Maxillomandibular advancement surgery in 23 patients with obstructive sleep apnea syndrome

Twenty-three patients with obstructive sleep apnea syndrome (OSAS) documented by polysomnography underwent maxillomandibular advancement via Le Fort I, and sagittal ramus split osteotomies followed by rigid fixation with miniplates and bicortical screws. Partial turbinectomies and septal reconstruction were simultaneously performed. Pre- and post-operative cephalometric radiographs were analyzed by computer. Hyoid position and posterior airway space changes did not correlate with clinical success. The surgical success (respiratory disturbance index less than 10) with maxillomandibular advancement was 65%. The total desaturations below 90% greatly decreased. Ninety-six percent of patients were subjectively and objectively improved.     

Maxillomandibular advancement surgery for obstructive sleep apnea syndrome

BACKGROUND: Although maxillomandibular advancement, or MMA, surgery is highly successful, the indications for and staging of MMA in the treatment of obstructive sleep apnea syndrome, or OSAS, have not been settled upon. TYPES OF STUDIES REVIEWED: The author presents a retrospective review of several published case series with inclusion criteria of 20 or more patients who underwent MMA and received documented preoperative and postoperative diagnostic polysomnography. Protocols of MMA as a primary vs. secondary operation, with and without adjunctive procedures in a site-specific approach, are compared and discussed. RESULTS: As an extrapharyngeal operation that enlarges and stabilizes the entire veloorohypopharyngeal airway, MMA, which can be safely combined with adjunctive non-pharyngeal procedures, may circumvent the staging dilemmas associated with multiple, less successful, segmental, invasive, pharyngeal procedures. In accordance with current goals and guidelines governing OSAS surgery, MMA does not need to be limited to severe OSAS cases as a last resort after other procedures have failed but, rather, is also indicated as an initial operation for (velo-oro)hypopharyngeal narrowing. CONCLUSIONS: MMA is a highly successful and potentially definitive primary single-staged surgery that may result in a significant reduction in OSAS-related health risks, as well as financial savings for the health care system. CLINICAL IMPLICATIONS: The diagnosis and management of OSAS requires a multidisciplinary team approach, including a working relationship between the dentist and sleep physician. General dentists and dental specialists who participate in the management of snoring and OSAS cases should have some knowledge of basic sleep medicine.     

下颌前伸矫治器治疗睡眠呼吸暂停综合征的三维影像学评估

目的:研究下颌前伸矫治器对阻塞性睡眠呼吸暂停综合征(OSAS)患者的疗效及机制.方法:采集80例OSAS患者应用下颌前伸矫治器治疗前、后的CT数据,利用三维影像重建技术测量上气道结构及容积变化,评价口腔矫治器(0A)的疗效及机制,采用SPSS17.0软件包对数据进行方差分析.结果:下颌前伸矫治器治疗OSAS多数患者主观症状缓解或消失,客观检测指标相应改善.OSAS患者存在上呼吸道的解剖性狭窄,戴入OA后,气道各分段截面积和容积均有变化,腭咽、喉咽段增大(P＜0.01),口咽段减小(P＜0.05).结论:OSAS存在形态学病因机制,下颌前伸矫治器通过前伸下颌骨,使上气道减小,内部变化而更平滑稳定,减小涡流和狭窄,进而发挥治疗效果.     

Three-dimensional changes in upper airways of patients with obstructive sleep apnea following maxillomandibular advancement.

PURPOSE: The purpose of this study was to analyze the morphologic changes of the airway in obstructive sleep apnea (OSA) patients by helical computed tomography (CT) scanning following maxillomandibular advancement (MMA) surgery. MATERIALS AND METHODS: Twenty consecutive OSA patients treated with MMA from 2000 to 2003 at the University of Alabama at Birmingham Hospital and diagnosed by polysomnography (PSG) were included in this study. The criteria for this study were MMA surgery, pre- and postoperative helical CT scan, and PSG. Lateral (LAT) and anterioposterior (AP) airway dimensions were measured from the level of the hard palate to the hyoid using helical CT scans. RESULTS: There was enlargement of LAT and AP diameters for all patients at all levels. LAT dimensions were enhanced greater than AP in the retroglossal region. CONCLUSION: MMA results in significant increase in both AP and LAT airway dimensions.     

Central and mixed sleep apnea related to patients treated with maxillomandibular advancement for obstructive sleep apnea: A retrospective cohort study

The aim of this study was to evaluate the clinical efficacy of maxillomandibular advancement (MMA) for obstructive sleep apnea (OSA) patients with a percentage of central and mixed apnea index in the total apnea?hypopnea index (CMAI%) ≧25%.Patients treated with MMA for OSA were retrospectively evaluated for baseline and postoperative patient data and polysomnographic results. The pre- and postoperative obstructive, central and mixed apnea parameters were compared.Of the included 78 patients, 21 patients (27%) presented with CMAI% ≧25% (median CMAI%, 49.1%; 35.9–63.8) prior to MMA. In 67% of these cases, MMA resulted in CMAI% <25 (median CMAI%, 6.1%; 2.1–8.9) and significantly improved the apnea?hypopnea index (AHI) (p < 0.001), the lowest oxyhemoglobin saturation (p < 0.001), central and mixed apnea index (p < 0.001), percentage of central and mixed apneas of total AHI (p = 0.004), central apnea index (p < 0.001), and mixed apnea index (p < 0.001). CMAI% ≧25% emerged in 25% of patients after MMA (median CMAI%, 49.1%; 35.9–63.8).Within the undeniable limitations of the study, it seems that the presence of CMAI% ≧25% should not be regarded as a contraindication for MMA in OSA patients.     

Cephalometric analysis of permanently snoring patients with and without obstructive sleep apnea syndrome

Habitual heavy snoring may be considered a preliminary stage of sleep apnea syndrome. This investigation deals with the craniofacial morphology of 51 heavily snoring patients, with and without obstructive sleep apnea, and with 28 healthy control patients. The apnea group showed a reduced posterior airway and a posterior rotation of the mandible. Reduction of the anterior-posterior diameter of the cranial base, maxilla and mandible and vertical reduction of the posterior facial height appeared to be common facial characteristics in both snoring and apnea patients. These findings indicate an anatomical disposition for snoring and apnea.     

Occlusal side effects caused by a mandibular advancement appliance in patients with obstructive sleep apnea.

Mandibular advancement appliances (MAA) have been established as an alternative treatment option for obstructive sleep apnea (OSA). Although the therapeutic effect of these devices has been proven both clinically and polysomnographically through various studies, there are very few follow-up examinations in existence concerning possible dental side effects caused by the MAA. However, if lifelong treatment of OSA is considered, these follow-up examinations are of utmost importance. This article presents 2 cases with unexpected dental side effects and occlusal alterations caused by MAA therapy.     

Long-term dentofacial changes in Chinese obstructive sleep apnea patients after treatment with a mandibular advancement device

The objective of this study was to evaluate long-term dentofacial changes in Chinese obstructive sleep apnea (OSA) patients treated with a mandibular advancement device (MAD). Lateral cephalograms in natural head posture were obtained from 67 consecutive OSA patients (mean age = 46.9 +/- 8.9 years) treated with an MAD. The cephalograms were obtained at start of treatment (T0), after 1 year (T1), 2 years (T2), and 3 years (T3) of treatment. The lateral cephalograms were digitized twice, and the average of two readings was used for statistical analyses. Small, but statistically significant changes occurred in some dentofacial variables. The lower anterior facial height steadily increased during the observation period, and this increase was significant for the T0-T1 and T1-T2 periods and marginally significant for the T2-T3 period. A significant increase in the mandibular plane angle was observed during the T0-T1 and T2-T3 periods only. Significant reductions in the overjet and overbite were observed for the T0-T1 period but not thereafter. Statistically significant dentofacial changes were observed in this study, but they were of small magnitude. The overjet and overbite changes observed mainly occurred at the initial stage of treatment.     

下颌前移矫正器治疗阻塞性睡眠呼吸暂停综合征患者的疗效分析

目的　分析下颌前移矫正器治疗阻塞性睡眠呼吸暂停综合征 (OSAS)的临床疗效及与颅面结构、上气道的关系。方法　对 4 0例轻、中度OSAS患者进行治疗前X线头影测量 ,睡眠时戴用下颌前移矫正器治疗 ,用多导睡眠图监测评价疗效 ,并与颅面结构、上气道各指标进行相关分析。结果　下颌前移矫正器治疗OSAS患者的客观有效率为 88.6 %。治疗前、后睡眠呼吸暂停的通气指数 (AHI)减少百分比 (△AHI)与颅面结构中的SNB角 (r =- 0 4 97) ,ANB角 (r=0 .5 36 )及下颌平面角MP -FH(r=- 0 2 5 2 )相关 ,亦与舌骨高度H -MP(r=- 0 35 1)及软腭的长度SPL(r=- 0 36 6 )相关。结论　下颌前移矫正器通过前移下颌间接扩大上气道达到治疗效果     

Soft tissue changes of the upper lip associated with maxillary advancement in obstructive sleep apnea patients.

PURPOSE: This retrospective study evaluated the horizontal and vertical soft tissue changes that occur with maxillary advancement surgery with a Le Fort I osteotomy with concomitant anatomic reorientation of the nasolabial musculature. SUBJECTS AND METHODS: Fifteen OSA patients who underwent maxillary advancement with a Le Fort I osteotomy without adjunctive nasal soft tissue procedures were studied after a minimum of 8 months of follow-up. The V-Y technique was used to close the maxillary vestibular incision. Only cases with minimal vertical movement (< 3.5 mm) in which no orthodontics were used were included. The average maxillary advancement was 8.0 +/- 2.5 mm, measured at the upper incisor (UPI) and the average vertical movement was 0.7 +/- 1.8 mm. The horizontal and vertical soft tissue change in subnasale (SN), labrale superiorus (LS), superior stomion (SS), nasal tip (NT), nasolabial angle (NLA), and lip length were measured in each patient and correlated with hard tissue measurements at anterior nasal spine (ANS) and UPI. The effect of lip thickness on these soft tissue changes also was evaluated. RESULTS: Using mean data, the horizontal soft-to-hard-tissue ratio for LS to UPI was 0.80:1, with a concomitant vertical (superior) soft tissue change to hard tissue advancement of 0.16:1. Lip length did not change significantly. All patients except 1 showed a slight decrease in nasolabial angle. The average decrease was 5 (range, -10 to +7 ). There was no statistically significant correlation between the degree of change in NLA and the amount of maxillary advancement. CONCLUSION: This study showed that advancement of the maxilla when controlling vertical movement resulted in the a hard-to-soft-tissue ratio of LS:UPI of 0.80:1. NLA did not change significantly.     

Skeletal advancement for the treatment of obstructive sleep apnea in children.

OBJECTIVE: Maxillomandibular advancement is curative for some adult patients with obstructive sleep apnea (OSA). Little is known, however, about the efficacy of this treatment in children. The purpose of this retrospective analysis is to assess the clinical outcomes of children with medically refractory OSA who were treated with a variety of procedures to advance the maxillofacial skeleton. METHODS: The records of eight children with OSA (five boys and three girls; mean age, 8.6 years; range, 2 to 17 years) were reviewed. Six children had identifiable syndromes associated with micrognathia, one child had mandibular ankylosis, and one child was nonsyndromic. In five of the children, conventional medical and surgical treatment of OSA had failed; therefore, these children were considered tracheostomy candidates. The remaining three children had had tracheostomies placed in infancy. Specific signs and symptoms with regard to each patient's OSA were identified and recorded. Bronchoscopy was performed preoperatively to evaluate the airway and localize the site of obstruction and again postoperatively if the patient's signs and symptoms recurred. Oxygen saturation and sleep patterns were monitored overnight in the five patients without tracheostomies, revealing a mean apnea index of 25.3 (range, 2.0 to 60.0) and mean lowest desaturation of 73% (range, 62% to 77%). All patients underwent a variety of skeletal procedures to advance the mandible, maxilla, and/or chin. OUTCOME MEASURES: Criteria for success after treatment were twofold: (1) decannulation and (2) cessation or improvement in symptoms facilitating avoidance of tracheostomy. Criteria for failure, likewise, were (1) inability to decannulate and (2) recurrence or nonimprovement in symptoms necessitating tracheostomy. RESULTS: To date, with a mean follow-up time of 7.2 years (range, 19 months to 19 years), the treatment of four of the eight children in our population can be considered a success. Two of the three children with previously placed tracheostomies were able to be decannulated within days of surgery and experienced no further signs or symptoms of OSA. Two other children experienced complete cessation of clinical signs and symptoms and elimination of previous oxygen requirements. Of the four patients in whom treatment failed, three had transient improvement (mean, 6 months) and, despite skeletal stability, eventually experienced relapse of symptoms: one patient with Down syndrome and tracheobronchomalacia required subsequent tracheostomy; the second had a central obstructive component and underwent a ventriculoperitoneal shunt for treatment of a Chiara I malformation; and the third experienced relapse of symptoms due to lack of mandibular growth. The fourth child could not be decannulated because of accompanying tracheal and laryngeal malacia. CONCLUSIONS: Skeletal advancement can be an effective treatment for medically refractory OSA in children. Success, however, is dependent not only on skeletal position but also on neuromuscular adaptation. Bronchoscopy is the most valuable diagnostic and predictive tool.