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Journal of Oral Rehabilitation Jul 2022The recent review article by Zonnenberg, Türp and Greene 'Centric relation critically revisited - What are the clinical implications'? opens an important debate by...
The recent review article by Zonnenberg, Türp and Greene 'Centric relation critically revisited - What are the clinical implications'? opens an important debate by addressing topics of central relevance in Dentistry, namely the relationship between occlusion and the condyle-to-glenoid-fossa position, and the need for diagnostic assessment and therapeutic alteration of the condylar position in orthodontic patients. Zonnenberg, Türp and Greene concluded that the mandibular condyle is correctly situated in most orthodontic patients. Thus, in their view, orthodontists can disregard this aspect during treatment, and rely on the plastic properties of the masticatory supporting structures, while aiming at finishing the cases in a good occlusal relationship. We think that this approach fails to consider that biological variation of the stomatognathic structures can also be pathological and that, as dental occlusion determines condylar relative position within the glenoid fossa, changes in the occlusion are likely to alter the original condylar-to-glenoid-fossa relation. Hence, we claim that whenever the occlusal relationship must be changed, the clinician should carefully monitor the condyle position and the mandibular function to prevent possible iatrogenic effects. To advance the discourse on the topic, we invite Zonnenberg, Türp and Greene to clarify their definition of 'average patient' and their interpretation of 'full-mouth orthodontic and orthognathic treatment', their understanding of 'biologically acceptable condylar relationship', their justification of maximum intercuspation as reference position, the extent to which they think it is safe to rely on the TMJ resilience, and finally their alternative to centric relation in the treatment of patients needing condylar repositioning.
Topics: Centric Relation; Dental Occlusion, Centric; Humans; Mandibular Condyle; Temporomandibular Joint
PubMed: 35377510
DOI: 10.1111/joor.13329 -
Folia Morphologica 2022Panoramic radiographs are the most common radiographic tool used by the dental clinicians to evaluate teeth, mandible and other related structures of the jaws....
BACKGROUND
Panoramic radiographs are the most common radiographic tool used by the dental clinicians to evaluate teeth, mandible and other related structures of the jaws. Mandibular condyle is an important anatomical landmark for facial growth, expressed in an upward and backward direction. The presentation of mandibular condyle differs widely among different group of ages and individuals.
MATERIALS AND METHODS
The retrospective cross-sectional study was conducted from November 2018 to March 2019 at Dow International Dental College Karachi that includes radiographic evaluation of 500 mandibular condyles. All retrievable orthopantomograms were obtained and data were extracted regarding age, gender and condylar morphology.
RESULTS
The morphological appearances of mandibular condyle have great variation among different age groups and subjects. Normally, we recognise five basic shapes i.e. oval, bird beak, crooked finger, diamond and mixed. Out of 250 pair of condylar heads that were evaluated, 50% were oval, 40% bird beak, 4.8% crooked finger and diamond 4.8%.
CONCLUSIONS
All four morphological types of mandibular condyles were observed and the oval shape condyles were most prevalent among both genders and all age groups. In future studies, the inclusion of other parameters and large sample size may provide unique information.
Topics: Cross-Sectional Studies; Female; Humans; Male; Mandible; Mandibular Condyle; Radiography, Panoramic; Retrospective Studies
PubMed: 34018177
DOI: 10.5603/FM.a2021.0049 -
Medicina Oral, Patologia Oral Y Cirugia... Nov 2012To evaluate the etiopathogenesis, clinical features, therapeutic options, and surgical approaches for removal of ectopic third molars in the mandibular condyle. (Review)
Review
OBJECTIVES
To evaluate the etiopathogenesis, clinical features, therapeutic options, and surgical approaches for removal of ectopic third molars in the mandibular condyle.
STUDY DESIGN
MEDLINE search of articles published on ectopic third molars in the mandibular condyle from 1980 to 2011. 14 well-documented clinical cases from the literature were evaluated together with a new clinical case provided by the authors, representing a sample of 15 patients.
RESULTS
We found a mean age at diagnosis of 48.6 years and a higher prevalence in women. In 14 patients, associated radiolucent lesions were diagnosed on radiographic studies and confirmed histopathologically as odontogenic cysts. Clinical symptoms were pain and swelling in the jaw or preauricular region, trismus, difficulty chewing, cutaneous fistula and temporomandibular joint dysfunction. Treatment included conservative management in one case and in the other cases, surgical removal by intra- or extraoral approaches, the latter being the most common approach carried out. In most reported cases, serious complications were not outlined.
CONCLUSIONS
The etiopathogenic theory involving odontogenic cysts in the displacement of third molars to the mandibular condyle seems to be the most relevant. They must be removed if they cause symptoms or are associated with cystic pathology. The surgical route must be planned according to the location and position of the ectopic third molar, and the possible morbidity associated with surgery.
Topics: Adult; Aged; Female; Humans; Male; Mandibular Condyle; Middle Aged; Molar, Third; Tooth Eruption, Ectopic
PubMed: 22926463
DOI: 10.4317/medoral.17864 -
European Journal of Orthodontics Feb 2009Deviations in the growth of the mandibular condyle can affect both the functional occlusion and the aesthetic appearance of the face. The reasons for these growth... (Review)
Review
Deviations in the growth of the mandibular condyle can affect both the functional occlusion and the aesthetic appearance of the face. The reasons for these growth deviations are numerous and often entail complex sequences of malfunction at the cellular level. The aim of this review is to summarize recent progress in the understanding of pathological alterations occurring during childhood and adolescence that affect the temporomandibular joint (TMJ) and, hence, result in disorders of mandibular growth. Pathological conditions taken into account are subdivided into (1) congenital malformations with associated growth disorders, (2) primary growth disorders, and (3) acquired diseases or trauma with associated growth disorders. Among the congenital malformations, hemifacial microsomia (HFM) appears to be the principal syndrome entailing severe growth disturbances, whereas growth abnormalities occurring in conjunction with other craniofacial dysplasias seem far less prominent than could be anticipated based on their often disfiguring nature. Hemimandibular hyperplasia and elongation undoubtedly constitute the most obscure conditions that are associated with prominent, often unilateral, abnormalities of condylar, and mandibular growth. Finally, disturbances of mandibular growth as a result of juvenile idiopathic arthritis (JIA) and condylar fractures seem to be direct consequences of inflammatory and/or mechanical damage to the condylar cartilage.
Topics: Adolescent; Arthritis, Juvenile; Cartilage Diseases; Cartilage, Articular; Child; Craniofacial Abnormalities; Facial Asymmetry; Humans; Hyperplasia; Mandible; Mandibular Condyle; Mandibular Diseases; Mandibular Fractures; Temporomandibular Joint Disorders
PubMed: 19164410
DOI: 10.1093/ejo/cjn117 -
Turkish Journal of Medical Sciences Oct 2022To investigate morphological features of the mandibular condyle and its association with anterior temporomandibular disc displacement on sagittal oblique MRI plane.
BACKGROUND
To investigate morphological features of the mandibular condyle and its association with anterior temporomandibular disc displacement on sagittal oblique MRI plane.
METHODS
One hundred and twenty patients with temporomandibular MRI examination were retrospectively involved in the study. Patients aged less than 18 years and those with severe osteoarthritis, posterior disk displacement, tumor, abscess, history of a rheumatic disease, facial trauma, and motion artifacts on images were excluded. Three radiologists evaluated all images in consensus. Temporomandibular disc locations were classified as normal, anteriorly displaced with reduction (ADr), and anteriorly displaced without reduction (ADwr) on sagittal oblique T1-weighted images. Condylar shapes were classified as flat, rounded, and angled, and condyle anteroposterior width (c-APW) was measured on these images in closed-mouth position.
RESULTS
Ninety six discs were in normal position (40%), 70 discs were ADr (29%), and 74 discs were ADwr (31%). Eighty-four condyles were flat (35%), 100 condyles were rounded (42%), and 56 condyles were angled (23%). Mean c-APW was 7 mm in normal joints, 5.9 mm in ADr, and 5.8 mm in ADwr joints, and it was smaller in joints with anterior disc displacement (p < 0.001). In normal joints, flat and rounded type condylar shape was more common and almost equally prevalent (44% and 43%); however, rounded type was more common among ADr (%47) and angled type was more common among ADwr joints (36%) (p = 0.008). Patients with anterior disc displacement were significantly younger from normal cases and anterior disc displacement was more common among female sex.
DISCUSSION
Mandibular condyle shape alterations and condyle size on sagittal oblique MRI plane are associated with anterior disc displacement. Angled shape was more common among ADwr joints. Joints with anterior disc displacement had smaller c-APW than normal joints.
Topics: Humans; Female; Temporomandibular Joint Disc; Temporomandibular Joint Disorders; Joint Dislocations; Retrospective Studies; Mandibular Condyle
PubMed: 36422509
DOI: 10.55730/1300-0144.5501 -
Dental and Medical Problems 2021The objective of rehabilitation after the treatment of a mandibular condyle fracture is to retrieve the effortless, symmetrical opening of the jaws with the preservation...
BACKGROUND
The objective of rehabilitation after the treatment of a mandibular condyle fracture is to retrieve the effortless, symmetrical opening of the jaws with the preservation of appropriate movements to the sides, and appropriate occlusion without a sense of tension in the mastication muscles or pain sensations.
OBJECTIVES
The aim of the article was to establish the conditions of the rehabilitation of temporomandibular joint (TMJ) after the surgical treatment of a fractured condyle.
MATERIAL AND METHODS
The research featured 46 of patients treated surgically between January 2, 2017 and December 30, 2017. The open reduction and rigid internal fixation (ORIF) was the method mainly applied. Rehabilitation with the use of the Delphi technique was implemented in each patient. The assessment of the mastication organ was mostly performed at 3 and 6 weeks since the beginning of rehabilitation. In every patient, the interincisal distance was measured; in chosen cases, the range and trajectory of the condyle movements, and the trajectory of the secant point during jaw opening were defined with the use of the Zebris® JMA device.
RESULTS
In 45 patients, a full reposition and immobilization of 52 bone fragments of fractured mandibular condyles was obtained. The displacement of the midline of the mandible in occlusion or an incorrect occlusion contact determined the decision on the application of intermaxillary fixation in 8 patients for a period of 2 weeks. The minimal jaw opening of 40 mm was achieved in 41 patients after 6 weeks of rehabilitation. In 5 of the rest of the patients, rehabilitation had to be continued. The reassessment of the X-ray images and additional computed tomography (CT) diagnosis in three-dimensional (3D) reconstruction in those patients revealed the possible causes of difficulties in the restoration of the stomatognathic system functions – the injuries of the muscles or ligaments connected with the joint.
CONCLUSIONS
The extension of radiological diagnostics with a CT examination may improve the assessment of the restored TMJ function after the surgical treatment of a fractured mandibular condyle.
Topics: Fracture Fixation, Internal; Humans; Mandible; Mandibular Condyle; Mandibular Fractures; Treatment Outcome
PubMed: 33847468
DOI: 10.17219/dmp/128092 -
Medicina Oral, Patologia Oral Y Cirugia... Nov 2018Bifid mandibular condyle (BMC) constitutes an extremely rare disorder characterized by a duplication of the head of the mandibular condyle. Its prevalence ranges from...
BACKGROUND
Bifid mandibular condyle (BMC) constitutes an extremely rare disorder characterized by a duplication of the head of the mandibular condyle. Its prevalence ranges from 0.31% to 1.82% in the published literature.
OBJECTIVES
The primary objective was to describe the main etiological, clinical and radiological characteristics of patients with BMCs and the existent treatment options. The secondary objective was to simultaneously include the characteristics of two new cases of BMC.
MATERIAL AND METHODS
An electronic search in Pubmed (MEDLINE), Scopus and The Cochrane Library was carried out by two independent reviewers until April 2018. Prospective or retrospective cohort studies, case series and case reports describing clinical and/or radiological characteristics of patients with BMC were included. Registered variables were demographic, etiological factors, diagnostic exam, clinical characteristics and treatment options. The results from the articles selected were organized in a Table along with the characteristics of two new cases of BMC provided by the authors.
RESULTS
From a total of 431 articles found in the initial search, 68 articles were finally included. This systematic review included 216 patients and 270 BMC with an average age of 30.6 (SD=14.7) years and a women:men ratio of 1.4:1. Mediolateral condylar orientation was the most prevalent position (80.1%). Among cases with known etiology, 40.8% of cases had a history of traumatism, while 55.9% did not present any relevant medical background. Half of the symptomatic cases had history of trauma. The most common symptoms were hypomobility (22.7%), arthralgia (18.1%), articular noise (17.2%) and ankylosis (17.6%). Active monitoring and manufacturing an occlusal splint were the most frequent treatment options.
CONCLUSIONS
BMC may have congenital or traumatic etiology. Hypomobility and arthralgia are the most frequent symptoms and treatment options are often conservative.
Topics: Congenital Abnormalities; Female; Humans; Male; Mandibular Condyle; Middle Aged
PubMed: 30341271
DOI: 10.4317/medoral.22681 -
Journal of Oral and Maxillofacial... Jan 2019Accurate description of the temporomandibular size and shape (morphometry) is critical for clinical diagnosis and surgical planning and the design and development of...
PURPOSE
Accurate description of the temporomandibular size and shape (morphometry) is critical for clinical diagnosis and surgical planning and the design and development of regenerative scaffolds and prosthetic devices and to model the temporomandibular loading environment. The study objective was to determine the 3-dimensional morphometry of the temporomandibular joint (TMJ) condyle and articular disc using cone-beam computed tomography (CBCT), magnetic resonance imaging (MRI), and physical measurements of the same joints using a repeated measures design and to determine the effect of the measurement technique on temporomandibular size and shape.
MATERIALS AND METHODS
Human cadaveric heads underwent a multistep protocol to acquire physiologically meaningful measurements of the condyle and disc. The heads first underwent CBCT scanning, and solid models were automatically generated. The superficial soft tissues were dissected, and intact TMJs were excised and underwent MRI scanning, with solid models generated after manual segmentation. After MRI, the intact joints were dissected, and physical measurements of the condyle and articular disc were performed. The CBCT-based model measurements, MRI-based model measurements, and physical measurements were standardized, and a repeated measures study design was used to determine the effect of the measurement technique on the morphometric parameters.
RESULTS
Multivariate general linear mixed effects models showed significant effects for measurement technique for condylar morphometric outcomes (P < .001) and articular disc morphometric outcomes (P < .001). The physical measurements after dissection were larger than either the CBCT-based or MRI-based measurements. Differences in imaging-based morphometric parameters followed a complex relationship between imaging modality resolution and contrast between tissue types.
CONCLUSIONS
Physical measurements after dissection are still considered the reference standard. However, owing to their inaccessibility in vivo, understanding how the imaging technique affects the temporomandibular size and shape is critical toward the development of high-fidelity solid models to be used in the design and development of regenerative scaffolds, surgical planning, prosthetic devices, and anatomic investigations.
Topics: Humans; Magnetic Resonance Imaging; Mandibular Condyle; Spiral Cone-Beam Computed Tomography; Temporomandibular Joint; Temporomandibular Joint Disorders
PubMed: 30076808
DOI: 10.1016/j.joms.2018.06.175 -
International Journal of Molecular... Dec 2019The temporomandibular joint (TMJ) is an intricate structure composed of the mandibular condyle, articular disc, and glenoid fossa in the temporal bone. Apical condylar... (Review)
Review
The temporomandibular joint (TMJ) is an intricate structure composed of the mandibular condyle, articular disc, and glenoid fossa in the temporal bone. Apical condylar cartilage is classified as a secondary cartilage, is fibrocartilaginous in nature, and is structurally distinct from growth plate and articular cartilage in long bones. Condylar cartilage is organized in distinct cellular layers that include a superficial layer that produces lubricants, a polymorphic/progenitor layer that contains stem/progenitor cells, and underlying layers of flattened and hypertrophic chondrocytes. Uniquely, progenitor cells reside near the articular surface, proliferate, undergo chondrogenesis, and mature into hypertrophic chondrocytes. During the past decades, there has been a growing interest in the molecular mechanisms by which the TMJ develops and acquires its unique structural and functional features. Indian hedgehog (Ihh), which regulates skeletal development including synovial joint formation, also plays pivotal roles in TMJ development and postnatal maintenance. This review provides a description of the many important recent advances in Hedgehog (Hh) signaling in TMJ biology. These include studies that used conventional approaches and those that analyzed the phenotype of tissue-specific mouse mutants lacking Ihh or associated molecules. The recent advances in understanding the molecular mechanism regulating TMJ development are impressive and these findings will have major implications for future translational medicine tools to repair and regenerate TMJ congenital anomalies and acquired diseases, such as degenerative damage in TMJ osteoarthritic conditions.
Topics: Animals; Cartilage, Articular; Cell Differentiation; Chondrogenesis; Hedgehog Proteins; Humans; Mandibular Condyle; Mice; Osteoarthritis; Signal Transduction; Temporomandibular Joint Disc
PubMed: 31847127
DOI: 10.3390/ijms20246300 -
Dento Maxillo Facial Radiology Sep 2022Three-dimensional radiological anatomic characteristics of condyle trabeculae was obtained quantitatively based on a volume-of-interest (VOI) analysis.
OBJECTIVES
Three-dimensional radiological anatomic characteristics of condyle trabeculae was obtained quantitatively based on a volume-of-interest (VOI) analysis.
METHODS
Nine human mandibular condyle specimens were scanned by micro-computed tomography (micro-CT). A total of 34 VOIs were selected from each condyle specimen, which were divided into six layers and four parts to analyze the morphological characteristics of trabeculae based on cylindrical VOIs with a diameter and height of 2 mm. One-way analysis of variance was used to compare the regional differences of morphological parameters among each layer and part.
RESULTS
Values for bone mineral density, bone volume/total volume, trabecular thickness, and trabecular bone number were greater in the anterior part compared with the posterior part; and the lateral part was larger than the medial part in the first, second, and third layers, while the medial part was larger in the fourth and fifth layers; these values in the first and sixth layers were much larger, while those in the third and fourth layers were smaller. Bone surface area/bone volume, trabecular spacing, and trabecular bone pattern factor were larger in the posterior part than in the anterior part; and the lateral part was larger than the medial part in the fourth and fifth layers, while the medial part was larger in the first and second layers.
CONCLUSIONS
The morphological distribution of VOIs was anisotropic within trabecular bone of human mandibular condyles. The upper and lower ends of trabecular bone were much more compact, with higher bone density, trabecular thickness, and trabecular number than in the middle layers.
Topics: Anisotropy; Bone Density; Cancellous Bone; Humans; Mandibular Condyle; X-Ray Microtomography
PubMed: 35731780
DOI: 10.1259/dmfr.20220138