An unusual complication of mandibular distraction

Congenital Trismus From Brainstem Dysgenesis: Case Report and Review of Literature

Trismus refers to any condition inducing limited mouth opening and may present as a result of acquired or congenital pathology. We present the case of a newborn who presented with severe, congenital trismus due to brainstem dysgenesis. We describe the course of his investigations, and a multidisciplinary approach to the management of his care and follow-up. To our knowledge, this is one of the earliest reported cases of congenital trismus attributable to brainstem dysgenesis. A literature review was conducted to provide an overview of the differential pathogenesis as it presents in congenital cases and discuss the complexity of managing congenital trismus due to brainstem dysgenesis in a neonate and infant.

Distraction Osteogenesis for Management of Severe OSA in Pierre Robin Sequence: An Approach to Elude Tracheostomy in Infants

BACKGROUND

Severe obstructive sleep apnoea (OSA) is a life threatening condition associated with Pierre Robin sequence (PRS) due to mandibular micrognathia and glossoptosis. Often these patients require tracheostomy at an early age which has high morbidity. Distraction osteogenesis (DO) is an accepted method of treatment for patients with hypoplastic mandible to achieve mandibular lengthening without need for a bone graft. It has also been used in respiratory distressed neonates and infants to avoid tracheostomy.

CASE REPORT

An eight month old baby, a diagnosed case of PRS with severe OSA and recurrent episodes of aspiration pneumonia and on nasogastric tube feeding since birth was referred to us for evaluation and possibility of therapeutic augmentation of the mandible by DO. After a thorough clinico-radiological assessment the child was operated for bilateral extraoral placement of horizontal corpus distractor. A total distraction of 12 mm was carried out and consolidation of callus was monitored by USG. Postoperatively the patient was followed up for 12 months. Presently she has normal respiratory and feeding function without any episode of aspiration pneumonia.

CONCLUSION

Mandibular corpus DO is a safe and effective technique that can be applied to predictably relieve severe upper airway obstruction in selected PRS cases. In order to avoid the limitations of alternative surgical procedures and the tracheostomy-associated morbidity, DO should be considered among the routine treatment modalities.

The effectiveness of mandibular distraction in improving airway obstruction in the pediatric population

BACKGROUND

Distraction osteogenesis is an effective technique for elongating the deficient mandible. The authors specifically evaluated its effectiveness in the treatment of airway obstruction in pediatric patients with mandibular hypoplasia.

METHOD

A comprehensive literature review of the National Library of Medicine (PubMed) database was performed. English-language studies involving isolated distraction of the pediatric mandible (younger than 18 years) with descriptive reporting of airway changes were included. Extracted data included demographics, initial diagnosis, distractor type, distraction protocol, predistraction and postdistraction airway status, and complications.

RESULTS

Seventy-four articles met the inclusion criteria, resulting in 711 patients with craniofacial abnormalities who underwent mandibular distraction osteogenesis. Mean age at the time of distraction was 18.1 months. The most common diagnoses were isolated Pierre Robin sequence (52.9 percent), syndromic Pierre Robin sequence (7 percent), and Treacher Collins syndrome (6.8 percent). Mandibular distraction osteogenesis successfully treated airway obstruction in 89.3 percent of cases. Success was defined as either decannulation of tracheostomy, avoidance of tracheostomy or continuous positive airway pressure, or alleviation or significant improvement of obstructive sleep apnea symptoms. One hundred seventy-one (84.2 percent) of the 203 tracheostomy-dependent patients were successfully decannulated. Among the 181 patients with obstructive sleep apnea, mandibular distraction osteogenesis successfully allowed for either complete resolution or significant improvement of symptoms in 95.6 percent. A 23.8 percent overall complication rate was noted. The mean follow-up time was 28.7 months.

CONCLUSION

In addition to its positive effect on facial appearance, mandibular distraction osteogenesis is an effective procedure for the treatment of airway obstruction associated with congenital craniofacial defects involving mandibular hypoplasia in appropriately selected patients.

Neonates with Tongue-Based Airway Obstruction

Objective. In this systematic review, the authors summarize the current evidence in the literature regarding diagnosis, treatment, and long-term outcomes in neonates with tongue-based airway obstruction (TBAO) and assess the level of evidence of included studies.

Data Sources. The terms Pierre Robin syndrome/sequence, micrognathia, retrognathia, and cleft palate were combined with airway obstruction, treatment, tongue-lip plication, and osteogenesis distraction to perform an Ovid literature search, yielding 341 references. The authors excluded references containing patients with isolated choanal/nasal obstruction, patients older than 12 months, and expert opinion papers, yielding 126 articles.

Review Methods. The authors searched 3 electronic databases and reference lists of existing reviews from 1980 to October 2010 for articles pertaining to the diagnosis, treatment, and outcomes of TBAO. Reviewers assigned a level of evidence score based on Oxford’s Centre for Evidence Based Medicine scoring system and recorded relevant information.

Results. Most studies were case studies and single-center findings. The lack of standardization of diagnostic and treatment protocols and the heterogeneity of cohorts both within and between studies precluded a meta-analysis. There was little evidence beyond expert opinion and single-center evaluation regarding diagnosis, treatment, and long-term outcomes of neonates with TBAO.

Conclusions. The variability in the phenotype of the cohorts studied and the absence of standardized indications for intervention preclude deriving any definitive conclusions regarding diagnostic tools to evaluate this patient population, treatment choices, or long-term outcomes. A coordinated multicenter study with a standardized diagnostic and treatment algorithm is recommended to develop evidence for the diagnosis and treatment of neonates with TBAO.

Meta-analysis of mandibular distraction osteogenesis: clinical applications and functional outcomes

BACKGROUND

Mandibular distraction osteogenesis has been used effectively to treat syndromic craniofacial deformities. In recent years, its scope of application has widened to include treatment of airway obstruction in adults and children and nonsyndromic class II mandibular hypoplasia. So far, there has been no evidence-based review of mandibular distraction osteogenesis for mandibular lengthening.

METHODS

Two rounds of searches were performed by two independent assessors. The first-round PubMed search used the keywords "mandible" and "distraction osteogenesis." In the second-round search, the reference lists of the articles were retrieved. For both rounds, abstracts and then full articles were reviewed and selected on the basis of a set of inclusion and exclusion criteria.

RESULTS

The 178 retrieved articles yielded 1185 mandibular distraction osteogenesis patients: 539 received unilateral mandibular distraction osteogenesis and 646 received bilateral mandibular distraction osteogenesis. Mandibular distraction osteogenesis was reported to improve facial asymmetry and retrognathia (50.1 percent), correct the slanted lip commissure (24.7 percent), and improve or level the mandibular occlusal plane (11.1 percent) in unilateral asymmetry cases, whereas bilateral mandibular distraction osteogenesis was shown to be effective in preventing tracheostomies for 91.3 percent of neonates or infants with respiratory distress, and in relieving symptoms of obstructive sleep apnea for 97.0 percent of children and 100 percent of adult patients.

CONCLUSIONS

Mandibular distraction osteogenesis is effective in treating craniofacial deformities, but further clinical trials are required to assess the long-term stability and to compare the treatment with conventional treatment methods, especially in cases of obstructive sleep apnea or class II mandibular hypoplasia.

Dentigerous cyst after distraction osteogenesis of the mandible

Damage to the dentition or tooth follicle is often cited as a potential complication of Distraction Osteogenesis (DO). The authors describe a case of a dentigerous cyst that developed following DO of the mandible. The possible histogenic mechanisms and the management are outlined. Understanding the causes of dentigerous cysts as well as the anatomy of the neonatal mandible may help avoid such a complication in the future.