44 research outputs found
Condylar degeneration in patients with dental open bite versus skeletal open bite utilizing CBCT
Idiopathic condylar resorption (ICR) is a condition in which either one or both condyles undergo degeneration. Bilateral TMJ involvement presents as a clockwise rotation of the mandible in the posterior-inferior direction, resulting in an anterior open bite. The purpose of the study was to assess TMJ condylar degeneration in dental open bites compared to skeletal open bites
Changes in cephalometric measurements in adult patients following orthodontic treatment with premolar extractions versus non-extraction
Extraction of premolars is indicated as part of orthodontic treatment for patients who have severe crowding or protrusion of incisors. CBCT can be used to locate cephalometric landmarks in 3D. The purpose of this study was to determine whether there are differences in sagittal, transverse, and vertical skeletal and dental dimensions for adult patients who were treated with premolar extractions in conjunction with orthodontic treatment compared to those who received orthodontic treatment without extractions
Vertical Dimensions of Mandible in Class II Subdivision Malocclusion with Skeletal Asymmetry
• Advancements in 3-dimensional imaging analysis, utilizing cone-beam computed tomography (CBCT), have allowed for further investigation of skeletal asymmetry. • While past 2-dimensional studies attributed dentoalveolar deviation to unilateral Class II malocclusion, recent 3D studies have found a primarily skeletal contribution.1 • There is much debate on the impact of condylar morphology on malocclusion in patients with Class II subdivision and significant skeletal asymmetry.2 • Some authors concluded that condylar characteristics are not correlated with skeletal asymmetry, while others reported a correlation between a greater condyle angulation and skeletal asymmetry.2-
Airway dimension change after open bite treatment – 3D CBCT study
â—Ź Studies have shown that airway dimension can be correlated to skeletal/dental malocclusion, including anterior open bites.1 â—Ź Counter-clockwise rotation of mandible or extrusion of incisors can be used to correct anterior open bites; however, their subsequent effect on airway dimension has not been well studied. â—Ź Studies have shown that both the inferior oropharyngeal airway volume and cross-sectional area increased as the mandibular position is advanced forward (decreased mandibular plane angle).2 â—Ź Previous 3D MRI studies have shown that total airway volume, retropalatal and retroglossal airway volume increased following open bite closure.
Evaluation of Skeletal and Dental Asymmetries in Patients with Angle Class II Subdivision Malocclusion with 3-Dimensional Analysis of Cone-Beam Computed Tomography
• Dentofacial asymmetries can present substantial challenges to orthodontic treatment.1 They, which can be congenital, developmental, and acquired, are based on discrepancies in the two halves of the face with reference to size, form, and arrangement of facial landmarks. • Class II subdivision malocclusions show more than half-step Class II occlusion on one side of the dental arch and Class I molar occlusion on the other side of the dental arch. They attribute to 50% of all Class II malocclusions and are one of the most frequent dental asymmetries in the orthodontic population.2 • Cone-beam computed tomography (CBCT) can be used to examine skeletal and dental asymmetries in Class II subdivision malocclusions and other morphological features of the craniofacial structures of facial asymmetry.3 • Mandibular asymmetry (skeletal) was the primary factor that contributed to Angle Class II subdivision malocclusions. Class II side had shorter total mandibular length and ramus height and deviated mandibular dental midline landmarks (pogonion and menton). Mandibular dental landmarks were positioned more latero-posterio-superiorly.
Parameters affecting mechanical and thermal responses in bone drilling: A review
Surgical bone drilling is performed variously to correct bone fractures, install prosthetics, or for therapeutic treatment. The primary concern in bone drilling is to extract donor bone sections and create receiving holes without damaging the bone tissue either mechanically or thermally. We review current results from experimental and theoretical studies to investigate the parameters related to such effects. This leads to a comprehensive understanding of the mechanical and thermal aspects of bone drilling to reduce their unwanted complications. This review examines the important bone-drilling parameters of bone structure, drill-bit geometry, operating conditions, and material evacuation, and considers the current techniques used in bone drilling. We then analyze the associated mechanical and thermal effects and their contributions to bone-drilling performance. In this review, we identify a favorable range for each parameter to reduce unwanted complications due to mechanical or thermal effects
COMPARISON OF SKELETAL AND DENTAL DIFFERENCES BETWEEN CLASS I AND CLASS II SIDES AND THEIR RELATIONSHIP WITH ASYMMETRIC MOLAR RELATIONSHIPS IN CLASS II SUBDIVISION MALOCCLUSIONS – A CBCT STUDY
Introduction: The purpose of this study is to compare dental and skeletal differences between Class I and Class II sides and their contributions to the degree of asymmetric molar relationship in Class II subdivision malocclusions using CBCT.
Methods: One hundred and eight patients presenting with Angle Class II subdivision malocclusions (mean age =21.05 years) were assessed with 3-dimensional cone-beam computed tomography scans. Paired t-tests were used to compare linear skeletal, angular and dental measurement differences between Class I and Class II sides. Correlations of linear skeletal, angular and dental measurement differences between Class I and Class II sides were made against the Asymmetric Molar Relationship measurement. Differences between Class I and Class II sides were correlated to the degree of skeletal asymmetry, as defined by defined as menton deviation from mid-sagittal plane.
Results: Maxillary first molar position was more mesially positioned on the Class II side and the mandibular first molar position was more distally positioned on the Class II side. No significant skeletal differences were found between Class I and Class II sides. Asymmetric Molar Relationship was correlated with a more mesially positioned maxillary first molar position and distally positioned mandibular first molar position on the Class II side. There were no significant skeletal differences that were correlated significantly with the Asymmetric Molar Relationship.
Conclusion: In a sample of one hundred and eight patients exhibiting Class II subdivision malocclusion with and without skeletal asymmetry, the Class I and Class II sides display differences that are mainly dentoalveolar in nature. The degree of molar relationship asymmetry was correlated with a more a mesially positioned maxillary molar and a more distally positioned mandibular molar on the Class II side. There were no significant skeletal differences between Class I and Class II sides and no significant skeletal contributions to molar asymmetry
COMPARISON OF SKELETAL AND DENTAL DIFFERENCES BETWEEN CLASS I AND CLASS II SIDES AND THEIR RELATIONSHIP WITH ASYMMETRIC MOLAR RELATIONSHIPS IN CLASS II SUBDIVISION MALOCCLUSIONS – A CBCT STUDY
Introduction: The purpose of this study is to compare dental and skeletal differences between Class I and Class II sides and their contributions to the degree of asymmetric molar relationship in Class II subdivision malocclusions using CBCT.
Methods: One hundred and eight patients presenting with Angle Class II subdivision malocclusions (mean age =21.05 years) were assessed with 3-dimensional cone-beam computed tomography scans. Paired t-tests were used to compare linear skeletal, angular and dental measurement differences between Class I and Class II sides. Correlations of linear skeletal, angular and dental measurement differences between Class I and Class II sides were made against the Asymmetric Molar Relationship measurement. Differences between Class I and Class II sides were correlated to the degree of skeletal asymmetry, as defined by defined as menton deviation from mid-sagittal plane.
Results: Maxillary first molar position was more mesially positioned on the Class II side and the mandibular first molar position was more distally positioned on the Class II side. No significant skeletal differences were found between Class I and Class II sides. Asymmetric Molar Relationship was correlated with a more mesially positioned maxillary first molar position and distally positioned mandibular first molar position on the Class II side. There were no significant skeletal differences that were correlated significantly with the Asymmetric Molar Relationship.
Conclusion: In a sample of one hundred and eight patients exhibiting Class II subdivision malocclusion with and without skeletal asymmetry, the Class I and Class II sides display differences that are mainly dentoalveolar in nature. The degree of molar relationship asymmetry was correlated with a more a mesially positioned maxillary molar and a more distally positioned mandibular molar on the Class II side. There were no significant skeletal differences between Class I and Class II sides and no significant skeletal contributions to molar asymmetry
The ABC’s of a Multidisciplinary Approach to Diagnosis and Treatment of Dental Cases
Increase your knowledge of how to integrate and apply various disciplines in the diagnosis and designing of a treatment plan. During this interactive course, the speakers will present cases from the medical-dental, anatomic, orthodontic and pain management/psychological points of view with relevance to practicing general dentists, specialists and their teams. Cases will be presented, then analyzed and discussed among the participants. The presenters will lead the discussion through to a diagnostic conclusion, treatment design and implementation strategy.
Participants will leave the course with a deeper and broader understanding of diagnosis and treatment design.
You Will Learn The most common medical problems, system disorders and potential drug interactions encountered in practice and how they might modify dental treatment decisions The anatomy of the oromaxillofacial region and how it relates to diagnosis and treatment The role of orthodontic treatment in the multidisciplinary approach to redistribute spaces (open or close) for implant/bridge restoration Diagnosis of orofacial lesions and TMD dysfunctions and how this affects dentistry The important role each member of the dental team plays in communicating and delivering the proposed treatment to the patient
Who Should Attend
This course is designed for dentists, specialists and allied dental professionals
1 Long Term Impact of Microimplant Assisted Rapid Palatal Expansion on Soft Tissue Nasal Morphology
Introduction: When skeletal transverse discrepancies exist between the maxilla and mandible, they commonly manifest in dental malocclusion. If left uncorrected, the malocclusion can lead to periodontal issues, tooth fractures, tooth loss, or other significant dental problems. Utilization of microimplants in palatal expansion aims to correct transverse discrepancies between the maxilla and mandible by separating the palatal suture in a parallel manner aimed at maximizing skeletal changes and minimizing dental side effects. Overlying soft tissue changes can be affected by the induced skeletal changes. The purpose of this study is to evaluate skeletal expansion and the overlying soft tissue change that occurs using MARPEs (microimplant assisted rapid palatal expanders) at the end of orthodontic treatment in skeletally mature (Cervical Vertebral Maturation (CMV) ≥ 5) patients using cone-beam computed tomography (CBCT) imaging and to evaluate soft tissue changes that occur at the time of orthodontic treatment completion using CBCT imaging. Materials and Methods: CBCT scans from 19 patients who were treated using microimplant assisted rapid palatal expanders were traced and evaluated at three time points: Before orthodontic treatment (T1), post MARPE expansion with MARPE in place (T2), and after orthodontic treatment with MARPE removed. Fourteen hard tissue landmarks and six soft tissue landmarks in the midface and nasal cavity regions were traced by three judges at each time point. The traced landmark points were averaged among all three judges and comparisons were made between the three time points to see the amount of expansion that occurred at various anatomical 2 regions. Intraclass correlation coefficient (ICC) was used to evaluate inter-judge reliability for all measurements. A repeated measures ANOVA test was used for statistical comparison across all three time points and a Tukey post hoc test was used for comparison between time points. Significance was set to .05 and ICC was set to \u3e.70. Results: Expansion with microimplant assisted rapid palatal expanders can affect the hard tissue of the midface region as well as the overlying soft tissue. Increases in skeletal width from the ANS down to the maxillary alveolar bone were statistically significant in both the short term (T1-T2) and long term (T1-T3). The nasal cavity width at inferior turbinate area increased significantly after expansion (T2) and remained increased at treatment completion (T3) and the increased soft tissue width of the alar base that presented after expansion therapy remained increased at treatment completion. Conclusion: Maxillary expansion with microimplant assisted expanders resulted in skeletal changes throughout the maxilla and led to a significant long-term increase in nasal cavity width. The soft tissue changes associated with MARPE treatment show that a widening of the base of the nose may be expected after expansion and can remain at treatment completion