Difference In Condylar Position Research Articles

A comparative study of condyle position in temporomandibular disorder patients with chewing side preference using cone-beam computed tomography.

Chewing side preference (CSP) could cause structural and morphological changes of temporomandibular joint (TMJ) and has been suggested as one aetiology of temporomandibular disorders (TMDs), but the condylar position in TMD patients with CSP is unknown. To compare the condylar position in the TMD patients with and without CSP. Ninety TMD patients with unilateral symptom (69 with CSP and 21 without CSP) and 20 asymptomatic participants received cone-beam computed tomography. The condylar position was determined based on the measurements of sagittal joint spaces. Intergroup and intra-group comparisons of the condylar position were performed. The condyles in asymptomatic participants located nearly randomly in anterior, centric and posterior positions. Patients without CSP had significantly more posterior condyles than asymptomatic participants (57.1% vs 30.0%, p<0.05). In patients with CSP, 50.7% of the condyles on the preferred chewing side and 42.0% on the unpreferred side located posteriorly, reaching no significant level compared with the asymptomatic participants and patients without CSP (p>0.05). The symptomatic joints and asymptomatic joints in patients with CSP and without CSP showed no significant differences in condylar position. While patients without CSP had significantly more posterior condyles in symptomatic joints than asymptomatic participants (p<0.05), patients with CSP showed a trend towards more posterior condyles in symptomatic joints compared with the asymptomatic participants (53.6% vs 30.0%, p=0.054). Condylar position is not a strong indicator to differentiate CSP-related TMDs from non-CSP-related TMDs. Posterior condyle could not be viewed as one indicator of TMD.

Evaluation of the dimensions, morphology, and position of the mandibular condyles in individuals with neurofibromatosis 1: a case-control study.

The aim of this study was to evaluate the mandibular condyles of neurofibromatosis 1 (NF1) individuals without facial plexiform neurofibroma using cone beam computed tomography images. Eighty cone beam computed tomography scans (160 mandibular condyles) were analyzed: 40 from NF1 individuals (study group) and 40 from individuals without NF1 (control group). The anteroposterior and mediolateral dimensions, height, and volume of the mandibular condyles were measured. The mandibular condyles were classified according to their morphology: healthy (absence of morphological changes), with flattening (loss of rounded contour of at least one of the surfaces), with erosion (loss of continuity of the cortical bone), with osteophyte (exophytic formation of the condyle surface), and with sclerosis (any increase in the cortical thickness in the load-bearing areas). Furthermore, the position of the mandibular condyles in relation to the joint fossa in an anteroposterior view was classified as anterior, concentric, or posterior. The study group had a higher anteroposterior dimension of the mandibular condyles compared with the control group (p < 0.05). There were no differences in condylar morphology and position between both groups (p > 0.05). The morphological alterations were not associated with sex or age in any group evaluated (p > 0.05). For both groups, the concentric position was the most common. For the study group, there was a significant difference in the condylar position between the sides (p < 0.05). NF1 individuals without facial plexiform neurofibroma present a high prevalence of condyles with a large anteroposterior dimension and asymmetric position in the joint fossa. However, no morphological and volumetric changes were observed in the mandibular condyles of them. The knowledge of the TMJ alterations in individuals with NF1 is important to establish an evaluation protocol, which would allow early intervention if indicated.

Evaluation of Condylar Positional, Structural, and Volumetric Status in Class III Orthognathic Surgery Patients.

Background and objectives: The need to evaluate the condylar remodeling after orthognathic surgery, using three-dimensional (3D) images and volume rendering techniques in skeletal Class III patients has been emphasized. The study examined condylar positional, structural, and volumetric changes after bimaxillary or single-jaw maxillary orthognathic surgeries in skeletal Class III patients using the cone-beam computed tomography. Materials and Methods: Presurgical, postsurgical, and one-year post-surgical full field of view (FOV) cone-beam computed tomography (CBCT) images of 44 patients with skeletal Class III deformities were obtained. Group 1 underwent a bimaxillary surgery (28 patients: 24 females and 4 males), with mean age at the time of surgery being 23.8 ± 6.0 years, and Group 2 underwent maxillary single-jaw surgery (16 patients: 8 females and 8 males), with mean age at the time of surgery being 23.7 ± 5.1 years. After the orthognathic surgery, the CBCT images of 88 condyles were evaluated to assess their displacement and radiological signs of bone degeneration. Three-dimensional (3D) condylar models were constructed and superimposed pre- and postoperatively to compare changes in condylar volume. Results: Condylar position was found to be immediately altered after surgery in the maxillary single-jaw surgery group, but at the one-year follow-up, the condyles returned to their pre-surgical position. There was no significant difference in condylar position when comparing between pre-surgery and one-year follow-up in any of the study groups. Condylar rotations in the axial and coronal planes were significant in the bimaxillary surgery group. No radiological signs of condylar bone degeneration were detected one year after the surgery. Changes in condylar volume after surgery were found to be insignificant in both study groups. Conclusions: At one year after orthognathic surgery, there were no significant changes in positional, structural, or volumetric statuses of condyles.

3D CBCT Evaluation of Condyle Position in Skeletal Class I &amp; Class III Growing Subjects

Introduction: Evaluation of temporo-mandibular joint (TMJ) anatomy and function is an essential part of orthodontic diagnosis and treatment planning. It has been hypothesized that dental and skeletal malocclusions alter the functional loading of TMJ which can affect joint morphology.Objective: Three dimensional (3D) evaluation of condylar position using CBCT in skeletal Class I and Class III growing subjects.Materials &amp; Method: CBCT images of ten growing skeletal Class I &amp; ten Class III patients in the age range of 7-14 years were analyzed. 3D condylar position were evaluated representing antero-posterior, vertical, laterolateral position of condyle, axial condylar angle and coronal condylar angles which were measured in axial, coronal and sagittal sections using Dolphin Imaging software. Antero-posterior and vertical difference of right and left condyle were measured in axial and coronal sections respectively.Result: Paired t-Test revealed no significant difference between right and left sides of condyle in skeletal Class I as well as Class III subjects. Independent t-test and Mann-Whitney U test showed no significant difference between position of condyle in ClassI and Class III subjects.Conclusion: 3D CBCT analysis shows no significant difference in condylar position of skeletal Class I and Class III subjects.

Evaluating condylar position in different skeletal malocclusion patterns: A cephalometric study

ContextThe cranial base and variations in its morphology affect the anterior-posterior positioning of jaws causing changes in the glenoid fossa and condylar position.AimsTo evaluate the condylar position in patients with different skeletal sagittal malocclusion patterns.Materials and MethodsPretreatment lateral cephalometric radiographs of 112 subjects (both males and females) were categorized into three classes (Class I, Class II, Class III) based on their ANB angulation and studied for N-S-Ar (saddle angle), S-Ar-Go (articular angle), S-Ar (posterior cranial base length).Statistical AnalysisShapiro-Wilk test was done to check for normality of the distribution of values. Groups were evaluated using parametric tests (one-way ANOVA). Significance for all tests was predetermined asP&lt; 0.05.ResultsN-S-Ar and S-Ar-Go and also S-Ar did not vary significantly in all the three classes. N-S-Ar and S-Ar-Go angles have shown a significant negative correlation in all the three classes.ConclusionsThere is no significant difference in condylar position in different skeletal malocclusion patterns. N-S-Ar and S-Ar-Go angles show a negative correlation in any skeletal malocclusion pattern.

Association between mandibular condylar position and clinical dysfunction index

ObjectivesCondylar position in the glenoid fossa has been associated with temporomandibular disorders. The purpose of the present study was to investigate the correlation between clinical dysfunction index (Di) and mandibular condylar position in patients with temporomandibular joint dysfunction (TMD) using cone beam computed tomography (CBCT). MethodsIn this cross-sectional study, participants were recruited from the Department of Maxillofacial Radiology at Shiraz Dental University in Iran. The condylar position was assessed on the CBCT images of 120 temporomandibular joints in 60 patients with TMD. Patients were divided into 3 groups based on Helkimo's clinical Di. The chi-square test was used to correlate degree of the Helkimo's Di with the mandibular condylar position. The p value was set at 0.05. ResultsA total of 60 patients (42 women and 18 men; mean age, 33.4 years) participated in this study. Significant differences in condylar position were found among the 3 groups (Di I, II, and III) (p < 0.05). Patients with mild to moderate TMD were found to have anteriorly and concentric seated condyles. Posteriorly seated condyles were found in patients with severe TMD. ConclusionCondylar position is associated with different severity of TMD.

Cone-Beam Computed Tomographic Assessment of Mandibular Condylar Position in Patients with Temporomandibular Joint Dysfunction and in Healthy Subjects.

Statement of the Problem. The clinical significance of condyle-fossa relationships in the temporomandibular joint is a matter of controversy. Different studies have evaluated whether the position of the condyle is a predictor of the presence of temporomandibular disorder. Purpose. The purpose of the present study was to investigate the condylar position according to gender in patients with temporomandibular disorder (TMD) and healthy controls using cone-beam computed tomography. Materials and Methods. CBCT of sixty temporomandibular joints in thirty patients with TMD and sixty joints of thirty subjects without TMJ disorder was evaluated in this study. The condylar position was assessed on the CBCT images. The data were analyzed using Pearson chi-square test. Results. No statistically significant differences were found regarding the condylar position between symptomatic and asymptomatic groups. Posterior condylar position was more frequently observed in women and anterior condylar position was more prevalent in men in the symptomatic group. However, no significant differences in condylar position were found in asymptomatic subjects according to gender. Conclusion. This study showed no apparent association between condylar positioning and clinical findings in TMD patients.

Correlation between centric relation–maximum intercuspation discrepancy and temporomandibular joint dysfunction

Objective. To investigate the relationship between centric relation–maximum intercuspation (CR-MI) discrepancy and temporomandibular joint dysfunction (TMD) in pre-treated orthodontic patients. Material and methods. The study involved an experimental group of 107 pre-treated orthodontic patients with signs and symptoms of TMD aged 18–32 years, and a control group of 70 students with no signs and symptoms of TMD aged 20–30 years. The psychological condition of subjects was evaluated using two standard questionnaires, and a clinical examination performed to assess masticatory musculature and temporomandibular joint (TMJ) function, and to establish the presence or absence of TMD. Helkimo indices, the anamnestic dysfunction index (Ai) and the clinical dysfunction index (Di), were determined. Dental casts were mounted on a semi-adjustable articulator in CR using a CR bite record taken by bilateral manipulation and verified by load testing and face bow records. Differences in condylar position between CR and MI in the three planes of space were determined using the condyle position indicator. Results. A positive CR-MI discrepancy, defined as a discrepancy exceeding 1 mm in the vertical or horizontal planes or 0.5 mm in the transverse plane, was found in 72.9% of the experimental and 11.4% of the control group. Comparison of the groups showed a significant difference (χ2 = 22.67, P < 0.001). CR-MI discrepancy was significantly correlated with Di and Ai in all subjects (P < 0.01). Conclusions. There was CR-MI discrepancy in most of the pre-treated patients with signs and symptoms of TMD. This discrepancy may be a contributory factor to the development of TMD in these patients.

Three-dimensional analysis of models articulated in the seated condylar position from a deprogrammed asymptomatic population: A prospective study. Part 1

The seated condylar position (SCP), also known as centric relation (CR), is considered the most reliable and reproducible reference point for accurately recording the relationship of the mandible to the maxilla. Therefore, a determination of the SCP/CR is a prerequisite for the analyses of the dental interarch, condylar position, and skeletal relationships. The purpose of this prospective study was to statistically evaluate the 3-dimensional nature of dental interarch displacement and condylar displacement between the SCP/CR and maximum intercuspation or centric occlusion (MIC/CO). The records of 596 consecutive asymptomatic patients having routine orthodontic treatment in a private practice were used. The initial premature occlusal contact and 3-dimensional dental interarch displacement were measured by the analysis of models, mounted on an articulator (Panadent, Grand Terrrace, Calif) in the SCP/CR, by using the modified (nonmanipulated) 2-piece wax SCP/CR recording method with deprogramming. Three-dimensional condylar displacement was measured by analysis of the graphic registrations, produced by condylar position instrumentation, and evaluated for frequency, direction, and magnitude of displacement. The dental interarch discrepancy in the SCP/CR was significantly different from that observed in MIC/CO, with posterior premature contacts (94.0%), increased overjet, decreased overbite, midline differences, and Angle classification changes. A difference in condylar position between the SCP/CR and MIC/CO in at least 1 plane was detected for every asymptomatic patient and every condyle. The most prevalent types of directional change in condylar position were inferior (down) (97.0%) and distal (posterior) (66.7%) when the teeth were brought into MIC/CO. The mean difference in condylar position between the SCP/CR and MIC/CO was .86 mm in the horizontal plane, 1.80 mm in the vertical plane, and .26 mm in the transverse plane. No correlation was found between a patient's age or sex and the magnitude of condylar displacement. There is a significant difference in the occlusion when it is dictated by the teeth and when it is dictated by the condyles. This difference is quantifiable at both the occlusal and condylar levels.

Is condylar position a predictor for functional signs of TMJ hypermobility?

Temporomandibular joint (TMJ) hypermobility is noted only when it interferes with smooth mandibular movements. These interferences (viz. clicking sounds and jerky mandibular movements) result from condylar dislocation in front of the eminence at wide mouth opening, or alternatively in front of the articular disc (posterior disc displacement). The aim of this study was to test the hypothesis that condyles of hypermobile persons are positioned more anterosuperiorly to the crest of the eminence during maximum mouth opening than those of persons without TMJ hypermobility. Possible posterior disc displacement was also evaluated. Nine persons with symptomatic hypermobility and nine control persons free of internal derangements were included, their diagnoses being based upon opto-electronic movement recordings. Condylar positions during maximum mouth opening were analysed on magnetic resonance images with two slightly different methods, showing the degree to which the condyles are displaced around the eminence. No posterior disc displacements were found in any of the magnetic resonance images. After excluding an outlier and using both measurement methods, a small difference in condylar position was found between the two groups of subjects. The condyles of all hypermobile persons travelled beyond the eminence; however, so were the condyles of nearly half of the non-hypermobiles. The large overlap between both groups suggests that condylar position alone is not a good predictor for symptomatic TMJ hypermobility. It is probably the combination of condylar location in front of the eminence with a particular line of action of the masticatory muscles, which gives rise to functional signs of hypermobility.

A study of the relationship between the position of the condylar head and displacement of the temporomandibular joint disk.

To examine the possible relationship between condylar position and disk displacement in the TMJ. Forty-eight joints with no disk displacement (NDD), 84 joints with a reducible displaced disk (RDD) and 99 joints with a permanently displaced disk (PDD) were selected. The positions of the condyle and TMJ disk were calculated from lateral MR images. There were significant differences in condylar position between the joints with NDD and RDD, while there was no difference between those with NDD and PDD (Kruskal-Wallis and post-hoc test, P<0.05). There was also a significant correlation between the position of the condylar and the displaced disk (Spearman's rank correlation, P<0.05). The condyle was located more anteriorly with advancing disk displacement. We suggest that if the disk displacement is slight, the condyle is displaced posteriorly: as the disk displacement becomes more severe (i.e. more anteriorly displaced), the condyle returns to the concentric position.

Tomographic assessment of temporomandibular joints in patients with malocclusion.

There is a paucity of information on the morphological assessment of the temporomandibular joint in relation to varying skeletal and dental relationships. The purpose of this study was to evaluate the morphologic relationship of the condyle and fossa in patients with different malocclusions and skeletal relationships. Pretreatment records of 232 orthodontic patients, 95 males and 137 females, of Caucasian descent and ranging in age from 9 years 4 months to 42 years 6 months, were examined. Records included dental casts, lateral cephalometric radiographs, hand-wrist radiographs, and corrected tomograms of right and left TM joints. Nonconcentricity and mild asymmetry of the condyle-fossa relationship were commonly observed. The left condyle was found to be more anteriorly positioned than the right, with the mean percentage of joint space being 6.93% on the left side and -1.24% on the right. Skeletal and dental Class III patients demonstrated significantly more anteriorly positioned condyles (P < 0.05). There were no significant differences in condylar position between Class I and Class II groups based on ANB or Angle's classification. Further, no significant difference in condylar position was observed between groups based on overbite or crossbite.

Comparative studies on check-bite and central-bearing-point method for the remounting of complete dentures

Thirty-six complete dentures were remounted both with check-bite as well as central-bearing-point (CBP) registration. The mandibular or denture position was registered in the condylar area three times with each method. Two independent operators carried out the registrations. One half of patients had their occlusion equilibrated according to the check-bite registration, the other half in the central-bearing-point position. After individual determination of the hinge axis the upper dentures were mounted by a face-bow transfer into a Dentatus articulator. A total of six registrations was performed and repeatedly compared in the condylar area in three dimensions using a computer supported measuring device. The reproducibility of the check-bite registration was 0.37 +/- 0.33 mm, with a maximum of 1.77 mm. For the central-bearing-point method this was 0.29 +/- 0.26 mm with a maximum of 1.56 mm. The mean difference in condylar position between both methods was 0.66 +/- 0.55 mm with a maximum of 4.02 mm. A third independent operator re-examined 30 of the patients 2-3 weeks after the remounting and evaluated the adaptation to the new dentures. Those patients whose dentures were equilibrated with the central-bearing-point method tended to cope better with their dentures and suffered on average from fewer pressure spots.

Perceptibility of Condylar Displacement through Transcranial Radiographs and Split-Cast Technique on Dry Skull

The authors compared the limit of perceptibility of transcranial radiographs and of the split-cast technique in detecting differences in condylar position. The study was carried out on two dried human skulls. The results indicated the split-cast method was superior to the radiographic method as it allowed differences in condylar position of 0.2 mm, both in sagittal and frontal plane, to be detected. The limit of perceptibility of transcranial radiographs for position differences in the sagittal plane was 0.6 mm for naked-eye examination and 0.2 mm when using the subtraction method. Differences in condylar position even as large as 0.6 mm in the frontal plane could not clearly be seen by naked-eye examination, and with the subtraction technique only if they were of at least 0.4 mm.

Condylar position and extraction treatment

By means of corrected tomography, the positions of the condyles in patients who had undergone four-premolar extraction treatment (20 edgewise and 7 Begg) were compared with the condylar positions of patients who had not yet received orthodontic treatment. No significant between-group differences in condylar position were noted. In addition, the relationship between bite depth and condylar position was examined and no significant correlation was found. Thus, as performed in this study, condylar position was unrelated to extraction treatment and to bite depth.

Comparison of the multiphasic dysfunction profile with lateral transcranial radiographs

Lateral transcranial radiographs of 926 patients were analyzed for condylar position, TMJ space, and obvious condylar morphologic changes. Differences in condylar position and joint space variations were noted between men and women. An increase in nonconcentric condylar position, joint space variations, and condylar morphologic changes were found with advancing age. There was a significant correlation of condylar position, joint space variations, and condylar morphology with mandibular dysfunction profile scores. Mandibular dysfunction is manifested by a wide range of signs and symptoms, none of which is always present with the disorder. Although TRs are limited in their total diagnostic value, their use in discerning major TMJ changes serves as an important adjunct in the examination and diagnosis of mandibular dysfunction.

A radiographic analysis of small changes in condylar position.

The investigation was designed to test the precision of the subtraction technique as a means of detecting small differences in condylar position following one-handed push-back and bimanual manipulation of the mandible to Centric Relation. The material included seven healthy adults free from signs and symptoms involving the temporomandibular joints and masticatory muscles. An analysis error of approximately 10% of the inter-individual variation was found regarding registrations of both horizontal and vertical differences between the two condylar positions. Corresponding figures of 18% and 12% were found in relation to the intra-individual variation between sides. The influence of left/right condylar differences was sufficient to motivate bilateral radiographic registration, however, index play could be disregarded. A bilateral model for continued registration is presented offering an improvement on the reported precision of a number of indirect recording techniques. Increasing the number of patients is shown to be the most suitable way of achieving further improvement in the model.