Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study analyzed the occlusions of 489 children at the onset of the mixed dentition period (mean age 5.1 years, range 4.0-7.8 years). These children participate in an ongoing clinical trial that is investigating the effects of orthodontic intervention in the early mixed dentition. The aim was to report the occlusal findings at the baseline. The frequencies of mesial step, flush terminal plane, and distal step were 19.1%, 47.8%, and 33.1%, respectively. The canine relationship was Class I in 46.1%, Class II in 52.4%, and Class III in 1.5% of the sides examined. An asymmetrical canine relationship was found in 30.1% of the children, significantly more often on the right side than on the left (P <.001). Overjet ranged from -2 to +10 mm with a mean of 2.9 mm. Overbite ranged from -5 to +8 mm with a mean of 2.8 mm. Excessive (> or =4 mm) overjet was found in 26.7% and overbite in 33.8% of the children; in 15.5% of the children, both variables were 4 mm or more. Anterior crowding was detected in the maxillary arch in 11.6% and in the mandibular arch in 38.9% of the children. Girls showed mandibular crowding more often than boys (P <.01). A posterior crossbite was found in 7.5% of the children, unilaterally in 6.4% and bilaterally in 1.1%. Scissors-bite was detected in 1.1% and an anterior crossbite in 2.2% of the children. The mean maximal opening was 40.3 mm. Joint sounds were registered in 5.2% of the children. The prevalence of malocclusion was between 67.7% and 92.7%, depending on the values of unacceptable parameters used for each occlusal characteristic.
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PMID:Occurrence of malocclusion and need of orthodontic treatment in early mixed dentition. 1502 83

Several works showed a decreased role for occlusion in the etiology of temporomandibular disorders (TMD). Nonetheless, it may be hypothesized that occlusion acts as a modulator through which bruxism activities may cause damage to the stomatognathic structures. To test this hypothesis, a logistic regression model was created with the inclusion of clinically diagnosed bruxism and eight occlusal features as potential predictors for temporomandibular joint (TMJ) pain in a sample of 276 consecutive TMD patients. The final logit showed that the percentage of the total log likelihood for TMJ pain explained by the significant factors was small and amounted to 13.2%, with unacceptable levels of sensitivity (16.4%). The parameters overbite > or = 4 mm combined with clinically diagnosed bruxism [OR (odds ratio) 4.62], overjet > or = 5 mm (OR 2.83), and asymmetrical molar relationship combined with clinically diagnosed bruxism (OR 2.77) were those with the highest odds for disease, even though none of those values was significant with respect to confidence intervals. Thus, the hypothesis under evaluation has to be rejected. It is possible that future studies with a higher discriminatory power for the different bruxism activities might be indicated to get deeper into the analysis of the potential mechanisms through which occlusion may play a role, even if small, in the etiology of the different TMD.
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PMID:Predictive value of combined clinically diagnosed bruxism and occlusal features for TMJ pain. 2049 Dec 32

Many species of fish process their prey with cyclic jaw motions that grossly resemble those seen in mammalian mastication, despite starkly different tooth and jaw morphologies. The degree of similarity between the processing behaviors of these disparate taxa has implications for our understanding of convergence in vertebrate feeding systems. Here, we used XROMM (X-ray reconstruction of moving morphology) to investigate prey processing behavior of Potamotrygon motoro, the ocellate river stingray, which has recently been found to employ asymmetrical, shearing jaw motions to break down its prey. We found that P. motoro modulates its feeding kinematics to produce two distinct types of chew cycles: compressive cycles and overbite cycles. The latter are characterized by over-rotation of the upper jaw relative to the lower jaw, past the expected occlusal limit, and higher levels of bilateral asymmetry as compared with compressive chews. We did not find evidence of the mediolateral shearing motions typical of mammalian mastication, but overbite cycles appear to shear the prey item between the upper and lower toothplates in a propalinal fashion. Additionally, comparison of hyomandibular and jaw motions demonstrates that the angular cartilages decouple jaw displacement from hyomandibular displacement in rostrocaudal and mediolateral directions. The multiple similarities between mammalian mastication and the dynamic processing behavior of P. motoro support the use of sub-family Potamotrygoninae as a model for studying evolutionary convergence of mastication-like processing.
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PMID:Shearing overbite and asymmetrical jaw motions facilitate food breakdown in a freshwater stingray, Potamotrygon motoro. 3129 13