Effects Of Mandibular Distraction Osteogenesis Research Articles

3D-CT measurements of Airway Morphology in Severe CFM Patients: A comparative study between ascending ramus distraction osteogenesis and Bone Grafting

This study investigated the differential effects of mandibular distraction osteogenesis (MDO) and bone grafting on upper airway morphology in pediatric patients with Pruzansky-Kaban type IIB and III craniofacial microsomia (CFM). A retrospective analysis was performed on medical records and three-dimensional computed tomography (3D-CT) scans of CFM patients who had undergone MDO or bone grafting as primary interventions. Preoperative and postoperative imaging data were evaluated to quantify and compare changes in airway dimensions between the two surgical groups. Parameters such as airway volume, surface area, length, mean and minimum cross-sectional areas, and sphericity were measured across the nasopharynx, oropharynx, and laryngopharynx. Data normality was assessed using the Shapiro-Wilk test, and statistical comparisons were made using either paired t-tests or the Wilcoxon signed-rank test, depending on distribution characteristics. Eighteen children with type IIB and III CFM were included in the study, with 11 undergoing MDO and 7 receiving bone grafting. In the MDO group, postoperative measurements revealed significant increases in nasopharyngeal length and surface area (P=0.001, P=0.036), along with notable improvements in oropharyngeal length, volume, surface area, mean and minimum cross-sectional areas, and sphericity (P<0.05). In contrast, the bone grafting group exhibited a significant increase only in nasopharyngeal length (P=0.019), without substantial postoperative changes in other airway parameters. These findings suggested that MDO leads to more pronounced improvements in upper airway morphology, particularly in the nasopharynx and oropharynx, compared to bone grafting, which demonstrated minimal impact on airway dimensions.

3D-CT measurements of facial symmetry in severe CFM patients: A comparative study between mandibular ascending ramus distraction osteogenesis and bone grafting

This study aims to compare the effects of mandibular distraction osteogenesis (MDO) and bone grafting on the facial symmetry of children with Pruzansky-Kaban type IIB and III craniofacial microsomia (CFM).Medical records and three-dimensional computed tomography (3D-CT) data of CFM patients who had primarily undergone MDO and bone grafting were collected. A retrospective analysis of pre-and post-operative 3D imaging data was conducted to compare the improvement rate in facial symmetry between the two groups based on occlusal cant, affected/unaffected ramus height ratio and chin point deviation. The data were tested for normality using the Shapiro-Wilk test. When the data followed a normal distribution, a paired sample t-test was employed for the comparison between preoperative and postoperative data. When the data did not follow a normal distribution, the Wilcoxon signed-rank test for paired samples was used for preoperative and postoperative comparison.The study included 18 children with type IIB and III CFM, 11 in the MDO group and 7 in the bone grafting group. In the MDO group, postoperative Gn-FH and Gn-Cor distances increased significantly, whereas the postoperative Gn-Mid distance decreased significantly. Occlusal cant decreased significantly and ramus height affected/unaffected ratio increased significantly after MDO. In the bone graft group, there was no statistically significant difference in the postoperative ratios of chin deviation, occlusal cant, and ramus height affected/unaffected compared to the preoperative values.Compared to bone grafting, MDO can significantly enhance ramus height ratio, level occlusal plane, and centralize the chin point among patients with CFM. Furthermore, MDO achieves superior enhancements in facial symmetry.

Mid-term effect of mandibular distraction osteogenesis on clinical and polysomnography findings of patients with Robin sequence

The study aimed to evaluate the mid-term effect of MDO in children with Robin sequence (RS). In this case series, 13 patients with RS who underwent MDO were followed up for more than 5 years. Data were collected using clinical history and physical examination. Polysomnography was performed and endoscopic evaluations of the airway was performed if patients still presented obstructive signs of upper airways and/or dysphagia. The patients’ clinical signs improved in the mid-term after versus before MDO (inspiratory noise, 92,3% vs 30,8%; apnea, 84,6% vs 7,7%; cyanosis, 76,9% vs 0%; desaturations, 69,2% vs 0%; and suprasternal/intercostal retractions, 61,5% vs 0%; p < 0.05). Statistically significant improvement was noted in the following polysomnographic parameters evaluated in the pre and postoperative mid-term: apnea-hypopnea index, total sleep time and desaturation index (p < 0.05). Within the limitations of the study it seems that MDO is an effective surgical option for children with RS, not only in the short term as previously demonstrated, but also in the mid-term.

Respiratory outcome of mandibular distraction osteogenesis on obstructive sleep apnea in craniofacial microsomia: A retrospective study

This study aimed to evaluate the effect of mandibular distraction osteogenesis (MDO) on respiratory function in CFM patients with obstructive sleep apnea (OSA) according to polysomnography (PSG).This study retrospectively analyzed patients with CFM who underwent PSG before surgery and after completion of mandible distraction. Patients who met the inclusion criteria were selected. The Pediatric Sleep Questionnaire (PSQ) was used to assess patients' signs and symptoms related to OSA. The obstructive apnea-hypopnea index (OAHI) and lowest oxygen saturation (LSaO2) were imported into SPSS version 26.0. The Wilcoxon signed-rank test was used to assess the differences in PSG before and after MDO. Other data were described using descriptive statistics. A P-value less than 0.05 was considered statistically significant.A total of 25 unilateral CFM patients were included in this study. Most patients (72%) had mild OSA; moderate and severe OSA were 12% and 16%, respectively. Snoring (52%) was the most common symptom among these patients. After completion of mandibular distraction, snoring and other OSA-related symptoms were significantly improved. Twelve patients had normalized PSG and the severity of OSA improved significantly in 3 patients. The total effective rate of MDO for OSA was 60%. The statistical results showed that OAHI (P = 0.045) decreased and LSaO2 (P = 0.009) increased significantly compared to preoperative values.MDO can improve OSA-related symptoms in CFM patients. In addition, respiratory function was improved in most patients after MDO, based on PSG. CFM patients, especially those with OSA, can benefit from MDO.

Mandibular morphology and distraction osteogenesis vectors in patients with Robin sequence

The aims of this cohort study were to compare the mandibular morphology between patients with Robin sequence (RS) and controls, and to examine the effects of mandibular distraction osteogenesis (MDO) using different vectors. Measurements of the mandibles of 80 patients with RS and 46 controls aged< 90 days were made using computed tomography. The data were compared among isolated RS patients (n = 58), syndromic RS patients (n = 22), and controls. Patients with RS exhibited significantly shorter ramus and body lengths and larger symphyseal angles than controls (all P < 0.001). Patients with isolated RS had shorter body lengths (P < 0.001), while syndromic patients had shorter ramus and body lengths (both P < 0.001) than controls. Seventy RS patients underwent MDO. Pre-MDO (n = 37) and post-MDO (n = 29) mandibular measurements were compared between patients undergoing MDO with a vertical vector and those undergoing MDO with a horizontal vector. Polysomnography data from part of the cohort highlighted the effectiveness of both vectors. MDO with a horizontal vector conferred 11% and 36% increases in ramus and body length, respectively, while these increases were 34% and 27.5%, respectively, with a vertical vector. MDO with a vertical vector was effective in lengthening ramus and body components and should be considered in the presence of ramus hypoplasia.

Effects of mandibular distraction osteogenesis on anesthetic implications in children with hemifacial microsomia.

Hemifacial microsomia (HFM) is a congenital craniofacial malformation, and its features include hypoplasia and asymmetry in skeletal tissue and soft tissue. These features are usually associated with a difficult airway. Mandibular distraction osteogenesis can achieve mandibular advancement, but its effect on the subsequent laryngoscopic views has not been adequately documented. The aim of this study was to determine the change in laryngoscopic views after mandibular distraction osteogenesis (MDO) in children with HFM and to examine the radiological changes after MDO by using computed tomography (CT)-based three-dimensional (3-D) airway reconstruction. An observational prospective study was carried out in children with HFM undergoing MDO. All children underwent 3-D airway reconstruction preoperatively before the placement and removal of the distractor. The temporomandibular joint lesions in children were classified by the Pruzansky-Kaban classification. The Cormack-Lehane grade was assessed after induction under direct laryngoscopy. The relationship between difficult laryngoscopy and the Pruzansky-Kaban classification was assessed. Changes in the upper pharyngeal airway parameters and laryngoscopic views were analyzed. Forty children (ages ranging from 5 to 16 years, males=26, females=14) with HFM underwent 80 anesthesia for MDO. The incidence of difficult laryngoscopy before mandibular distraction was 5/12 (41.7%) in type IIa, 19/24 (79.2%) in type IIb and 1/4 (25%) in type III HFM. The mean difference in the incidence of difficult laryngoscopy before and after MDO was 33.3% (95% CI: -6.7% to 73.3%), 50.0% (95% CI: 8.4% to 91.6%), and 0% for type IIa, type IIb, and type III, respectively. In type IIb, 12/19 cases of difficult laryngoscopy became easy after mandibular distraction: this was associated with an increase in the palatopharyngeal and glossopharyngeal CT parameters (p < .05). In type IIa, 5/5 cases of difficult laryngoscopy became easy after mandibular distraction, and 1/7 cases of easy laryngoscopy became difficult laryngoscopy. However, there were no significant changes in the palatopharyngeal, glossopharyngeal, and hypopharyngeal CT parameters in type IIa and type III HFM (p>.05). MDO can improve the laryngoscopic views in children with HFM. According to the Pruzansky-Kaban classification, children with type IIb showed the highest incidence of difficult laryngoscopy before MDO. After MDO, the improvement in laryngoscopic views under direct laryngoscopy in type IIb was related to the increase in the palatopharyngeal and glossopharyngeal volume.

Pediatric Mandibular Distraction Osteogenesis and Long-Term Dental Morbidity: A Clinical Evaluation and Review of the Literature

Objectives: Pediatric mandibular distraction osteogenesis (MDO) is an increasingly common surgical procedure used to lengthen the mandible. Little is known about the long-term effects of MDO on dental development. This retrospective study sought to identify dental abnormalities at mixed dentition and early permanent dentition stages in patients who had undergone MDO. Methods: All pediatric patients who underwent MDO with imaging and clinical exams at mixed dentition and early permanent dentition stages were evaluated identify pathology. Data included demographic information, medical and surgical history, complications, and dental exam information. Descriptive statistics were reported. Results: Twenty-two hemimandibles at mixed dentition stage and 24 at early permanent stage were included. Mean age at initial MDO was 7.95 years with a mean follow-up time of 15.1 years. Nine patients required more than 1 distraction. At the mixed dentition stage, all patients showed abnormalities. The most common abnormalities were absent, dysplastic, or ectopic molars. At early permanent dentition stage, 87.5% of patients had dental abnormalities. The most common abnormality was missing molars (third, second, and first), but dysplastic, impacted, and ectopic teeth were also noted. At both mixed and early permanent dentition stages, some patients were noted to have abnormal V-shaped sigmoid notching of the mandibular ramus of undetermined clinical significance. Buccal mucosal scarring that interfered with orthodontic treatment was observed in a subset of patients. Conclusions: This study provides long-term dental analyses of patients undergoing MDO for mandibular hypoplasia. Dental abnormalities were seen at both mixed and early permanent dentition stages. Molars were the most commonly affected with absence the most commonly seen abnormality. Dysplastic, ectopic, and impacted teeth were also seen in posterior and anterior dentition, and abnormalities in buccal soft tissue and the mandibular ramus were also seen. MDO remains a crucial tool for functional and aesthetic improvement in children with hypoplastic mandibles. Dental abnormalities as a consequence of MDO should be considered as part of surgical planning process.

Effects of Mandibular Distraction Osteogenesis on Three-Dimensional Upper Airway Anatomy in Newborns Affected by Isolated Pierre Robin Sequence.

Effective airway management is critical to Pierre Robin Sequence treatment. The goal of this study is to assess the three-dimensional changes in airway size and shape in 117 newborns with isolated Pierre Robin sequence who underwent mandibular distraction osteogenesis. During the study period (11/29/2016 to 11/26/2019), 117 newborns affected by isolated Pierre Robin sequence met the inclusion criteria for the present study. All 117 included patients underwent linear distraction. Demographic variables were recorded and analyzed. Cone-beam computed tomography were performed before and after mandibular distraction osteogenesis. A systemic quantitative three-dimensional analysis of size and shape of upper airway was performed. The mean age was 71 day (range 12 to 213). The mean weight was 3.9 kg (range 2.3-6.8). A total of 53 patients are female and 64 are male. When the distraction device was removed, the upper and lower jaws were symmetrically aligned. Pre- and post-distraction comparison clearly showed osteogenesis. For the size of the upper airway, airway volume, anteroposterior dimension of the retroglossal airway, lateral dimension of retroglossal airway, minimum retropalatal area, minimum retroglossal area, average cross-sectional area and minimum cross-sectional area increased significantly after mandibular distraction osteogenesis (P < 0.001). However, the airway length did not change significantly (P > 0.05). For the shape of the upper airway, the lateral/anteroposterior ratio in the retroglossal region and the ratio of the retropalatal airway diameter to the retroglossal airway diameter significantly decreased after mandibular distraction osteogenesis (P < 0.001). The airway uniformity significantly increased after mandibular distraction osteogenesis (P < 0.001). Mandibular distraction osteogenesis for isolated Pierre Robin sequence improved size and shape of the upper airway, further confirming mandibular osteogenesis distraction as an effective surgical modality to address the airway obstruction in newborns affected by isolated Pierre Robin sequence. Cone-beam computed tomography scanning and analysis can serve as a safe and effective examination modality for upper airway applications of PRS newborns.

The Effect of Mandibular Distraction Osteogenesis on Weight Velocity in Infants With Severe Pierre Robin Syndrome.

Mandibular distraction osteogenesis (MDO) effectively improves airway obstruction in Pierre Robin syndrome (PRS) patients. However, whether or not early MDO is beneficial to the development of children is still controversial. To observe the influence of PRS patient age at the time of MDO on their development, the authors retrospectively analyzed preoperative and postoperative body weight in 41 children with PRS who underwent MDO treatment from 2014 to 2016. The body weight of the infants at the time of birth, first visit, MDO surgery, distractor removal, and palatoplasty surgery was recorded. The body weight percentile significantly fell from 34.4 ± 5.8 at birth to 13.1 ± 3.6 at the time of MDO (P < 0.001), and increased to 28.3 ± 5.3 at distractor removal (P < 0.05) following MDO, finally reaching 42.4 ± 6.5 at palatoplasty surgery (P < 0.001). The infants who accepted MDO treatment at <1 month of age maintained a significantly higher body weight percentile than those who accepted MDO surgery at 1 to 3 months or 4 to 7 months of age, at the time of both MDO and palatoplasty surgeries (P < 0.05). After the MDO procedure, the body weight percentiles of the PRS infants with a cleft palate were comparable to those without a cleft palate at the time of palatoplasty surgery. The body weight percentile quickly climbed to 74.0 ± 35.2 at the time of distractor removal, from 46.7 ± 18.2 at the time of MDO. In conclusion, early MDO was beneficial in severe cases of PRS for patients to recover body weight and to allow for earlier palatoplasty surgery.

The effect of mandibular distraction osteogenesis on airway obstruction and polysomnographic parameters in children with Robin sequence

IntroductionThe optimal surgical technique for the management of patients with Robin Sequence (RS) has not been established. One of the most commonly used surgical techniques, mandibular distraction osteogenesis (MDO), is still controversial because of its potential risks and the lack of clear evidence of its efficacy. ObjectivesTo assess variations in airway patency, clinical symptoms, and polysomnographic parameters in children with RS who underwent MDO. MethodsIn this prospective cohort study, 38 patients with RS were evaluated before and after MDO. Symptom severity was classified using a grading scale for RS clinical manifestations. Patients underwent flexible fiberoptic laryngoscopy, and the images were classified by a blinded examiner using two validated grading scales for airway obstruction. Patients not requiring ventilatory support underwent a polysomnography. ResultsPatients' symptoms significantly improved after MDO, as shown by a decreased score in the grading scale for RS clinical manifestations (preoperative score of 2.20 vs. postoperative score of 0.81; P < 0.001). The two endoscopic grading scales also showed a statistically significant postoperative improvement in airway obstruction (first scale: preoperative score of 1.56 vs. postoperative score of 0.92; second scale: preoperative score of 2.19 vs. postoperative score of 1.16; P < 0.001 for both). Moreover, there was a statistically significant variation in the following polysomnographic parameters evaluated pre- and postoperatively: apnea-hypopnea index, total sleep time, oxygen desaturation nadir, and oxygen desaturation index (P < 0.05). ConclusionsMDO seems to be an effective surgical option for children, as shown by postoperative improvements in clinical symptoms, endoscopic grading scales, and polysomnographic parameters.

The Pierre Robin Mandible is Hypoplastic and Morphologically Abnormal.

For Pierre Robin sequence (PRS) patients, there is incomplete characterization of 3D differences and effects of mandibular distraction osteogenesis (MDO) on the mandible compared to normal controls. PRS infants who underwent MDO at 2 craniofacial referral centerals with pre- and postoperative computed tomography (CT) scans were identified. A group of age-matched control patients with CTs were identified in the PACS database. Demographic and perioperative data were recorded. Mandibular lengths, angles, and volumes were measured. Morphologic and outcomes data were analyzed in a case-control comparison. Sixty-three CT scans were analyzed. Fifteen pre-op PRS patient and 15 control CTs were well matched in terms of age and sex. Mandibular volume (78%), ramus length (87%), and body length (95%) were all decreased in the PRS patients. Anterior symphyseal angle (84%) was significantly reduced in PRS patients while mandibular angle (102%) was maintained. Eighteen post-op PRS patient and 15 control CTs were well matched in terms of age and gender. Mandibular volumes (106%) were normalized following distraction with shorter mandibular rami (88%) and longer mandibular bodies (109%). Postoperatively, mandibular angle (100%) and anterior symphyseal angle (99%) were ultimately indistinguishable from controls. The mandible in PRS is dysmorphic compared to age-matched controls. Overall, they have a smaller volume, shorter ramus, and an obtuse symphyseal angle. MDO improves mandibular volume and normalizes the symphyseal angle, but results in a longer mandibular body and shorter mandibular ramus.

ウサギ舌骨上筋群に及ぼす下顎骨延長の影響(大阪歯科大学大学院歯学研究科博士(歯学)学位論文内容要旨および論文審査結果要旨の公表)

ウサギ舌骨上筋群に及ぼす下顎骨延長の影響(大阪歯科大学大学院歯学研究科博士(歯学)学位論文内容要旨および論文審査結果要旨の公表)

Effect of mandibular distraction osteogenesis and sagittal split osteotomy on the upper respiratory airway (comparative study)

Effect of mandibular distraction osteogenesis and sagittal split osteotomy on the upper respiratory airway (comparative study)

Distraction osteogenesis as a treatment of obstructive sleep apnea syndrome: A systematic review.

Background:To conduct a systematic review to answer the clinical question “What are the effectiveness of mandibular distraction osteogenesis (MDO) and its complications to treat patients with obstructive sleep apnea syndrome (OSAS)?”.Methods:A systematic search including a computer search with specific keywords, reference list search, and manual search were done. Relevant articles on MDO were assessed and selected in 3 rounds for final review based on 5 predefined inclusion criteria and followed by a round of critical appraisal. Different types of distraction and their treatment outcomes of OSAS were recorded with standardized form and analyzed.Results:Twelve articles were included in the final review. A total of 256 patients aged 7 days to 60 years were treated with either external or internal MDO, with a mean follow-up period of 6 to 37 months. The average distraction distance of 12 to 29 mm was achieved with various distraction protocols. The success rate for adult patients was 100%, and cure rates were ranged from 82% to 100%. The definition of success or cure for OSAS in children or infants was not defined. Therefore, there were no clearly reported success or cure rates for children/infants in the included studies. However, all studies reported that these patients showed significant improvement in OSAS, with many of them who avoided tracheostomy or had the tracheostomy decannulated. The complication rates were ranged from 0% to 21.4%, with most being from local wound infections or neurosensory disturbances.Conclusion:This systematic review showed that MDO was effective in resolving OSAS in adults with retrognathic mandible. MDO also showed promising results in infants or children with OSAS. From the results of this systematic review, we recommend to define the criteria of success or cure for OSAS surgery in children and infants. We also recommend setting up randomized controlled trials to compare MDO with traditional maxillomandibular advancement surgery for OSAS patients and to provide a better evidence on the success and complication rates of the techniques.

Long-Term Effects of Mandibular Distraction Osteogenesis

Distraction osteogenesis (DO) has become a reliable technique for correcting craniofacial deformities by skeletal expansion. Osteotomies and devices used for mandibular DO are often adjacent to developing or erupted teeth which can be displaced and/or damaged.1 Few studies specifically characterize the effects of mandibular DO on the dentition. In addition, controversy exists as to whether the distracted mandible continues to grow.2 The purpose of this study is to determine the effects of mandibular DO on the dentition and on subsequent mandibular growth in children.

Sleep architecture in Pierre-Robin sequence: The effect of mandibular distraction osteogenesis

IntroductionPierre-Robin Sequence (PRS), a triad of micro/retrognathia, glossoptosis, and upper airway obstruction, usually in conjunction with a cleft palate is frequently associated with significant morbidity. Mandibular distraction osteogenesis (MDO) is an effective treatment modality to address retroglossal upper airway obstruction by increasing the anterior-posterior diameter of the infant airway. Although MDO has been shown to improve the apnea-hypopnea index (AHI) in children with PRS, the consequences of MDO on other aspects of infant sleep, including hypercapnea, hypoxia, the REM to Non-REM ratio, as well as its effect on central and mixed apneas has not been investigated with an adequate sample size. ObjectiveTo characterize the effect of MDO on key components of sleep architecture in infants with PRS. MethodsCharts from 32 infants with PRS that were addressed with MDO at our tertiary-care children's hospital were retrospectively reviewed. Of these, 26 infants (57.7% male; mean age = 4.1 weeks, SD = 5.0) had pre- and post-operative polysomnograms (PSG). Paired samples t-tests were used to compare pre- and post- MDO sleep architecture mean score differences. ResultsAmong the 26 infants, 73.1% demonstrated severe pre-MDO sleep apnea (AHI > 10). Several aspects of sleep architecture were found to improve post-operatively. Significant improvements were found in AHI (30.3 vs. 8.7; t = 4.1, p < 0.001), obstructive apneas (79.3 vs. 5.8; t = 4.0, p < 0.001), hypopneas (48.1 vs. 22.1; t = 2.2, p = 0.040), time spent below 90% SpO2 (3.9% vs. 0.7%; t = 3.3, p = 0.003), and lowest SpO2 nadir (75.4% vs. 82.9%; 3.4, p = 0.002). In addition, a marginally significant improvement was found for mixed apnea (6.3 vs. 1.6; t = 1.99, p = 0.058). ConclusionMDO improves several sleep architecture parameters in this sample of infants with PRS. Statistically significant improvement was seen in obstructive apneas, hypopneas, AHI, obstructive AHI, and several indicators of hypoxia during sleep.

Effect of mandibular distraction osteogenesis on the temporomandibular joint: a systematic review of animal experimental studies

The present systematic review aimed to test the hypothesis of no effect of mandibular distraction osteogenesis on the temporomandibular joint. Animal experimental studies from January 1985 to August 2013 were included. Studies were searched in PubMed, Embase, Scopus, and the Cochrane Library. A total of 289 articles were identified, and 17 were included. Included studies were characterized by a high risk of bias and by inhomogeneity related to animal species, experimental procedures, and evaluation methods. Mandibular distraction osteogenesis within physiologic limits may be followed by adaptive changes in bone, disk, and cartilage. Increased daily rates and total activation length may influence the severity of the adaptive changes. Animal experimental studies indicate that mandibular distraction osteogenesis may induce adaptive changes in the temporomandibular joint. Adaptive changes may be influenced by increased daily rates and total length of distraction osteogenesis. Well-designed studies are needed before final conclusions can be drawn.

Mandibular distraction osteogenesis in the management of airway obstruction in children: a systematic review protocol

Review question/objective What is the effectiveness of mandibular distraction osteogenesis on airway patency and long-term development in children born with upper airway obstruction secondary to micrognathia? More specifically: Does mandibular distraction result in improved short- and long-term outcomes compared with tracheostomy? What is the ideal daily rate of mandibular distraction, and does the ideal rate differ between age groups? Inclusion criteria Types of participants This review will consider studies that include: 1. Male and female children with clinical evidence of Pierre Robin Sequence or mandibular hypoplasia from birth 2. Children with upper airway obstruction for whom conservative treatments have failed 3. Syndromic and non-syndromic children with micrognathia 4. Children who have undergone bilateral mandibular distraction for consideration of decannulation and removal of a tracheostomy This review will not consider studies that include: 1. Children who underwent unilateral mandibular distraction 2. Children with central apnea, or acquired conditions that lead to airway obstruction for example trauma, iatrogenic injury and tongue disorders 3. Children with known abnormalities beyond the tongue base: hypopharynx and lower airway. Types of intervention(s)/phenomena of interest This review will consider studies that evaluate mandibular distraction osteogenesis. Comparator: tracheostomy Types of outcomes This review will consider studies that include the following outcome measures: Primary outcomes: - Airway patency/Reversal of apnea - Decannulation of tracheostomized patients - Feeding and weight gain - Gastro-oesophageal reflux Secondary outcomes: - Long-term outcomes – facial development and future surgical intervention - Surgical outcomes

The Long-Term Effects of Mandibular Distraction Osteogenesis on Developing Deciduous Molar Teeth

Background. Many studies have demonstrated the effectiveness of mandibular distraction osteogenesis (MDO) in alleviating the micrognathia-associated upper airway obstruction but very few studies have focused on long-term dental outcomes. Objective. To report the effect of MDO on developing deciduous molars in the distraction area. Methods. A retrospective chart review was performed to identify patients with Pierre Robin sequence who underwent MDO with documented long-term dental assessments. Results. Ten children (mean age at surgery 69.8 days; 6 boys and 4 girls) were included for analysis. All patients underwent bilateral MDO with an inverted L-shaped osteotomy to avoid injuring tooth buds. The dental developmental stage was primary dentition in all children. Overall, 3 patients developed minor dental problems involving 4 molar teeth (2 root malformations and 2 shape anomalies) but they did not require any interventions. Conclusion. Significant primary molar developmental complications were not seen in our patients. The use of internal distractor device with an inverted L-shaped osteotomy seems to be a safe surgical approach in regards to dental outcomes.

Mandibular distraction osteogenesis for neonates with Pierre Robin sequence and airway obstruction

Neonates with Pierre Robin Sequence (PRS) usually present with varying degrees of upper airway obstruction and difficulty feeding. Early treatment is important for such children in order to prevent impaired cognitive development resulting from hypoxemic episodes. Various procedures aimed at widening the pharyngeal space have been proposed, including prone position, tongue-lip adhesion, mandibular traction, non-invasive ventilation and palatal plates. Mandibular distraction osteogenesis (MDO) using external or internal devices has become increasingly popular as an alternative treatment option when other medical or surgical techniques do not prove to be satisfactory. This review summarizes current evidence on the effectiveness of MDO in infants with PRS. Because of a lack of studies comparing this treatment with other procedures, general recommendations cannot be drawn and treatment of infants with PRS still requires individualization.