High condylectomy for the treatment of mandibular condylar hyperplasia: a systematic review of the literature

Accuracy of skeletal scintigraphy for the evaluation of mandibular growth disorders: a systematic review

Bone scans, reflecting blood flow and metabolic activity in a region of interest, are frequently used to evaluate mandibular growth disorders. Increased uptake is a non-specific finding and can occur as a result of multiple causes. The correlation between radioactive tracer uptake and growth activity has not been consistently demonstrated. The aim of this study was to assess the accuracy of planar skeletal scintigraphy (SS), single-photon emission computed tomography (SPECT), and SPECT with computed tomography (CT) images (SPECT/CT) in detecting abnormal mandibular growth activity compared to clinical and radiographic/tomographic methods (reference standard) and histologic findings. A systematic review was conducted following the PRISMA guidelines. Sensitivity, specificity, and accuracy were calculated for planar SS, SPECT, and SPECT/CT. Compared to the reference standard, SPECT/CT had the best diagnostic accuracy (76.5% sensitivity, 90.4% specificity, 83.2% accuracy), followed by planar SS (81.8% sensitivity, 84.5% specificity, 83.0% accuracy) and SPECT (77.7% sensitivity, 72.4% specificity, 74.5% accuracy). The results of this study indicate that SPECT/CT has the best clinical correlation, but the certainty of the evidence is low. The differences in sensitivity and specificity between the three index tests were not clinically significant. The three tests can be useful, with only a small difference in their diagnostic value. Histopathology was found not to be satisfactory as a reference standard.

Diagnostic accuracy of bone SPECT and SPECT/CT imaging in the diagnosis of unilateral condylar hyperplasia: A systematic review and meta-analysis

Imaging with bone scans plays an important role in the diagnostic path of patients with unilateral condylar hyperactivity or unilateral condylar hyperplasia (UCH). The aim of this study is to perform a systematic review of the diagnostic performance of the bone SPECT and SPECT/CT scan for the diagnosis of UCH. PubMed, SCOPUS and EMBASE were searched electronically to identify diagnostic accuracy studies that assessed the diagnostic value of bone SPECT and SPECT/CT for the diagnosis of UCH, Meta-analyses were performed with Metadisc 1.4 and 2.0. A total of 14 studies, with a total number of 887 patients, were included in the qualitative analysis and 11 studies qualified for meta-analyses. The pooled sensitivity and specificity for the SPECT scan were 0.814 (95 % CI: 0.639-0.915) and 0.774 (95 % CI: 0.655-0.861), for the SPECT/CT scan these were 0.818 (95 % CI: 0.749-0.874) and 0.901 (95 % CI: 0.840-0.945). The summary receiver operating characteristics of the SPECT scan showed an area under the curve of 0.847 (95 % CI: 0.722-0.972) and that of the SPECT/CT scan was 0.928 (95 % CI: 0.876-0.980). CONCLUSION: Both bone SPECT scan and SPECT/CT scan provide a high diagnostic accuracy for UCH. The added value of the SPECT/CT scan is questionable and given the potential disadvantages of the SPECT/CT scan, including the increased radiation dose and costs, the diagnostic modality of first choice in patients with UCH should be a SPECT scan.

Pediatric Temporomandibular Joint Pathology

Pediatric temporomandibular joint (TMJ) disorders represent a broad range of congenital and acquired diagnoses. Dentofacial deformities, including facial asymmetry, retrognathism, and malocclusion, commonly develop. Compared with adult TMJ conditions, pain and articular disc pathology are less common. Accurate diagnosis is paramount in planning and prognostication. Several specific considerations apply in preparation for skeletal correction, including timing in relation to disease progression and growth trajectory, expectation for postcorrection stability, reconstructive technique as it applies to expected durability and need for future revision, management of occlusion, and need for ancillary procedures to optimize correction. This article reviews common conditions and treatment considerations.

A proposed protocol for correlation between bone density in hemimandibular hyperplasia radiography and histopathological findings - A retrospective study

The role of low-dose computed tomography (LDCT) in surgical planning can be assessed based on the correlation among bone density (BD/HU), radiographic values, and the histopathological appearance of hyperplastic overgrowth in mandibular condyles (hemimandibular hyperplasia/osteochondroma). The aim of this study was to evaluate the correlation between LDCT indices of bone-density measurements in surgical planning and histopathological specimens. The patients incuded in this study underwent detailed radiological evaluation as preparation for further clinical procedures. Excised condyles were evaluated in terms of bone density index using LDCT, and then histopathologically to investigate the accuracy of surgical procedures and set the basis for future surgical planning. An index value between both condyles' bone densities represented the relative difference between the healthy condyle and the side with hemimandibular hyperplasia (HH). Patients with unilateral condylar hyperplasia (UCH) showed a statistical correlation between condyle heads with increased bone density (BD) and scintigraphic (SCI) values (p < 0.001). On the other hand, correlation between BD and histopathological studies alone was significant (p < 0.001). With the increase in BD measured in HU in UCH condyles, the overall value of fibrous cartilage layer thickness decreased (p < 0.001). Furthermore, histopathological evaluation indicated that increased bone density on the UCH side resulted in increased total thickness (p > 0.001). The proposed index measurements in the mandibular condyles based on LDCT/BD can be used to estimate the degree of required surgical resection. Results from LDCT radiographic studies correlate with histopathological specimens more than scintigraphy.

Condylar Hyperplasia: Case Report and Literature Review

Condylar hyperplasia is a rare pathology characterised by excessive bone growth that presents virtually unilaterally, resulting in facial asymmetry. The aetiology of this disorder is not well understood. This pathology has been reported to be a rare entity with very few cases being reported in the literature, mostly seen between 11 and 30 years of age, with males and females being equally affected and having no predominance to the left or right side. It has also been reported to be a self-limiting condition, that is, the active growth can cease at any point in time. We report two cases of unilateral condylar hyperplasia in 24- and 19-year-old male and female patients, where the first was treated by condylectomy and BSSO, and the latter was treated by high condylectomy and recontouring of the mandible.

Single photon emission computed tomography (SPECT) diagnostic accuracy in active unilateral condylar hyperplasia: Retrospective study

The aim of this study was to assess the diagnostic accuracy of single photon emission tomography (SPECT) in unilateral condylar hyperplasia (UCH). To this end, 3D morphometric changes of the mandibles in one year were assessed (T0 vs. T1) and compared over SPECT results in T1, in a sample of 40 patients. A contingency table was constructed based on these results for SPECT diagnostic accuracy evaluation, classifying patients as SPECT true-positive, true-negatives, false positives and false-negatives. Additionally, the morphometric analysis was used to describe the presentation of mandibular changes using principal component analysis (PCA) and non-parametric statistics. We obtained diagnostic accuracy results of sensitivity 81%, specificity 63%, positive predictor value (PPV) 59%, negative predictor value (NPV) 83% and accuracy 70%, showing that SPECT yields poor results regarding accuracy diagnostic performance. The morphometric analysis showed that individuals without progress of asymmetry and those with more progress differ particularly in a group of landmarks representing the mental region and the right mandibular body. Based on these landmarks, difference among the four SPECT-accuracy groups was statistically significant (p < 0.001), where the landmark showing the largest change within a year had a mean increase of 1.13 + 0.66 mm. Within the limitations of the study, it seems that SPECT alone is not suitable for making surgical decisions regarding condylectomy in active UCH. Follow up with morphological assessment methods are recommended for confirming an active UCH in combination with SPECT.

The learning curve of transoral condylectomy; a retrospective analysis of 100 consecutive cases of unilateral condylar hyperplasia

In this study, 100 consecutive scheduled transoral condylectomies for unilateral condylar hyperplasia were included. The safety and surgical performances were assessed, using the operating time, conversion rate and complication rate. The conversion rate learning curve was evaluated with a learning curve cumulative summation (LC-CUSUM). The total conversion rate was 8.0%. The LC-CUSUM for conversion signaled at the 53th procedure, indicating sufficient evidence had accumulated that the surgeon had achieved competence. For procedures 54-100, the conversion rate was 4.0%. The operating time for the transoral condylectomy was 41.5 ± 15.3 min; when a conversion was necessary, the operating time was 101.4 ± 28.3 min (p < 0.05). The estimated operating time in the post-learning phase was 37 min, this was reached after approximately 47 procedures. There was 1 major complication of a permanent inferior alveolar nerve hypoesthesia. The complication rate was not significantly decreased after the learning curve. Within the limitations of the study, it seems that transoral condylectomy for UCH is a safe procedure with several advantages over the traditional preauricular approach. Surgeons starting this procedure should be aware of the potential complications and of the learning curve of approximately 53 procedures.

Condylar resorption following mandibular advancement or bimaxillary osteotomies: A systematic review of systematic reviews

Several systematic reviews have been published on the effects of mandibular surgery on condylar remodeling without reaching a consensus. The purpose of this systematic review of systematic reviews was to assess the impact of mandibular advancement or bimaxillary surgeries on condylar resorption. A literature search, using several electronic databases, was carried out by two reviewers independently. Article preselection was based on titles and abstracts, and final article selection based on full-text analysis of preselected studies. After final study selection, the quality of studies was assessed using the AMSTAR 2 tool. A decision algorithm was subsequently established to choose the best body of evidence. From an initial yield of 1'848 articles, 23 systematic reviews were identified for further analysis, with ten studies being included in the final selection. Despite the generally low quality of the reviews, certain associations could be made: young patients, female patients, and those with a high mandibular plane angle are more prone to condylar resorption following mandibular advancement osteotomies, especially if anterior rotation of the mandible is performed during surgery. Patients undergoing bimaxillary surgery also appear to have a higher risk of developing condylar resorption. In conclusion, these results confirm the multi-factorial nature of condylar resorption, stressing the need for well-controlled prospective studies with long-term follow-up to clearly identify potential risk factors associated with orthognathic surgery.

Bone characteristics in condylar hyperplasia of the temporomandibular joint: a microcomputed tomography, histology, and Raman microspectrometry study

Unilateral condylar hyperplasia (UCH) of the temporomandibular joint is a progressive deformation of the mandibular condyle of unknown origin. UCH is characterized by excessive growth of the condylar head and neck, leading to an increase in size and volume. The aim of this study was to investigate the characteristics of the bone in patients with UCH using microcomputed tomography (micro-CT), histology, and Raman microspectroscopy. The mandibular condyles of six patients with UCH were analysed using micro-CT, histology, and Raman microspectrometry and imaging, and the results were compared with those obtained for a normal control subject. Three-dimensional micro-CT models revealed focal abnormalities of the bone microarchitecture, with foci of osteosclerosis. Histological sections showed that these foci included islands of calcified cartilage matrix with live chondrocytes. Raman analysis revealed that the cartilage matrix was more heavily calcified than the bone matrix and that the cartilage could be identified by the phenylalanine (PHE) band of its matrix, as well as by its glycosaminoglycan (GAG) content. The persistence of foci of live and active chondrocytes within the bone matrix is intriguing and appears to be pathognomonic of UCH. These new findings on UCH could help to determine its pathophysiology and thus prevent this disease, which can lead to major facial deformity.

Can electrocautery of the mandibular condyle effectively treat condylar hyperplasia?

This study aims to introduce and evaluate a novel technique to treat unilateral condylar hyperplasia (UCH) by electrocauterization of the mandibular condyle via an intraoral approach. Patients suffering from unilateral condylar hyperplasia (UCH) were included in this study. All patients underwent electrocauterization of the affected condyle. An intraoral incision on the anterior border of the mandibular ramus was made to expose the external surface of the ramus and access the anterior border of the condylar head. A hole was then drilled into the condyle and cauterization was performed; six patients also received orthognathic surgery during the procedure. Patients underwent careful clinical assessment and radiological evaluation including panoramic view, lateral and posteroanterior cephalometry, cone-beam computed tomography (CBCT) and scintigraphy to assess condylar growth for a period of 12-24 months. Ten patients (5 male and 5 female) with active UCH type 1B or 2A were included in this study with a mean age of 20.7 years (range, 18-21.7 years). At the 12-month postoperative assessment, clinical evaluation showed stable dental occlusion with no midline shift; scintigraphy showed persistently reduced cellular activity, and computed tomography scans revealed no degeneration in either of the condyles with complete healing of the drilled holes. Within the limitations of this study it seems that the proposed treatment approach might be an alternative to previously established protocols.

Precise Intraoral Condylectomy With the Guide of Three-Dimensional Printed Template in a Mandibular Condylar Hyperplasia Patient

PURPOSE

This study aimed to introduce an innovative method for mandibular condylectomy. A customized three-dimensional (3D) printed template is used to perform precise condylectomy in an intraoral approach.

METHODS

Condylectomy combined with orthognathic surgery was used for the treatment of facial asymmetry secondary to unilateral condylar hyperplasia. The customized 3D printed osteotomy guide was placed with an intraoral approach under endoscopy, in order to perform a precise condylectomy.

RESULT

With the customized 3D printed template, the condylectomy was performed more precisely, and the conventional extraoral incision was avoided. The osteotomy line was accurately transferred from the virtual surgical plan to the real surgery, which assured the precise resection.

CONCLUSIONS

The intraoral approach combined with a 3D printed template provides a novel solution to perform the condylectomy precisely.

Mandibular condylar remodeling characteristics after simultaneous condylectomy and orthognathic surgery

INTRODUCTION

The objectives of this study were to evaluate postsurgical condylar remodeling using a radiographical interpretation, quantify condylar volumetric asymmetry, and assess soft tissue symmetry after simultaneous unilateral high condylectomy and bimaxillary osteotomies.

METHODS

Sixteen patients diagnosed with unilateral condylar hyperplasia underwent unilateral high condylectomy and orthognathic surgery to correct skeletal and facial asymmetries. Cone-beam computed tomography scans were acquired before and 1-year after surgery. A radiographic consensus was evaluated for signs of reparative or degenerative changes. The condyles were mirrored and registered for assessment of volumetric and morphologic asymmetry. Soft tissue symmetry was evaluated by measurement of the distance of soft tissue pogonion from the skeletal midsagittal plane.

RESULTS

Patients who undergo unilateral high condylectomy and orthognathic surgery present radiographic signs suggestive of degenerative changes, including sclerosis, osteophytes, flattening, and erosion in both the surgical and nonsurgical condyles (P ≤0.01). There was an average volumetric improvement of 531.9 ± 662.3 mm³ 1-year postsurgery (P = 0.006). Soft tissue symmetry improved in all patients, with an average improvement of 65.8% (4.0 mm ± 2.6 mm, P ≤ 0.01). There was no correlation between the change in condylar volumetric asymmetry and the stability of the soft tissue correction.

CONCLUSIONS

High condylectomy for the correction of a skeletal asymmetry in patients with condylar hyperplasia successfully reduces the volumetric asymmetry between the condyles. Postsurgical dysmorphic remodeling and degenerative changes were noted in both the surgical and nonsurgical condyles. Despite remarkable changes and remaining joint asymmetry, the soft tissue correction is stable 1-year postsurgery.

Tissue engineered autologous cartilage-bone grafts for temporomandibular joint regeneration

Joint disorders can be detrimental to quality of life. There is an unmet need for precise functional reconstruction of native-like cartilage and bone tissues in the craniofacial space and particularly for the temporomandibular joint (TMJ). Current surgical methods suffer from lack of precision and comorbidities and frequently involve multiple operations. Studies have sought to improve craniofacial bone grafts without addressing the cartilage, which is essential to TMJ function. For the human-sized TMJ in the Yucatan minipig model, we engineered autologous, biologically, and anatomically matched cartilage-bone grafts for repairing the ramus-condyle unit (RCU), a geometrically intricate structure subjected to complex loading forces. Using image-guided micromilling, anatomically precise scaffolds were created from decellularized bone matrix and infused with autologous adipose-derived chondrogenic and osteogenic progenitor cells. The resulting constructs were cultured in a dual perfusion bioreactor for 5 weeks before implantation. Six months after implantation, the bioengineered RCUs maintained their predefined anatomical structure and regenerated full-thickness, stratified, and mechanically robust cartilage over the underlying bone, to a greater extent than either autologous bone-only engineered grafts or acellular scaffolds. Tracking of implanted cells and parallel bioreactor studies enabled additional insights into the progression of cartilage and bone regeneration. This study demonstrates the feasibility of TMJ regeneration using anatomically precise, autologous, living cartilage-bone grafts for functional, personalized total joint replacement. Inclusion of the adjacent tissues such as soft connective tissues and the TMJ disc could further extend the functional integration of engineered RCUs with the host.

The need for secondary orthognathic surgery after high condylectomy in patients with active unilateral condylar hyperplasia

The need for secondary orthognathic surgery (OS) after a high condylectomy (HC) in patients with active unilateral condylar hyperplasia was assessed in 25 patients, reviewing patient characteristics and treatment planning. At 6-12 months after HC, 13 patients (52%) required secondary OS. The amount of mandibular dental midline shift before the HC (P=0.037), and a dental crossbite that was present before the HC (P=0.017) were significantly associated with the need for secondary OS. Overall, the mandibular dental midline coincided with the facial midline in eight patients (32%) at 2 weeks after HC. In 16% of the patients, no additional OS was needed despite this being the initial treatment plan. Additionally, the initially planned type of secondary OS was modified in six other patients. Early HC in skeletally immature patients provided very good results, both aesthetic and functional, with only two of them needing supplementary OS at 6-12 months after HC. The HC remains a valuable treatment in patients with active unilateral condylar hyperplasia, as it can eliminate the need for secondary OS and is very well tolerated by most patients.

Concurrent High Condylectomy and Orthognathic Surgery for Treatment of Patients With Unilateral Condylar Hyperplasia

BACKGROUND

Facial asymmetry from unilateral condylar hyperplasia (UCH) may be definitively treated in the presence of active disease (with high condylectomy and concurrent orthognathic surgery) or after waiting for disease inactivity (orthognathic surgery alone). There is currently no consensus on the standard of care. In this study, we sought to compare functional and esthetic outcomes, as well as treatment duration, between these 2 management options.

METHODS

Patients who underwent treatment for UCH were identified through retrospective review. Pre- and postoperative 3-dimensional (3D) images were obtained. Short- and long-term operative outcomes of those treated during the active (group 1) were compared to those treated in the inactive phase (group 2). Total treatment time, operative time, and length of hospital stay were evaluated. Facial asymmetry was also assessed by laypersons using a Likert scale.

RESULTS

Fifteen patients (mean 25.6 years, range 14-56) were included: 6 in group 1 and 9 in group 2. All surgical outcomes were statistically independent of procedure type. Treatment time was significantly longer in the group 2 (P = 0.03). Both groups demonstrated significant improvement in facial asymmetry scores postoperatively with no significant difference in pre- or postoperative asymmetry between groups (P = 0.64).

CONCLUSIONS

In patients with active UCH, high condylectomy and orthognathic surgery is a procedure that restores facial symmetry and improves jaw function while halting mandibular growth. Good esthetic and functional outcomes, as well as reduced treatment time and disease burden, support the use of this treatment option for this population.

A new method for individual condylar osteotomy and repositioning guides used in patients with severe deformity secondary to condylar osteochondroma

Background

Mandibular condylar osteochondroma (OC) could lead to facial morphologic and functional disturbances, such as facial asymmetry, malocclusion, and temporomandibular joint dysfunction. However, after condylar OC resection, the inaccurate reposition of the neocondyle still needs to be solved. The purpose of this study was to explore the feasibility of the condylar osteotomy and repositioning guide to reposition the neocondyle in the treatment of patients with severe deformity secondary to condylar OC.

Results

Three patients with severe deformity secondary to OC of the mandibular condyle were enrolled in this study. With the aid of condylar osteotomy and repositioning guide, condylar OC resection and repositioning were carried out, and the accuracy and stability of these guides were evaluated. All patients healed uneventfully, and no facial nerve injury and condylar ankylosis occurred. Compared with the computerized tomography scans in centric relation before surgery and 3 days after surgery, the results showed that the facial symmetry was greatly improved in all the patients. Also, after the superimposition of the condylar segments before surgery and 3 days after surgery, the postoperative reconstructed condyles had a high degree of similarity to the reconstruction of the virtual surgical planning. Observed from the sagittal and coronal directions, the measurements of condylar positions were very close to those of virtual surgical planning. Moreover, it also showed stable results after a 1-year follow-up.

Conclusions

For patients with severe deformity secondary to condylar OC, condylar osteotomy, and repositioning guide was expected to provide a new option for the improvement of facial symmetry and occlusal relationship.

Piezoelectric Cutting Devices for Osteotomy in Temporomandibular Joint Condylectomy

Condylar hyperplasia is an alteration in mandibular growth that can cause facial asymmetry and occlusal changes that usually affect the aesthetics and function of patients. To date, condylectomy for its part remains a key part of the treatment. Although there are still controversies regarding the amount of bone to remove and the surgical approach, there are still other concerns, such as finding the benefit in terms of intraoperative safety and postoperative results with different cutting devices, including the use of piezoelectric, which is increasing its use in the maxillofacial field. This is why the main objective of this study is to compare the results found in medical records and databases of condylectomy procedures performed between 2017 and 2019 with different cutting devices.

Reference values of mandibular condyles metabolic activity: A study using 99m Tc-MDP single-photon emission computed tomography

OBJECTIVE

To assess the condylar bone metabolic activity in patients with temporomandibular joint health by measuring ^99m Tc-MDP uptake using a single-photon emission computed tomography (SPECT) to establish reference values of the uptake difference between condyles and the ratio with respect to the clivus.

SETTING AND SAMPLE POPULATION

Eighty consecutive patients of both sexes who were admitted to a Nuclear Medicine Centre between 2017 and 2019 were included in the study.

METHOD

This was an observational cross-sectional study in patients with SPECT indications to evaluate pathologies other than those of the temporomandibular joint. The values of the total and normalized counts in a fixed region of interest of five trans-axial slides were obtained to assess the percentage difference between the sides and the uptake ratio. The reference values are expressed as median and 5th and 95th percentiles.

RESULTS

The sample included 53 women (66.25%) and 27 men (33.75%) aged 15-55 years. The percentage of uptake difference between condyles was 5.04% (0.46-14.78) for men and 5.17% (0.27-13.21) for women (difference not significant, P = .9). The uptake difference was below 10% in 85% of the subjects (n = 68). The ratio values for total counts in women (0.87, 0.46-1.33) were significantly different (P = .0030) from those in men (1.08, 0.61-2.09). No significant correlation with age was found.

CONCLUSIONS

These new reference ranges are applicable to the diagnosis of unilateral and bilateral condylar hyperplasia.

Minimally invasive intraoral proportional condylectomy with a three-dimensionally printed cutting guide

The aim of this study was to describe the steps of a minimally invasive surgical technique used to perform a proportional intraoral condylectomy with a three-dimensionally (3D) printed cutting guide. The technique consists of two steps: virtual surgical planning and intraoral condylectomy. During virtual surgical planning, the mandibular ramus was measured bilaterally, the height of the proportional condylectomy was planned virtually, and a cutting guide was 3D printed. In the intraoral condylectomy, the mandibular condyle was approached intraorally, the 3D printed cutting guide was positioned in the sigmoid notch, and the proportional condylectomy was performed. The protocol reported in this technical note is the sum of knowledge acquired from a series of studies published previously by the authors, who have jointly developed a surgical technique that is both minimally invasive and accurate for the treatment of condylar hyperplasia.

Anatomical and Clinical Implications in Neocondyle Stability After a Condylectomy

: A condylectomy of the mandibular condyle is considered to be the treatment of choice in most cases of condylar head hyperactivity. The aim of the procedure is to remove the growth center of the mandible which is responsible for the mandibular enlargement and asymmetry. This surgical procedure has an impact on the condyle shape and position, but the restoration of mandibular movement and a stable joint position (namely, the proper alignment of the newly shaped condylar head within the condyle fossa) should also be considered important surgical outcomes. In this article, the authors present their own experience in performing condylectomies with an arthroplasty procedure and a special forced suturing technique (FST) in terms of achieving early, accurate mandibular movement and maintaining a stable condyle position in early and late outcomes.

MATERIALS AND METHODS

A modified high condylectomy with arthroplasty and FST results had been studied in anatomical, radiological, and clinical model.

RESULTS

Early findings after FST are promising. A slight improvement in lateral jaw movement was noted after condylectomy with arthroplasty (P < 0.05) both in early and late follow-up. Incisal opening, mandibular protrusion, and lateral movement were sustained. A stable condyle position within the fossa was achieved in each case of condylectomy with arthroplasty (P < 0.05).

CONCLUSIONS

The FST condylectomy and reattachment of the lateral pterygoid muscle in a new, wider position provided an improvement in lateral jaw movement as well as in incisal opening and mandibular protrusion in early follow-up examination compared to the presurgical values. It seems that the FST enabled a better new condylar head position in the glenoid fossa and improved early functional mandibular movement.

Unilateral Condylar Hyperplasia: Is Reactivation After a Long Latency Period of Inactivity Plausible?

Unilateral condylar hyperplasia (UCH) is characterized by an overgrowth of the mandibular condyle responsible for a facial and dental asymmetry associated with temporomandibular joint function and maxillary growth consequences. The diagnosis is based on a body of clinical, radiological and histological arguments. A 38 years old woman with a reactivation of UCH after a latency period of 16 years following an orthognathic surgery performed for facial asymmetry normalization is presented. She was addressed to our department for a facial progressive asymmetry relapse and dental prosthetic consequences.The radiological images and the planar scintigraphy combined with single-photon emission computed tomography scans showed an active left unilateral condylar hyperplasia. A left proportional condylectomy was performed.The case presented highlights the possibility for the UCH to be reactivated after a long period of latency, leading to a relapse of the occlusal and facial disorders and so advocates the need for first condylectomy or at least a long-term follow-up if condylectomy is not performed as a first-line treatment.

Correction of unilateral condylar hyperplasia and posterior open bite with proportional condylectomy and fixed orthodontic treatment

A 29-year-old female patient with unilateral condylar hyperplasia (UCH) of the left side presented with facial asymmetry, maxillary transverse occlusal plane (MXTOP) cant, posterior open bite, and Class III relationship. Treatment consisted of proportional condylectomy of the left condyle for management of UCH, and fixed orthodontic treatment with intrusion of the left maxillary molars to correct the MXTOP cant and remaining chin point deviation (CPD). Proportional condylectomy with a 14-mm resection of the left condylar head improved the CPD from 11.5 mm to 7.8 mm and resolved the posterior open bite on the left side. However, it produced a Class II relationship on the right and left sides, posterior open bite on the right side, and anterior open bite. Fixed orthodontic treatment with 1.8-mm intrusion of the left maxillary molars using miniscrews corrected the MXTOP cant from 3.5 mm to 1.7 mm, reduced the remaining CPD from 7.8 mm to 3.7 mm, produced counterclockwise rotation of the mandible, and resolved the posterior open bite on the right side and the anterior open bite. After 16 months of total treatment, normal overbite/overjet and Class I relationship were obtained. Treatment results were well maintained after 5 years of retention. For the correction of UCH, it is important to determine the amount of condylar head resection and accurately simulate the correction of CPD and MXTOP cant through intrusion of the maxillary molars.

Condilectomia alta associada à discopexia, com mini-âncoras, no tratamento da hiperplasia condilar: relato de caso

Introdução: A hiperplasia condilar (HC) é uma patologia rara caracterizada por crescimento não neoplásico que afeta a morfologia do côndilo mandibular com deformação progressiva. Dentre os sinais mais comuns se encontram a assimetria facial e mandibular, além de possíveisalterações oclusais como mordida aberta ipsilateral e transversal contralateral. Objetivo: O objetivo do estudo foi demonstrar a eficácia terapêutica da condilectomia alta associada à discopexia, com mini-âncoras, no tratamento da hiperplasia condilar. Relato de caso: Paciente de 24 anos de idade, apresentando assimetria facial, déficit e incompetência funcional mastigatória, mordida aberta posterior ipsilateral e mordida cruzada posterior contralateral. A proposta terapêutica escolhida foi o tratamento cirúrgico com condilectomia alta e discopexia com âncora para estabilização do disco articular, através de acesso endaural para o côndilo afetado com tamponamento auricular. Foi realizado infiltração com ácido hialurônico intra-articular após sutura da cápsula articular e sutura por planos para sutura da pele. Conclusão: A condilectomia alta preveniu a progressão da deformidade facial, minimizando as sequelas funcionais e estéticas, o que visa a favorecer o tratamento das deformidades faciais através de correção ortognática em segundo momento cirúrgico.

Comparação de diferentes planejamentos em cirurgia ortognática para tratamento de assimetrias faciais: relato de casos

Introdução: a cirurgia ortognática envolve a correção de desarmonias funcionais e estéticas. A hiperplasia condilar (HC) resulta em crescimento mandibular acentuado, provocando assimetria facial. Para obter previsibilidade e sucesso nos resultados, é imprescindível planejar. Objetivo: descrever e comparar métodos de planejamento e resultados pós-operatórios por meio de relato de três pacientes com assimetria facial. Relato de caso: foram avaliados 03 casos (casos A, B e C) orto-cirúrgicos de pacientes adultos jovens, com média de idade de 22 anos, portadores de má oclusão esquelética de Classe III, com assimetria facial resultante de HC inativa. Esses foram submetidos a análise facial e a dois métodos de planejamento em cirurgia ortognática (convencional e virtual). O caso A foi planejado por meio de imagens bidimensionais (2D) e sequência cirúrgica iniciada pela maxila. O caso B foi planejado por imagens 2D associado ao recurso de simulação em protótipo. E o caso C, planejado exclusivamente em imagens tridimensionais (3D) e simulação virtual. Os casos B e C utilizaram sequência cirúrgica iniciada pela mandíbula. Foi utilizado o software Dolphin Imaging® em todos os planejamentos. Os planejamentos foram transferidos para os procedimentos cirúrgicos por auxílio dos guias em resina acrílica e estereolitografia. Os pacientes dos casos relatados foram avaliados periodicamente no pós-operatório e estavam satisfeitos com os resultados. Conclusão: os planejamentos demonstraram previsibilidade e viabilidade para assimetrias faciais, pois os resultados foram satisfatórios. Houve uma tendência de melhores resultados quando a prototipagem, imagens 3D e sequência operatória iniciada pela mandíbula foram utilizadas no planejamento.

Morphometric Characterization of Asymmetric Mandibles Due to Condylar Hyperactivity

PURPOSE

Mandibular asymmetry related to condylar hyperactivity (CH) presents a complex set of morphologic features that pose challenges for its correction. Using state-of-the-art morphometric techniques, this report provides a detailed and hierarchical description of the features present in CH-related asymmetric mandibles and offers new knowledge for the surgical treatment of CH.

MATERIALS AND METHODS

Sixty patients were included in the sample. Thirty had CH-related asymmetric mandibles and the other 30 had clinically symmetric mandibles. Twenty-eight 3-dimensional landmarks were placed on computed tomographically based reconstructions of each participant's mandible and analyzed using geometric morphometric analysis for the quantitative and qualitative comparison of their morphologic features.

RESULTS

All 60 participants exhibited asymmetry. However, those with CH exhibited a broad range of shapes and even shared several morphologic features with the controls. Mainly the ramus and then the body were the main contributors of the differences between groups.

CONCLUSIONS

There is considerable overlap of anatomic features characterizing symmetric and asymmetric mandibles; based on shape alone, the 2 groups can be easily misclassified. The ramus and body of the affected side in CH-related asymmetric mandibles were the main contributors to asymmetry of the structure. The chin, a usual diagnostic structure, did not greatly contribute to the structural asymmetry of the mandible.

Part II: Temporomandibular Joint (TMJ)-Regeneration, Degeneration, and Adaptation

PURPOSE OF REVIEW

Elucidate temporomandibular joint (TMJ) development and pathophysiology relative to regeneration, degeneration, and adaption.

RECENT FINDINGS

The pharyngeal arch produces a highly conserved stomatognathic system that supports airway and masticatory function. An induced subperiosteal layer of fibrocartilage cushions TMJ functional and parafunctional loads. If the fibrocartilage disc is present, a fractured mandibular condyle (MC) regenerates near the eminence of the fossa via a blastema emanating from the medial periosteal surface of the ramus. TMJ degenerative joint disease (DJD) is a relatively painless osteoarthrosis, resulting in extensive sclerosis, disc destruction, and lytic lesions. Facial form and symmetry may be affected, but the residual bone is vital because distraction continues to lengthen the MC with anabolic bone modeling. Extensive TMJ adaptive, healing, and regenerative potential maintains optimal, life support functions over a lifetime. Unique aspects of TMJ development, function, and pathophysiology may be useful for innovative management of other joints.