-159
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• 2017

Objectives: The aim of this study was to investigate the effects of advancement magnitude and changes in mandibular plane angle on the stability of mandibular advancement. Materials and Methods: This retrospective cohort study evaluated the postoperative stability of mandibular advancement in class II skeletal subjects who underwent bilateral sagittal split osteotomy. Radiographs taken preoperatively, immediately postoperatively and 1 year postoperatively were traced and analyzed using linear and angular measurements. To determine horizontal and vertical relapse, an X-Y coordinate system was established in which the X-axis was constructed by rotating S-N downward by $7^{\circ}$ (approximation of the Frankfort horizontal plane) and the Y-axis was defined as a line perpendicular to the X-axis and passing through the point Sella. For certain reference points including point A, point B, pogonion and menton, the perpendicular distance between each point and both axes was determined and cephalometric variables were recorded as X and Y coordinates. Results: Twenty-five subjects were studied. A significant correlation between the amount of mandibular advancement and relapse in the B point (vertical and horizontal) and the pogonion point was observed (vertical and horizontal, P<0.001). Evaluation of data demonstrated a positive correlation between the mandibular plane angle (SN/ML) change and vertical relapse in the B point (P<0.05). A simple regression model demonstrated that 74% of horizontal relapse and 42.3% of vertical relapse in the B point was related to the amount of mandibular advancement. The receiver operating characteristic test showed that 8.5 mm mandibular advancement is related to a relapse rate of 1 mm or more in the pogonion, vertically or horizontally. Conclusion: The magnitude of mandibular advancement is a stronger surgical predictor for horizontal rather than vertical relapse at the B point. Changes in mandibular plane angle (SN/ML) during surgery affect vertical, but not horizontal relapse at the B point.

• The korean journal of orthodontics
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• v.40 no.2
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• pp.115-126
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• 2010

This case report describes the treatment of a 66 year old adult patient with a diagnosis of severe obstructive sleep apnea who was intolerant of nasal continuous positive airway pressure (nCPAP) treatment and oral appliance therapy. An alternative treatment of snoring and obstructive sleep apnea (OSA) with 2 orthodontic microimplants anchored to the mandible providing skeletal anchorage for mandibular advancement was implemented. After a 2 week healing period, a custom designed facemask provided extraoral anchorage to which the microimplants were connected to for titratable mandibular advancement. Microimplant Mandibular Advancement (MiMA) therapy resulted in resolution of the symptoms of severe OSA with a reduction of the apnea-hypopnea index (AHI), snoring and OSA symptoms.

• Journal of Oral Medicine and Pain
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• v.39 no.2
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• pp.35-45
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• 2014

Many therapeutic modalities including continuous positive airway pressure, surgery, and oral appliances are used to treat patients with sleep-disordered breathing. However, there are no definitive treatment modalities for individual patients due to various causes of sleep-disordered breathing. Clinicians should have select best options for individual patients and it is quite challenging process. Oral appliances attracted clinical attention for its convenience and safety. Several designs of oral appliances are introduces such as soft palate lifter, tongue retaining device, and various appliances which aimed to mandibular advancement. Among these oral appliances, mandibular advancement devices (MADs) are considered the most excellent based on their effectiveness and patient tolerance. Although MADs are not guarantee dramatic outcome and less consistent than continuous positive airway pressure, they offer several advantages over continuous positive airway pressure and surgical methods, including non-invasiveness, silence, portability, and tolerability, simplicity. Therefore, general dental practitioner who had passed sleep dental curriculum or coursework can treat the patients with sleep problems. This article reviews the history, clinical indications, suggested mechanism of actions, various positive effects and several side effects, factors predicting a favorable outcome, determining amounts of mandibular advancement, compliance and long-term efficacy of MADs use.

• The Journal of the Korean dental association
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• v.38 no.7 s.374
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• pp.664-671
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• 2000

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.2
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• pp.94-99
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• 2010

The purpose of this study was to examine the soft tissue changes in skeletal class II patients after mandibular advancement by bilateral sagittal split ramus osteotomy (BSSRO). In Asian population, the incidence of skeletal class II malocclusion is lower than that of skeletal class III malocclusion unlike the caucasians. This study was conducted to figure out the ratio at which hard tissue and soft tissue changes after mandibular advancement by analyzing cephalograms of 13 patients that have undergone the mandibular advancement surgery. As a result, change ratios of Li, B', Pog' according to the movement of li, B, Pog were found to be 0.59, 1.06, 0.82. Also, vertical height of vermilion zone (Si-Vb) and lower lip and chin (Si-Me') were measured to evaluate vertical changes. Vermilion zone showed tendency to decrease by 1.02 mm on the average postoperatively, whereas vertical length of lower lip and chin showed tendency to increase by 3.57 mm on the average.

• Sleep Medicine and Psychophysiology
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• v.18 no.1
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• pp.29-34
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• 2011

Objectives: The purposes of this study were to estimate the effect of mandibular advancement device (MAD) and to evaluate the influence of the advancement amount of mandible in the application of MAD for obstructive sleep apnea (OSA) patients. Methods: From the patients who were diagnosed as OSA by polysomnographic study at Seoul National University Bundang Hospital from January 2007 to February 2009, the patients who chose MAD as treatment option were included in this study. All the patients’ data including clinical records and polysomnographic studies (both pre- and post-treatment) were reviewed and analyzed. Results: Successful results were obtained in 65 patients of 86 patients (75.6%). In the follow-up period, mild discomfort of anterior teeth or temporomandibular joint (TMJ) were described in 28 patients, especially in the cases the amount of mandibular advancement were more than 7.0 mm. There was no direct relationship between the amount of mandibular advancement and clinical outcome. Conclusion: MAD was effective treatment option for the OSA patients regardless of severity. For the prevention of potential dental complications, the amount of mandibular advancement should be considered at the time of MAD treatment.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.3
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• pp.217-226
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• 2007

Purpose: Distraction osteogenesis is considered to take favorable effect on the TMJ and be beneficial to prevent the relapse after the mandibular advancement of Class II malocclusion patient. This is the report with literature review on the mandibular advancement in the patients showing preoperative condylar resorption and who need larger amount of advancement. Patients and method: Distraction osteogenesis using intraoral device was performed for three mandibular hypoplasia patients (one male and two females). All patients were adult over 18 years old. The patients showed condylar bony resorption preoperatively. The distraction was performed intraorally with modified SSRO. After 7 days of latency period, activation was performed at the rate of 1.0 mm/day with twice turn. The devices were removed after 4-8 month consolidation period. Results: Total advancement of mandible was average 13 mm. One patient showed openbite immediately after removal of distraction device. It took long time to guide the openbite with elastics. The comparison between cephalometries immediately after device removal and postoperative six month revealed average 3.4 mm relapse. This means that mandibular advancement with distraction osteogenesis needs overcorrection and elastic rehabilitation even after enough consolidation periods. Conclusion: Larger amount of mandibular advancement could be achieved with distraction osteogenesis in severe mandibular hypoplasia with condylar resorption. However, some relapse was found during the follow-up period and the over correction is considered to be needed. The effect of distraction osteogenesis seems to be investigated with long-term follow-up.

• The korean journal of orthodontics
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• v.49 no.4
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• pp.265-276
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• 2019

Patients with obstructive sleep apnea (OSA) whose phenotype belongs to a craniofacial vulnerability are referred from sleep doctors to orthodontists. In adults, for osseo-pharyngeal reconstruction (OPR) treatment, permanent maxillomandibular advancement (MMA) surgery and use of a temporary mandibular advancement device (MAD) are applied. This case report demonstrates successful treatment of OSA through application of phased MAD and MMA in a 16-year-old male with craniofacial deformity and residual growth potential. This patient showed skeletal and dentoalveolar changes after 7-year MAD use throughout post-adolescence, which affected the design and timing of subsequent MMA surgery, as well as post-surgical orthodontic strategy. This case report suggests that OPR treatment can be useful for treatment of OSA in post-adolescent patients, from an orthodontic point of view, in close collaboration with sleep doctors for interdisciplinary diagnosis and treatment.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.2
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• pp.100-105
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• 2012

Purpose: In general, the surgical treatment for mandibular retrognathism is represented by two methods, distraction osteogenesis (DO) and mandibular osteotomy surgery. The DO is mostly preferred when the degree of advancement of mandible is large. However, the postoperative stability of mandibular advancement using DO have not been actively investigated. Therefore, in the present study we have compared the postoperative stability between DO and bilateral sagittal split ramus osteotomy (BSSRO) in mandibular retrognathism. Methods: Seven patients who had been treated by DO and thirteen patients with BSSRO were included in this study. Serial lateral cephalograms were analyzed by manual tracing and the amount of the mandibular elongation was measured. To evaluate the postoperative stability, positional changes of the condylar position and B point were analyzed. Results: Mean amount of mandibular advancement was $6.51{\pm}3.57mm$ for BSSRO group and $12.43{\pm}4.35mm$ for DO group, respectively. There was no significant difference in age between the two groups (P>0.05). Mean follow up periods were 10.77 months for BSSRO group and 11.28 months for DO group, respectively. After mandibular advancement, mean positional changes in the condyle were $0.56{\pm}1.43mm$ horizontally and $0.72{\pm}1.61mm$ vertically for BSSRO group and $0.53{\pm}1.56mm$ horizontally and $0.56{\pm}1.75mm$ vertically for DO group, respectively. Mean change of distance from B point to Y-axis was $-1.76{\pm}0.83mm$ for BSSRO group and $-2.14{\pm}1.82mm$ for DO group, respectively. According to the condylar position and B point, there were no significant differences in postoperative stability between the two groups (P>0.05). Conclusion: There was no significant difference in postoperative stability between DO and BSSRO group according to condylar position and B point. Based on the results of the present study, it is hypothesized that DO would be a good treatment choice for severe mandibular retrognathism because DO could achieve more mandibular advancement and concurrent soft tissue elongation.

• The Journal of the Korean dental association
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• v.53 no.4
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• pp.259-265
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• 2015

Recently, oral appliances for treating snoring and obstructive sleep apnea are widely used. Among various appliances, mandibular advancement devices are most effective without serious side effects. Advancement of mandible keep airway open and decrease snoring and/or obstructive apnea events. They can be used as stand-alone therapy or an adjunct to continuous positive air pressure for lowering air pressure. Oral appliances should be applied by dentists who have knowledges and experiences on occlusion and temporomandibular disorders and manage of side effects.