The effect of surgically assisted rapid maxillary expansion on sleep architecture: an exploratory risk study in healthy young adults

Maxillary transverse deficiencies (MTD) cause malocclusions. Rapid maxillary expansion treatment is commonly used treatment for correcting such deficiencies and has been found to be effective in improving respiration and sleep architecture in children with obstructive sleep apnoea (OSA). However, thus far, the effect of surgically assisted rapid maxillary expansion (SARME) treatment on sleep architecture and breathing of normal subjects has not been assessed. We hypothesised that sleep quality will improve after maxillary expansion treatment. The objective of this study is to access the effect of maxillary expansion treatment on sleep structure and respiratory functions in healthy young adults with severe MTD. This is a prospective and exploratory clinical study. Twenty‐eight consecutive young adult patients (15 males and 13 females, mean age 20·6 ± 5·8 years) presenting with severe MTD at the orthodontic examination were recruited into the study. All the participants underwent a standardised SARME procedure (mean expansion 6·5 ± 1·8 and 8·2 ± 1·8 mm, intercanine and intermolar distance, respectively) to correct malocclusion caused by MTD. An overnight in‐laboratory polysomnography, before and after the treatment, was performed. The mean follow‐up time was 9 months. The main outcome parameters were the changes in sleep architecture, including sleep stages, arousals, slow‐wave activity (SWA) and respiratory variables. Before surgery, young adult patients with MTD presented no evidence of sleep breathing problems. At baseline sleep recording, 7 of 28 (25%) had apnoea‐hypopnoea index (AHI) ≥ 5 events per hour. No negative effect of the SARME was observed in questionnaires or sleep laboratory parameters. In the patients with a higher baseline AHI (AHI ≥ 5 h of sleep), we observed a reduction in AHI after surgical treatment (P = 0·028). SARME did not have a negative effect on any sleep or respiration parameters in healthy young individuals with MTD. It normalised the breathing index in the patients with a mild AHI index.     

Evaluation of the effects of rapid maxillary expansion in growing children using computer tomography scanning: a pilot study

The principle of rapid maxillary expansion (RME) as a method to expand the transverse dimension of the palate and maxillary dental arch is by no means new, and previous studies have reported the effects of the method using a variety of radiographic methods. In the present study, the effect of a Hyrax splint appliance was studied in a group of nine growing children (six females, three males; mean age 8 years 1 month) undergoing orthodontic treatment. The changes were evaluated on pre- and post-treatment computer tomographic scans taken using a low-dosage protocol. The results demonstrated a clear appliance-induced effect in all patients, although the relative contribution of dental, alveolar, and skeletal changes varied from subject to subject. The average expansion, measured at the molar crowns, was 3.6 mm, whereas the actual sutural opening, the main aim of RME, was as low as 1.6 mm. The findings of this study raise doubts as to the efficiency of the Hyrax appliance and further comparative studies are recommended to evaluate other methods of maxillary expansion.     

Surgically assisted rapid maxillary expansion: a retrospective study

Transverse maxillary hypoplasia, in adolescents and adults, may be corrected by means of a 'surgically assisted rapid maxillary expansion' (SARME). The results of 7 patients who were treated by means of a SARME, are presented. Attention is paid to the technique, the type of expansion, and the stability of the expansion of the maxilla 1-1.5 years after SARME. The mean expansion between the cuspids was 4.7 mm (sd 1.7) and between the first molars 5.6 mm (sd 3.2). The SARME technique appeared to give rise to a predictable result and a sufficient amount of expansion, although the sample is small and the follow-up period relatively short. All patients had a satisfactory result without complications.     

Effect of rapid maxillary expansion on respiratory problems: 10-year retrospective study

Rhinomanometric studies have demonstrated that the maxillary fast expantion (ERM) reduces the nasal resistance of the air conduct and thus achieving the normal limits, in must cases. The hypotesis is that breathing will change from buccal to nasal, concluding that the nasal defense mechanisms (filtration, humidification and warming of inhaled air) will reduce some respiratory pathologies.     

Effect of rapid maxillary expansion on nocturnal enuresis

One of the effects of rapid maxillary expansion (RME) is a reduction in nighttime bed-wetting. The aim of this prospective study was to investigate the effects of RME on nocturnal enuresis (NE) in children who are liable to psychosocial stress conditions. Eight children (six boys and two girls) who had not responded to different conventional medical treatments were included in the study. The subjects were between eight and 11 years of age with a mean age of nine years five months, and were residents of a government orphanage. All the children wet the bed at least one time every night and previously had been subjected to unsuccessful conventional treatment modalities. Maxillary expansion was performed using a rigid acrylic RME device. Lateral and PA cephalometric films and dental casts were used in the assessment of the dentofacial and nasopharyngeal structures. Data were analyzed using a paired t-test. In seven of the eight children, remarkable improvement was observed in NE after three to six mm RME. At the end of eight months observation, the mean rate of improvement in bed-wetting in the seven successful subjects was 74.2% (57.6-87.5%). The findings also indicated significant changes in the nasomaxillary structures and nasopharyngeal airway dimensions with the use of RME. However, none of the subjects became completely dry, and the disorder is probably multicausal including psychological emotions and tensions. This study demonstrated that RME treatment could cause relief for the enuretic children. However, the long-term success rate is still questionable.     

Effect of rapid maxillary expansion on skeletal, dental, and nasal structures: a postero-anterior cephalometric study

The purpose of this study was to compare the transverse dimensions of skeletal, dental, and nasal structures of a group of patients with maxillary narrowness before and after rapid maxillary expansion (RME) with an untreated control group using postero-anterior (PA) cephalometric radiographs. The material consisted of PA cephalograms of 25 children with a posterior crossbite (mean age 13 years 4 months), and 25 age- and sex-matched controls (mean age 13 years 11 months). Both groups consisted of 20 females and five males. Thirty-four reference points were digitized using the Dentofacial Planner software program. The 17 variables studied consisted of six skeletal, four dental, and seven intra-nasal linear measurements. Student's t-tests were used to compare the differences between the groups, and the effect of RME on skeletal, dental, and nasal structures. RME produced small, but statistically significant changes in maxillary width, upper and lower molar widths, the width between upper central incisor apices, and intra-nasal width. When compared with previous studies, the changes observed were similar for patients of a similar age group, but less than reported for a younger population. There is some evidence that the pattern of expansion produced by RME will vary depending on the age and maturity of the subject.     

Perceived pain during rapid maxillary expansion in children with different expanders:: A prospective study

ObjectivesTo evaluate and compare the intensity of pain caused by rapid maxillary expansion (RME) with two expanders: Hyrax and Haas type, in growing patients.Materials and MethodsThirty-nine patients (23 girls and 16 boys) with an average age of 9.3 years (SD = 1.39 years) were randomized into two groups and treated with Hyrax- and Haas-type expanders. In both groups, initial activation of the expander screw was one full turn on the first day followed by 2/4 of a turn two times a day (morning and night) for 7 days. Inclusion criteria were patients presenting with a posterior crossbite or maxillary atresia between 7 and 12 years old. To evaluate the intensity of pain during the active phase of the treatment, a combination of the Numerical Rating Scale and Wong-Baker Faces Pain Scale was used. Mann-Whitney test was used to compare the two treatment groups.ResultsThere was significant inverse correlation between days following insertion and pain. During the expansion period, 100% of the children reported some pain. Hyrax expander subjects reported greater pain than those treated with the Haas-type expander only on the first day. The level of pain remained greater in girls throughout treatment.ConclusionsPain was reported regardless of the type of expander and was higher in the Hyrax group only on the first day of activation.     

Rapid maxillary expansion effects on nocturnal enuresis in children: a follow-up study

OBJECTIVE: To assess the effects of 10-14 days of rapid maxillary expansion (RME) on nocturnal enuresis (NE) in children who have long-standing resistance to medical therapy and to evaluate the long-term success rate after 10 years. MATERIALS AND METHODS: Twenty-three children with NE, aged 6-15 years old (mean age = 10), who wet their bed almost every night and had never been dry were referred from pediatric specialists. Mean RME was 6.5 mm (range = 5-8), but only 7 of the 23 patients had lateral crossbites. Rhinomanometric measurements were taken before and after RME, and patients were interviewed 10 years after treatment. RESULTS: Positive effects of RME were observed in nearly 50% of the patients within 1 month of treatment: six were completely dry and five had notable improvements. Relapse in the overexpanded arches to a normal transversal occlusion was noted within 1 year. No correlation was found between success and improved airways, familial heritage, school performance, or other social factors. Younger children responded better to the treatment. Results were stable at the 10-year follow-up, and no adverse reactions were reported. CONCLUSION: Orthodontic RME is a new option for treating children with NE who are resistant to medical therapy; the treatment has no adverse side effects.     

Influence of rapid maxillary expansion on nocturnal enuresis in children:: A systematic review

ObjectivesTo evaluate the influence of rapid maxillary expansion (RME) on nocturnal enuresis (NE) in children to discuss whether RME can be indicated as an alternative treatment for NE in those patients.Materials and MethodsAn electronic search was performed in the following databases: PubMed/MEDLINE, Cochrane Library, Scopus, Science Direct, Google Scholar and LILACS. The literature review was blindly performed by two reviewers. References of each selected study were manually searched to identify articles that were not found by the electronic search. Kappa statistics were used to analyze interexaminer agreement after the selection of the articles. After reading the selected full-text articles, the studies that met the inclusion criteria were assessed qualitatively using the Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) and the Revised Cochrane risk-of-bias tool for randomized controlled trials-2 (RoB 2). The certainty level of evidence was assessed through the Grading of Recommendations, Assessment, Development and Evaluation tool. Kappa tests were used to analyze the interexaminer concordance level after the quality assessment of the studies.ResultsA total of 488 articles were found; however, after applying the inclusion and exclusion criteria, only 8 studies were selected for the systematic review. A low certainty level of evidence suggested that RME seems to promote a variable reduction in frequency or a remission of NE in children in both the short (4, 6, and 8 months) and long term (13, 36, 48, and 120 months).ConclusionsBased on currently available information, RME seems to promote an improvement in NE in children. However, the low quality of the existing evidence weakens the recommendation.     

Effect of rapid maxillary expansion on monosymptomatic primary nocturnal enuresis

Objective:To evaluate the effects of rapid maxillary expansion (RME) on nocturnal enuresis (NE) related to the nasal airway, nasal breathing, and plasma osmolality (as an indicator for antidiuretic hormone).Materials and Methods:Nineteen patients with monosymptomatic primary NE, aged 6–15 years, were treated with RME for 10–15 days. To exclude a placebo effect of the RME appliance, seven patients were first treated with a passive appliance. Computed tomography of nasal cavity, rhinomanometric, and plasma osmolality measurements were made 2–3 days before and 2–3 months after the RME period. RME effects on NE were followed for three more years.Results:Two to three months after the expansion there were significant improvements in the breathing function and a decrease in the plasma osmolality. NE decreased significantly in all patients after the RME period, and all patients showed full dryness after 3 years.Conclusions:This study demonstrates that RME causes complete dryness in all patients, with significant effects on pathophysiological mechanisms related to NE.     

上颌扩弓联合双垫矫治器治疗对牙颌畸形口呼吸儿童上气道的影响

目的: 研究牙颌畸形的口呼吸患儿行上颌扩弓联合双垫矫治器（Twin-block,TB）矫治后上气道的变化。方法: 选取12例口呼吸牙颌畸形患儿行上颌扩弓和TB矫治,拍摄治疗前、后的锥形束CT（CBCT）,使用Dolphin 11.8软件对上气道进行测量。采用SPSS 21.0软件包对治疗前、后数据进行配对样本t检验。结果: 患儿上气道各测量数据在联合治疗后总体呈增长趋势,上气道总体积增加3326.44 mm³（P<0.05）。其中,舌咽部体积增加最多,平均增加1146.20 mm³（P<0.05）。口咽部最窄横截面积及鼻咽部、腭咽部、舌咽部横截面积分别扩大33.55 mm²（P>0.05）、71.68 mm²（P<0.05）、46.23 mm²（P<0.05）和54.60 mm²（P<0.05）。鼻咽部、腭咽部、舌咽部横径（P>0.05）及矢状径（P<0.05）均增加,矢状径与横径之比亦显著增大（P<0.05）。治疗后仅口咽部最窄横截面积及鼻咽部、腭咽部、舌咽部横截面处横径的增加无统计学差异。结论: 上颌扩弓联合TB治疗可增加牙颌畸形口呼吸儿童的上气道体积,使上气道形态整体趋向卵圆形,改善口呼吸症状,帮助建立正常鼻呼吸。     

A comparison of the effects of rapid maxillary expansion and fan-type rapid maxillary expansion on dentofacial structures

The aim of this study was to evaluate and compare the sagittal, transverse, and vertical effects of rapid maxillary expansion (RME) and fan-type RME on dentofacial structures. The study group consisted of 34 patients, 14 boys and 20 girls (average age 12.5 years), selected without considering their skeletal class and sex. The fan-type RME group comprised 17 subjects, who had an anterior constricted maxilla with a normal intermolar width. The RME group comprised 17 other subjects, who had a maxillary transverse discrepancy with a posterior crossbite. The records obtained for each patient included a lateral and a frontal cephalometric film, upper plaster models, and occlusal radiograph obtained before treatment (T1), after expansion (T2), and immediately after a three-month retention period (T3). The data obtained from the evaluation of the records before and after treatment, after treatment and after retention, and before treatment and after retention were compared using paired t-test. Further comparisons between the groups were made using Student's t-test. There was significantly greater expansion in the intercanine than in the intermolar width in the fan-type RME group as compared with the RME group. Downward and forward movement of the maxilla was observed in both groups. The upper incisors were tipped palatally in the RME group, but they were tipped labially in the fan-type RME group. There was significantly greater expansion in the nasal cavity and maxillary width in the RME group as opposed to the fan-type RME group.     

Photographic assessment of nasal morphology following rapid maxillary expansion in children

Objective

The aim of the present study was to use facial analysis to determine the effects of rapid maxillary expansion (RME) on nasal morphology in children in the stages of primary and mixed dentition, with posterior cross-bite.

Material and Methods

Facial photographs (front view and profile) of 60 patients in the pre-expansion period, immediate post-expansion period and one year following rapid maxillary expansion with a Haas appliance were evaluated on 2 occasions by 3 experienced orthodontists independently, with a 2-week interval between evaluations. The examiners were instructed to assess nasal morphology and had no knowledge regarding the content of the study. Intraexaminer and interexaminer agreement (assessed using the Kappa statistic) was acceptable.

Results

From the analysis of the mode of the examiners'' findings, no alterations in nasal morphology occurred regarding the following aspects: dorsum of nose, alar base, nasal width of middle third and nasal base. Alterations were only detected in the nasolabial angle in 1.64% of the patients between the pre-expansion and immediate post-expansion photographs. In 4.92% of the patients between the immediate post-expansion period and 1 year following expansion; and in 6.56% of the patients between the pre-expansion period and one year following expansion.

Conclusion

RME performed on children in stages of primary and mixed dentition did not have any impact on nasal morphology, as assessed using facial analysis.     

上颌快速扩弓治疗儿童阻塞性睡眠呼吸暂停综合征的研究进展

阻塞性睡眠呼吸暂停综合征(OSAS)是一种儿童常见的气道梗阻性疾病,对生长发育及全身健康有巨大的影响.上颌骨狭窄可能导致儿童睡眠呼吸紊乱,上颌快速扩弓(RME)是临床上常用于治疗儿童上颌骨狭窄的方法.近年来,研究显示:RME在矫正上颌狭窄的同时还能有效改善鼻通气,治疗儿童OSAS.本文的目的是探究RME治疗儿童OSAS的效果及现状.     

Effect of maxillary distraction osteogenesis on velopharyngeal function: a pilot study

OBJECTIVE: The purpose of this study was to examine preoperative and postoperative changes of velopharyngeal function in cleft patients who underwent maxillary distraction osteogenesis using the Rigid External Distraction System. STUDY DESIGN: Six cleft patients followed for a minimum of 12 months after maxillary distraction were examined. Plain and contrast lateral-cephalograms were obtained preoperatively and postoperatively, and speech evaluation was performed by the same authorized speech therapist at the same time points. RESULTS: The mean distraction amount at the anterior nasal spine was 11.7 mm (range, 7.4 mm - 15.0 mm). Both the nasopharyngeal depth and velar length increased after maxillary distraction, but the need ratio (nasopharyngeal depth/velar length) also increased after distraction. Although scores for velopharyngeal closure dropped a few points after maxillary distraction, the rating for hypernasality remained unchanged in all patients but the patient whose distraction amount was 15.0 mm. CONCLUSION: These results suggest that maxillary distraction of less than 15 mm may not markedly affect velopharyngeal function in cleft patients.     

The study of rapid maxillary expansion in the laboratory animals

Forty rabbits were used to study the rapid maxillary expansion. The widths of the dental arch and the base arch were measured. The histologic changes of the palatal medius suture tissue and periodontal tissue of the anchorage teeth after various degree of rapid maxillary expansion were observed. The result indicated that the width of dental arch and base arch were increased by expansion force. The increasing width of the dental arch almost were caused by the expansion of the medius suture chiefly. The stronger the force, the more the expansion of the palatal medius sutures, but this kind of force might cause the damage of the anchorage tooth periodontal tissue and delay the repairing and remodeling response of the tissue. The medius suture tissue has stronger endurance to the heavy expansion force.     

纤维蛋白凝胶对上颌扩弓成骨矿化的影响

目的:研究原位注射纤维蛋白凝胶对SD大鼠上颌扩弓成骨矿化的影响.方法:体外实验中,将大鼠骨髓间充质细胞(rBMSCs)在不同凝血酶浓度制备的纤维蛋白凝胶环境下进行共培养,通过CCK-8、ALP染色和活性定量以及茜素红染色,检测梯度浓度凝血酶制备的纤维蛋白凝胶降解产物对rBMSCs细胞增殖和成骨分化的影响.将rBMSCs...