The purpose of this study was to analyze and compare the differences in chewing efficiency among patients with different vertical skeletal types of Angle Class I and Angle Class II malocclusions, to ...provide reference for orthodontic clinical practice.
Sample size estimation revealed a minimum of 53 for each class. Thus, a total of 108 patients with Angle Class I and Angle Class II malocclusions were selected. Lateral skull radiographs were taken, and head measurements were analyzed via geometric tracing software. Chewing efficiency was measured using the gravimetric method to compare between the two groups. The vertical skeletal pattern was classified via Steiner analysis.
Significant statistical differences in chewing efficiency were observed between patients presenting with Angle Class I and Angle Class II malocclusions (P < .05). Additionally, significant differences in chewing efficiency were observed among patients with different vertical skeletal patterns (P < .05). Furthermore, a statistically significant difference in chewing efficiency was found between men and women (P < .05).
Patients with Angle Class I malocclusions exhibited significantly higher chewing efficiency compared to those with Angle Class II malocclusions. Among patients with different vertical facial types, the chewing efficiency followed the order of low angle > normal angle > high angle. Moreover, men demonstrated a higher chewing efficiency than women.
To test the null hypothesis that the presence of dehiscence and fenestration was not different among patients with skeletal Class I, II, and III malocclusions.
In this retrospective study, a total of ...123 cone-beam computed tomography (CBCT) images were obtained with an iCAT scanner (Imaging Sciences International, Hatfield, Pa). Patients with normal vertical patterns were classified according to dental malocclusion and ANB angle. Class I comprised 41 patients-21 girls and 20 boys (mean age, 22.4 ± 4.5 years); Class II comprised 42 patients-22 girls and 20 boys (mean age, 21.5 ± 4.2 years); and Class III comprised 40 subjects-22 girls and 18 boys (mean age, 22.1 ± 4.5 years). A total of 3444 teeth were evaluated. Analysis of variance and Tukey's test were used for statistical comparisons at the P < .05 level.
Statistical analysis indicated that the Class II group had a greater prevalence of fenestration than the other groups (P < .001). No difference was found in the prevalence of dehiscence among the three groups. Although fenestration had greater prevalence in the maxilla, more dehiscence was found in the mandible for all groups. In Class I, alveolar defects (dehiscence, fenestration) were matched relatively in both jaws. Furthermore, Class II and Class III subjects had more alveolar defects (41.11% and 45.02%, respectively) in the mandible. Dehiscences were seen with greater frequency in the mandibular incisors of all groups.
The null hypothesis was rejected. Significant differences in the presence of fenestration were found among subjects with skeletal Class I, Class II, and Class III malocclusions. Fenestrations had greater prevalence in the maxilla, but more dehiscences were found in the mandible.
An accurate anteroposterior measurement of jaw relationships is critically important in orthodontic diagnosis and treatment planning. The angular and linear measurements that have been proposed can ...be inaccurate because they depend on various factors. The purpose of this study was to establish a new cephalometric measurement, named the Beta angle, to assess the sagittal jaw relationship with accuracy and reproducibility. This angle uses 3 skeletal landmarks—point A, point B, and the apparent axis of the condyle—to measure an angle that indicates the severity and the type of skeletal dysplasia in the sagittal dimension. Seventy-six pretreatment cephalometric radiographs of white patients were selected on the basis of 4 criteria that indicate a normal Class I skeletal pattern; the mean and the SD for the Beta angle were calculated. This group was compared with Class II and Class III skeletal pattern groups. After using the 1-way analysis of variance and the Newman-Keuls test and running receiver-operating-characteristics curves, we obtained results that showed that a patient with a Beta angle between 27° and 35° can be considered to have a Class I skeletal pattern. A more acute Beta angle indicates a Class II skeletal pattern, and a more obtuse Beta angle indicates a Class III skeletal pattern.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
To compare craniofacial and cervical morphology between skeletal Classes II and III applying Geometric Morphometric Methods (GMM). Twenty-six cervical and craniofacial landmarks of 40 Class II and 39 ...Class III individuals were digitalized on lateral cephalograms. Procrustes ANOVA, generalized Procrustes, principal component analyses, and thin-plate spline function were applied to assess the pattern of shape variation of craniofacial structure and the cervical spine in relation to skeletal classes. Compared with Class III, Class II individuals presented a maxillary protrusion, mandibular retrusion, shorter mandibular corpus, posterior mandibular ramus rotation, anterior cranial base rotation, and a smaller centroid size. Furthermore, a forward and smaller cervical spine were observed. With GMM, the shape and size differences between skeletal classes can be analyzed visually and numerically.
Unilateral posterior crossbite is a problem often seen in orthodontic practice, and properly understanding chewing patterns will lead to the most effective treatment program. Drawing on their ...research and available literature, Drs. Piancino and Kyrkanides present a fascinating look at chewing cycles and their role in the functional treatment of unilateral posterior crossbite. * Describes the physiology and pathology of chewing patterns and muscular activation in humans * Explains chewing patterns and muscular coordination, and their influence on the growth and harmony of the stomatognathic system * Clinical instruction for checking and correcting masticatory function and functional asymmetry in order to prevent the relapse of the malocclusion * Clinical cases walk readers through the treatment of seven crossbites
Angle, Tweed, and Moyers classified Class III malocclusions into 3 types: pseudo, dentoalveolar, and skeletal. Clinicians have been trying to identify the best timing to intercept a Class III ...malocclusion that develops as early as the deciduous dentition. With microimplants as skeletal anchorage, orthopedic growth modification became more effective, and it also increased the scope of camouflage orthodontic treatment for patients who were not eligible for orthognathic surgery. However, orthodontic treatment combined with orthognathic surgery remains the only option for patients with a severe skeletal Class III malocclusion or a craniofacial anomaly. Distraction osteogenesis can now be performed intraorally at an earlier age. The surgery-first approach can minimize the length of time that the malocclusion needs to worsen before orthognathic surgery. Finally, the use of computed tomography scans for 3-dimensional diagnosis and treatment planning together with advances in imaging technology can improve the accuracy of surgical movements and the esthetic outcomes for these patients.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Summary
Background
Temporomandibular Disorders (TMD) is a multifactorial condition, which could be associated to occlusal and psychological factors, such as anxiety.
Objective
Investigate if anxiety ...and malocclusion are associated with the prevalence of TMD in adolescents.
Methods
To ensure a population‐based representative sample, 934 adolescents aged 10 to 14 years old from Curitiba‐PR, Brazil were randomly selected and examined according to Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) and malocclusion by a single‐calibrated examiner (Kappa > 0.80). Anxiety was assessed according to trait anxiety (STAI‐T), categorised as high, moderate and low levels. For occlusal exam, it was considered: Angel's molar relationship, anterior and posterior crossbite, excessive overjet, open and deep bite. The associations were analysed by the crude and adjusted prevalence ration (RPa) of TMJ, calculated by a Poisson multivariate regression with robust variance (α = 0.05).
Results
The prevalence of at least one type of malocclusion was found in 52.3%. Anxiety was found in high level (12.2%), moderate (70.4%) and low (17.5%). Presence of high anxiety was significantly associated with the prevalence of TMD symptoms (RPa = 4.06, P < 0.001), as well as the prevalence of myofascial pain (RPa = 24.78; P < 0.001) and prevalence of disc displacement with reduction (RPa = 11.08, P < 0.001). Adolescents Class II had higher prevalence of myofascial pain (Class II RPa = 1.73; P < 0.015) than adolescents Class I. Adolescents Class III presented higher prevalence of myofascial pain (PRa 2.53; P = 0.004) than adolescents Class I.
Conclusion
Anxiety is strongly associated with TMD in adolescents. Presence of Class II or III is associated with higher prevalence of myofascial pain in adolescentsPLESAE check and approve the edit made in the article title.
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BFBNIB, CMK, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Objective
To investigate SNPs in bone‐ and cartilage‐related genes and their interaction in the aetiology of sagittal and vertical skeletal malocclusions.
Settings and sample population
This study ...included 143 patients and classified as follows: skeletal class I (n = 77), class II (n = 47) and class III (n = 19); maxillary retrusion (n = 39), protrusion (n = 52) and well‐positioned maxilla (n = 52); mandibular retrognathism (n = 50), prognathism (n = 50) and well‐positioned mandible (n = 43); normofacial (n = 72), dolichofacial (n = 55) and brachyfacial (n = 16).
Materials and methods
Steiner's ANB, SNA, SNB angles and Ricketts’ NBa‐PtGn angle were measured to determine the skeletal malocclusion and the vertical pattern. Nine SNPs in BMP2, BMP4, SMAD6, RUNX2, WNT3A and WNT11 were genotyped. Chi‐squared test was used to compare genotypes among the groups. Multifactor dimensionality reduction (MDR) and binary logistic regression analysis, both using gender and age as co‐variables, were also used. We performed Bonferroni correction for multiple testing.
Results
Significant associations at P < .05 were observed for SNPs rs1005464 (P = .042) and rs235768 (P = .021) in BMP2 with mandibular retrognathism and for rs59983488 (RUNX2) with maxillary protrusion (P = .04) as well as for rs708111 (WNT3A) with skeletal class III (P = .02; dominant model), rs1533767 (WNT11) with a brachyfacial skeletal pattern (P = .01, OR = 0.10; dominant model) and for rs3934908 (SMAD6) with prognathism (P = .02; recessive model). After the Bonferroni correction, none of the SNPs remained associated. The MDR predicted some interaction for skeletal class II, dolichofacial and brachyfacial phenotypes.
Conclusion
Our results suggest that SNPs in BMP2, BMP4, SMAD6, RUNX2, WNT3A and WNT11 could be involved in the aetiology of sagittal and vertical malocclusions.
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CMK, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Caudal malocclusions in cats may result in a variety of traumatic lesions affecting the soft tissues of the ipsilateral mandible such as fovea, gingival cleft, and proliferative lesions. Fifty-one ...cats diagnosed with a traumatic caudal malocclusion were compared with a control hospital population and evaluated for prevalence with respect to breed and sex. Twenty-two cats that were treated had radiographic, clinical findings, and the outcome of treatment (extraction or odontoplasty) recorded. Maine Coon, Persian, and male neutered cats were overrepresented while Domestic Shorthairs were underrepresented within the study population. Radiographically, 50% of the fovea lesions had an area of decreased bone density in the region of the lesion and none of these had evidence of periodontal disease. All gingival cleft lesions had radiographic changes consistent with periodontal disease. 15.4% of proliferative lesions presented with radiographic changes, with only half of those presenting with both radiographic and clinical evidence of periodontal disease. Eleven cats were treated by odontoplasty and eleven by extraction. One cat treated by odontoplasty developed new lesions caudally, and another had persistence of the initial lesions. Two cats in the extraction group developed new lesions rostral to the extracted teeth. In most instances, odontoplasty or extraction resulted in successful soft tissue lesion resolution. In rare cases, additional treatment was necessary due to either persistence or development of new lesions.
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CMK, NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
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