Micro-Computed Tomography Applications in Dentistry

Micro-computed tomography (MCT) encompasses two primary scanning options: ex-vivo and in-vivo imaging. Ex-vivo scanning involves the examination of extracted teeth or dental specimens, allowing for detailed analyses of the microarchitecture of mineralized tissue. By analyzing the microarchitecture of dental tissues, MCT can provide valuable information about bone density, porosity, and microstructural changes, contributing to a better understanding of disease progression and treatment outcomes. Moreover, MCT facilitates the quantification of dental parameters, such as bone volume, trabecular thickness, and connectivity density, which are crucial for evaluating the efficacy of dental interventions. This present study aims to comprehensively review and explore the applications of MCT in dentistry and highlight its potential in advancing research and clinical practice. The results depicted that the quantitative approach of MCT enhances the precision and reliability of dental research. Researchers and clinicians can make evidence-based decisions regarding treatment strategies and patient management, relying on quantifiable data provided by MCT. The applications of MCT in dentistry extend beyond research, with potential clinical implications in fields such as dental implantology and endodontics. MCT is expected to play an increasingly significant role in enhancing our understanding of dental pathologies, improving treatment outcomes, and ultimately, benefiting patient care in the field of dentistry.

Changes in the crown angulation and dental arch widths after nonextraction orthodontic treatment: Model analysis of mild crowding with high canines

This study was undertaken to examine which factors contributed to the correction of crowding in two patients who underwent nonextraction orthodontic treatment. A study model analysis was conducted to determine the effects of the orthodontic treatment for crowding with high canines on crown angulation and dental arch width in two patients. The results showed that the crown angulation was significantly increased, indicating distal tipping in the maxillary dental arch. This tendency was most commonly observed in the premolars among the lateral teeth. With respect to the dental arch width, the largest change was evident in the first molar and first premolar regions in cases 1 and 2, respectively. On the basis of these results, up-righting of mesially tipped lateral teeth and expansion of narrow dental arches could prove to be the keys to the success of space regaining or correction of high canines and mild crowding.

Comparison of Congenital Tooth Deficiencies Seen in Permanent Teeth in Individuals with Unilateral Cleft Lip and Palate to Those without Cleft Lip and Palate

Objective: To compare the congenital tooth deficiencies seen in permanent dentition in individuals with unilateral cleft lip and palate (UCLP) to non-cleft individuals with Angle Class I malocclusion. Method: The study was performed on orthopantomograph films of 50 individuals with UCLP aged between 12 - 16 years and 50 individuals with Angle Class I malocclusion individuals aged between 13 - 15 years. Individuals with UCLP;32 clefts were on the left side and 18 clefts were on the right side. Permanent third molar teeth deficiency was excluded from the study. Results: In 50 individuals with UCLP;35 (70%) upper lateral incisors were congenitally deficient in the cleft area, while 15 (30%) missing lateral teeth were found in the non-cleft side. In control group, 12 (24%) of 50 patients had congenital lateral incisor deficiency. Congenital deficiency of upper lateral incisor in UCLP;the cleft area was higher than the non-cleft side (p < 0.01). The difference was statistically important when compared with the control group (p < 0.001). In 50 individuals with UCLP;while 27 (54%) of second premolar teeth were congenitally deficient in cleft side, 23 (46%) were missing in non-cleft side. In control group, 18 (36%) congenital second premolar deficiency was detected. However, second premolar congenital deficiency was higher in UCLP group when compared to control group (p < 0.01). Conclusion: The deficiency of the lateral incisors in the cleft side is more often congenitally deficient than upper second premolar teeth and this should be considered in the treatment planning from an early age.

Cone beam computed tomographic evaluation of pharyngeal airway in North Indian children with different skeletal patterns

BACKGROUND In growing patients with skeletal discrepancies,early assessment of functional factors can be vital for the restoration of normal craniofacial growth.AIM To compare airway volumes in patients with mandibular retrognathism with the normal anteroposterior skeletal relationship,thereby assessing the association between cephalometric variables and airway morphology.METHODS Cone-beam computed tomography volume scans,and lateral cephalograms,3-dimensional airway volume and cross-sectional areas of 120 healthy children(54 boys and 66 girls mean age 15.19±1.28)which were done for orthodontic assessment were evaluated.The subjects were divided into 2 groups based on the angle formed between point A,Nasion and point B(ANB)values and cephalometric variables(such as anterior and posterior facial height,gonial angle etc.)airway volumes,and cross-sectional measurements were compared using independent t tests.Pearson’s correlation coefficient test was used to detect any relationship of different parts of the airway and between airway volume and 2-dimensional cephalometric variables.RESULTS Means and standard deviations for cephalometric,cross-sectional,and volumetric variables were compared.ANB,mandibular body length and facial convexity were statistically highly significant(P<0.01)whereas condylion to point A,nasal airway and total airway volume(P<0.05)were statistically significant.The nasal airway volume and the superior pharyngeal airway volume had a positive correlation(P<0.01),nasal airway was correlated to middle(P<0.05)and total airway superior had a relation with middle(P<0.05),inferior and total airway(P<0.05),middle was related to all other airways;inferior was also related to all the airways except nasal.Lateral cephalometric values were positively correlated with the airway volume with Frankfurt Mandibular Plane Angle and facial convexity showed significant correlations with total airway volume(P<0.05).Additionally,ANB angle was significantly correlated with total airway volume and superior airway(P<0.05).CONCLUSION The mean total airway volume in patients with retrognathic mandible was significantly smaller than that of patients with a normal mandible.

一种新的X线技术及其在口腔正畸中的应用——介绍X线头影测量技术

X线头影测量由Dr.Broadbent发明 ,他在 1931年美国Angle正畸学杂志上发表了第一篇介绍X线头影测量的论文。X线头影测量对于口腔正畸临床诊断、设计以及作为研究手段的重要作用 ,促进口腔正畸学科发展的事实是无可争议的 ,我国X线头影测量的研究应用起始于上世纪 6 0年代初 ,第一篇有关文章见于 196 5年第四期的北京医科大学学报 ,虽然起步较晚但发展很快至今也已步入与国际接轨的数字化高科技X线头影测量时代。今年是Dr.Broadbent有关X线头影测量论文发表 70周年 ,为了纪念他对口腔正畸学科发展的贡献 ,在此全文刊出他的这一论文。在论文刊出过程中得到了Dr.Broadbent之子Dr.H .Broadbentjr的授权和支持 。