Influence of growth structures and fixed appliances on automated cephalometric landmark recognition with a customized convolutional neural network.

BACKGROUND: One of the main uses of artificial intelligence in the field of orthodontics is automated cephalometric analysis. Aim of the present study was to evaluate whether developmental stages of a dentition, fixed orthodontic appliances or other dental appliances may affect detection of cephalometric landmarks. METHODS: For the purposes of this study a Convolutional Neural Network (CNN) for automated detection of cephalometric landmarks was developed. The model was trained on 430 cephalometric radiographs and its performance was then tested on 460 new radiographs. The accuracy of landmark detection in patients with permanent dentition was compared with that in patients with mixed dentition. Furthermore, the influence of fixed orthodontic appliances and orthodontic brackets and/or bands was investigated only in patients with permanent dentition. A t-test was performed to evaluate the mean radial errors (MREs) against the corresponding SDs for each landmark in the two categories, of which the significance was set at p < 0.05. RESULTS: The study showed significant differences in the recognition accuracy of the Ap-Inferior point and the Is-Superior point between patients with permanent dentition and mixed dentition, and no significant differences in the recognition process between patients without fixed orthodontic appliances and patients with orthodontic brackets and/or bands and other fixed orthodontic appliances. CONCLUSIONS: The results indicated that growth structures and developmental stages of a dentition had an impact on the performance of the customized CNN model by dental cephalometric landmarks. Fixed orthodontic appliances such as brackets, bands, and other fixed orthodontic appliances, had no significant effect on the performance of the CNN model.

Clinical performance of a new fissure sealant-results from a 2-year randomized clinical trial.

OBJECTIVES: The aim of this randomized clinical trial (RCT) was to explore the clinical survival of a new, Bis-GMA-free pit and fissure sealant (Helioseal F Plus) in comparison to an established control material (Helioseal F). MATERIAL AND METHODS: This in vivo study was designed as a prospective, 2-year, two-centre RCT with a split-mouth design. The initial study population consisted of 92 adolescents who were followed up 1 month (N = 89), 6 months (N = 88), 1 year (N = 85) and 2 years (N = 82) after sealant application. The attrition rate was 10.9% after 2 years. At each examination, the sealant retention and presence of caries were recorded. The statistical analysis included the calculation of Kaplan-Meier survival curves, log-rank tests and a Cox proportional hazard regression model. RESULTS: No adverse events during the application or any of the follow-up visits were documented. The proportion of completely intact sealants and those with minimal loss was almost identical in both groups at 85.9% (Helioseal F Plus) and 86.5% Helioseal F) after 2 years of observation. The regression analysis revealed operator dependency; no significant differences were found between the materials, the study centres, the chosen isolation technique and patient age or sex. CONCLUSION: The newly developed sealant can be evaluated as at least equivalent in terms of survival and retention behaviour compared to the established control material. CLINICAL RELEVANCE: The new sealant can be recommended for clinical use. With respect to the material properties (Bis-GMA-free, less light polymerisation time and better thixotropic behaviour), it offers additional advantages with clinical relevance.

Testing the association between tobacco smoking, alcohol consumption, and risk of periodontitis: A Mendelian randomization study.

AIM: To investigate the associations of tobacco smoking and alcohol consumption with periodontitis using Mendelian randomization (MR) analysis. MATERIALS AND METHODS: We used 17 single nucleotide polymorphisms (SNPs) as instrumental variables (IVs) for the number of cigarettes per day from a genome-wide association study (GWAS) of 337,334 individuals, 109 SNPs for a lifetime smoking index from GWAS of 462,690 participants, and 33 SNPs for the number of drinks per week from GWAS of 941,280 individuals. The periodontitis GWAS included 12,289 cases and 22,326 controls. Wald ratios were obtained by dividing the SNP-periodontitis effects by SNP-exposure effects and pooled using an inverse-variance weighted model. RESULTS: Genetic liabilities for higher number of cigarettes per day (odds ratio [OR] per one standard deviation (1SD) increment = 1.56; 95% CI: 1.18-2.07, p-value = .0018, Q-value = .0054), lifetime smoking index (OR per 1SD = 1.26; 95% CI: 1.04-1.53, p-value = .0161, Q-value = .0242), and drinks per week (OR per 1SD = 1.41; 95% CI: 1.04-1.90, p-value = .0265, Q-value = .0265) were associated with increased odds of periodontitis. Estimates were consistent across robust and multivariable MR analyses. CONCLUSIONS: The findings of this MR analysis suggest an association between tobacco smoking and alcohol consumption with periodontitis.

Comparison of four different treatment strategies in teeth with molar-incisor hypomineralization-related enamel breakdown-A retrospective cohort study.

BACKGROUND: There is little information available on the longevity of non-invasive glass ionomer cement (GIC) and composite restorations as well as conventional composite and ceramic restorations placed on permanent teeth with enamel breakdowns due to molar-incisor hypomineralization (MIH). AIM: To compare the longevity of the abovementioned treatment procedures. DESIGN: Of 377 identified MIH patients, 118 individuals received restorative treatment and were invited for clinical examination, including caries and MIH status. Finally, survival data from 204 MIH-related restorations placed on 127 teeth were retrospectively collected from 52 children, monitored between 2010 and 2018. Descriptive and explorative analyses were performed, including Kaplan-Meier estimators and the Cox regression model. RESULTS: The mean patient observation time was 42.9 months (SD = 35.1). The cumulative survival probabilities after 36 months-7.0% (GIC, N = 28), 29.9% (non-invasive composite restoration, N = 126), 76.2% (conventional composite restoration, N = 27) and 100.0% (ceramic restoration, N = 23)-differed significantly in the regression analysis. CONCLUSIONS: Conventional restorations were associated with moderate-to-high survival rates in MIH teeth. In contrast, non-invasive composite restorations, which were predominately used in younger or less cooperative children, were linked to lower survival rates.

Efficacy of platelet-rich fibrin in papilla reconstruction: A systematic review and meta-analysis.

This systematic review and meta-analysis aimed to compare the efficacy of using platelet-rich fibrin (PRF) or connective tissue graft (CTG) for papilla reconstruction in the treatment of black triangles. A comprehensive electronic search across PubMed, Cochrane, Web of Science, ProQuest, and Scopus was conducted to identify the relevant randomized-controlled trials (RCTs), cohort studies, and case series. Quality assessment and meta-analysis were performed using R Statistical Software, focusing on the parameters such as papilla height, gingival index, plaque index (PI), clinical attachment level (CAL), and pocket probing depth. Registration number: CRD42022322934. From 191 initial studies, 7 were eligible for full-text review, with 4 RCTs and one retrospective study included in the meta-analysis. The analysis favored CTG over PRF in terms of black triangle height at 3-6 months postsurgery and in PI improvement at 3 months. No significant differences were found in CAL and probing pocket depth. While PRF can yield satisfactory results in papilla augmentation, CTG demonstrates superior clinical outcomes in specific parameters. Further research with more extensive clinical data is warranted.

Bracket Transfer Accuracy with the Indirect Bonding Technique-A Systematic Review and Meta-Analysis.

PURPOSE: To investigate the bracket transfer accuracy of the indirect bonding technique (IDB). METHODS: Systematic search of the literature was conducted in PubMed MEDLINE, Web of Science, Embase, and Scopus through November 2021. SELECTION CRITERIA: In vivo and ex vivo studies investigating bracket transfer accuracy by comparing the planned and achieved bracket positions using the IDB technique were considered. Information concerning patients, samples, and applied methodology was collected. Measured mean transfer errors (MTE) for angular and linear directions were extracted. Risk of bias (RoB) in the studies was assessed using a tailored RoB tool. Meta-analysis of ex vivo studies was performed for overall linear and angular bracket transfer accuracy and for subgroup analyses by type of tray, tooth groups, jaw-related, side-related, and by assessment method. RESULTS: A total of 16 studies met the eligibility criteria for this systematic review. The overall linear mean transfer errors (MTE) in mesiodistal, vertical and buccolingual direction were 0.08 mm (95% CI 0.05; 0.10), 0.09 mm (0.06; 0.11), 0.14 mm (0.10; 0.17), respectively. The overall angular mean transfer errors (MTE) regarding angulation, rotation, torque were 1.13° (0.75; 1.52), 0.93° (0.49; 1.37), and 1.11° (0.68; 1.53), respectively. Silicone trays showed the highest accuracy, followed by vacuum-formed trays and 3D printed trays. Subgroup analyses between tooth groups, right and left sides, and upper and lower jaw showed minor differences. CONCLUSIONS AND IMPLICATIONS: The overall accuracy of the indirect bonding technique can be considered clinically acceptable. Future studies should address the validation of the accuracy assessment methods used.

3-Year Clinical Performance of a New Pit and Fissure Sealant.

The aim of this 3-year, randomized clinical trial (RCT) in split-mouth design was to explore the clinical survival of a Bis-GMA-free pit and fissure sealant (Helioseal F Plus) in comparison to a control material (Helioseal F). The initial population consisted of 92 adolescents. Follow-ups took place after one year (N = 85), two years (N = 82) and three years (N = 76) after application. At each examination, sealant retention and the presence of caries were recorded. The statistical analysis included the calculation of Kaplan-Meier survival curves, log-rank tests and a Cox proportional hazard regression model. No adverse events were documented. The proportion of completely intact sealants and those with minimal loss was almost identical in both groups, at 84.3% (Helioseal F; 113/134) and 81.7% (Helioseal F Plus; 107/131) after three years of observation. The regression analysis revealed an operator dependency, but no significant differences were found between the materials, the study centers, the chosen isolation technique, patient age or sex. After 3 years, 91.7% and 100.0% of all molars were free of non-cavitated carious lesions or carious cavities, respectively. It can be concluded that the new fissure sealing material can be considered as at least equivalent in terms of survival and retention behavior compared to the predecessor material.

Association Study on Nutrition in the First Year of Life and Molar-Incisor Hypomineralization (MIH)-Results from the GINIplus and LISA Birth Cohort Studies.

Molar-incisor hypomineralization (MIH) is a condition with specific clinical presentation whose etiology to date still remains unknown. This study prospectively investigated the association between nutrition during the 1st year of life and the presence of MIH in the permanent dentition. Data from 1070 10-year-old children from two prospective birth cohort studies were included. Information on exclusive breastfeeding (EBF) and introduction of 48 food items into the child's diet was assessed at 4-, 6-, and 12-month time-points. Food diversity was defined according to the number of food items or food groups introduced into the child's diet and then subsequent categorization into low-, middle- and high-diversity groups was performed. MIH was scored in the permanent dentition at age of 10 years. The statistical analysis included logistic and Poisson hurdle regression models adjusted for potential confounders. EBF, food item and food group diversity at 4-, 6-, 12-month time-points were found to be non-significant in most of the categories for the development of MIH. However, significantly higher odds for the presence of MIH were found for certain categories. Despite the limitation of this study, such as arbitrary cut-offs for categorization of food items, the results of this study suggest the lack of an association between early nutrition in the first year of life and MIH in the permanent dentition.

The effect of ethanol wet bonding technique on postoperative hypersensitivity of Class II composite restorations: A randomized trial.

BACKGROUND: To evaluate the effect of Ethanol Wet Bonding Technique (EWBT) on postoperative hypersensitivity (POH) of composite restorations in premolar teeth. MATERIALS AND METHODS: In this randomized trial, 24 patients with at least three proximal carious lesions with similar axial depth and position of gingival floor in their premolars were enrolled. Following cavity preparation, the teeth were randomly assigned to one of three groups: (1) Class II resin-based composite (RBC) restoration using an etch-and-rinse adhesive + wet bonding technique (Control); (2) RBC restoration using EWBT + hydrophobic adhesive; and (3) RBC restoration using EWBT + hydrophilic adhesive. Tooth hypersensitivity was evaluated before and 1, 3, 7, 14 and 30 days after treatment according to the Visual Analog Scale. Data were analyzed statistically with Kruskal-Wallis and Friedman tests (P = 0.05). RESULTS: All teeth showed similar levels of hypersensitivity after treatment (both P > 0.05). Furthermore, there was no difference between POH levels of the test and control groups at any control period (P < 0.05). Friedman test indicated that the POH significantly reduced within time in all groups (P < 0.05). CONCLUSION: Application of ethanol-wet bonding technique, either with hydrophobic or hydrophilic adhesives did not affect the POH of Class II composite restorations in premolars.

Hypersensitivity in teeth affected by molar-incisor hypomineralization (MIH).

Tooth hypersensitivity is a common symptom in patients with molar-incisor hypomineralization (MIH). Therefore, this clinical study aimed to assess potential associations between patient- and tooth-related variables and the intensity of hypersensitivity in MIH-affected permanent teeth compared to healthy controls. Fifty-seven MIH patients and 20 healthy adolescents with a total of 350 MIH-affected and 193 healthy teeth were included in this study. The intensity of hypersensitivity was measured after cold air stimulation using the Schiff Cold Air Sensitivity Scale (SCASS) by the dentist and visual analogue scale (VAS) by the patient. Tooth hypersensitivity was low in non-MIH teeth (97.9% of the group had zero SCASS and VAS values). In contrast, MIH-affected teeth with demarcated opacities and atypical restorations had moderate SCASS and VAS values, whereas teeth with enamel breakdown were mostly linked to severe hypersensitivity. The logistic regression model confirmed a significantly lower level of hypersensitivity in MIH patients aged ≥ 8 years (OR 0.06, 95% CI 0.01-0.50, p = 0.009) and higher levels in molar teeth (OR 5.49, 95% CI 1.42-21.27, p = 0.014) and teeth with enamel disintegration (OR 4.61, 95% CI 1.68-12.63, p = 0.003). These results indicate that MIH-related tooth hypersensitivity seems to be present in disintegrated molars immediately after tooth eruption.