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BMC Oral Health Jun 2024The aim of the study was to investigate the changes occurring in the mandibular condyle by using mentoplate together with rapid maxillary expansion (MP-RME) treatment in...
BACKGROUND
The aim of the study was to investigate the changes occurring in the mandibular condyle by using mentoplate together with rapid maxillary expansion (MP-RME) treatment in the correction of skeletal class III relationship, using fractal analysis (FA).
METHODS
The sample consisted of 30 individuals (8-11 years) diagnosed with skeletal Class III malocclusion who underwent MP-RME treatment. Archival records provided cone-beam computed tomography (CBCT) images taken at two intervals: before MP-RME treatment (T0) and after treatment (T1). The CBCT images were obtained using standardized settings to ensure consistency in image quality and resolution. The trabecular structures in the bilateral condyles at both T0 and T1 were analyzed using FA. The FA was performed on these condylar images using the Image J software. The region of interest (ROI) was carefully selected in the condyle to avoid overlapping with cortical bone, and the box-counting method was employed to calculate the fractal dimension (FD). Statistical analysis was conducted to compare the FD values between T0 and T1 and to evaluate gender differences. The statistical significance was determined using paired t-tests for intra-group comparisons and independent t-tests for inter-group comparisons, with a significance level set at p < 0.05.
RESULTS
The analysis revealed no statistically significant differences in the trabecular structures of the condyles between T0 and T1 (p > 0.05). However, a significant gender difference was observed in FA values, with males exhibiting higher FA values in the left condyle compared to females at both T0 and T1 (p < 0.05). Specifically, the FA values in the left condyle increased from a mean of 1.09 ± 0.09 at T0 to 1.13 ± 0.08 at T1 in males, whereas in females, the FA values remained relatively stable with a mean of 1 ± 0.09 at T0 and 1.03 ± 0.11 at T1.
CONCLUSION
The findings indicate that MP-RME therapy does not induce significant alterations in the trabecular structure of the mandibular condyle. These results suggest the treatment's safety concerning the structural integrity of the condyle, although the observed gender differences in FA values warrant further investigation.
Topics: Humans; Mandibular Condyle; Malocclusion, Angle Class III; Female; Male; Cone-Beam Computed Tomography; Child; Palatal Expansion Technique; Fractals
PubMed: 38915000
DOI: 10.1186/s12903-024-04506-0 -
Scientific Reports Nov 2023This study aimed to examine the difference between the fractal dimension (FD) values of the mandibular trabecular bone and the panoramic mandibular index (PMI),...
This study aimed to examine the difference between the fractal dimension (FD) values of the mandibular trabecular bone and the panoramic mandibular index (PMI), mandibular cortical index (MCI) and mandibular cortical thickness (MCW) of patients with ankylosing spondylitis (AS) and healthy control group. A total of 184 individuals (92 cases, 92 controls), were examined in our study. PMI, MCI, and MCW values were calculated on panoramic images of all individuals. For FD values, the region of interest (ROI) was selected with the size of 100 × 100 pixels from the right-left gonial and interdental regions and 50 × 50 pixels from the condylar region. Degenerative changes in the temporomandibular joint (TMJ) region were recorded. PMI, MCI, and MCW values showed statistically significant differences between the groups (p = 0.000, p < 0.001). The radiological signs of mandibular cortical resorption were more severe in the case group than in the control group. PMI and MCW values were found to be lower in the case group than in the control group. It was determined that the number of C3 and C2 values, among the MCI values, was higher in the case group. Only the FD values of the ROI selected from the condyle region were found to be statistically significant and were lower in the case group (p = 0.026, p < 0.05). Degenerative changes in the TMJ region were significantly more frequent in the case groups (p = 0.000, p < 0.001). The fact that the mandibular cortex shows more resorptive features in individuals with AS may require further evaluation in terms of osteoporosis. Because of the low FD values of the condylar regions of these patients and the more frequent degenerative changes, the TMJ region should be followed carefully. Detailed examination of the mandibular cortex and condylar region is beneficial in patients with AS for screening and following osteoporotic changes in these individuals, which is essential for the patient's life quality.
Topics: Humans; Cancellous Bone; Spondylitis, Ankylosing; Bone Density; Radiography, Panoramic; Mandible; Fractals
PubMed: 37957329
DOI: 10.1038/s41598-023-47233-2 -
Journal of Biomechanics Oct 2023Total temporomandibular joint (TMJ) replacement surgery aims to improve mandibular function, reduce pain and enhance quality of life in patients suffering from end-stage...
Total temporomandibular joint (TMJ) replacement surgery aims to improve mandibular function, reduce pain and enhance quality of life in patients suffering from end-stage TMJ disorders. Traditional post-operative jaw evaluation is carried out using measurement of maximum interincisal opening distance; however, this can correlate poorly to joint function. The present study aimed to evaluate three-dimensional (3D) jaw motion during border movements and chewing in unilateral total TMJ replacement patients and healthy controls. Motion analysis experiments were performed on six unilateral total TMJ replacement patients and ten age-matched healthy controls. Subject-specific motion tracking plates worn by each participant were registered to CT scans of each participant's skull and mandible to enable anatomical mandibular kinematics measurement using an optoelectronic system. Participants performed 15 repetitions of maximal opening, protrusion, lateral excursions, and chewing cycles. Total TMJ replacement patients had significantly smaller incisal displacements at maximum mouth opening relative to the controls (median difference: 7.1 mm, p = 0.002) and decreased anterior translation of the prosthetic condyle (median difference: 10.5 mm, p = 0.002). When TMJ replacement subjects chewed using their contralateral molars, there was a significant increase in inferior condylar translation of the non-working condyle (median difference: 9.7 mm, p = 0.016). This study found that unilateral total TMJ replacement surgery was associated with mouth opening capacity within the range of healthy individuals, but reduced anterior movement of the prosthetic condyle and restricted protrusion and lateral excursions. The results provide future direction for prosthetic TMJ design to enhance postsurgical implant functionality and improve long-term clinical outcomes for prosthesis recipients.
Topics: Humans; Biomechanical Phenomena; Quality of Life; Temporomandibular Joint; Joint Prosthesis; Mandible; Range of Motion, Articular; Mandibular Condyle
PubMed: 37660523
DOI: 10.1016/j.jbiomech.2023.111741 -
Journal of Dental Research Jan 2024The mandibular condylar cartilage (MCC) is an essential component of the temporomandibular joint, which orchestrates the vertical growth of the mandibular ramus through...
The mandibular condylar cartilage (MCC) is an essential component of the temporomandibular joint, which orchestrates the vertical growth of the mandibular ramus through endochondral ossification with distinctive modes of cell differentiation. Parathyroid hormone-related protein (PTHrP) is a master regulator of chondrogenesis; in the long bone epiphyseal growth plate, PTHrP expressed by resting zone chondrocytes promotes chondrocyte proliferation in the adjacent layer. However, how PTHrP regulates chondrogenesis in the MCC remains largely unclear. In this study, we used a knock-in reporter strain to map the localization of PTHrP cells in the MCC and define the function of PTHrP in the growing mandibular condyle. In the postnatal MCC of mice, PTHrP-mCherry was specifically expressed by cells in the superficial layer immediately adjacent to RUNX2-expressing cells in the polymorphic layer. PTHrP ligands diffused across the polymorphic and chondrocyte layers where its cognate receptor PTH1R was abundantly expressed. We further analyzed the mandibular condyle of mice lacking functional PTHrP protein (PTHrP-KO). At embryonic day (E) 18.5, the condylar process and MCC were significantly truncated in the PTHrP-KO mandible, which was associated with a significant reduction in cell proliferation across the polymorphic layer and a loss of SOX9 cells in the chondrocyte layers. The PTHrP-KO MCC showed a transient increase in the number of Col10a1 hypertrophic chondrocytes at E15.5, followed by a significant loss of these cells at E18.5, indicating that superficial layer-derived PTHrP prevents premature chondrocyte exhaustion in the MCC. The expression of , but not , was significantly reduced in the polymorphic layer of the PTHrP-KO MCC. Therefore, PTHrP released from cells in the superficial layer directly acts on cells in the polymorphic layer to promote proliferation of chondrocyte precursor cells and prevent their premature differentiation by maintaining expression, revealing a unique PTHrP gradient-directed mechanism that regulates MCC chondrogenesis.
Topics: Animals; Mice; Cartilage; Cell Differentiation; Chondrocytes; Chondrogenesis; Core Binding Factor Alpha 1 Subunit; Mandibular Condyle; Parathyroid Hormone-Related Protein
PubMed: 38058151
DOI: 10.1177/00220345231208175 -
Medicine Feb 2024To evaluate the feasibility of temporomandibular disorder (TMD) diagnosis with panoramic radiography, and provide standardized data for artificial intelligence-assisted...
To evaluate the feasibility of temporomandibular disorder (TMD) diagnosis with panoramic radiography, and provide standardized data for artificial intelligence-assisted diagnosis by measuring the differences in the condylar and mandibular ramus heights. A total of 500 panoramic radiographs (219 male and 281 female participants) of healthy individuals were examined. The panoramic machine compatible measurement software, SCANORA 5.2.6, was used to measure the bilateral condylar height and mandibular ramus height, and SPSS 27.0 was used to calculate the left- and right-side differences in condylar height and mandibular ramus height of healthy individuals. Magnetic resonance images of the temporomandibular joint region obtained from 46 outpatients in the Stomatology Department were selected along with their corresponding panoramic radiographs. The left- and right-sided differences were measured and compared with the magnetic resonance imaging results. The measurement data are expressed as mean ± standard deviation (mm). t Tests were used to analyze data from healthy male and healthy female groups. The findings revealed that while there was no significant difference (P > .05) in the height of the condyle between men and women, there was a significant difference (P < .05) in the height of the mandibular ramus. In healthy population, the difference in height between the left and right condyle was 1.09 ± 0.99 mm. The difference in height of mandibular ramus in men was 1.26 ± 0.85 mm and that in women was 1.19 ± 0.87 mm. For the diagnosis of TMD, the sensitivity of panoramic radiographs was 94.74% (36/38), specificity was 75.00% (6/8), and diagnostic accuracy was 91.30% (42/46). The height of the right and left lateral condyles was not identical in healthy individuals, resulting in a discernible height discrepancy. In addition, the height of the mandibular ramus varied. By considering the left-right lateral height differences identified in this study along with clinical examination, it is possible to employ this metric as a preliminary screening tool for patients with TMD. Further, the use of panoramic radiographs for initial TMD screening is both viable and significant.
Topics: Humans; Male; Female; Mandibular Condyle; Radiography, Panoramic; Artificial Intelligence; Temporomandibular Joint; Temporomandibular Joint Disorders
PubMed: 38306563
DOI: 10.1097/MD.0000000000036469 -
Journal of Clinical Medicine Jul 2023The treatment of dentofacial deformities generally includes orthognathic surgery in which mandibular condyle changes following surgery are a common cause of relapse....
The treatment of dentofacial deformities generally includes orthognathic surgery in which mandibular condyle changes following surgery are a common cause of relapse. This study investigated the changes in the mandibular condyle and related muscles to identify the factors that affected the changes in the mandibular condyle after orthognathic surgery in skeletal class II patients. This research studied 60 joints in 30 patients with skeletal class II dentofacial deformities who received surgical orthodontic treatment, including bilateral sagittal split ramus osteotomy, and underwent computed tomography before and after orthodontic treatment. The mandibular condyle, masseter, and medial pterygoid muscles were reconstructed and measured in 3D. Condylar positional and morphology changes, masseter and medial pterygoid muscle volume, temporomandibular joint (TMJ) pain, and distal segment movement were analyzed. The study observed that both the masseter and medial pterygoid muscle volumes decreased with statistical significance. The changes in the horizontal direction were positively correlated with the amount of movement. The findings indicated that mandibular condyle changes were significantly affected by the movement of the distal segment, the medial pterygoid muscle volume, and the direction of the distal segment, which influenced the treatment's long-term stability after orthognathic surgery.
PubMed: 37510990
DOI: 10.3390/jcm12144875 -
BMC Oral Health Feb 2024Sedentary behavior (SB) may contribute to obesity and lower extremity fluid retention, which may favor the development of obstructive sleep apnea (OSA). However, linking...
BACKGROUND
Sedentary behavior (SB) may contribute to obesity and lower extremity fluid retention, which may favor the development of obstructive sleep apnea (OSA). However, linking sedentary behavior to OSA is unclear. The purpose of this study was to determine if there is an association between SB and OSA.
METHODS
Three typical questions in the NHANES questionnaire(①The frequency of feeling excessively sleepy per month. ②The frequency of gasping, snorting or stopping breathing per week. ③The frequency of snoring per week.) have been used for the assessment of OSA. A physical activity questionnaire(On a typical day, the amount of time you spend sitting or reclining.) was used to assess SB. This secondary analysis included National Health and Nutrition Examination Survey (NHANES) participants (unweighted = 20,115). Weighted sample and multiple logistic regression complex sample analysis techniques were used in this study.
RESULTS
After adjustment for confounders, participants with SB(> 8 h/d) had a higher risk of OSA compared to SB(< 4 h/d). Stratified analysis by gender showed that there was no significant association of SB and OSA in men. However, in women, with SB(< 4 h/d) as the reference, participants with(≥ 4 h/d) had an increased risk of OSA. By age-stratified analysis, the association of SB with OSA was stronger among older participants.
CONCLUSION
Analysis in this study showed a positive association between SB and OSA, more pronounced in women and participants older than 60 years old.
Topics: Male; Humans; Female; Middle Aged; Nutrition Surveys; Cross-Sectional Studies; Sedentary Behavior; Sleep Apnea, Obstructive; Surveys and Questionnaires
PubMed: 38347492
DOI: 10.1186/s12903-024-03960-0 -
The Saudi Dental Journal Sep 2023An anterior bite plane (ABP) is an orthodontic appliance that prevents posterior teeth from making contact. This appliance's functional concept is to reduce muscle...
OBJECTIVES
An anterior bite plane (ABP) is an orthodontic appliance that prevents posterior teeth from making contact. This appliance's functional concept is to reduce muscle activity, overcome deep overbite, and temporomandibular joint (TMJ) disorders (TMD). However, ABP treatment for malocclusion frequently results in unfavorable reversible and irreversible long-term effects. This problem presents difficulties for dentists in developing an appropriate treatment modification plan in order to achieve the best results. As a result, the goal of this study is to observe the effects of different ABP types on the TMJ and mandible.
MATERIALS AND METHODS
Thirty-six three-month-old male Wistar strain rats were divided into three groups: control, upper flat, and upper-lower inclined ABP. The overbite and body weight were measured. TMJ was examined histologically using hematoxylin and eosin (HE). To observe the entire mandibular bone in response to ABP, mandibular planes and angulations were measured.
RESULTS
After 7 days, the upper-lower inclined ABP group has significantly lower body weight than the control group. On days 7 and 14, overbite was significantly reduced in both the upper flat and upper-lower inclined ABP groups. The superficial layer of the condyle was depleted in both ABP groups, according to HE analysis. Mandibular angle analysis revealed that the upper-lower inclined ABP group had a greater incisal and ramus angle. Furthermore, lower incisor (Li)-condyle (Co) mandibular points increased significantly more in the upper-lower inclined ABP group than in the control group.
CONCLUSION
According to this study, various forms of ABP may have an impact on the TMJ and mandibular morphology, specifically on the length, angulation, and superficial surface of the condyle.
PubMed: 37823082
DOI: 10.1016/j.sdentj.2023.06.002 -
Cureus May 2024The human mandible plays a significant role in personal identification due to its unique morphological characteristics. The coronoid process, condyle, and sigmoid notch...
Distinctive Anatomical Patterns of the Mandibular Coronoid Process, Condyle, and Sigmoid Notch: Cone Beam Computed Tomography (CBCT) Imaging for Advanced Personal Identification.
INTRODUCTION
The human mandible plays a significant role in personal identification due to its unique morphological characteristics. The coronoid process, condyle, and sigmoid notch exhibit variations that can be utilized for forensic and anthropological purposes. This study aims to analyze the morphological diversities of these mandibular features in our ethnic group using cone beam computed tomography (CBCT) imaging.
MATERIALS AND METHODS
A retrospective analysis was conducted using 100 CBCT images obtained from the archives of the Department of Oral Medicine and Radiology. The images were captured using Carestream 9600 machines (Carestream Dental LLC, Atlanta, GA) with standard exposure parameters. Curved slicing screenshots were utilized for tracing the morphological variations of the coronoid process, condyle, and sigmoid notch.
RESULTS
Out of 100 CBCT images analyzed (corresponding to 200 sides), the shape-wise distribution of the coronoid process revealed that a triangular shape was most commonly observed in 59% (118) of cases. The condyle exhibited a predominantly round shape in 38.7% (77) of cases based on shape parameter-wise distribution. Similarly, the sigmoid notch displayed a round shape in 40.5% (81) of cases based on shape-wise distribution.
CONCLUSION
Personal identification using radiographs has gained significance in the current scenario due to its feasibility. Cone beam computed tomography imaging has become a reliable and accurate method for revealing hidden details in forensic odontology, especially when antemortem records are available. This research sheds light on the morphological variations of the mandibular coronoid process, condyle, and sigmoid notch within our ethnic cohort, enhancing personal identification practices. Further research encompassing larger sample sizes and diverse populations would enhance the applicability of these findings in forensic and anthropological contexts.
PubMed: 38910783
DOI: 10.7759/cureus.60978