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Effect of high-fluoride dentifrice and bracket bonding composite material on enamel demineralization in situ

Original Article

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Abstract

Objective

This in situ study evaluated the effect of high-fluoride dentifrice (5000 μg F/g) and fluoride-containing bonding composite resin on enamel demineralization adjacent to orthodontic brackets.

Methods

Ten volunteers wore palatal appliances containing bovine enamel blocks with metallic brackets bonded with fluoride-free or fluoride-containing composite resin. During three phases of 14 days each, three dentifrices with different fluoride concentrations (0, 1100, and 5000 μg F/g) were tested. The cariogenic challenge consisted of 20% sucrose solution dripped 8x/day onto the dental blocks. At the end of each phase, biofilm formed was collected for fluoride analysis. Cross section hardness was performed in enamel blocks, and the lesion area was calculated. Data were analyzed by two-way ANOVA followed by Tukey post hoc test (α = 5%).

Results

The only signicant factor for all the variables under study was the dentifrice. Smaller lesion area and higher fluoride concentration on biofilm were found in 5000 μg F/g group, irrespective of bonding composite resin (p < 0.001). Neither bracket-bonding composite resin nor the interaction between the factors was statistically significant (p > 0.05) for all the variables.

Conclusion

High-fluoride dentifrice is effective in reducing demineralization on enamel adjacent to orthodontic brackets, while the fluoride-containing bonding composite resin does not influence it.

Clinical Significance

Since high-fluoride dentifrice was able to reduce demineralization adjacent to brackets, it can be an option to caries management in orthodontics patients.
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Dental caries diagnosis in digital radiographs using back-propagation neural network

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Abstract

Purpose

An algorithm for diagnostic system with neural network is developed for diagnosis of dental caries in digital radiographs. The diagnostic performance of the designed system is evaluated.

Methods

The diagnostic system comprises of Laplacian filtering, window based adaptive threshold, morphological operations, statistical feature extraction and back-propagation neural network. The back propagation neural network used to classify a tooth surface as normal or having dental caries. The 105 images derived from intra-oral digital radiography, are used to train an artificial neural network with 10-fold cross validation. The caries in these dental radiographs are annotated by a dentist. The performance of the diagnostic algorithm is evaluated and compared with baseline methods.

Results

The system gives an accuracy of 97.1%, false positive (FP) rate of 2.8%, receiver operating characteristic (ROC) area of 0.987 and precision recall curve (PRC) area of 0.987 with learning rate of 0.4, momentum of 0.2 and 500 iterations with single hidden layer with 9 nodes.

Conclusions

This study suggests that dental caries can be predicted more accurately with back-propagation neural network. There is a need for improving the system for classification of caries depth. More improved algorithms and high quantity and high quality datasets may give still better tooth decay detection in clinical dental practice.
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Evaluation of the Precision of Different Intraoral Scanner-Computer Aided Design (CAD) Software Combinations in Digital Dentistry.

Med Sci Monit. 2020 Jan 3;26:e918529. doi: 10.12659/MSM.918529.

Abstract

BACKGROUND The aim of this study was to evaluate the precision of correlation between intraoral scanners and computer aided design (CAD) software programs used during scanning and designing phases of digital dentistry. In the present study, CAD software programs that accept data in Standard Tessellation Language (STL) and proprietary format have been evaluated and data loss has been examined in the scanned data.

MATERIAL AND METHODS A single unit crown preparation was conducted for maxillary right first molar on a fully dentulous model. The prepared tooth was scanned with a high precision industrial scanner (ATOS Core 80) and the reference digital model was obtained. The dental model was further scanned 10 times using 3 different intraoral scanners (CEREC Omnicam AC, TRIOS 3 Color Pod, and Aadva IOS 100). The data obtained from the reference scanner and intraoral scanners were transferred to different CAD programs (CEREC inLab, TRIOS Design Studio, Exocad) and digital crowns were designed for each scanned data-CAD combination. After that, the data losses that occurred between these transfers were evaluated by superimposition technique in a special software (VR Mesh v7.5) (alpha=0.05).

RESULTS Among the all combinations of scanner and software, Omnicam AC-InLab was determined to be the most precise combination through the full digital workflow since the Omnicam AC-Exocad combination showed the highest deviations.

CONCLUSIONS Within the limitations of this in vitro study, it was determined that the combinations of scanners and associated CAD programs yielded more accurate results, and data loss was revealed when the scanned data converted from the proprietary format to the STL format.

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Single application of 0.8% hyaluronic acid as a coadjuvant of nonsurgical treatment in nonsmoking patients with periodontitis: A split-mouth, randomized, controlled pilot clinical trial

Lobato JC, Santos Vilhena MA, Izidoro C, Alves RC, Proença L. Single application of 0.8% hyaluronic acid as a coadjuvant of nonsurgical treatment in nonsmoking patients with periodontitis: A split-mouth, randomized, controlled pilot clinical trial. J Indian Soc Periodontol 2019;23:545-8

Background: Topical coadjuvants might be indicated to increase the results of nonsurgical periodontal treatment and overcome some of its limitations. The aim of this study was to evaluate the clinical benefits of a single topical application of 0.8% hyaluronic acid (HA) as a coadjuvant to scaling and root planing (SRP) in periodontal patients.

Materials and Methods: Sixteen patients diagnosed with periodontitis were recruited to participate in this split-mouth randomized controlled trial. At baseline, oral hygiene instructions, prophylaxis, and SRP were performed in both sides; additionally, a subgingival application of HA at 0.8% was made in the test side. Several clinical parameters were assessed at baseline, 6, and 12 weeks later: full mouth plaque score, gingival score, bleeding on probing (BoP), probing depth (PD), and clinical attachment level (CAL).  

Results: At the end of 12 weeks, there was a overall improvement in all periodontal parameters in both sides (P < 0.05). Test sides showed less BoP when compared to the control sides (9.4 ± 4.0 vs. 14.9 ± 8.9, P < 0.05). Other periodontal parameters such as PD and CAL showed a slight improvement in comparison with the control sides, but the difference was not statistically significant (P > 0.05).  

Conclusion: Results from this study indicate that a single subgingival application of 0.8% HA seems to reduce gingival inflammation and improve clinical parameters, particularly BoP. Further studies are needed to evaluate the effect of repeated application of HA and long-term results.

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Full digital workflow for crown lengthening by using a single surgical guide

The Journal of Prosthetic Dentistry

Available online 29 November 2019

The Journal of Prosthetic Dentistry

Abstract

A technique using a digital workflow for performing crown lengthening by using a free software program is presented to digitally design a single surgical guide. The technique consists of obtaining standard tessellation language (STL) files from intraoral scans from a digital design of the new tooth shape and from a cone beam computed tomography (CBCT) scan, after which Digital Imaging and Communications in Medicine (DICOM) files are converted to the STL format. These files are then superimposed and used for surgical planning of the crown-lengthening procedure. The main component of the surgical guide is a labial upper band representing the biological width measurement based on the predicted digitally designed future gingival margin position. Accordingly, the lower edge of the band indicates the level of the main marginal incision, whereas the top of the band indicates the level where the alveolar bone crest must be repositioned by alveolotomy during the surgical crown-lengthening procedure. By performing an adequate diagnosis of the potential restorative outcome, the new position of the gingival margin and the crown shape can be predicted, and whether osteoplasty is needed can be determined.
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The Recommendation of Cone-beam Computed Tomography and Its Effect on Endodontic Diagnosis and Treatment Planning

Published online: December 16, 2019

Abstract

Introduction

Although intraoral radiographs are foundational for diagnosis and planning treatment in dentistry, the resulting 2-dimensional image varies in interpretation requiring judgment. Cone-beam computed tomographic imaging provides a more detailed 3-dimensional image that may affect treatment recommendations. This study aimed to determine the basis for CBCT recommendations and the effect on diagnosis and treatment planning.

Methods

The study involved a sample of 45 cases that presented for endodontic treatment, 30 with a CBCT scan on record and 15 without. For phase 1, all 45 cases were reviewed by 3 examiners without access to the CBCT scans. For phase 2, 4 months later, the 3 examiners reanalyzed the 30 cases, this time with the associated CBCT scan. Intra- and interexaminer agreements were recorded and analyzed. Also, the recommendations for CBCT were compared with the American Association of Endodontists/American Academy of Oral and Maxillofacial Radiology joint statement.

Results

Interexaminer agreement in phases 1 and 2 was 65% and 72%, respectively. For endodontic diagnoses, there was a 19% change in the pulpal diagnosis category when CBCT imaging was added, whereas there was a 30% change in the apical category. The selections changed in 55% of the cases when determining etiology and in 49% of the cases when making recommendations. CBCT imaging was recommended 78.8% of the time when the case had a CBCT on record versus 33% of the time in cases without.

Conclusions

CBCT imaging has a significant effect in determining the etiology of endodontic pathoses and in recommending treatment. Furthermore, CBCT imaging is not overprescribed in the endodontic department, and the faculty members adhere to the American Association of Endodontists/American Academy of Oral and Maxillofacial Radiology recommendations.

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