Fenestration and dehiscence defects in maxillary anterior teeth using two classification systems

Does crown, root, and bone visualization in a clear aligner virtual setup impact treatment decisions?

INTRODUCTION

Clear aligner technology based on a machine learning algorithm is currently available for orthodontic treatment. Treatment planning on the basis of 3-dimensional crown, root, and bone imaging is claimed to provide accurate diagnosis and better treatment outcomes for adult patients with complex needs. This study aimed to answer the following questions: (1) would practitioners modify their original treatment plan once provided with the crown, root, and bone view? and (2) does practitioner satisfaction regarding treatment outcomes change once the crown, root, and bone view is provided?

METHODS

An online questionnaire was emailed to members of the American Association of Orthodontists (n = 2300) and the Virginia Orthodontic Education and Research Foundation (n = 211). The survey consisted of videos of 4 patients shown in 2 presentations: crown-only and crown, root, and bone views, generated by artificial intelligence-driven treatment planning software (3D Predict aligner system; 3D Predict, New York, NY). Respondents were asked to answer treatment-related questions and rate the treatment outcomes using a visual analog scale. Statistical analyses were completed to determine the significance of crown, root, and bone view on treatment planning with clear aligners.

RESULTS

A total of 70 orthodontists participated in the survey. There were significant differences in responses when viewing patients in crown-only and crown, root, and bone presentations. Across the 4 patients, 33%-43% of practitioners changed their sentiment toward the treatment plan (P <0.001). When rating satisfaction on the 100-point scale, average ratings changed by 10.6 to 21.0 points; both increases and decreases in satisfaction were seen across the patients (P <0.001).

CONCLUSIONS

When given 3-dimensional information on the position of a patient's crowns, root, and bone coverage, orthodontists are likely to change their clear aligner treatment plan. This study showed that a confirmation of dehiscence and fenestrations using the root and bone view resulted in practitioner dissatisfaction despite an initial satisfaction with the crown-only view.

Smokeless tobacco and periodontitis: A systematic review with meta-analysis

AIM

The present systematic review with meta-analysis aimed to investigate the global association between smokeless tobacco (SLT) use and periodontitis, considering significant effect size variation based on the income levels of countries.

METHODS

We searched seven databases to identify studies that assessed the prevalence of periodontitis in adult SLT users compared to non-users. The quality of studies was evaluated using the 10-item risk-of-bias tool, and publication bias was addressed through the trim-and-fill method. Sensitivity analysis utilized the leave-one-out approach. Meta-analysis and meta-regression, stratified by country income, SLT type, and smoking status, employed robust variance estimation.

RESULTS

From an initial pool of 484 studies, 29 studies met the selection criteria and were subjected to qualitative synthesis. Subsequently, data from 19 studies were included in the meta-analysis. SLT users exhibited a nearly threefold greater likelihood of periodontitis compared to non-users (OR = 2.99; 95% CI: 2.10, 4.27; p < .01). The pooled estimate did not vary significantly based on the type of SLT used or concurrent smoking. However, the odds of periodontitis varied according to the economic level of the country; the pooled estimate was higher in high-income countries (OR = 1.69; 95% CI: 1.20, 2.37; p < .01) and even higher in lower-middle-income and lower-income countries (OR = 3.91; 95% CI: 2.66, 5.77; p < .01).

CONCLUSIONS

Smokeless tobacco users have a higher likelihood of developing periodontitis. This study underscores global disparities in the SLT-periodontitis relationship, highlighting the need for targeted interventions, particularly in economically challenged areas where SLT use is largely unregulated.

Correlation between Tooth Position Parameters and Apical Fenestration: A Cone-Beam Computed Tomography Study

This study aimed to assess the relationship between apical fenestration-a defect in the alveolar bone involving the root apex-and tooth position in all tooth groups, excluding the third molars, utilizing cone-beam computed tomography (CBCT) images. A total of 800 CBCT scans (400 maxillary and 400 mandibular) from patients undergoing various treatments were examined by a single professional (radiologist and endodontist). Statistical analyses, including the chi-square test or Fisher's exact test, were conducted using R software 2.7.3 (R Foundation, Vienna, Austria). Results indicated a significant association (p ≤ 0.05) between apical fenestration and tooth position. In the upper teeth, apical fenestrations were notably present in the mesio-buccal (17.17%) and disto-buccal (11.07%) roots of the first molars. Conversely, apical fenestrations in the lower teeth were relatively less frequent. The study revealed a negative correlation between apical fenestration and mesial inclination, rotation, and extrusion in the upper teeth. However, a positive correlation was observed between apical fenestration and lingual inclination in the upper teeth. In conclusion, this study illuminates the distribution of apical fenestration and its correlation with tooth positions, offering insights into factors influencing this defect in dental anatomy. The findings enhance our understanding of nuanced relationships between tooth position and apical fenestration in the upper and lower dental arches.

Fenestration and Dehiscence in Human Maxillary Alveolar Bone: An In Silico Study Using the Finite Element Method

INTRODUCTION

Fenestration and dehiscence are alveolar bone defects. Although not considered a pathology, these alveolar bone defects end up influencing dental treatment, such as surgeries, mainly periodontal, and therefore must be considered during treatment planning. However, currently, little is known about the biomechanical origin of these bone formations. The aim of the study was to use the finite element method (FEM) to test hypotheses of predictive factors for fenestrations and dehiscence in human alveolar bone.

METHODS

A FEM simulation of the action of functional, parafunctional, and orthodontic occlusal loads on the upper central incisor and upper canine was performed. For the simulation, a three-dimensional model of an adult human skull, fully dented and with intact bone structure, was constructed from computed tomography images. The buccal alveolar bone lamina was evaluated considering the calculation of equivalent stresses, as well as maximum principal stresses.

RESULTS

The action of functional and parafunctional forces on the incisal edges and the orthodontic force on the buccal face of the upper central incisor and upper canine teeth generated tensions at different levels of magnitude in the buccal bone lamina, varying in regions, at all levels of strength. Changing levels of force magnitude resulted in variations in relation to the level of deformation.

CONCLUSION

The computational simulation using the FEM was able to identify a difference in stress in the alveolar bone tissue in each of the applied forces. The difference in stresses obtained may suggest the formation of dehiscence or fenestration in the region studied.