Condylar restoration after early TMJ fractures and functional appliance therapy. Part I: Remodelling

Functional Orthodontic Treatment of Mandibular Condyle Fractures in Children and Adolescent Patients: An MRI Follow-Up

BACKGROUND

The purpose of this study was to retrospectively evaluate and follow up a conservative treatment approach with functional orthodontic appliances for the management of mandibular condyle fractures in children and adolescent patients.

METHODS

Between 2020 and 2022, the treatment records of patients with mandibular condyle fractures receiving a functional orthodontic treatment (FOT) were evaluated. In addition to the clinical and functional findings, magnetic resonance images of the mandibular condyles and surrounding structures were assessed.

RESULTS

Out of 61 patients, 8 met the inclusion criteria. The follow-up examination records showed no functional limitations. In 75% of cases, mild midline deviations persisted (mean 1.1 mm) without significant alterations to the occlusal relationships. Magnetic resonance imaging (MRI) showed the remodeling of the condyles and the restitution of the ramus heights, even in dislocated and displaced fractures. In three cases, a partial displacement of the articular disc was observed at the follow-up. No differences in the remodeling patterns were noted depending on age, sex, or fracture location.

CONCLUSIONS

A FOT led to favorable functional and morphologic outcomes, supporting the concept of a conservative functional approach in children and adolescent patients. Functional adjunctive therapy should be considered in the conservative treatment of mandibular condyle fractures in growing patients.

Functional appliance treatment for mandibular fractures: A systematic review with meta-analyses

OBJECTIVES

Mandibular collum fractures among growing patients can lead to abnormal growth, function, esthetics and ultimately quality of life. Among the proposed treatment alternatives, orthopaedic treatment with functional appliances has been suggested, with encouraging results. Aim of the present systematic review was to critically appraise existing evidence on the outcome of functional appliance treatment among growing patients with mandibular collum fractures.

MATERIALS AND METHODS

Eight databases were searched up to October 2020 for randomised and non-randomised clinical studies assessing functional appliance treatment outcome for children with mandibular fractures. After duplicate study selection, data extraction and risk of bias assessment, random effects meta-analyses of mean differences (MD) and their 95% confidence intervals (CIs) were performed, followed by assessment of the quality of evidence with GRADE.

RESULTS

A total of 8 unique studies (one prospective and nine retrospective non-randomised) with 223 children could be identified. Functional appliance treatment was associated with greater anteroposterior condyle dimensions of the injured condyle compared with the contralateral healthy condyle (3 studies; MD = 0.87 mm; 95% CI = 0.30 to 1.45 mm; p = .003). No difference was found in the mesiodistal condyle size between the injured and the contralateral healthy joint (3 studies; MD = -0.05 mm; 95% CI = -1.05 to 0.95 mm; p = .92), but collum length was smaller at the injured side compared with the contralateral one (1 study; MD = -2.89 mm; 95% CI = -5.29 to -0.49 mm; p = .02). Treatment outcome might be influenced by patient age, patient sex and severity/localisation of the fracture, but the quality of evidence for all analyses was very low due to methodological limitations leading to bias.

CONCLUSIONS

While some evidence exists that functional appliances might lead to good clinical rehabilitation of fractured mandibular condyles, including considerable bone remodelling, available studies are small and have methodological weaknesses.

Radiographic Assessment of Pediatric Condylar Fractures after Conservative Treatment with Functional Appliances-A Systematic Review

Background: To evaluate the effectiveness of conservative treatment with functional appliances for condylar fractures in pediatric age. Methods: Four electronic databases (PubMed, EBSCO, Scopus, and Web of Science) were consulted with no restriction of publication status or year, up to 31 August 2020. Selection criteria: based on the PICOS criteria, the selection criteria were set for observational human studies, with at least 10 patients and six months of follow-up. The study population included pediatric patients (aged 5–16 years), with unilateral or bilateral condylar fracture, treated with functional appliances. Condylar remodeling and mandibular growth were analyzed through sequential radiographic examinations. Data collection and analysis: Two independent reviewers carried out title-abstract screening, and a senior investigator was involved to solve any disagreement. The quality of the evidence was assessed through the Canada Institute of Health Economics (IHE) quality appraisal checklist, and the National Institutes of Health (NIH) quality assessment tool. Results: A total of 971 articles were retrieved from the electronic search; among them, three studies met the eligibility criteria. A moderate risk of bias was detected in all the studies, due to common limitations (absence of multicenter studies, prospective design, blindness of the investigators, patients’ drop-out). At follow-up examinations (between 6 months and 4.9 years), the difference of condylar neck length between the “injured” and “healthy” side was approximately 2 mm, while the anteroposterior condylar width discrepancy was recorded up to 1 mm. Conclusions: Short- and long-term data revealed that conservative treatment with functional appliances led to partial or full radiological recovery of the joint morphology, along with good to excellent functional results. Patients’ age has a crucial role on the treatment choice, and the type of fracture (presence of condylar displacement, or dislocation) is also a major prognostic indicator of the radiologic outcome. Limitation: To confirm the effectiveness of functional appliances, more prospective clinical long-term follow-up studies with homogeneous samples of condylar fractures are deemed necessary. Registration: The study protocol was registered on PROSPERO (CRD42020205650).

Abduction of the condyle head leads to condylar resorption: A radiologic study in children with intracapsular fractures

OBJECTIVE

This study aimed to explore and make an understanding of absorption existed in children with intracapsular fractures.

METHODS

The sample was composed of all children (less than 12 years) who presented with intracapsular fractures within a 5-year period (January 2011 to April 2016). Data about age, gender, date of injury, dates of admission and discharge, transfer and/or referral by other clinics or local facilities, mechanism of trauma, location and pattern of fracture, associated injuries, centimeter of mouth opening, treatment methods, image date of pre- and post-treatment (including time of review), position of condylar head in pre-treatment or post-treatment, and absorption of condylar head in pre-treatment or post-treatment were recorded and analyzed. Data analysis included the Chi-Square test, the Fisher exact test, and the t-test. Logistic regression analysis was utilized to control the confounding variables. Probabilities of p less than 0.05 were considered statistically significantly different.

RESULTS

In the 5 years records retrieved during this study, 93 children patients sustained a total of 140 condylar head fractures. Statistical analysis revealed that abduction of condylar process in post-treatment was highly related to the condylar absorption. Patients associated with other mandibular fractures were highly related to abduction of condylar process. Patients with condylar head fractures, the closer to the medial of the condylar process, the higher the risk of abduction of the condyle. No matter what kind of treatment method is used, it is very difficult to reverse the abduction of condylar process in children patients with intracapsular fractures efficaciously.

CONCLUSION

Abduction of condylar process in post-treatment was highly related to the condylar absorption. Patients associated with other mandibular fractures were highly related to abduction of condylar process. Children patients who presented with condylar head fractures, the closer to the medial of the condylar process the higher the risk of abduction of the condyle. Neither surgery nor conservative treatment can recover the abduction of condylar process efficaciously.

Conservative treatment of bilateral condylar fractures in children: case report and review of the literature

Two children (11 year old) with bilateral condylar fractures associated with symphysis fracture were conservatively treated. Both of them were followed up for about 1 year. A review of 21 cases of bilateral condylar fracture available in the literature revealed the younger the patient, the better the outcome of TMJ function or in radiographic remodeling. However, the longer the time elapsed, the higher the incidence of remodeling deformity and dysfunction. Thus, it must be better that a close follow-up of bilateral condylar fracture in children should be continued until the end of growth period.

Open versus closed reduction: mandibular condylar fractures in children

PURPOSE

The purpose of the study was to review the literature regarding the evolution of current thoughts on management of mandibular condylar fractures (MCFs) in children.

METHODS

An electronic search in PubMed was undertaken in May 2012. The titles and abstracts from these results were read to identify studies within the selection criteria. Eligibility criteria included studies published in English or German from the last 20 years (from 1992 onwards) reporting clinical series of MCFs in children and adolescents until the age of 18.

RESULTS

The search strategy initially identified 542 studies. The references from 1992 onwards totaled 339 articles. Twenty-seven studies were identified without repetition within the selection criteria. Additional hand-searching yielded two additional papers.

CONCLUSIONS

Pediatric MCFs require thoughtful consideration in management to avoid significant growth disturbance. Early treatment is indicated in order to improve the chances for favorable development. Long-term follow-up is required, in order to properly treat late complications that may appear. Coronal computed tomography is helpful in substantiating the correct final diagnosis. Many studies show that conservative treatment (CTR) has satisfactory long-term outcome of jaw function, occlusion, and facial esthetics, despite a high frequency of radiological aberrations. Surgery before puberty should be reserved for exceptional cases such as missile injuries, in cases with extensive dislocation and lack of contact between the fragments, in cases with multiple midfacial fractures, in which the mandible has to serve as a guide to reposition the midfacial bones, and in cases which the dislocation of the fractured stump creates a functional impediment that cannot be resolved by CTR. As the craniofacial skeleton becomes more adult-like in its form at about 12 years of age, the decreased remodeling capacity in the adolescents may occasionally result in abnormally shaped condylar heads or shortened ramus heights that may lead to persistent malocclusion. Thus, the indication of open reduction and internal fixation increases with age.

Early complete bone union after condylar fracture in a child

A 3-year-old boy had unilateral intracapsular condylar fracture due to a fall. Short duration of immobilization using a facial band was performed for 5 days without any surgical intervention. The patient had full recovery in mouth opening with no deviation or asymmetry of the mandible. Posttraumatic 6 weeks later, the patient's computed tomogram revealed complete reduction of fracture, and bone union had occurred. In condylar fractures of children, treatment protocols with short duration of immobilization and early active exercise can obtain complete bone union, contrary to the previously described deformity or remodeling process.

Adaptive adjustment of the adolescent porcine mandibular condyle

The effect of occlusal support during primary dentition on the mandibular condyle remains controversial. We sought to determine whether unilateral loss of occlusal support leads to quantifiable adaptive changes of the condyle. Quantitative analysis of condylar growth and spongy bone volume after unilateral removal of teeth on the left side in adolescent minipigs was examined over a period of 4 months. Serial sagittal sections of the temporomandibular joint were examined using microradiography, fluorescence microscopy, and light microscopy. The condyles on the nonextracted side showed a higher growth rate than those on the extracted side, with a 1.56-fold thicker (p = 0.003) additional vertical bone layer. This factor was greater ventrally than dorsally (p = 0.0311), increasing from dorsomedial (1.33) to ventrolateral (2.38). There was therefore a reciprocal change of the condylar surface curve between the left and right condyles. Increased condylar growth correlated with a lower subchondral spongy bone volume (7.38% difference, p = 0.002). The amount of mineralized bone matrix generated was estimated to be about 1.33-fold higher in the nonextraction side condyles compared with those on the extraction side. Thus, unilateral loss of occlusal support was shown to lead to quantifiable alterations of condylar vertical growth and spongy bone volume in minipigs.

Condylar restoration after early TMJ fractures and functional appliance therapy. Part II: Muscle evaluation

The aim of this study was to analyze and to describe the condition of the lateral pterygoid muscle during and after functional appliance therapy in children who had sustained condylar fractures. The treatment group consisted of 19 patients with an average age of 13.4 years, who had sustained a unilateral fracture at an average age of 8.4 years and had been treated functionally for 6 to 8 months. Muscle condition was assessed through axial soft tissue description. The volume and density of the lateral pterygoid muscle were measured in both groups and were compared on the basis of sex, age and fracture type. 74% of the patients in the follow-up group showed muscle differences of more than 10% between the 2 sides. In 2/3 of these patients the lateral pterygoid of the fracture side was 13 to 69% smaller. The volumes of the contralateral pterygoid muscles in the 2 patient groups differed by 10% on the basis of sex. Both in the treatment group and in the follow-up group the volume difference between the healthy and fractured side was as high as 70% depending on localization and type of fracture. Deep fractures and fractures with complete dislocation of the condyle evoked the most serious reduction in muscle volume.