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Heliyon Oct 2023With the acceleration of the aging process of the population, the number of edentulous patients continuously increased. Edentulism induces the loss of occlusal... (Review)
Review
BACKGROUND
With the acceleration of the aging process of the population, the number of edentulous patients continuously increased. Edentulism induces the loss of occlusal relationship and cause adverse effects on the stomatognathic system. Temporomandibular joint (TMJ), as a significant component of this system, may also be affected by edentulism in the process of supporting mandibular movement.
PURPOSE
Provide a comprehensive review of the structure and function of TMJ in the edentulous population, as well as the prevalence of temporomandibular joint disorder (TMD) in edentulous group.
STUDY SELECTION
An electronic search was conducted on articles prior to December 2022 to filter all papers relevant to the structure and function of TMJ in edentulous population. The internet databases (PubMed, Cochrane Library, Embase) were searched using various combinations of keywords for "edentulism" or "edentulous" and "TMJ" or "TMD".
RESULTS
Firstly, 522 articles were selected from the internet database, and finally, a total of 44 articles met the inclusion and exclusion criteria. The research content of these articles mainly focuses on the structure and function of TMJ in edentulous patients, as well as the clinical signs and symptoms of TMD.
CONCLUSIONS
Edentulous arch induces the loss of occlusal relationship, which may lead to degenerative changes of TMJ components consisting of changes in morphology and bone mass density of condyle, articular fossa, and articular eminence. In addition, the condyle could be shifted backward and upward, and displacement of the articular disc may occur after dentition loss. And the condyle and the articular disc may be guided back to the normal position after effective prosthodontic treatment. But the conclusions of the study on the function of TMJ and the prevalence of TMD in edentulous people are inconsistent. The condition of TMJ, especially the position of condyle-fossa and the symptoms and signs of TMD should not be ignored. If necessary, radiographic examinations should be performed.
PubMed: 37829806
DOI: 10.1016/j.heliyon.2023.e20307 -
Medicina Oral, Patologia Oral Y Cirugia... May 2024Assess the correlation between the position of the third molar (M3) and fractures of the mandibular angle and condyle using panoramic radiographs to offer valuable data...
BACKGROUND
Assess the correlation between the position of the third molar (M3) and fractures of the mandibular angle and condyle using panoramic radiographs to offer valuable data references for oral clinical research.
MATERIAL AND METHODS
A retrospective cross-sectional study was undertaken, involving the collection of 409 cases of mandibular fracture in the Yanbian University Hospital. The case records and panoramic radiographs of mandibular angle fracture (78 cases) and condylar fracture (106 cases) were evaluated.
RESULTS
In the comparative analysis between the mandibular angle fracture group and the condylar fracture group, statistical significance was observed in the variables of M3 existence (P = 0.002), eruption of M3 from the alveolar cavity (P = 0.003), P&G position classification (P = 0.001), deep impactions (Classes IC, IIC, IIIB, and IIIC) (P < 0.001), and the presence of impacted M3 in both groups (P < 0.001).Regarding M3 roots, the mandibular angle fracture group exhibited the highest prevalence of multiple roots at 75.4%, surpassing the 64.6% observed in the condylar fracture group. The prevalence of proximal angles in the mandibular angle group and the condyle group was the highest, accounting for 64.6% and 61.5%, respectively. The percentage of M3 in the two groups was 80% and 43.1%, respectively, with a significant difference (P < 0.001).
CONCLUSIONS
Impacted mandibular third molars (M3) elevate the risk of mandibular angle fractures, while their absence or normal eruption reduces this risk and protects against condylar process fractures. The fracture risk is influenced by the M3's position: P&G Class II and Class B impactions, where M3s emerge partially from the alveolar bone, are significantly associated with mandibular angle fractures. In contrast, the absence of M3 or its placement in P&G Class I and Class A positions tends to correlate with a higher incidence of condylar process fractures.
PubMed: 38794934
DOI: 10.4317/medoral.26604 -
Journal of the Formosan Medical... Sep 2023Auriculocondylar syndrome (ARCND) is a genetic and rare craniofacial condition caused by abnormal development of the first and second pharyngeal arches during the... (Review)
Review
Auriculocondylar syndrome (ARCND) is a genetic and rare craniofacial condition caused by abnormal development of the first and second pharyngeal arches during the embryonic stage and is characterized by peculiar auricular malformations (question mark ears), mandibular condyle hypoplasia, micrognathia and other less-frequent features. GNAI3, PLCB4 and EDN1 have been identified as pathogenic genes in this syndrome so far, all of which are implicated in the EDN1-EDNRA signal pathway. Therefore, ARCND is genetically classified as ARCND1, ARCND2 and ARCND3 based on the mutations in GNAI3, PLCB4 and EDN1, respectively. ARCND is inherited in an autosomal dominant or recessive mode with significant intra- and interfamilial phenotypic variation and incomplete penetrance, rendering its diagnosis difficult and therapies individualized. To raise clinicians' awareness of the rare syndrome, we focused on the currently known pathogenesis, pathogenic genes, clinical manifestations and surgical therapies in this review.
Topics: Humans; Phenotype; Ear Diseases; Ear; Mutation
PubMed: 37208246
DOI: 10.1016/j.jfma.2023.04.024 -
Clinical Oral Investigations Jan 2024To evaluate the temporomandibular joint (TMJ), condylar and mandibular movements in obstructive sleep apnea (OSA) patients treated with mandibular advancement device...
OBJECTIVES
To evaluate the temporomandibular joint (TMJ), condylar and mandibular movements in obstructive sleep apnea (OSA) patients treated with mandibular advancement device (MAD) and to identify the influence of these anatomic factors on upper airway (UA) volume and polysomnographic outcomes after treatment.
MATERIALS AND METHODS
Twenty OSA patients were prospectively treated with MAD. Clinical examinations, cone-beam computed tomography, and polysomnography were performed before MAD treatment and after achieving therapeutic protrusion. Polysomnographic variables and three-dimensional measurements of the TMJ, mandible, and upper airway were statistically analyzed.
RESULTS
Condylar rotation, anterior translation, and anterior mandibular displacement were directly correlated with total UA volume, while vertical mandibular translation was inversely correlated with the volume of the inferior oropharynx. MAD treatment resulted in an increase in the volume and area of the superior oropharynx. There was no statistically significant correlation between condylar rotation and translation and polysomnographic variables. With MAD, there was a significant increase in vertical dimension, changes in condylar position (rotation and translation), and mandibular displacement. The central and medial lengths of the articular eminence were inversely correlated with condylar rotation and translation, respectively. The lateral length of the eminence was directly correlated with condylar translation, and the lateral height was directly correlated with condylar rotation and translation.
CONCLUSION
Condylar and mandibular movements influenced UA volume. The articular eminence played a role in the amount of condylar rotation and translation.
CLINICAL RELEVANCE
Individualized anatomical evaluation of the TMJ proves to be important in the therapy of OSA with MAD.
Topics: Humans; Occlusal Splints; Mandible; Sleep Apnea, Obstructive; Temporomandibular Joint; Cone-Beam Computed Tomography; Mandibular Advancement; Treatment Outcome
PubMed: 38286954
DOI: 10.1007/s00784-024-05513-9 -
Cureus Nov 2023This study aimed to examine the impact of demographic variables on mandibular condyle morphology, a critical factor in orthodontic treatment and maxillofacial surgery....
OBJECTIVES
This study aimed to examine the impact of demographic variables on mandibular condyle morphology, a critical factor in orthodontic treatment and maxillofacial surgery. The investigation focuses on the relationship between gender, age, and skeletal class with the morphological dimensions of the condyle, utilizing panoramic radiography as a diagnostic tool.
METHODOLOGY
A retrospective analysis was conducted on 150 panoramic radiographs from individuals stratified into six groups according to gender and skeletal class. Skeletal classes were determined using Steiner and McNamara cephalometry. The Kodak Carestream software (Rochester, NY: Carestream Health) was employed to measure condylar height, width, and morphology. Statistical evaluations included ANOVA, correlation assessments, and multivariate binary logistic regression to discern the differences and associations among the variables studied.
RESULTS
The findings revealed notable differences in condylar dimensions between genders across different skeletal classes, with males typically presenting larger condylar dimensions than females. The data also showed a moderate positive correlation between condyle height and width. Round-shaped condyles were the most common form found, with significant gender differences observed in certain skeletal classes. Additionally, logistic regression analysis identified significant associations between gender, age, and condylar width and shape.
CONCLUSIONS
The study concludes that demographic factors, such as gender and age, significantly affect mandibular condyle morphology. These factors should be carefully considered in clinical evaluations using panoramic radiography to enhance the precision of diagnoses and the effectiveness of subsequent orthodontic and maxillofacial treatments. The results provide valuable insights for healthcare professionals in regions where more advanced imaging techniques may not be readily available.
PubMed: 38116346
DOI: 10.7759/cureus.49043 -
Maxillofacial Plastic and... Aug 2023This study aimed to compare the skeletal structures between mandibular prognathism and retrognathism among patients with facial asymmetry.
BACKGROUND
This study aimed to compare the skeletal structures between mandibular prognathism and retrognathism among patients with facial asymmetry.
RESULTS
Patients who had mandibular asymmetry with retrognathism (Group A) in The Netherlands were compared with those with deviated mandibular prognathism (Group B) in Korea. All the data were obtained from 3D-reformatted cone-beam computed tomography images from each institute. The right and left condylar heads were located more posteriorly, inferiorly, and medially in Group B than in Group A. The deviated side of Group A and the contralateral side of Group B showed similar condylar width and height, ramus-proper height, and ramus height. Interestingly, there were no inter-group differences in the ramus-proper heights. Asymmetric mandibular body length was the most significantly correlated with chin asymmetry in retrognathic asymmetry patients whereas asymmetric elongation of condylar process was the most important factor for chin asymmetry in deviated mandibular prognathism.
CONCLUSION
Considering the 3D positional difference of gonion and large individual variations of frontal ramal inclination, significant structural deformation in deviated mandibular prognathism need to be considered in asymmetric prognathism patients. Therefore, Individually planned surgical procedures that also correct the malpositioning of the mandibular ramus are recommended especially in patients with asymmetric prognathism.
PubMed: 37556073
DOI: 10.1186/s40902-023-00393-7 -
Journal of Otolaryngology - Head & Neck... Jul 2023Resection of the mandible and temporomandibular joint (TMJ) without formal reconstruction is a devastating condition that negatively affects all aspects of the patient's...
INTRODUCTION
Resection of the mandible and temporomandibular joint (TMJ) without formal reconstruction is a devastating condition that negatively affects all aspects of the patient's life. We have approached the reconstruction of mandibular defects that include the condyle with simultaneous reconstruction with a vascularized free fibular flap (FFF) using Surgical Design and Simulation (SDS) and alloplastic TMJ prosthesis. The objective of this study is to report the functional and quality of life (QOL) outcomes in a cohort of patients that had undergone our reconstructive protocol.
METHODS
This was a prospective case series of adult patients that underwent mandibular reconstruction with FFF and alloplastic TMJ prosthesis at the our center. Pre-operative and post-operative maximum inter-incisal opening (MIO) measurements were collected, and patients completed a QOL questionnaire (EORTC QLQ-H&N35) during those perioperative visits.
RESULTS
Six patients were included in the study. The median patient age was 53 years. Heat map analysis of the QOL questionnaire revealed that patients reported a positive clinically significant change in the domains of pain, teeth, mouth opening, dry mouth, sticky saliva, and senses (relative change of 2.0, 3.3, 3.3, 2.0, 2.0, and 1.0 respectively). There were no negative clinically significant changes. There was a median perioperative MIO increase of 15.0 mm, and this was statistically significant (p = 0.027).
CONCLUSIONS
This study highlights the complexities involved in mandibular reconstruction with involvement of the TMJ. Based on our findings, patients can obtain an acceptable QOL and good function following simultaneous reconstruction with FFF employing SDS and an alloplastic TMJ prosthesis.
Topics: Adult; Humans; Middle Aged; Mandibular Reconstruction; Free Tissue Flaps; Quality of Life; Joint Prosthesis; Temporomandibular Joint; Treatment Outcome
PubMed: 37400904
DOI: 10.1186/s40463-023-00639-4