Yu-Ray Chen

Chang Gung Memorial Hospital, T’ai-pei, Taipei, Taiwan

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Publications (114)167.21 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this prospective study was to compare the mandibular range of motion in Class III patients with and without early physiotherapy after orthognathic surgery (OGS). This study consisted of 63 Class III patients who underwent 2-jaw OGS. The experimental group comprised 31 patients who received early systematic physical rehabilitation. The control group consisted of 32 patients who did not have physical rehabilitation. Twelve variables of 3-dimensional (3D) jaw-motion analysis (JMA) were recorded before surgery (T1) and 6 weeks (T2) and 6 months (T3) after surgery. A 2-sample t test was conducted to compare the JMA results between the two groups at different time points. At T2, the JMA data were measured to be 77.5%–145.7% of presurgical values in the experimental group, and 60.3%–90.6% in the control group. At T3, the measurements were 112.2%–179.2% of presurgical values in the experimental group, and 77.6%–157.2% in the control group. The patients in the experimental group exhibited more favorable recovery than did those in the control group, from T1 to T2 and T1 to T3. However, after termination of physiotherapy, no significant difference in the extent of recovery was observed between groups up to 6 months after OGS.
    Journal of Cranio-Maxillofacial Surgery 11/2014; · 2.60 Impact Factor
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    ABSTRACT: The study was conducted to evaluate the effect of early physical rehabilitation by comparing the differences of surface electromyographic (sEMG) activity in the masseter and anterior temporalis muscles after surgical correction of skeletal class III malocclusion. The prospective study included 63 patients; the experimental groups contained 31 patients who received early systematic physical rehabilitation; the control group (32 patients) did not receive physiotherapy. The amplitude of sEMG in the masticatory muscles reached 72.6–121.3% and 37.5–64.6% of presurgical values in the experimental and control groups respectively at 6 weeks after orthognathic surgery (OGS). At 6 months after OGS, the sEMG reached 135.1–233.4% and 89.6–122.5% of presurgical values in the experimental and control groups respectively. Most variables in the sEMG examination indicated that recovery of the masticatory muscles in the experimental group was better than the control group as estimated in the early phase (T1 to T2) and the total phase (T1 to T3); there were no significant differences between the mean recovery percentages in the later phase (T2 to T3). Early physical rehabilitative therapy is helpful for early recovery of muscle activity in masticatory muscles after OGS. After termination of physical therapy, no significant difference in recovery was indicated in patients with or without early physiotherapy.
    Journal of Cranio-Maxillofacial Surgery 11/2014; · 2.60 Impact Factor
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    ABSTRACT: The surgery-first approach in orthognathic surgery has recently created a broader interest in completely eliminating time-consuming preoperative orthodontic treatment. Available evidence on the surgery-first approach should be appraised to support its use in orthognathic surgery. A MEDLINE search using the keywords "surgery first" and "orthognathic surgery" was conducted to select studies using the surgery-first approach. We also manually searched the reference list of the selected keywords to include articles not selected by the MEDLINE search. The search identified 18 articles related to the surgery-first approach. There was no randomized controlled clinical trial. Four papers were excluded as the content was only personal opinion or basic scientific research. Three studies were retrospective cohort studies in nature. The other 11 studies were case reports. For skeletal Class III surgical correction, the final long-term outcomes for maxillofacial and dental relationship were not significantly different between the surgery-first approach and the orthodontics-first approach in transverse (e.g., intercanine or intermolar width) dimension, vertical (e.g., anterior open bite, lower anterior facial height) dimension, and sagittal (e.g., anterior-posterior position of pogonion and lower incisors) dimension. Total treatment duration was substantially shorter in cases of surgery-first approach use. In conclusion, most published studies related to the surgery-first approach were mainly on orthognathic correction of skeletal Class III malocclusion. Both the surgery-first approach and orthodontics-first approach had similar long-term outcomes in dentofacial relationship. However, the surgery-first approach had shorter treatment time.
    Biomedical journal. 07/2014; 37(4):184-90.
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    ABSTRACT: Maxillomandibular advancement (MMA) is effective in the treatment of obstructive sleep apnoea. We aimed to assess changes in the calibre of the upper airway, facial skeleton, and surrounding structural position after MMA and their association with improvement in symptoms. Sixteen consecutive adults with moderate-to-severe apnoea were treated by primary MMA. Polysomnography and computed tomography (CT) of the head and neck were done before and at least 6 months after MMA. The calibre of the upper airway, the facial skeleton, and the surrounding structures were measured with image analysis software. After MMA, patients had a significant reduction in their apnoea-hypopnoea index (31.2 (18.8) number of events (n)/hour (h)). The mean (SD) volume of the airway increased significantly in the velopharynx (p < 0.01), oropharynx (p = 0.001), and hypopharynx (p < 0.001) (by 2.3 (2.4), 2.1 (2.6), and 1.7 (1.1) cm3, respectively) and the length of the airway was significantly decreased (by 3.1 (3.5) mm p < 0.01). The soft palate (p < 0.001), tongue (p < 0.001), and hyoid (p = 0.001) moved significantly anteriorly (by 4.4 (2.0), 7.5 (2.8), and 5.7 (5.0) mm, respectively), and these movements were related to the MMA (r = 0.6–0.8). The improvement in the apnoea-hypopnoea index was associated with both maxillary advancement and anterior movements of the soft palate and hyoid (r = 0.6–0.7). The results of this study suggest that MMA increases the volume in the upper airway and reduces its length. Improvement in obstructive sleep apnoea is associated with the extent of the anterior movements of the maxilla, soft palate, and hyoid.
    British Journal of Oral and Maxillofacial Surgery 05/2014; · 1.13 Impact Factor
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    Annals of Plastic Surgery 12/2013; 2013(71):S8-S12. · 1.46 Impact Factor
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    ABSTRACT: Background: Although the appropriate management of condylar process fractures after miniplate or microplate fixation has been described, there has been no comparative analysis of these plating systems. Methods: A retrospective review of patients who underwent open reduction and internal fixation (ORIF) of condylar head or neck fractures at our institution from January 2000 through August 2010 identified 70 patients. Of these, 38 were treated with microplates and 32 with miniplates. The primary functional and radiographic results were the maximal mouth opening and con-dylar bone resorption, respectively. The rates of complications, including mal-occlusion, chin deviation, temporomandibular joint complaints, and facial nerve palsy, were recorded. Results: The maximal mouth opening was larger in the microplate group than in the miniplate group throughout the follow-up period; this difference was statistically significant 12 (P = 0.020), 18 (P = 0.026), and 24 (P = 0.032) months after ORIF. Similarly, the radiographic scores for bone resorption and condyle morphology were significantly better in the microplate group than in the miniplate group throughout the follow-up period [6 (P = 0.011), 12 (P = 0.035), 24 (P = 0.026), and 48 (P = 0.040) months after ORIF]. Moreover, patients who underwent miniplate fixation experienced a signifi-cantly higher incidence of temporomandibular joint click than those who underwent microplate fixation (P = 0.014). Conclusions: Microplates limit dissection, providing excellent fixation for intracapsular condylar head fractures, and also provide adequate rigidity for fixation of condylar neck fractures. Microplate fixation of condylar head and neck fractures yielded excellent functional and radiographic results. The rates of complications after microplate fixation were equal to or less than those in the miniplate group. Prospective studies are needed to confirm these findings.
    Annals of Plastic Surgery 12/2013; 71(supplement):s61. · 1.46 Impact Factor
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    ABSTRACT: Craniofacial Neurofibromatosis is a benign but devastating disease. While the most common location of facial involvement is the orbito-temporal region, patients often present with significant mid-face deformities. We reviewed our experience with Craniofacial Neurofibromatosis from June 1981 to June 2011 and included patients with midface soft tissue deformities defined as gross alteration of nasal or upper lip symmetry. Data reviewed included the medical records and photobank. Over 30 years, 52 patients presented to and underwent surgical management for Craniofacial Neurofibromatosis at the Chang Gung Craniofacial Center. 23 patients (43%) demonstrated gross mid-facial deformities at initial evaluation. 55% of patients with lip deformities and 28% of patients with nasal deformities demonstrated no direct tumour involvement. The respective deformity was solely due to secondary gravitational effects from neurofibromas of the cheek subunit. Primary tumour infiltration of the nasal and/or labial subunits was treated with excision followed by various methods of reconstruction including lower lateral cartilage repositioning, forehead flaps, free flaps, and/or oral commissure suspension. Soft tissue deformities of the midface are very common in patients with Craniofacial Neurofibromatosis and profoundly affect overall aesthetic outcomes. Distinguishing primary from secondary involvement of the midface assists in surgical decision making.
    Journal of cranio-maxillo-facial surgery: official publication of the European Association for Cranio-Maxillo-Facial Surgery 10/2013; · 1.25 Impact Factor
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    ABSTRACT: Vomer flap repair is assumed to improve maxillary growth because of reduced scarring in growth-sensitive areas of the palate. Our aim was to evaluate whether facial growth in patients with unilateral cleft lip and palate was significantly affected by the technique of hard palate repair (vomer flap versus two-flap). For this retrospective longitudinal study, we analyzed 334 cephalometric radiographs from 95 patients with nonsyndromic complete unilateral cleft lip and palate who underwent hard palate repair by two different techniques (vomer flap versus two-flap). Clinical notes were reviewed to record treatment histories. Cephalometry was used to determine facial morphology and growth rate. The associations among facial morphology at age 20, facial growth rate, and technique of hard palate repair were assessed using generalized estimating equation analysis. The hard palate repair technique significantly influenced protrusion of the maxilla (SNA: β = -3.5°, 95 % CI = -5.2-1.7; p = 0.001) and the anteroposterior jaw relation (ANB: β = -4.2°, 95 % CI = -6.4-1.9; p = 0.001; Wits: β = -5.7 mm, 95 % CI = -9.6-1.2; p = 0.01) at age 20, and their growth rates (SNA p = 0.001, ANB p < 0.01, and Wits p = 0.02). The results suggest that in patients with unilateral cleft lip and palate, vomer flap repair has a smaller adverse effect than two-flap on growth of the maxilla. This effect on maxillary growth is on the anteroposterior development of the alveolar maxilla and is progressive with age. We now perform hard palate closure with vomer flap followed by soft palate closure using Furlow palatoplasty. These findings may improve treatment outcome by modifying the treatment protocol for patients with unilateral cleft lip and palate.
    Clinical Oral Investigations 08/2013; · 2.20 Impact Factor
  • The Laryngoscope 07/2013; · 2.03 Impact Factor
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    ABSTRACT: PURPOSE: The purposes of this study were to 1) investigate longitudinal changes in electromyographic masticatory activity subsequent to orthognathic surgery (OGS) in patients with skeletal Class III malocclusion, and 2) compare masticatory muscle activity and skeletal factors in patients with stable versus relapsed mandibular positions after OGS. MATERIALS AND METHODS: A consecutive series of patients with skeletal Class III malocclusion who underwent 2-jaw OGS (35 patients, 17 men and 18 women; age, 24.5 ± 5.0 yr) were included. Lateral cephalometric films were obtained preoperatively (T1), 1 month after OGS (T2), and at completion of orthodontic treatment (T3). Serial cephalometric tracings and analyses were obtained. Surface electromyograms of the anterior temporalis and masseter muscles were recorded at T1, T2, and T3 (6 mo after OGS). Resting tonus, maximum voluntary clench with habitual intercuspation and on cotton pads, and maximum muscle firing were evaluated. Percentage of overlapping coefficient and torque coefficient were calculated. Patients were categorized further into stable and relapse groups according to the sagittal relapse rate of mandibular setback. These surface electromyographic variables were compared between the 2 groups. RESULTS: On average, the mandible showed a significant setback of 10.19 mm and a relapse of 1.12 mm (10.99%). Surgical relapse did not correlate with gender or genioplasty. Serial surface electromyographic data indicated a significant decrease from T1 to T2 that then recovered from T2 to T3. No significant difference between T1 and T3 was noted. Percentage of overlapping coefficient was significantly decreased after OGS. The torque coefficient did not differ significantly from T1 to T3. The relapse group (relapse, >11%; n = 15) had a greater resting tonus of the anterior temporalis muscle at T3, a larger percentage of overlapping coefficient at T1, and a greater maximum voluntary clench of the masseter muscles at all times than in the stable group (n = 20). The relapse group exhibited a greater decrease in facial height (2.18 mm) from T2 to T3 than did the stable group (0.5 mm). CONCLUSION: A larger sagittal relapse of mandibular setback occurred in patients with greater masticatory muscle activity. Modifications in surgical design and overcorrection should be considered in patients with greater masticatory muscle activity before OGS.
    Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons 04/2013; · 1.58 Impact Factor
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    ABSTRACT: BACKGROUND: Interferon Regulatory Factor 6 (IRF6) is a member of the IRF family of transcription factors. It has been suggested to be an important contributor to orofacial development since mutations of the IRF6 gene has been found in Van der Woude (VWS) and popliteal pterygium syndromes (PPS), two disorders that can present with isolated cleft lip and palate. The association between IRF6 gene and cleft lip and palate has also been independently replicated in many populations. METHODS: We screened a total of 155 Taiwanese patients with cleft lip with or without cleft palate (CL/P); 31 syndromic (including 19 VWS families), 44 non-syndromic families with at least two affected members, and 80 non-syndromic patients through a combined targeted, polymerase chain reaction (PCR)-based mutation analysis for the entire coding regions of IRF6 gene. RESULTS: We found 11 mutations in 57.89% (11/19) of the VWS patients and no IRF6 mutation in 44 of the non-syndromic multiplex families and 80 non-syndromic oral cleft patients. In this IRF6 gene screening, five of these mutations (c.290 A>G, p.Tyr97Cys; c.360-375 16 bp deletion, p.Gln120HisfsX24; c.411_412 insA, p.Glu136fsX3; c.871 A>C, p.Thr291Pro; c.969 G>A, and p.Trp323X) have not been reported in the literature previously. Exon deletion was not detected in this series of IRF6 gene screening. CONCLUSIONS: Our results confirm the crucial role of IRF6 in the VWS patients and further work is needed to explore for its function in the non-syndromic oral cleft with vary clinical features.
    BMC Medical Genetics 03/2013; 14(1):37. · 2.45 Impact Factor
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    ABSTRACT: The aim of this study was to provide an overview of a single-institution, 30-year surgical experience with the soft tissue management of orbitotemporal neurofibromatosis. Lessons learned are highlighted in case presentations. From 1981 to 2011, all patients who presented to the Chang Gung Memorial Hospital Craniofacial Center with craniofacial neurofibromatosis and orbitotemporal involvement were retrospectively reviewed. The medical records of those patients who underwent surgical correction were reviewed for age, extent of involvement, procedures performed, histologic confirmation, and acute complications. All patients were grouped according to the Jackson Classification. The electronic photobank was queried to evaluate results. Thirty-five patients presented to our center with orbitotemporal neurofibromatosis during the study period. Thirty-one patients underwent surgical management of their disease. The average age was 25 years (range 4 to 57 years). Over half of our patients (n = 18) presented with concomitant disease of the cheek. The 2 most common procedures performed were lateral canthopexy (n = 24) and upper eyelid excision (n = 24). The only acute complication recorded was a postoperative hematoma on the fourth postoperative day following simultaneous lateral canthopexy and upper eyelid excision which required operative evacuation. In orbitotemporal neurofibromatosis, tissue hyperextensibility and tumor weight adversely affect outcomes. Treatment of concomitant disease of the cheek should be prioritized in order to provide periorbital support prior to addressing the delicate structures of the eyelids. Preservation of the lateral canthal unit and levator muscle, despite neurofibroma infiltration, is critical to maximize outcomes following debulking procedures of the eyelid and orbit.
    The Journal of craniofacial surgery 01/2013; 24(1):269-72. · 0.68 Impact Factor
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    ABSTRACT: PURPOSE: There is prominent lip asymmetry in patients with unilateral complete cleft lip and palate. Measurement of the lip on cleft and non-cleft sides provides appraisal of the lip deformity and information for planning of surgical correction. The purpose of this retrospective study is to evaluate the degree of lip deformity and to compare it with normative data. MATERIALS AND METHODS: From 1983 to 1997, data from a total of 168 patients with unilateral complete cleft lip and palate were collected. There were no other associated craniofacial anomalies in this patient group. The measurement was performed under general anaesthesia by a senior surgeon using a calliper prior to the first lip repair. Corresponding normative data were collected from 2002 to 2003 on 50 patients who had normal facial appearance prior to hernia repair. The measurements included lip height, lip width, philtrum length and vermilion thickness. Comparisons were made between the cleft side and the non-cleft side, as well as between cleft patients and norms. RESULTS: Comparisons between the cleft and the non-cleft sides revealed significantly longer lip on the non-cleft side, including lip height from alar base to Cupid's bow, lip width from Cupid's bow to commissure and the vermilion thickness. The lip measurements on the norms were longer than those on the cleft side of the lip, but were similar to the non-cleft side. CONCLUSION: A wide variety of tissue growth asymmetry is observed between the non-cleft and the cleft sides, indicating a deficiency of tissue development associated with the cleft deformity. These data can provide a fundamental basis for presurgical orthopaedic treatment, surgical planning, execution of surgery, postoperative assessment and may help to predict treatment outcome.
    Journal of Plastic Reconstructive & Aesthetic Surgery 12/2012; · 1.47 Impact Factor
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  • Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons 07/2012; · 1.58 Impact Factor
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    ABSTRACT: Retrobulbar haematoma formation is a known complication following facial trauma involving the orbits. This is an important clinical entity as it can lead to permanent vision loss if not appropriately managed in the acute setting. From 1999 to 2009, 2586 patients presented to the Chang Gung Memorial Hospital with orbital fractures. Eight patients presented with nine retrobulbar haematomas. A retrospective review of the patient's medical records was performed. Analysis of visual outcomes was performed based on the improvement degree (ID) formula. The average age of our patients is 24.5 years with the most common cause of trauma being motor vehicle (motorcycle) collisions. Visual acuity and the light reflex were abnormal in all patients. Five patients (case #1-5) demonstrated an absent relative afferent pupillary defect (RAPD). Computed tomography imaging confirmed the presence of a retrobulbar haematoma in all patients. The average follow-up was 14.5 months (range: 6-20 months). Management was divided into three cohorts: observation alone, medical therapy alone or a combined surgical and medical therapy. The best visual outcomes (ID = 82%) were achieved in the combined treatment group. The worst outcomes (ID = 42%) were in the medical therapy alone group. In review of our experience, we have found that the presence or absence of an RAPD is the most sensitive indicator of optic nerve compromise and necessity for intervention. An algorithm was also developed based on this study. Once a decision is made to intervene on a retrobulbar haematoma, both medical and surgical therapies should be instituted with a priority given to timely decompression of the orbit.
    Journal of Plastic Reconstructive & Aesthetic Surgery 06/2012; 65(10):1325-30. · 1.47 Impact Factor
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    ABSTRACT: . The aim of this study was to evaluate the position and dimensions of the genial tubercle in a Taiwanese sample. Cone-beam computerized tomography (CT) records of 90 adult patients with class I or class II skeletal type were used to evaluate the position and dimensions of the genial tubercle and dimensions of the anterior mandible. Subjects were grouped by sex and skeletal type. In all groups, the genial tubercle height was close to the genial tubercle width. The distance from the inferior border of the genial tubercle to the inferior border of the mandible was greater in class II male patients than in class I female patients (P < .05). The anterior mandible in class I male patients was thicker than in class II female patients (P < .05). The variable position and dimensions of this structure among patients suggest the need for cone-beam CT before attempting genioglossus advancement to treat obstructive sleep apnea.
    Oral surgery, oral medicine, oral pathology and oral radiology. 06/2012; 113(6):e46-50.
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    ABSTRACT: The apnea-hypopnea index (AHI) is a widely accepted measure for the severity of obstructive sleep apnea (OSA). Current methods to determine AHI fail to provide anatomic information for treatment decisions. In this report, we studied three-dimensional models of upper airways acquired by computed tomographic scanning with geometric measurements and computational fluid dynamics (CFD) analysis and evaluated the correlations with AHI.Participants had CT scans of their upper airways after standard polysomnography studies. Three-dimensional surface models of upper airways were generated for cross-sectional area measurements of the choanae (ACH) and the smallest cross-sectional area (Amin). Computational fluid dynamic analysis was then performed by using this three-dimensional model. Pressure differences required to set tidal volume during inspiration (ΔPmin-INSP) and expiration (ΔPmax-EXP) and minimum negative pressure produced in the level of ACH (Pmin-INSP at ACH) and Amin (Pmin-INSP at Amin) were calculated. Correlations of these parameters and the body mass index with AHI were analyzed. Statistical differences between groups of different AHI ranges were also compared.The pressure distribution simulated by CFD demonstrated abrupt pressure drops in Amin level, and this phenomenon was more significant in severe OSA. All parameters except ACH and Pmin-INSP at Amin significantly correlated with the AHI, and there were significant statistical differences between the OSA groups and the normal group. The results indicate that, in our study group, the geometry of pharyngeal airway and its CFD simulation correlate well with AHI. This model may be further applied for clinical evaluation.
    The Journal of craniofacial surgery 03/2012; 23(2):401-5. · 0.68 Impact Factor
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    ABSTRACT: The accepted surgical correction of Tessier no. 3 and no. 4 craniofacial clefts is the use of interdigitating skin flaps along the line of the facial cleft, which frequently results in unsightly facial scars, poor skin color match, and an unnatural facial expression. The authors report their technique of midface rotation-advancement concept to repair these craniofacial clefts. Fourteen patients who had undergone Tessier no. 3 and no. 4 cleft repair over a 35-year period (1976 to 2010) at the craniofacial center in Chang Gung Memorial Hospital were retrospectively reviewed. Five patients (group 1) were operated on using Z-plasty principles. Nine (group 2) were operated on using the rotation-advancement technique; six of them had Tessier no. 3 clefts and three had Tessier no. 4 clefts. Seven of those nine patients were primary cases; the other two had secondary or tertiary revisions. Patient photographs were reviewed to assess outcomes. Group 1 had a less overall satisfactory result in terms of scar quality, color matching, or natural facial expression. Overall, a much improved appearance with a higher satisfaction rate was demonstrated in group 2. Patients in group 2 who were surgically treated with the midface rotation advancement technique, though their medial canthus and alar base might not have been well repositioned, still had much better results. Midface rotation advancement avoided significant scarring with poor skin color matching and unnatural facial expressions. This technique is applicable to either the primary repair or secondary revision of Tessier no. 3 and no. 4 craniofacial clefts. Therapeutic, III.
    Plastic and Reconstructive Surgery 02/2012; 129(6):1337-44. · 3.33 Impact Factor
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    ABSTRACT: The aims of the present study were to delineate the characteristic patterns of 3-dimensional (3D) mandibular movement in patients with skeletal Class III malocclusion compared with normal individuals and to investigate the longitudinal changes in mandible and condylar motion after orthognathic surgery (OGS). The subjects in the present prospective study consisted of 2 groups. The OGS group included 24 patients with skeletal Class III who underwent OGS. The control group consisted of 25 patients who underwent orthodontic treatment only. The patient records included demographic data, lateral and posteroanterior cephalometric radiographs before treatment, and serial mandibular motion data. In the OGS group, the mandibular motion data were obtained before OGS (T1), 1 month after OGS (T2), and at least 6 months after OGS (T3). The differences in cephalometric measurements and mandibular movements between the 2 groups were compared. The Pearson correlation test was performed to assess the relationship between the cephalometric measurements and the mandibular movements. Serial changes in mandibular movement in the OGS group were also compared. The skeletal pattern in the OGS group demonstrated retrusive maxilla and a protrusive mandible, with a larger mandibular plane angle. For the incisal range of motion, the OGS group's maximal mouth opening was larger than the control group's by 6.9 mm. In the OGS group, the condylar range of motion in retrusion and the Bennett angle were asymmetric. Skeletal Class III patients tended to have a smaller range of condylar retrusion. At 1 month after OGS, the maximal incisal range of motion decreased from 57.23 to 25.61 mm. Other variables, including laterotrusion, movement velocity, and angle and distance of condylar movement in protrusion, reduced significantly. The Bennett angle demonstrated increased symmetry on both sides. Six months after OGS, the condylar motion in opening demonstrated improvements, but to a lesser extent than at T1. The condylar motion in retrusion recovered totally. The maximum incisal range of motion reduced slightly, but remained similar in value to that of the control group. The variables, including laterotrusion, movement velocity, and angle and distance of condylar movement in protrusion, demonstrated total recovery. The mandibular movement variables at T3 were not significantly different from those of the control group. Skeletal Class III patients demonstrated a larger maximal mouth opening than did the controls, along with similar laterotrusion, but with a smaller retrusive condylar range of movement. The range of incisor motion and condylar movement did not correlate. The deterioration in mandibular motion after OGS can recover totally within 6 months. At T3, the mandibular movement remained consistent with the amount in normal subjects.
    Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons 02/2012; 70(2):e158-68. · 1.58 Impact Factor

Publication Stats

906 Citations
167.21 Total Impact Points


  • 2002–2014
    • Chang Gung Memorial Hospital
      • • Craniofacial Center
      • • Division of Plastic and Reconstructive Surgery
      • • Division of Craniofacial Dentistry
      T’ai-pei, Taipei, Taiwan
  • 2002–2010
    • Chang Gung University
      • • College of Medicine
      • • Department and Graduate Institute of Mechanical Engineering
      Taoyuan, Taiwan, Taiwan
  • 2005–2008
    • Singapore General Hospital
      • Department of Plastic Surgery
      Tumasik, Singapore
  • 2007
    • National Taiwan University
      • Department of Psychology
      Taipei, Taipei, Taiwan
  • 2004
    • Kaohsiung Armed Forces General Hospital
      Kao-hsiung-shih, Kaohsiung, Taiwan