Hemandibular Hypoplasia Successfully Treated with Functional Appliances: Is it Truly Hemifacial Microsomia?

Management of unilateral craniofacial microsomia with orthopaedic functional appliances: A systematic literature review

The study aimed to summarize current knowledge regarding the use of orthopaedic functional appliances (OFA) in managing unilateral craniofacial microsomia (UCM). The eligibility criteria for the review were (1) assessing use of OFA as a stand-alone treatment and (2) using OFA in combination during or after MDO. The PICO (population, intervention, comparison and outcome) format formulated clinical questions with defined inclusion and exclusion criteria. No limitations concerning language and publication year were applied. Information sources: A literature search of Medline, Scopus, Embase, Cochrane Central Register of Controlled Trials, Web of Science databases without restrictions up to 30 September 2022. The risk of bias was assessed. According to Cochrane and PRISMA guidelines, two independent authors conducted data extraction. The level of evidence for included articles was evaluated based on the Oxford evidence-based medicine database. Due to the heterogeneity of studies and insufficient data for statistical pooling, meta-analysis was not feasible. Therefore, the results were synthesized narratively. A total of 437 articles were retrieved. Of these, nine met inclusion criteria: five assessing OFA and four assessing OFA during or after MDO. There is limited evidence to suggest that stand-alone and combination treatment with OFA is beneficial for treating mild-to-moderate UCM-related dentofacial deformities in short term. No studies assessed the burden of care. In the management of UCM, there is insufficient evidence supporting the efficacy of OFA as a stand-alone treatment or when combined with MDO. Additionally, there is a lack of evidence regarding treatment protocols and the effect on the condyles and the TMJ. The study was registered at Prospero database number CRD42020204969.

Growth characteristics and classification systems of hemifacial microsomia: a literature review

BACKGROUND

Hemifacial microsomia is characterized by the hypoplasia of the mandible and temporomandibular joint, involving a variety of abnormalities of the craniofacial area. Since it gradually worsens as patients grow, it is necessary to understand the characteristics of facial bone growth and facial deformity in hemifacial microsomia patients in order to determine appropriate treatment timing and treatment methods.

MAIN BODY

Appropriate classification of hemifacial microsomia would facilitate accurate diagnosis, selection of treatment methods, and prognosis prediction. Therefore, in this article, we review previously published hemifacial microsomia classification and provide an overview of the growth of the facial skeleton and the characteristics of hemifacial microsomia-related facial deformities. The OMENS system is the most comprehensive classification method based on the characteristics of hemifacial microsomia deformity, but it needs to be improved to include malar/midface abnormalities and nerve involvement. In hemifacial microsomia, growth is progressing on the affected side, but to a lesser degree than the unaffected side. Therefore, surgical intervention in growing patients should be performed selectively according to the severity of deformity.

CONCLUSION

Understanding growth patterns is important to develop appropriate treatment protocols for correcting asymmetry in adult patients and to minimize secondary anomalies in growing patients.

Dental anomalies in craniofacial microsomia and condylo-mandibular dysplasia: A retrospective study of 103 patients

INTRODUCTION

Craniofacial microsomia (CFM) and camel-hump condylo-mandibular dysplasia (CMD) are developmental disorders affecting the mandible that share common clinical features. This study aimed to investigate and compare the dental anomalies (DA) between the two entities for differential diagnosis and to propose appropriate treatment.

METHODS

This retrospective cross-sectional study was based on panoramic radiographs of patients diagnosed with CFM or CMD. DA were evaluated using the classification reported by Bilge. Delayed tooth eruption on the affected side was noted based on a comparison with the contralateral side. Nolla's stages of tooth calcification were used to assess dental development.

RESULTS

A total of 103 patients were included, 80 subjects (77.7 %) in CFM group and 23 patients (22.3 %) in CMD group. The prevalence of DA among CFM and CMD-affected patients were 80.0 % and 95.7 %, respectively. Tooth ectopia, tooth impaction, dental development delay, and delayed tooth eruption on the affected side exhibited a significant association with the two craniofacial malformations. The overall affected teeth (molars, premolars, canines) differed between the two craniofacial malformations. Dental abnormalities such as oligodontia, hyperdontia, dentin dysplasia, and anomalies of shape were seen only in subjects affected by CFM.

CONCLUSION

DA were widely observed in patients with CFM and CMD. The global distribution of affected teeth differed between the two conditions and some DA were detected only in CFM patients. When clinical diagnosis remains uncertain, some specific radiological characteristics of DA can be used to differentiate CFM from CMD.

True hemifacial microsomia and hemimandibular hypoplasia with condylar-coronoid collapse: diagnostic and prognostic differences

INTRODUCTION

Long-term results after orthopedic or surgical treatment of hemifacial microsomia (HFM) have shown a tendency toward recurrence of the facial asymmetry. However, the literature contains a number of successful case reports that show surprising changes in the morphology of the condyles. In addition, patients with similar mandibular asymmetries, treated early with surgery, have excellent long-term follow-ups, especially those who have little or no soft-tissue involvement, but only severe mandibular ramal deformities. The phenotypes of these cases are unexpectedly similar, with a consistent collapse of the condyle against the coronoid and a deep sigmoid notch. The objectives of this article were to help distinguish true HFM from this peculiar type of hemimandibular asymmetry morphologically and to quantify their differences before treatement and in the long term.

METHODS

Panoramic radiographs taken at pretreatment and the long-term follow-up of 9 patients with hemimandibular hypoplasia, characterized by the collapse of the condyle against the coronoid, were compared with those of 8 patients with severe type I and type II HFM; these records were collected before and at least 10 years after distraction osteogenesis.

RESULTS

Ratios and angular measurements before and after treatment differed significantly between the 2 groups.

CONCLUSIONS

Perhaps these patients were misdiagnosed and actually had secondary injuries of the condyle, which have a normal functional matrix. Therefore, with growth and functional stimulation, they would tend to grow toward the original symmetry. To make a differential diagnosis between true HFM and this peculiar type of hemimandibular hypoplasia, the collaboration between not only orthodontists and surgeons, but also geneticists and dysmorphologists, is of great importance because of the different prognoses.

The importance of a differential diagnosis between true hemifacial microsomia and pseudo-hemifacial microsomia in the post-surgical long-term prognosis

Long-term results after surgical treatment of the mandibular asymmetry in growing children with hemifacial microsomia (HFM), whether with osteotomies or distraction osteogenesis, have mostly shown a tendency towards the recurrence of the asymmetry. In contrast, in the literature we find sporadic case reports where the long-term post-surgical follow-up of patients diagnosed as HFM, are surprisingly stable. All these reports refer to patients who have substantially no soft tissue involvement, but only severe mandibular ramus and condyle deformities. The phenotypes of these cases are unexpectedly similar. The authors suggest, that it is possible that all of these cases might be isolated hemimandibular hypoplasias, misdiagnosed as HFM, which present a normal functional matrix and, therefore, tend to grow towards the original symmetry. Differential diagnosis between true HFM and this HFM-like isolated hemimandibular hypoplasia (pseudo-HFM) is of great importance given the very different prognosis and it is possible through the collaboration between not only surgeons and orthodontists, but also of geneticists and dysmorphologists.

No evidence for long-term effectiveness of early osteodistraction in hemifacial microsomia

BACKGROUND

The authors performed a critical literature review to find evidence of the long-term stability after early distraction osteogenesis of the mandible in patients with hemifacial microsomia.

METHODS

The PubMed, Cochrane, MEDLINE, EMBASE, CENTRAL, and CINAHL databases were searched systematically for studies performed between 2002 and 2008. Abstracts from the 89 relevant articles were reviewed for evidence.

RESULTS

Thirteen articles met the inclusion criteria. Data were tabulated with respect to the length of follow-up, number of patients, age group, Pruzansky-Kaban classification of the patients, methods of analysis and validation, and level of evidence. Methods for long-term follow-up studies were not standardized, and no objective studies have been published on stability after growth cessation.

CONCLUSIONS

Thus far, no randomized controlled trials on early distraction osteogenesis in hemifacial microsomia patients have been published. The authors conclude that there is a lack of statistical evidence to support the use of early distraction osteogenesis for correcting hemifacial microsomia as a single treatment modality. The results call into question its rationale.