Temporomandibular Joint Prosthesis in a Patient with Congenital Infiltrating Lipomatosis of the Face with Bony Ankylosis of the Temporomandibular Joint: A Case Report.

Hemifacial hyperplasia (HFH) is a rare congenital disorder characterized by marked unilateral overgrowth of the facial tissues. A subtype of HFH is congenital infiltrating lipomatosis of the face (CIL-F). This disease is characterized by unilateral diffuse infiltration of mature adipose cells in the facial soft tissue and is associated with skeletal hypertrophy. This work aims to report a case of a CIL-F patient with right facial asymmetry and progressive growth at adolescent age, causing mandibular asymmetry due to signs of concomitant unilateral condylar hyperplasia. At the age of seventeen, a condylectomy was performed to stop the progression of asymmetric mandibular growth. Five years later, the patient developed CIL-F-associated temporomandibular joint ankylosis, manifesting as progressive restricted mouth opening along with temporal facial pain. In this CIL-F patient, a TMJ reconstruction with an alloplastic total joint prosthesis was successfully performed with optimal maximal mouth opening, complete alleviation of temporal facial pain, and stable dental occlusion one year postoperatively. A TMJ reconstruction with a complete alloplastic total joint prosthesis proved to be a predictable, stable, and safe treatment option in a patient with CIL-F-associated TMJ ankylosis who was previously treated with condylectomy due to progressive mandibular asymmetry.

Reproducibility of 2D and 3D Ramus Height Measurements in Facial Asymmetry.

In our clinic, the current preferred primary treatment regime for unilateral condylar hyperactivity is a proportional condylectomy in order to prevent secondary orthognathic surgery. Until recently, to determine the indicated size of reduction during surgery, we used a 'panorex-free-hand' method to measure the difference between left and right ramus heights. The problem encountered with this method was that our TMJ surgeons measured differences in the amount to resect during surgery. Other 2D and 3D method comparisons were unavailable. The aim of this study was to determine the most reproducible ramus height measuring method. Differences in left/right ramus height were measured in 32 patients using three methods: one 3D and two 2D. The inter- and intra-observer reliabilities were determined for each method. All methods showed excellent intra-observer reliability (ICC > 0.9). Excellent inter-observer reliability was also attained with the panorex-bisection method (ICC > 0.9), while the CBCT and panorex-free-hand gave good results (0.75 < ICC < 0.9). However, the lower boundary of the 95% CI (0.06−0.97) of the inter-observer reliability regarding the panorex-free-hand was poor. Therefore, we discourage the use of the panorex-free-hand method to measure ramus height differences in clinical practice. The panorex-bisection method was the most reproducible method. When planning a proportional condylectomy, we advise applying the panorex-bisection method or using an optimized 3D-measuring method.

A conceptual framework for treating jaw deformities in patients with abnormal condyles: preservation versus replacement of the glenoid fossa-disc-condyle-ramus.

This article outlines a conceptual approach to the reconstruction of jaw deformities associated with abnormalities in the mandibular condyle. The authors describe a hierarchy of reconstruction, emphasizing use of the least invasive and progressing to the most complex and invasive techniques, depending on the nature and severity of the underlying deformity, prior operations, patient age, and stage of growth. Consider joint preservation orthognathic surgical correction, followed by biological techniques for replacement of the condyle, and avoid replacing a functional temporomandibular joint based only on radiographic remodeling and concerns about potential future flare-ups of disease based on anecdotal data.

Unilateral condylar hyperplasia in hemifacial hyperplasia, is there genetic proof of overgrowth?

Hemifacial hyperplasia (HFH) is characterized by an increase in volume of all affected tissues of half of the face. It is present at birth, subsequently grows proportionally, and stops growing before adulthood. Unilateral condylar hyperplasia (UCH) consists of progressive asymmetric growth of the mandible and develops typically in early adulthood. Both disorders have an unknown aetiology. The overgrowth limited to one body part suggests somatic mosaicism, as this has been found in other similar localized overgrowth disorders. Often this includes a variant in a gene in the (PIK3CA)/PI3K/(PTEN)/AKT1/mTOR pathway. Here we report the case of an HFH patient with asymmetry present at birth, in whom a progressive growth pattern similar to UCH subsequently occurred, causing marked mandibular asymmetry. A condylectomy was successfully performed to stop the progressive growth. Somatic mosaicism for a mutation in PIK3CA was detected in the condylar tissue. This finding might indicate that both HFH and UCH can be caused by variants in genes in the (PIK3CA)/PI3K/(PTEN)/AKT1/mTOR pathway, similar to other disorders that result in asymmetrical bodily overgrowth.

Molecular basis of unilateral condylar hyperplasia?

Unilateral condylar hyperplasia (UCH) causes progressive asymmetry of the mandible. The aetiology of this growth disorder is unknown. A two-centre prospective study was established, and 10 consecutive adult UCH patients scheduled for high condylectomy were included. The resected condylar tissue was divided into two parts, one for regular histopathology and one for DNA extraction. A panel of eight selected overgrowth genes (AKT1, AKT3, MTOR, PIK3CA, PIK3R2, PTEN, TSC1, TSC2) were sequenced using next-generation sequencing, with coverage of a minimum 500 times in order to be able to detect low-grade mosaicisms. Subsequently, untargeted whole exome sequencing (WES) was performed to detect variants in other genes present in three or more patients. No mutation was detected in any of the overgrowth genes, and untargeted exome sequencing failed to detect any definitively causative variant in any other gene. Ten genes had a rare variant in three or more patients, but these cannot be designated as causative without additional functional studies. The hypothesis that the cause in at least some patients with UCH is a somatic mutation in a gene that controls cell growth could not be confirmed in this study.

Three-dimensional skeletal changes after early proportional condylectomy for condylar hyperplasia.

The purpose of this study was to evaluate volumetric and dentoskeletal changes in 21 patients with active unilateral condylar hyperplasia (AUCH) after proportional condylectomy. A split-mouth design was used: control group healthy joints (HS, healthy side) and test group affected joints (AS, affected side) (21 per group). Cone beam tomography scans were obtained at T0 (preoperative), T1 (10days after the intervention), and T2 (approximately 12 months post-surgery). The condylar unit volume (CUV), articular cavity volume (ACV), and dentoalveolar units (DAUs) were measured. CUV showed a difference of 1.12cm3 between T0 and T1, increasing 0.4cm3 between T1 and T2 on AS. There was no difference between T0 and T2 on HS. ACV increased 0.65cm3 between T0 and T1 on AS, after which it decreased by 0.36cm3 at T2 (0.30cm3 larger than the initial articular cavity at T0). ACV showed no post-surgery differences on HS. Midline DAU showed extrusion of 0.20mm for maxilla and 0.52mm for mandible, while in the lateral area, maxilla was extruded by 0.3mm on HS and was intruded 0.12mm on AS. For the mandible, both sides showed extrusion (0.4-0.6mm). In the distal to canine and molar areas, intrusion of 0.2mm and 0.9mm, respectively, was observed on AS; there was extrusion of 0.6mm distal to the canine on HS. At the mandibular level, AS distal to the canine showed extrusion of 1mm, while intrusion of 0.2mm was observed in the molars. For HS, only extrusion at the molar level (0.2mm) was observed. In conclusion, after proportional condylectomy, a neocondyle forms within 12 months to equal the healthy contralateral side. The articular cavity, which is reduced in the initial stage, increases in size after surgery and the volume gradually approaches that of the healthy side. Dentoalveolar changes occur at the anterior and posterior levels, causing intrusion and extrusion of the interdental crests. An early proportional condylectomy as the sole surgical treatment for patients with AUCH allows normalization of the maxillomandibular relationship.

Ten years of observations and demographics of hemimandibular hyperplasia and elongation.

INTRODUCTION: The full epidemiology and etiology of hemimandibular hyperplasia (HH) has not yet been clarified. In most cases it starts before puberty and results in various forms of dento-alveolar and skeletal discrepancies. This study is the first attempt at evaluating and describing some of the authors' key experiences, clinical philosophical approach, and gathered demographic data on hemimandibular hyperplasia and hemimandibular elongation (HE) among the Polish population. MATERIAL AND METHOD: A total of 45 patients (M = 8; F = 37; p < 0.05) with HE (n = 16; 35.6%; p < 0.05), HH (n = 28; 62.2%; p < 0.05), or HH + HE (n = 1; 2.2%; p > 0.05) had been diagnosed and treated. Epidemiological, geographical, and clinical data concerning the occurrence and treatment protocols in these mandibular malformations were measured in the Polish study groups. RESULTS: Women more often suffered from these mandibular malformations (82-87%). The occurrence of the first symptoms was highest at the age of 13-15 years and was statistically significant for both sides (p < 0.05). The disorders were found earlier in young girls, therefore an early compensatory orthodontic treatment in some cases had been used with a limited degree of success (p > 0.05). All values of bone scintigraphy were significant (p < 0.001). CONCLUSIONS: A very fast growth with visible major asymmetry and enlarged condylar head should be an indication for condylectomy. Women's expectations from surgery and treatment are more demanding than men's, a fact that is connected with the predominance of females in the study group. Almost all possible treatment alternatives are not only related with the degree of skeletal deformity, but also with the patient's willingness to undergo any necessary treatment protocols, which in most cases involve more than one stage. Skeletal scintigraphy tests are an important factor in estimating bone growth and possible surgical approaches in these disorders.

Demographic features in Unilateral Condylar Hyperplasia: An overview of 309 asymmetric cases and presentation of an algorithm.

PURPOSE: Unilateral Condylar Hyperplasia (UCH) is an acquired deformity of the mandible, which can highly influence the symmetry of the face due to its progressive nature. It is caused by growth resembling pathology in one of the mandibular condyles. Definition as well as classification is subject to discussion. The aim of this study is to evaluate a large cohort of alleged UCH patients, and to describe the clinical characteristics, demographic features, classification and follow up. Secondly an algorithm is presented, in order to achieve uniformity in diagnosis and treatment. PATIENTS AND METHODS: From 1994 to 2014 a database of consecutive patients from 3 maxillofacial departments (Academic Medical Center, Amsterdam; VU Medical Center, Amsterdam and Spaarne Gasthuis, Haarlem) with suspected UCH was set up. Patients were referred by orthodontists, dentists, general practitioners or maxillofacial surgeons. Demographic features, bonescan outcomes, laterality, classification and follow-up were noted. Secondarily, all patients were retrospectively diagnosed by one surgeon (JWN), using available documentation. Missing data and follow-up were additionally retrieved from orthodontic offices. RESULTS: 394 asymmetric patients were evaluated. In 309 (78%) patients, the diagnosis UCH was justified and SPECT data were available. The mean age at presentation was 20.3 years (SD ± 7.7, range 9.0-54.5 years). In 48% of the patients, the bonescan was positive. 80% of these patients received surgical treatment, of which 62% were treated with a condylectomy only, 33% were treated with condylectomy plus additive corrective surgery, and 5% underwent corrective surgery only. Of the patient group without positive bonescan 42% of the patients received surgical treatment: 34% condylectomy only, 15% condylectomy plus additive corrective surgery, and 51% corrective surgery only. In total (N = 309) 96 (31%) patients underwent condylectomy as only surgical treatment and 124 (40%) patients received no surgical treatment at all. Treatment could be finalized with orthodontic treatment without further surgery in 64% and 41% respectively. 96 patients were subject to comparison of the classification as noted by the clinician and the author (JWN). In only 72% of the cases, the secondary screening was in agreement with the initial classification. CONCLUSION: Based on this study not all (active) UCH patients require corrective (orthognathic) surgery. A (transoral) partial condylectomy for active patients is recommended, with a postoperative remodeling period of 6 months with or without orthodontic treatment. Second stage correcting surgery may be necessary upon evaluation, using general orthognathic diagnostic and planning procedures. It appears difficult to classify patients reliably using the available clinical and radiological documentation. Objectivity and quantification in the diagnostic process is necessary: uniformity in documentation and parameters. The attached documentation form and UCH treatment algorithm is recommended.

Unilateral hemimandibular hyperactivity: Clinical features of a population of 128 patients.

PURPOSE: Facial asymmetries due to unilateral condylar hyperactivity are often a challenge both for maxillo-facial surgeons and for orthodontists; the current literature shows different opinions about aetiology, classification, treatment approach and timing. We made a retrospective study on patients suffering from unilateral condylar hyperactivity between 1997 and 2015 in our Department; clinical features and treatment options were grouped and compared with literature. METHODS: The descriptive analysis investigated variables like sex, age, side and direction of the asymmetry, condylar activity and type of intervention. RESULTS: The population was composed of 128 patients. The hemimandibular hyperactivity occurs equally in both sexes around the second decade, although the range of the first consultation goes from 7 to 49 y.o. The vertical hyperdevelopment group is almost equal to the horizontal. All the patients with horizontal hyperactivity showed negative scintigraphy and were treated with pre-surgical orthodontics and orthognathic surgery; patients with vertical hyperactivity and positive scintigraphy were treated with condylectomy and post-surgical orthodontics. CONCLUSION: In our group of patients, direction of the hyperactivity and results of the scintigraphy lead to treatment choice and timing. Further studies are necessary to explain why, in our group, all the patients with horizontal involvement are negative to scintigraphy.

High condylectomy versus proportional condylectomy: is secondary orthognathic surgery necessary?

The objective of this study was to assess the need for secondary orthognathic surgery in patients undergoing two different condylectomy protocols for active unilateral condylar hyperplasia (UCH). A retrospective cohort study evaluated UCH patients treated by condylectomy. Two groups were established: group 1 comprised those who had undergone a high condylectomy (5 mm removed) and group 2 comprised those who had undergone a proportional condylectomy (removing the difference observed between the measurements of the hyperplastic and the healthy side). Data analysis was done with the Levene test and t-test; a P-value of <0.05 indicated a statistically significant relationship. Forty-nine patients, with an average age of 19.83 years, were analyzed; 11 were included in group 1 and 38 in group 2. There was no statistical difference between the two groups with regard to age or sex (P=0.781). An average of 5.81 mm was removed in the high condylectomy group, while an average of 9.28 mm was removed in the proportional condylectomy group; this difference was statistically significant (P=0.042). Comparing the two groups, proportional condylectomy reduced the need for secondary orthognathic surgery (P<0.001). The proportional condylectomy can be used as the sole surgical treatment in cases of UCH, thus avoiding the need for secondary orthognathic surgery.