Articular Eminence Inclination Research Articles

Characteristics of the Occlusal Plane Associated with Unilateral and Bilateral Articular Eminence Inclination: A Cross-Sectional CBCT Study.

The characteristics of the temporomandibular joint (TMJ) are essential in orthodontic and prosthetic treatments. Previous studies have suggested an association between articular eminence inclinations (AEI) and occlusal plane characteristics using radiographs, but no bilateral analysis has been conducted using cone beam computed tomography (CBCT). Objective: This study aimed to investigate the specific characteristics of the occlusal plane inclinations associated with unilateral and bilateral AEI using CBCT. Methods: We conducted a cross-sectional study to evaluate 200 temporomandibular joints (TMJs) from 100 records obtained at the orthodontic department. We evaluated the association between the AEI, and occlusal plane characteristics like the cant of the occlusal angle, occlusal plane angles, inclination of the upper incisor to the Frankfort plane and palatal plane using both bivariate and multivariate analyses both unilaterally and bilaterally. Results: Our findings suggested statistically significant associations (p < 0.050) between AEI (bilateral) and occlusal inclination parameters, including the cant of the occlusal plane (Coef. -0.38; 95%CI -0.70:-0.06; p = 0.017), occlusal plane angle (Coef. -0.39; 95%CI -0.740:-0.05; p = 0.024), and position of the upper incisor relative to the palatal plane (Coef. -0.34; 95%CI -0.63:-0.06; p = 0.016). Conclusion: This study suggests an association between dental inclinations and AEI, which reflects the anatomical characteristics of TMJ and its related dental structures.

COMPARATIVE EVALUATION OF ARTICULAR EMINENCE INCLINATION AND MANDIBULAR CONDYLE FRACTAL DIMENSIONS OF DIFFERENT TYPES OF EDENTULISMFarklı

Objective: To estimate if a correlation exists between edentulousness type and changes in the articular eminence inclination (AEI) and to compare these data with the trabecular structure of the mandibular condyle using fractal analysis. Material and Methods: A total of 88 panoramic radiographs and 176 temporomandibular joints (TMJ) of four groups (n=22), which were divided according to dental status, were evaluated according to the AEI and fractal dimensions (FD) of the temporomandibular joints by one radiologist using the ImageJ (National Institutes of Health. MD, USA) program, retrospectively. The conformity of the values with normal distribution was evaluated using the Shapiro-Wilk test. A one- way ANOVA model was used while comparing the edentation status and relationships between FDs, and AEI measurements were assessed using Pearson’s correlation analysis. The level of statistical significance was taken as p

Comparative Evaluation of Temporomandibular Joint Parameters in Unilateral and Bilateral Cleft Lip and Palate Patients Using Cone-Beam CT: Focus on Growing vs. Non-Growing Subjects.

Morphological differences in the temporomandibular joint (TMJ) are crucial for the treatment of patients with cleft lip and palate (CLP). This study aims to evaluate and compare the TMJ parameters in patients with unilateral and bilateral CLP across growing and non-growing age groups using cone-beam computed tomography (CBCT). CBCT records from 57 patients (23 males and 34 females) aged 6-50 years with a diagnosed unilateral or bilateral CLP were analyzed. Patients were categorized into four groups: growing unilateral (UGCLP), growing bilateral (BGCLP), non-growing unilateral (UNGCLP), and non-growing bilateral (BNGCLP). Measurements of TMJ parameters, including the mandibular fossa, articular eminence inclination, joint spaces, and roof thickness of the glenoid fossa, were conducted using CBCT images. Significant differences were observed in the anterior joint space (AJS) and the roof of the glenoid fossa (RGF) between growing and non-growing unilateral cleft patients. Additionally, significant discrepancies were found in the articular eminence angle when comparing the cleft and non-cleft sides within the unilateral growing group. No significant differences were observed in TMJ parameters between the right and left sides among bilateral cleft patients. The study highlights distinct TMJ morphological differences between growing and non-growing patients with CLP, emphasizing the importance of age-specific considerations in the treatment planning and growth monitoring of these patients.

The correlation analysis between incisal guidance angle and occlusal plane angles and temporomandibular joint morphology.

The correlations between the incisal guidance angle (IGA) and occlusal plane angles and temporomandibular joint (TMJ) morphology were investigated in adults with skeletal Class II division II malocclusion. CBCT images of 37 patients were analyzed. It included 19 cases of skeletal Class II division II malocclusion with low angle (study group) and 18 cases of skeletal Class I average angle (control group). The Invivo Dental 5 software was employed to acquire the data of the incisal guidance angle (IGA), occlusal plane angle (FH-OP), anterior occlusal plane angle (FH-AOP) and the TMJ measurement items. The results of IGA, FH-AOP angle and FH-OP angle showed the study group > the control group (P < 0.05). There were statistically difference in the condylar mediolateral diameters, articular eminence inclination and height, and posterior joint spaces between two groups. No differences were revealed in the condylar anteroposterior diameters, the condylar inclination angle, condylar head width and height, condylar length, glenoid fossa depth and width between two groups. In the study group, IGA showed a moderate correlation with FH-AOP, a weak correlation with FH-OP and condylar mediolateral diameters. Meanwhile, there was a correlation between FH-AOP, FH-OP, and TMJ indicators. The IGA was not only related to FH-AOP and FH-OP, but also to the condylar mediolateral diameters. In addition, there was a correlation between the occlusal plane angles and TMJ morphology in skeletal Class II division II low angle malocclusion. For patients with skeletal Class II division II low angle malocclusion, adjusting the IGA and the occlusal plane angles could improve the esthetic appearance of the anterior teeth, occlusal function, and TMJ morphology.

Modifications of the articular eminence inclination in association with the loss of occlusal support in the molar area. A cone-beam computed tomography study.

The articular eminence (AE) is part of the temporal component of the temporomandibular joint (TMJ). The inclination of the AE (AEI) has an important role in TMJ biodynamics, influencing the path of movement of the disc-condyle complex. Although AEI values might change due to tooth loss, little is known about what effect could have the loss of occlusal support in the molar area on AE morphology. AEI was measured on cone-beam computed tomography (CBCT) images of 41 patients (82 TMJs) with or without occlusal support in the molar region. The patients included in this study were divided into four groups: (1) patients with maintained occlusal support in the molar areas on both sides (right and left side) (MM); (2) patients with loss of occlusal support in the molar areas on both sides (right and left side) (LL); (3) patients with loss of occlusal support in the molar area only on the right side, but with maintained occlusal support on the left molar area (LM); (4) patients with loss of occlusal support in the molar area only on the left side, but with maintained occlusal support in the right molar area (ML). AEI values were higher in the TMJs on the side with maintained occlusal support in the molar area (M) than the AEI values measured in TMJs from the side with loss of occlusal support in the molar area (L). AEI values on the right side were higher in the MM patients in comparison to the AEI values on the right side of LL patients. The loss of occlusal support in the molar areas changes the mandibular biodynamics, which might be reflected in the morphological changes at the AE level, where it might cause flattening of the articular slope predominantly on the right side.

Comparison of temporomandibular joint osseous components in unilateral and bilateral cleft lip and palate patients and normal controls: A CBCT study

ObjectiveThe objective of this study was to conduct a comparative analysis of the components of the temporomandibular joint in individuals with unilateral, bilateral cleft lip and palate (CLP), and in healthy individuals, utilizing cone beam computed tomography (CBCT) images. Method and materialThe present study employed a cross-sectional design and recruited participants aged 18 to 30 years. The participants were categorized into three groups: a control group consisting of 36 individuals without any cleft, a group of 35 patients with unilateral cleft lip and palate (UCLP), and a group of 15 patients with bilateral cleft lip and palate (BCLP). The analysis of CBCT images encompassed the examination of condylar height and angulation, glenoid fossa height and width, articular eminence inclination, as well as joint spaces across all three groups. The Kruskal-Wallis and Mann-Whitney tests were employed to ascertain the significant differences among the three groups. ResultsThe UCLP and BCLP groups demonstrated a statistically significant reduction in condylar height and articular eminence inclination in comparison to the control group. Furthermore, a significant difference in the width of the glenoid fossa was seen between the group with clefts and the control group. ConclusionThe CBCT images showed significant differences in several aspects of the temporomandibular joint, including condylar height, articular eminence inclination, and glenoid fossa width, in individuals with cleft palate. These abnormalities can contribute to the development of temporomandibular joint diseases. Therefore, recognizing these distinctions can help prevent further deterioration and progression of temporomandibular disorders (TMD) in CLP patients.

Comparison of temporomandibular joints in relation to ages and vertical facial types in skeletal class II female patients: a multiple-cross-sectional study

BackgroundThe temporomandibular joint (TMJ) is closely related to the dynamic balance and stability of mandibular function and orthodontic treatment. Skeletal class II female patients are thought to be at high risk for TMJ disease. The relationship between the TMJ and craniofacial structures is still controversial. This study compared the morphology and position of the TMJ in skeletal class II adolescents and adults with various vertical facial types using cone-beam computed tomography (CBCT).Materials and methodsA total of 117 skeletal class II patients were divided into three groups according to the FH-GoGn angle (hypodivergent, normodivergent and hyperdivergent), with 40 class I normodivergent patients serving as controls. Each group contained two age subgroups (adolescents: 11–14 years old, adults: 18–35 years old). The size (condylar length, height, long and short axis diameter, glenoid fossa width and depth) and shape (condylar neck inclination, condylar head angle and long axis angle, articular eminence inclination) of the condyle and fossa, joint space (anterior, superior, posterior, mesial and lateral), and position of the fossa (vertical, transverse, and anteroposterior distance) and condyle were measured and compared using CBCT.ResultsClass II hypodivergent patients exhibited the greatest condylar length, height, and long- and short-axis diameter; steepest articular eminence; deepest fossa depth; largest superior, mesial and lateral joint spaces; and highest fossa position in both age groups. The manifestations of class II hyperdivergent patients were mostly the opposite. In adults, except for the condylar long axis angle, the measurements of the condyle increased differently among skeletal patterns, while the measurements of the fossa decreased, as the joint spaces and fossa position remained approximately stable compared with those in adolescents.ConclusionThe vertical skeletal pattern, rather than the class II sagittal skeletal pattern, may be the main factor affecting the morphology and position of the TMJ. Attention should be given to the TMJ area in hyperdivergent patients with a relatively poor-fit condyle-fossa relationship. The changes in the TMJ with age were mainly morphological rather than positional and varied with skeletal pattern.

Effect of Dentulous and Edentulous Status on Articular Eminence Inclination of Temporomandibular Joint in Adult Patients – A Cross-sectional Orthopantomogram Study

Introduction: The inclination of articular eminence (AE) varies across population. The AE dictates the path of condylar movement as well as the degree of rotation of the disc over the condyle. Mechanical conditions caused by aging and influenced by the loss of teeth might have some effect on remodulation and reshaping of the AE. Aim and Objective: The aim of the study was to compare the inclination of AE of temporomandibular joint (TMJ) in dentulous and edentulous elderly patients. Materials and Methods: Orthopantomogram scans fulfilling the inclusion criteria for dentulous and edentulous patients were included in the study. Patients with age range of 50–70 years were divided into two groups: Group A (dentulous) and Group B (edentulous). The inclination of AE was measured and compared. Results and Conclusion: Mean AE Inclination (AEI) value in dentulous and edentulous was 36.56 degrees and 30.16 degrees, respectively. The AEI was significantly increased in dentulous patients as compared to edentulous patients. The results of the current study are of great relevance as it suggests that maintenance of dentition is necessary to retain the proper physiologic function of TMJ.

The prevalence of temporomandibular disorder and temporomandibular morphology among diverse chronotype profiles

ABSTRACT This study investigates the influence of chronotype on the prevalence of temporomandibular joint disorders (TMD) and the morphology of temporomandibular joint (TMJ). According to the Morningness–Eveningness Questionnaire-Self-Assessment, the participants were divided into morning group (n = 30), intermediate group (n = 83), and evening group (n = 30). Thirty participants were randomly selected from the intermediate group for subsequent examination and measurements. The morphology of TMJs was investigated using questionnaire and clinical examination form in Diagnostic Criteria for Temporomandibular Disorder. Meanwhile, the morphological results of TMJs were measured from cone-beam computed tomography images. The prevalence rate of TMD in the morning group (23%) was significantly lower than that in the intermediate group (56.7%), while there was no difference between the evening (53.4%) and intermediate groups. As to morphological measurements, there was no significant difference among three groups in mediolateral width of condylar process, anteroposterior width of condylar process, radius of condyle, medial joint space, lateral joint space, condylar stress angle, horizontal condylar inclination, width of glenoid fossa, depth of glenoid fossa, and posterior joint space, while there was a significant difference in horizontal condylar angle (p = 0.00490), articular eminence inclination (p < .0001), anterior joint space (p = 0.0163), and superior joint space (p = 0.0004). The morphology of TMJ in the morning group was better than that in the evening and intermediate groups. An association was found between TMD prevalence, temporomandibular morphology, and chronotype.

Investigation of Condyle Positions in Patients with Temporomandibular Joint Disorder by Cone-Beam Computed Tomography

Objective: The condylar position refers to the location of the mandibular condyle within the glenoid fossa when the teeth are in maximum intercuspal, and it is an important indicator of the temporomandibular joint (TMJ) function. This study aimed to assess the condylar position of the TMJ in patients with TMJ disorder using cone-beam computed tomography (CBCT). Methods: The present study utilized CBCT to evaluate the condylar position of the TMJ in a sample of 56 patients. Among them, 28 patients were asymptomatic while the remaining 28 had been diagnosed with TMJ disease. To evaluate the presence of TMJ disorders, the Research Diagnostic Criteria for Temporomandibular Disorders was employed. This diagnostic tool is widely used in clinical and research settings to assess TMJ-related pain and dysfunction. Results: The agreement was excellent, according to the intra-observer and inter-observer correlation values obtained. There was no statistically significant difference between the two groups in terms of age and gender distribution. The results showed that the anterior and posterior joint spaces were significantly higher in the symptomatic group compared to the asymptomatic group. However, there was no statistically significant difference between the two groups in terms of superior joint space and articular eminence inclination values. Gender did not create a significant difference in any parameter. Conclusion: The results of this study emphasize that CBCT images have an important role in detecting significant changes in condyle position in patients with TMJ disorders. However, further large-scale studies are necessary to validate and enhance the findings.

Cone-beam computed tomographic characteristics in degenerative temporomandibular joint disease patients with chewing side preference

This study is aimed at assessing the Cone-beam computed tomographic (CBCT) characteristics of temporomandibular joints (TMJ) in degenerative temporomandibular joint disease (DJD) patients with chewing side preference (CSP). CBCT images of 98 patients with DJD (67 with CSP and 31 without CSP) and 22 asymptomatic participants without DJD were measured retrospectively to compare the osteoarthritic changes and the morphology of TMJ. Quantitative analysis of the TMJ radiographic images was performed to present a comparison between the three inter-group groups and between the two sides of the joints. The frequencies of the articular flattening and surface erosion occur more often in the preferred side joints of DJD patients with CSP than the contralateral side. In addition, the horizontal angle of condyle, the depth of glenoid fossa (DGF), and the inclination of articular eminence (IAE) were larger in DJD patients with CSP than that in asymptomatic participants (p<0.05). Also, the condylar anteroposterior dimension of preferred side joints was significantly less than that of non-preferred side (p=0.026), while the width of condyles (p=0.041) and IAE (p=0.045) was greater. DJD patients with CSP appear to have a higher prevalence of osteoarthritic changes, with the morphological changes such as flat condyle, deep glenoid fossa, and steep articular eminence, which might be considered the characteristic imaging features. This study found that CSP is a predisposing factor for the development of DJD, and attention should be paid to the existence of CSP in DJD patients during the clinical practice.

Comparison of accuracy of protrusive condylar guidance registration by two interocclusal recording materials in edentulous patients.

During complete denture fabrication making Interocclusal records plays an integral role to obtain the condylar guidance value. The study was conducted to compare the protrusive condylar guidance registration by two interocclusal recording materials-Quick setting plaster and Luxabite®(bisacrylic composite) in semi adjustable articulator for completely edentulous patients. Maxillary and Mandibular casts of the completely edentulous patients were mounted in Hanau®Wide Vue articulator. The Quick setting plaster and Luxabite®(bisacrylic composite) was used as interocclusal recording materials to program the protrusive condylar guidance angles in the articulators. The protrusive condylar guidance values registered in the articulator for the different interocclusal records were tabulated and statistically analyzed.. The mean protrusive condylar guidance values registered in the articulator was compared with two parameters obtained from the radiographic tracings -- the protrusive condylar path angle obtained with Quick setting plaster and Luxabite with the inclination of articular eminence to the Frankfort horizontal plane. From the study it was concluded that the Luxabite®(bisacrylic composite) material demonstrated better reproducibility of protrusive condylar guidance registration.than the Quick setting plaster.

Assessment of The Effects of Edentulousness on Temporomandibular Components by Using Cone Beam Computed Tomography

Objective: The aim of this study is to evaluate the effects of edentulousness on the temporomandibular joint using cone beam computed tomography (CBCT). Methods: In this study, CBCT images were evaluated in a total of 48 patients (24 dentulous, 24 edentulous). Ninety-six temporomandibular joint CBCT images were examined. Eminence inclination, condyle head widths and joint space were measured and statistically compared between the edentulous and dentulous groups. Results: The articular eminence inclination value the mediolateral width of the condyle and the anteroposterior width of the condyle were found significantly higher in the dentulous group than in the edentulous group. There was no significant difference between the dentulous and edentulous groups in terms of the anterior, superior and posterior joint space. Conclusion: In the edentulous patients, the articular eminence inclination value, mediolateral and anteroposterior widths of the condyle head were found to lower in comparison to the dentulous patients

Evaluation of condyle-fossa relationships in skeletal Class I malocclusion with variable degrees of deep overbite and open bite

ABSTRACT Objective To compare the temporomandibular joint (TMJ) position and shape between skeletal Class I subjects with different degrees of deep overbite or open bite and unaffected peers. Methods Cone beam computed tomography (CBCT) images of 90 participants, equally divided into deep bite, open bite, and control groups (DBG, OBG, and CG, respectively), were analyzed. The DBG and OBG were further subdivided into three subgroups based on the severity. Linear and angular measurements were used to determine the positional and morphological characteristics of the TMJ. Results DBG showed significantly larger superior joint space, anterior inclination of the condyle, and articular eminence inclination than CG and OBG. The severity of deep bite and open bite significantly influenced the TMJ position and morphology. Conclusion In severe deep overbite and open bite cases, there were considerable alterations in TMJ components, most likely as a result of functional demands.

Edentulism and Costen’s syndrome revision. A literature review

The aim of this review is to raise the awareness of the clinician concerning the morphological changes in the oral cavity, the temporomandibular joint, and the vestibulocochlear apparatus that take place due to chronic untreated edentulism, partial or complete, and their possible correlation to the diagnosis of Costen‘s syndrome. The physiological state of the temporomandibulolar joint and its components such as the condyle, articular eminence and capsular ligaments are going to be analyzed in correlation with the orofacial and ves- tibulocochlear changes that take place in the edentulous state. For this purpose, special focus is going to be attributed to the condylar inclination, articular eminence inclination flattening and neuroreceptor and osseous auditory conduction impairment due to the corresponding loss of vertical dimention of occlusion. It is mentioned that restoration of the vertical dimension is able to revert the symptoms and lead to complete healing after treatment with dentures. Fact that orientates into the suggestion of furthermore scientific research combining the skills between the ENT specialist and the dentist.

Evaluation of temporomandibular joint components and mandibular bone structure in ankylosing spondylitis patients

The study aimed to investigate the mandible and temporomandibular joint (TMJ) in patients with ankylosing spondylitis (AS) who had no signs or symptoms of TMJ-related disease and compare them with a control group. In total, 128 panoramic radiographs (63 patients with AS, 65 controls) were evaluated. Fractal analysis was conducted on the mandibular condyle (ROI1), angle of the mandible (ROI2), and the area adjacent to the mental foramen (ROI3). Articular eminence inclination (AEI) values were measured. Klemetti index (KI) evaluation of the mandibular cortex was also performed. Fractal dimension (FD) values were significantly lower in the patients with AS than the controls in ROI1 and ROI2 (P=.001), but there were no significant differences between groups for FD in ROI3, AEI, or KI (P ≥ .09). No significant differences were found in any parameters between patients with AS with different disease durations (P ≥ .06). Patients with AS displayed significantly lower FD values in condyles and the angle of the mandible and slightly lower AEI values; therefore, they should be examined routinely for TMJ disorders. Clinicians should be aware of the possibility of secondary osteoporosis in patients with AS and consider its probable effects on the mandible.

Comparative Analysis of Condylar Guidance Angle Obtained by Protrusive Interocclusal Records and Radiographic Methods in Edentulous Patients: An In Vivo Study

Abstract Purpose To compare between values of condylar inclination obtained by protrusive interocclusal records using extraoral Gothic arch tracing with cone-beam computed tomography (CBCT) scan, and cephalometric and panoramic radiographs in edentulous patients. Materials and Methods Horizontal condylar guidance angle (HCGA) was measured using the extraoral Gothic arch tracing, CBCT, lateral cephalogram, and orthopantomogram (OPG) in 20 patients aged between 40 and 75 years. HCGAs were determined clinically using protrusive interocclusal records and semi-adjustable articulator after extraoral Gothic arch tracing. Radiographically, Frankfort horizontal plane was marked and a straight line joining the superior-most point and the inferior-most point of posterior slope of the articular eminence (AE) was drawn till the two lines met at an intersection. The angle at this intersection depicted the AE inclination and the angle was measured. Statistical analysis was done using analysis of variance test, multiple comparison was done using Tukey test, and the Pearson correlation coefficient was compiled for different study parameters. Result A significant difference in condylar guidance was observed among different methods (p-value &lt; 0.05), and significant positive correlations were observed among condylar guidance measured using distinct parameters. Conclusion It was concluded that horizontal condylar guidance (HCG) values with the radiographic technique were higher than the clinical method. It was observed that mean HCG values were higher by 6.4 degrees in CBCT, 6.7 degrees in OPG, and 9.9 degrees in lateral cephalogram as compared with the clinical value. It was also observed that there was a variation of condylar guidance up to 5 degrees between right and left sides.

&lt;strong&gt;The increasing risk of temporomandibular disorder and articular eminence inclination due to tooth loss&lt;/strong&gt;

ABSTRACTIntroduction: Tooth loss leads to increased biomechanical pressure in the temporomandibular joint due to changes in the functional movement pattern of the jaw, resulting in joint structure damage specifically change of the articular eminence inclination (AEI) angle, which is one of the increased risks of the temporomandibular disorder (TMD). This study aimed to analyze the relationship between the number and quadrants of tooth loss on TMD and the AEI. Methods: It was descriptive-analytic study using a cross sectional design. The study was done in Universitas Sumatera Utara (USU) Dental hospital, conducted questionnaires and panoramic radiographic on 42 subjects aged over 18-64 years with tooth loss. Data analyzed used Chi-square analysis. Results: The prevalence of TMD on the ≥3 tooth loss group by 82.6% and the four-quadrant group by 93.8%. The prevalence of change in the AEI on the ≥3 tooth loss group was 34.8% on the flat right side, while on the left side of 26.1% was flat, and 13% was steep. Based on the number of quadrants tooth loss, the highest was on the four-quadrant group by 50% on flat right side, and on the three-quadrant group was 25% flat, 25% steep on the left side. There was a significant relationship between the number of tooth loss (p=0.023), the number of tooth loss quadrants, and TMD (p=0.016). There was no relationship between the number of tooth loss and the AEI, except for the number of tooth loss quadrants and the AEI on the right side with a significant result (p=0.017). Conclusion: There was relationship between the number of tooth loss, the number of tooth loss quadrants, and TMD and there was no relationship between the number of tooth loss and the AEI, except for the number of tooth loss quadrants and the AEI on the right side.Keywords: Edentulous; tooth loss; temporomandibular disorder; inclination of articular eminence.

Age-related variations in position and morphology of the temporomandibular joint in individuals with anterior openbite and crossbite: a multi-cross-sectional comparative study

BackgroundThis study aimed to compare the age-related positional and morphological characteristics of the temporomandibular joint (TMJ) between individuals with anterior openbite or crossbite and controls.MethodsThis multi-cross-sectional comparative study analysed cone-beam computed tomography images of 750 participants, equally divided into the openbite, crossbite, and control groups (OBG, CBG, and CG, respectively). Each group was further divided into five subgroups (8–11 years, 12–15 years, 16–19 years, 20–24 years, and 25–30 years). Measurements of the TMJ included the position of the condyles in their respective fossae and morphology of the condyles and fossae. Data were submitted to statistical analysis. The study adhered to the STROBE Statement checklist for reporting of cross-sectional studies.ResultsCondyles were positioned more posteriorly with increasing age in all groups, and the condylar position was more posterior in the OBG than in the CBG. The articular eminence inclination increased with age in all the groups. There were significant differences in the articular eminence inclination among the three major groups at the age of > 15 years, and the condylar path was flatter in the CBG than in the OBG.ConclusionsAge-related morphological and positional characteristics of the TMJ differed considerably among OBG, CBG and CG. Contrary to CBG, OBG was found to have relatively posterior condylar position and steeper condylar path.

Effects of conventional complete dentures and implant-supported overdentures on alveolar ridge height and mandibular bone structure: 2-year and 6-year follow-up study.

The aim of this study was to compare the changes in mandibular bone structure in edentulous patients who were rehabilitated with conventional complete dentures (CCD) and implant supported overdentures (ISO), by evaluating alveolar bone loss (ABL), panoramic mandibular index (PMI), mandibular cortical width (MCW), gonion index (GI), antegonial index (AI), and articular eminence inclination (AEI). Panoramic radiographs of 63 edentulous patients using CCD, 63 edentulous patients using ISO, and 126 patients without tooth loss were evaluated. Edentulous patients had a 2-year and 6-year follow-up panoramic radiograph image. ABL (anterior, premolar, and molar regions), MCW, PMI, AI, GI, and AEI were measured in each patient. Variation between measurements was analyzed using repeated measures ANOVA test and post hoc Tukey test. Both edentulous groups showed significantly lower mean than without tooth lost group in all measures (p < 0.000). ISO group showed significantly lower mean ABL than CCD group in anterior (p = 0.000), right premolar (p = 0.005), left premolar (p = 0.005), right molar (p < 0.000), and left premolar (p < 0.000) regions in short term. ISO group showed significantly lower mean ABL than CCD group in anterior (p = 0.021), right molar (p < 0.000), and left premolar (p < 0.000) regions in long-term. There is no statistically significant difference between the CCD and ISO groups in right premolar (p = 0.200) and left premolar (p = 0.134) regions in long term. Both edentulous groups showed significantly lower mean MCW (p < 0.000), PMI (p < 0.000), AI (p < 0.000), GI (p < 0.012), and AEI (p < 0.002) than the without tooth loss group. There is no statistically significant difference between the CCD and ISO groups in terms of changes in the mean MCW, PMI, AI, GI, and AEI measurement in short and long term (p > 0.000). In the short and long term, edentulism reduced alveolar crest height, MCW, and AEI in individuals, but had no effect on PMI, AI, or GI. The use of prosthesis did not prevent the decrease of alveolar crest height, MCW, or AEI (CCP or ISO). In the short and long term, however, ISO created less ABL in the mandibular anterior and molar regions than CCD. ABL cannot be halted in edentulous people, but by using ISO instead of CCD for rehabilitation, resorption can be reduced.