971 resultados para Mandibular advancement
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The purpose of this Study was to evaluate Soft tissue response to rnaxillo-mandibular counter-clockwise rotation, with TMJ reconstruction and mandibular advancement using TMJ Concepts (R) total joint prostheses, and maxillary osteotomies in 44 females. All patients were operated at Baylor University Medical Center, Dallas TX, USA, by one Surgeon (Wolford). Eighteen patients had genioplasties with either porous block hydroxyapatite or hard tissue replacement implants (Group 2) 26 had no genioplasty (Group 1). Surgically, the maxilla moved forward and upward by counter-clockwise maxillo-mandibular rotation with greater horizontal movement in Group 2. Vertically, both groups showed diversity of maxillo-mandibular mean movement. Group I showed a consistent 1:0.97 ratio of hard to soft tissue advancement at pogonion; Group 2 results were less consistent, with ratios between 1:0.84 and 1:1.02. Horizontal changes in upper lip morphology after maxillary advancement/impaction, VY closure, and alar base cinch sutures showed greater movement in both groups, than observed in hard tissue. Counter-clockwise rotation of the maxillo-mandibular complex using TMJ Concepts total joint prostheses resulted in similar soft tissue response as previously reported for traditional maxillo-mandibular advancement without counter-clockwise rotation of the occlusal plane. The association of chin implants, in the present sample, showed higher variability of soft tissue response.
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47 end-stage TMJ patients with high occlusal plane angulation, treated with TMJ custom-fitted total joint prostheses and simultaneous maxillo-mandibular counter-clockwise rotation were evaluated for pain and dysfunction presurgery (T1) and at the longest follow-up (T2). Patients subjectively rated their facial pain/headache, TMJ pain, jaw function, diet and disability. Objective functional changes were determined by measuring maximum interincisal opening (MIO) and laterotrusive movements. Patients were divided according to the number of previous failed TMJ surgeries: Group 1 (0-1), Group 2 (2 or more). Significant subjective pain and dysfunction improvements (37-52%) were observed (<0.001). MIO increased 14% but lateral excursion decreased 60%. The groups presented similar absolute changes, but Group 2 showed more dysfunction at T1 and T2. For patients who did not receive fat grafts around the prostheses and had previous failure of proplast/teflon and or silastic TMJ implants, more than half required surgery for TMJ debridement and removal of foreign body giant cell reaction and heterotopic bone formation. End-stage TMJ patients can be treated in one operation with TMJ custom-made total joint prostheses and maxillo-mandibular counter-clockwise rotation, for correction of dentofacial deformity and improvement in pain and TMJ dysfunction; Group 1 patients had better results than Group 2 patients.
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The purpose of this study was to evaluate the anatomical changes and stability of the oropharyngeal airway and head Posture following TMJ reconstruction and mandibular advancement with TMJ Concepts custom-made total joint prostheses and maxillary osteotomies with counter-clockwise rotation of the maxillo-mandibular complex. All patients were operated at Baylor University Medical Center, Dallas TX, USA, by one surgeon (Wolford). The lateral cephalograms of 47 patients were analyzed to determine surgical and post-surgical changes of the oropharyngeal airway, hyoid bone and head posture. Surgery increased the narrowest retroglossal airway space 4.9 mm. Head Posture showed flexure immediately after surgery (-5.6 +/- 6.7 degrees) and extension long-term post surgery (1.8 +/- 6.7 degrees); cervical curvature showed no significant change. Surgery increased the distances between the third cervical vertebrae and the menton 11.7 +/- 9.1 mm and the third cervical vertebrae and hyoid 3.2 +/- 3.9 mm, and remained stable. The distance from the hyoid to the mandibular plane decreased during surgery (-3.8 +/- 5.8 mm) and after surgery (-2.5 +/- 5.2 mm), Maxillo-mandibular advancement with counter-clockwise rotation and TMJ reconstruction with total joint prostheses produced immediate increase in oropharyngeal airway dimension, which was influenced by long-term changes in head posture but remained stable over the follow-up period.
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INTRODUCTION: Among the sleep disorders reported by the American Academy of Sleep, the most common is obstructive sleep apnea-hypopnea syndrome (OSAHS), which is caused by difficulties in air passage and complete interruption of air flow in the airway. This syndrome is associated with increased morbidity and mortality in apneic individuals. OBJECTIVE: It was the objective of this paper to evaluate a removable mandibular advancement device as it provides a noninvasive, straightforward treatment readily accepted by patients. METHODS: In this study, 15 patients without temporomandibular disorders (TMD) and with excessive daytime sleepiness or snoring were evaluated. Data were collected by means of: Polysomnography before and after placement of an intraoral appliance, analysis of TMD signs and symptoms using a patient history questionnaire, muscle and TMJ palpation. RESULTS: After treatment, the statistical analysis (t-test, and the before and after test) showed a mean reduction of 77.6% (p=0.001) in the apnea-hypopnea index, an increase in lowest oxyhemoglobin saturation (p=0.05), decrease in desaturation (p=0.05), decrease in micro-awakenings or EEG arousals (p=0.05) and highly significant improvement in daytime sleepiness (p=0.005), measured by the Epworth Sleepiness Scale. No TMD appeared during the monitoring period. CONCLUSION: The oral device developed in this study was considered effective for mild to moderate OSAHS.
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Purpose: This study evaluated oropharyngeal airway changes and stability following surgical counter-clockwise rotation and advancement of the maxillo-mandibular complex.Methods and Patients: Fifty-six adults (48 females, 8 males), between 15 and 51 years of age, were treated with Le Fort I osteotomies and bilateral mandibular ramus sagittal split osteotomies to advance the maxillo-mandibular complex with a counter-clockwise rotation. The average postsurgical follow-up was 34 months. Each patient's lateral cephalograms were traced, digitized twice, and averaged to estimate Surgical changes (T2-T1) and Postsurgical changes (T3-T2).Results: During surgery, the occlusal plane angle decreased significantly (8.6 +/- 5.8 degrees) and the maxillo-mandibular complex advanced and rotated counter-clock-wise. The maxilla moved forward (2.4 +/- 2.7 mm) at ANS and the mandible was advanced 13.1 +/- 5.1 min at menton, 10 +/- 4.4 mm at point B, and 6.9 +/- 3.7 mm at lower incisor edge. Postsurgical hard tissue changes were not statistically significant. While the upper oropharyngeal airway decreased significantly (4.2 +/- 3.4 min) immediately after surgery, the narrowest retropalatal, lowest retropalatal airway, and the narrowest retroglossal airway measurements increased 2.9 +/- 2.7, 3.7 +/- 3.2, and 4.4 +/- 4.4 mm, respectively. Over the average 34 months Postsurgical period, upper retropalatal airway increased 3.9 +/- 3.7 mm, while narrowest retropalatal, lowest retropalatal airway, and narrowest retroglossal airway remained stable. Head posture showed flexure immediately after Surgery (4.8 +/- 5.9 degrees) and extension postsurgically (1.6 +/- 5.6 degrees).Conclusion: Maxillo-mandibular advancement with counter-clockwise rotation produces immediate increases in middle and lower oropharyngeal airway dimensions, which were constrained by changes in head posture but remain stable over the postsurgical period. The upper oropharyngeal airway space increased only on the longest follow-up. (C) 2006 American Association of Oral and Maxillofacial Surgeons.
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The treatment of Class II adult individuals with mandibular deficiency has been the combination of orthodontic treatment and orthognathic surgery. Therefore, a study was conducted in which cephalometric analysis was used to evaluate the influence of dentoalveolar decompensation in Class II patients submitted to orthodontic and surgical treatment for mandibular advancement, by bilateral osteotomy of the mandibular ramus. A sample of 15 leukoderma adult female patients were selected and three cephalometric radiographs of each patient, taken before the orthodontic treatment, before surgery and after at least 6 months postoperatively, were analyzed in a total of 45 roentgenograms. The tracings were made by the manual method and the points were digitalized using software. The results showed that values of SNB increased from 75.6 to 78.6°. The measures BNP and PGNP were reduced from -12.7 to -7.7 mm and -12.7 to -6.6 mm, respectively. For ANB there was a reduction of 3.23° (from 8.1° to 4.9°). Likewise, the values of AOBO were diminished by 6.3 mm (from 7.6 to 1.3 mm), and in the values of OJ there was a reduction of 5.7 mm (from 9 to 3.3 mm). It was concluded that the pre-surgical orthodontic treatment promoted minimal and variable dental and skeletal changes in the final result. The surgical treatment caused significant skeletal changes, especially in the measurements related to the mandible (SNB, BNP, PGNP and SNPM) or indirectly to it (ANB, AOBO and OJ).
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This study focused on three-dimensional (3D) airway space changes and stability following simultaneous maxillomandibular counterclockwise rotation, mandibular advancement, and temporomandibular joint (TMJ) reconstruction with custom-made total joint prostheses (TMJ Concepts®). Cone beam computed tomography (CBCT) scans of 30 consecutive female patients with irreversibly compromised TMJs were obtained at the following intervals: T1, presurgery; T2, immediately after surgery; and T3, at least 6 months after surgery. The CBCT volumetric datasets were analysed with Dolphin Imaging ® software to evaluate surgical and postsurgical changes to oropharyngeal airway parameters. The average changes in airway surface area (SA), volume (VOL), and minimum axial area (MAA) were, 179.50 mm2, 6302.60 mm3, and 92.23 mm2, respectively, at the longest follow-up (T3 - T1) (P ≤ 0.001). Significant correlations between the amount of mandibular advancement and counterclockwise rotation of the occlusal plane and 3D airway changes were also found (P ≤ 0.01). The results of this investigation showed a significant immediate 3D airway space increase after maxillomandibular counterclockwise rotation and mandibular advancement with TMJ Concepts total joint prostheses, which remained stable over the follow-up period. © 2013 International Association of Oral and Maxillofacial Surgeons.
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The purpose of this study was to evaluate skeletal and dental stability in patients who had temporomandibular joint (TMJ) reconstruction and mandibular counterclockwise advancement using TMJ Concepts total join, prostheses (TMJ Concepts Inc. Ventura, CA) with maxillary osteotomies being performed at the same operation. All patients were operated at Baylor University Medical Center, Dallas TX, USA, by one surgeon (Wolford). Forty-seven females were studied; the average post-surgical follow-up was 40.6 months. Lateral cephalograms were analyzed to estimate surgical and post-surgical changes. During surgery, the occlusal plane angle decreased 14.9 +/- 8.0 degrees. The maxilla moved forward and upward. The posterior nasal spine moved downward and forward. The mandible advanced 7.9 +/- 3.5 mm at the lower incisor tips, 12.4 +/- 5.4 mm at Point B, 17.3 +/- 7.0 mm at menton, 18.4 +/- 8.5 mm at pogonion, and 11.0 +/- 5.3 mm at gonion. Vertically, the lower incisors moved upward -2.9 +/- 4.0 mm. At the longest follow-up post surgery, the maxilla showed minor horizontal changes while all mandibular measurements remained stable. TMJ reconstruction and mandibular advancement with TMJ Concepts total joint prosthesis in conjunction with maxillary osteotomies for counter-clockwise rotation of the rnaxillo-mandibular complex was a stable procedure for these patients at the longest follow-up.
Resumo:
INTRODUCTION: Among the sleep disorders reported by the American Academy of Sleep, the most common is obstructive sleep apnea-hypopnea syndrome (OSAHS), which is caused by difficulties in air passage and complete interruption of air flow in the airway. This syndrome is associated with increased morbidity and mortality in apneic individuals. OBJECTIVE: It was the objective of this paper to evaluate a removable mandibular advancement device as it provides a noninvasive, straightforward treatment readily accepted by patients. METHODS: In this study, 15 patients without temporomandibular disorders (TMD) and with excessive daytime sleepiness or snoring were evaluated. Data were collected by means of: Polysomnography before and after placement of an intraoral appliance, analysis of TMD signs and symptoms using a patient history questionnaire, muscle and TMJ palpation. RESULTS: After treatment, the statistical analysis (t-test, and the "before and after" test) showed a mean reduction of 77.6% (p=0.001) in the apnea-hypopnea index, an increase in lowest oxyhemoglobin saturation (p=0.05), decrease in desaturation (p=0.05), decrease in micro-awakenings or EEG arousals (p=0.05) and highly significant improvement in daytime sleepiness (p=0.005), measured by the Epworth Sleepiness Scale. No TMD appeared during the monitoring period. CONCLUSION: The oral device developed in this study was considered effective for mild to moderate OSAHS.
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PURPOSE: The purpose of the present systematic review was to evaluate the soft tissue/hard tissue ratio in bilateral sagittal split advancement osteotomy (BSSO) with rigid internal fixation (RIF) or wire fixation (WF). MATERIALS AND METHODS: The databases PubMed, Medline, CINAHL, Web of Science, Cochrane Library, and Google Scholar Beta were searched. From the original 711 articles identified, 12 were finally included. Only 3 studies were prospective and 9 were retrospective. The postoperative follow-up ranged from 3 months to 12.7 years for RIF and 6 months to 5 years for WF. RESULTS: The short- and long-term ratios for the lower lip to lower incisor for BSSO with RIF or WF were 50%. No difference between the short- and long-term ratios for the mentolabial-fold to point B and soft tissue pogonion to pogonion could be observed. It was a 1:1 ratio. One exception was seen for the long-term results of the soft tissue pogonion to pogonion in BSSO with RIF; they tended to be greater than a 1:1 ratio. The upper lip mainly showed retrusion but with high variability. CONCLUSIONS: Despite a large number of studies on the short- and long-term effects of mandibular advancement by BSSO, the results of the present systematic review have shown that evidence-based conclusions on soft tissue changes are still unknown. This is mostly because of the inherent problems of retrospective studies, inferior study designs, and the lack of standardized outcome measures. Well-designed prospective studies with sufficient sample sizes that have excluded patients undergoing additional surgery (ie, genioplasty or maxillary surgery) are needed.
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This study analyzes short- and long-term skeletal relapse after mandibular advancement surgery and determines its contributing factors. Thirty-two consecutive patients were treated for skeletal Class II malocclusion during the period between 1986 and 1989. They all had combined orthodontic and surgical treatment with BSSO and rigid fixation excluding other surgery. Of these, 15 patients (47%) were available for a long-term cephalography in 2000. The measurement was performed based on the serial cephalograms taken preoperatively; 1 week, 6 months and 14 months postoperatively; and at the final evaluation after an average of 12 years. Mean mandibular advancement was 4.1 mm at B-point and 4.9 mm at pogonion. Representing surgical mandibular ramus displacement, gonion moved downwards 2 mm immediately after surgery. During the short-term postoperative period, mandibular corpus length decreased only 0.5 mm, indicating that there was no osteotomy slippage. After the first year of observation, skeletal relapse was 1.3 mm at B-point and pogonion. The relapse continued, reaching a total of 2.3 mm after 12 years, corresponding to 50% of the mandibular advancement. Mandibular ramus length continuously decreased 1 mm during the same observation period, indicating progressive condylar resorption. No significant relationship between the amount of initial surgical advancement and skeletal relapse was found. Preoperative high mandibulo-nasal plane (ML-NL) angle appears to be associated with long-term skeletal relapse.
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PURPOSE: The aim of this study was to assess long-term changes in position of soft tissue landmarks following mandibular advancement and setback surgery. MATERIALS AND METHODS: Twenty-seven patients (14 women, 13 men; mean age, 36 years) who had undergone either mandibular advancement (15 patients) or setback surgery (12 patients), were available for a long-term follow-up an average of 12 years postoperatively. In all of these cases, lateral cephalometric radiographs taken immediately before operation, at 1 week, 14 months, and 12 years postoperatively, were studied. RESULTS: During the 14 months postoperatively, soft tissue chin and mentolabial fold followed its underlying hard tissue in all patients. A continuous skeletal relapse was observable 12 years after mandibular advancement, but soft tissue chin moved more in an anterior direction. After mandibular setback, soft and hard tissue landmarks remained almost unchanged. Over the entire observation period, a thickening of soft tissue at pogonion was generally seen, and particularly a thickening of the whole chin in the setback group. All patients showed a significant lengthening and thinning of the upper lip. In all except 2 males, the patient's body weight increased markedly. CONCLUSION: In contrast to the immediate postoperative stage, soft tissue changes observed an average of 12 years after the primary operation do not directly follow the movements of the underlying skeletal structure. The soft tissue profile changes observed over such a long term seem to be influenced not only by the underlying skeletal structure but also by other factors such as weight gain and aging process.
Resumo:
The aim of the study was to conduct a long-term follow-up investigation of the stability of hard and soft tissues after bilateral sagittal split osteotomy (BSSO) with rigid internal (RIF) fixation to advance the mandible. Sixteen consecutive patients (12 females and 4 males, mean age 21.4 years) were available for re-examination 12.7 years (T5) after surgery. The preceding follow-ups were before (T1), and 5 days (T2), 7.3 months (T3), and 13.9 months (T4) after surgery. Lateral cephalograms were traced by hand, digitized, and evaluated with the Dentofacial Planner program. The x-axis for the system of co-ordinates ran through sella (point zero) and the line NSL -7 degrees. Thus, the program determined the x- and y-values of each variable and the usual angles and distances. Statistical analysis was carried out using Wilcoxon's matched-pair signed-ranks test with Bonferroni adjustments. The relationships between the examined variables were analysed by Spearman rank correlation coefficients. The backward relapse at point B (T5) was 2.42 mm, or 50 per cent, and at pogonion 3.21 mm, or 60 per cent of the initial advancement. The mean net effect at T5 on the labial fold (soft tissue point B) was 94 per cent of the advancement at point B. For the soft tissue chin (soft tissue pogonion), it was 119 per cent of the advancement at pogonion. The net effect on the lower lip (labrale inferior) was 55 per cent of the advancement at incision inferior. The amount of the surgical advancement of the mandible was correlated with the long-term relapse in point B. Among possible reasons for this relapse are the initial soft tissue profile, the initial growth direction, and the remodelling processes of the hard tissue.
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BACKGROUND: General anesthesia in adult humans is associated with narrowing or complete closure of the pharyngeal airway. The purpose of this study was to determine the effect of progressive mandibular advancement on pharyngeal airway size in normal adults during intravenous infusion of propofol for anesthesia. METHODS: Magnetic resonance imaging was performed in nine normal adults during wakefulness and during propofol anesthesia. A commercially available intraoral appliance was used to manually advance the mandible. Images were obtained during wakefulness without the appliance and during anesthesia with the participants wearing the appliance under three conditions: without mandibular advancement, advancement to 50% maximum voluntary advancement, and maximum advancement. Using computer software, airway area and maximum anteroposterior and lateral airway diameters were measured on the axial images at the level of the soft palate, uvula, tip of the epiglottis, and base of the epiglottis. RESULTS: Airway area across all four airway levels decreased during anesthesia without mandibular advancement compared with airway area during wakefulness (P < 0.007). Across all levels, airway area at 50% advancement during anesthesia was less than that at centric occlusion during wakefulness (P = 0.06), but airway area with maximum advancement during anesthesia was similar to that during wakefulness (P = 0.64). In general, anteroposterior and lateral airway diameters during anesthesia without mandibular advancement were decreased compared with wakefulness and were restored to their wakefulness values with 50% and/or maximal advancement. CONCLUSIONS: Maximum mandibular advancement during propofol anesthesia is required to restore the pharyngeal airway to its size during wakefulness in normal adults.