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1.
Saudi Dent J ; 36(7): 1043-1050, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39035566

RESUMO

Purpose/Objectives: This article introduces the Key Electronic Assessment Platform (KEAP), an electronic-based assessment platform created in-house at the College of Dentistry (COD), King Saud bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia. It highlights the platform's integral value and demand within the educational system. Methods: The article introduces the KEAP system design and architecture, describes its features, tests, and implementation in addition to its maintenance and security. It also presents the outcomes of KEAP utilization and the level of users' satisfaction. Results: The KEAP item bank has been expanded by more than 26,500 questions over the last four academic years and 1,255 exams have been administered. KEAP provides a highly secure structured framework for assessment planning, conduction, and evaluation. More than 90% of students and faculty are satisfied or very satisfied with their experience using the KEAP system indicating that it is well accepted by the end users. Conclusions: The development of KEAP is based on contextual factors in COD, KSAU-HS with the aim of creating a process for assessment that is valid, efficient, standardized, and highly secure. KEAP's design and successful implementation can provide a successful example of implementing electronic-based assessment in higher education.

2.
Clin Oral Investig ; 27(12): 7489-7499, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37971540

RESUMO

OBJECTIVES: The aim was to compare the porosity of different bulk-fill resin-based composites (RBCs) placement techniques to the conventional incremental technique using microcomputed tomography (µ-CT). MATERIAL AND METHODS: Occlusal cavities were prepared on extracted human molars, divided into five groups based on the placement technique (n = 10/group). Techniques examined were Monoblock-two-step (SureFil SDR flow + Ceram.X), Monoblock-two-step (Tetric EvoFlow Bulk-Fill + Tetric EvoCeram Bulk-Fill), Monoblock-one-step (Tetric EvoCeram Bulk-Fill), Monoblock with sonic activation (SonicFill2), and incremental technique (Filtek Z250). µ-CT scanning (SkyScan, Bruker, Belgium) assessed the number, volume of closed pores, and total porosity. Analysis of variance on ranks was used (Student-Newman-Keuls method and Mann-Whitney rank-sum test), to determine the significance of RBC viscosity and the sonication placement technique. The Spearman correlation method assessed the correlation between porosity characteristics (α = 0.05). RESULTS: The SonicFill2 presented a higher number of closed pores than the other groups (p < 0.05). The overall porosity within the restoration seemed greater in this order: Filtek Z250 > SonicFill2 > Tetric EvoFlow Bulk-Fill + Tetric EvoCeram Bulk-Fill > Tetric EvoCeram Bulk-Fill > SureFil SDR Flow + Ceram.X. Sonication was associated with increased number (p = 0.005) and volume (p = 0.036) of closed pores. A strong correlation was observed between the number and volume of closed pores (R2 = 0.549, p < 001). CONCLUSIONS: The monoblock technique with sonic activation showed significantly more internal porosity than the other placement techniques. Sonication during application contributed to the higher number and volume of closed pores than the passive bulk-fill application. CLINICAL RELEVANCE: Using bulk-fill materials enhances efficiency, yet void formation remains an issue, depending on viscosity and active/passive delivery of materials. Clinicians must familiarize themselves with effective placement techniques to reduce void formation and optimizing treatment outcomes.


Assuntos
Resinas Compostas , Materiais Dentários , Humanos , Microtomografia por Raio-X , Porosidade , Teste de Materiais , Viscosidade , Restauração Dentária Permanente/métodos
3.
Tomography ; 9(4): 1369-1380, 2023 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-37489477

RESUMO

This study's aim is to determine the accuracy and precision of the bracket slot height in MBT 0.022″ ceramic brackets. Five brackets from 11 different systems (n = 55) were scanned using micro-computed tomography (micro-CT). The slot height was measured at the face (external) and base (internal) of the slot. Data were analyzed using a One-Sample t-Test, and a Paired t-Test. The lowest external height was seen in OrthoCare Purity® at 0.02264″ (2.9%), and the greatest in TOC Ghost Advanced® at 0.02736″ (24.4%). The lowest internal height was seen in Forestadent Glam® at 0.02020″ (-8.2%), and the greatest in TOC Ghost Advanced® at 0.2547″ (15.8%). OrthoCare Purity® measurements corresponded most closely with the expected measurements. TP InVu® was found to be the most precise bracket for external height (range = 0.00043″) and American Orthodontics 20/40® for internal height (range = 0.00028″). In assessing slot geometry, all brackets demonstrated a higher mean external slot height compared to the internal measurements at the base of the bracket. Orthodontic bracket slots are larger than expected and slot parallelism was not observed in any bracket brand tested. Similarly, slot dimensions are imprecise where two 'identical' brackets have different slot sizes. The clinician should, therefore, assume that play is most likely higher than expected.


Assuntos
Desenho de Aparelho Ortodôntico , Braquetes Ortodônticos , Microtomografia por Raio-X , Cerâmica
4.
Biomedicines ; 11(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37371706

RESUMO

Oral cancer (OC) is one of the most common forms of head and neck cancer and continues to have the lowest survival rates worldwide, even with advancements in research and therapy. The prognosis of OC has not significantly improved in recent years, presenting a persistent challenge in the biomedical field. In the field of oncology, artificial intelligence (AI) has seen rapid development, with notable successes being reported in recent times. This systematic review aimed to critically appraise the available evidence regarding the utilization of AI in the diagnosis, classification, and prediction of oral cancer (OC) using histopathological images. An electronic search of several databases, including PubMed, Scopus, Embase, the Cochrane Library, Web of Science, Google Scholar, and the Saudi Digital Library, was conducted for articles published between January 2000 and January 2023. Nineteen articles that met the inclusion criteria were then subjected to critical analysis utilizing QUADAS-2, and the certainty of the evidence was assessed using the GRADE approach. AI models have been widely applied in diagnosing oral cancer, differentiating normal and malignant regions, predicting the survival of OC patients, and grading OC. The AI models used in these studies displayed an accuracy in a range from 89.47% to 100%, sensitivity from 97.76% to 99.26%, and specificity ranging from 92% to 99.42%. The models' abilities to diagnose, classify, and predict the occurrence of OC outperform existing clinical approaches. This demonstrates the potential for AI to deliver a superior level of precision and accuracy, helping pathologists significantly improve their diagnostic outcomes and reduce the probability of errors. Considering these advantages, regulatory bodies and policymakers should expedite the process of approval and marketing of these products for application in clinical scenarios.

5.
Sci Rep ; 13(1): 9357, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37291272

RESUMO

This study investigated retreatment of oval canals filled with gutta-percha and different sealers using WaveOne Gold (WOG). Single oval canals were prepared to size 30, 0.04 and obturated with gutta percha and AH Plus (AHP) or TotalFill bioceramic (TFBC) sealer. After 6-month incubation, the canals were retreated with WOG Primary (25, 0.07) under simulated body temperature, and the developed load and torque were simultaneously measured. The time and regaining the apical patency were checked. Micro-computed tomography scanning was performed to calculate the remaining obturating materials. An independent t-test and chi-square test were performed at a 95% confidence level. A shorter retreatment time was needed in TFBC than in AHP (P = 0.003). However, a higher maximum apical load was reported with AHP (P = 0.000). Meanwhile, comparable maximum coronal load and maximum torque values were observed. Apical patency was regained in all TFBC roots and only 75% of the AHP samples (P = 0.217). The remaining obturating materials were comparable in TFBC (13.02 ± 8.12%) and AHP (10.11 ± 8.46%) (P = 0.398). WOG was able to remove 89.89% and 86.98% of obturating materials in TFBC and AHP, respectively. The TFBC presented lower apical loads and faster retreatment compared to AHP.


Assuntos
Cavidade Pulpar , Obturação do Canal Radicular , Microtomografia por Raio-X , Obturação do Canal Radicular/métodos , Preparo de Canal Radicular/métodos , Guta-Percha , Retratamento
6.
Saudi Dent J ; 34(3): 243-248, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35935721

RESUMO

This study explores the effects of aging (thermal cycling and cyclic loading-TC/CL) and different light-curing unit (LCU) types on the volume characteristics and internal porosity of a bulk-fill resin-based composite restoration. Occlusal cavities (4 × 4 × 3 mm) were prepared on extracted human molars (n = 5). Tetric N-Bond Universal was applied, and the cavities were restored using Tetric-N-Ceram Bulk Fill. Photoactivation was performed using a quartz-tungsten halogen (QTH) or a multiple-emission peak light-emitting diode (MLED). Digital images for all restorations were obtained using microcomputed tomography (micro-CT) before (baseline) and after (post-aging) TC/CL (5,000 TC cycles in 5-55 °C baths and a dwell time of 30 s followed by 10,000 sinusoidal CL load cycles in an Instron B3000 at 2 Hz and 10-110 N) and storage (37 °C) for three months. For the micro-CT analysis, three-dimensional images were used to determine the restoration volume and internal porosity. Data were analyzed using a two-way ANOVA and Tukey's test (p < 0.05). Restorations photoactivated with QTH exhibited a higher object volume than the LED group at baseline and in post-aging conditions without any significant differences in the other evaluated characteristics. All volume/porosity characteristics increased considerably after TC/CL aging, except for the object volume of the QTH group and the closed porosity of the MLED group. The change in all the volume/porosity characteristics between both LCU groups after TC/CL were not significantly different. Thus, the aging process simulated herein increased the volume and porosity characteristics of the bulk-fill restoration, and no significant differences were obtained between the QTH and MLED equipment.

7.
Materials (Basel) ; 15(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35591647

RESUMO

This study assesses the retreatability of TotalFill bioceramic (TFBC) and AH Plus (AHP) sealers and their impact on retreatment force and torque. Twenty-six premolar teeth with single oval canals were instrumented, obturated using the matched gutta-percha cone technique with one of the tested sealers, and then temporized. After a 6-month incubation at 37 °C and 100% humidity, the canals were retreated with the XP Shaper system. During retreatment, the generated force and torque were measured. Micro-CT scanning was run before and after the retreatment procedure to analyze the remaining obturating materials in the canals. The apically directed maximum force in AHP was higher than that in TFBC. The coronally directed maximum force and the maximum torque were comparable between the groups. A higher amount of remaining obturating materials was found in the AHP compared to that in the TFBC. Based on these findings, endodontic sealer had an influence on retreatability, and the TFBC showed less remaining obturating materials and lower retreatment forces in the apical direction compared to the AHP in extracted teeth with oval canals.

8.
J Prosthodont ; 31(3): 252-256, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34021671

RESUMO

PURPOSE: To investigate, in vitro, the magnitudes of vertical load and torque generated during post space preparation of root canal treated teeth and their influence on microcrack development. MATERIALS AND METHODS: Forty extracted premolars with single canals were decoronated. The roots were prepared using ProTaper Next system (Dentsply Sirona) to X3 file, obturated, and provisionalized. After a 3-week incubation period, the roots were distributed into 2 groups according to the post drill system used (ParaPost fiber post and RelyX fiber post). During post space preparation, the vertical load, torque, and preparation time were recorded. Before and after the post space preparation, the roots were imaged with micro-computed tomography (SkyScan 1172; Bruker micro-CT) to detect new microcracks. The data were analyzed using the Mann-Whitney U-test and chi-square test. RESULTS: In ParaPost and RelyX, the post space was prepared in 48.31 ±25.28 and 47.71 ±13.36 seconds, respectively (p = 0.360). The peak vertical load generated with ParaPost (20.23 ±7.80 N) was significantly lower than that of RelyX (29.43 ±5.82 N) (p = 0.010). The maximum torque attained with ParaPost (1.42 ±0.61 N.cm) was found to be significantly lower than that of RelyX (3.23 ±1.58 N.cm) (p = 0.000). No post drill fracture or visible deformation was noticed throughout the experiment. New microcracks were found in three ParaPost samples only. CONCLUSIONS: The choice of postdrill influenced the loads and torques generated during postspace preparation. The ParaPost system showed favorably lower load and torque values during the postspace preparation compared with the RelyX system.


Assuntos
Cavidade Pulpar , Preparo de Canal Radicular , Dente Pré-Molar , Preparo de Canal Radicular/métodos , Torque , Microtomografia por Raio-X
9.
Dent Mater ; 35(10): 1464-1470, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31395451

RESUMO

OBJECTIVES: Enamel thickness determination by Cross-Polarization Optical Coherence Tomography (CP-OCT) is a promising approach for quantitative monitoring of tooth wear progression. This study evaluated the ability of CP-OCT to quantify the thickness of natural enamel before, during and after tooth wear simulation. MATERIALS AND METHODS: Natural, unpolished human dental enamel slabs were submitted to five wear stages (Wear 1: to level the surfaces; Wear 2 to Wear 5: 0.05±0.02mm reduction each) simulated by an automatic grinding/polishing machine. Enamel thickness was evaluated with CP-OCT and a gold-standard method (micro-CT) at baseline and after every wear stage. Data were analyzed using ANOVA with pairwise comparisons for wear stages' impact on the thickness and wear depth measurements. The inter-method agreement was analyzed using intra-class correlation coefficients, the difference between means, and Bland-Altman plots. RESULTS: Enamel thickness measurements (mean±standard error, in mm) with natural (1.40±0.05) and worn surfaces (1.08±0.02) by CP-OCT did not differ significantly from those measured by micro-CT (natural=1.39±0.05; worn=1.09±0.02; p-values=0.30 and 0.39, respectively). CP-OCT and micro-CT showed excellent agreement on natural (ICC=0.98) and worn surfaces (ICC=0.98) enamel thickness measurements. Among and between wear stages, there were significant differences in enamel thickness and wear depth measurements for both methods (p-value <0.0001 for all). Both methods yielded similar measurements' mean (0.14±0.01; p-value=0.87) and were in good agreement (ICC=0.77) for wear depth estimation. SIGNIFICANCE: CP-OCT allows accurate measurement of enamel thickness on natural tooth surfaces. Enamel thickness measurement by CP-OCT allows quantitative monitoring of enamel thickness changes and wear depth following progressive wear.


Assuntos
Desgaste dos Dentes , Dente , Esmalte Dentário , Humanos , Tomografia de Coerência Óptica , Microtomografia por Raio-X
10.
J Dent ; 81: 52-58, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30582963

RESUMO

OBJECTIVES: Optical Coherence tomography (OCT) is a promising clinical imaging technology for quantitative and objective assessment of dental erosion. We aimed to determine the influence of enamel surface roughness and demineralization severity (by erosive challenge) on dental surface loss measurements by cross-polarization OCT (CP-OCT). MATERIALS AND METHODS: Human enamel specimens were prepared with three surface roughness levels (very rough, rough and polished; n = 10 each). They were evaluated using CP-OCT and optical profilometry (gold standard) at baseline, and after 1, 2, 4, 6, 8, 16 and 24 h of erosion demineralization. The effects of roughness and demineralization on enamel loss were analyzed using ANOVA (alpha = 0.05). Intraclass correlation coefficients (ICCs) and Bland-Altman plots were used to evaluate inter-method agreement and intra-examiner repeatability. RESULTS: CP-OCT surface loss measurements did not significantly differ with the changes in enamel surface roughness (p = 0.27). Among demineralization severities, CP-OCT surface loss measurements at 1, 2, 4 and 8 h did not differ among each other, but they showed significantly lower enamel loss than 16 and 24 h; 6 and 16 h were significantly lower than 24 h (p < 0.05). Overall, CP-OCT and optical profilometry measurements did not differ (p = 0.73); however, ICC was relatively low (ICC = 0.34). Enamel loss estimation by CP-OCT presented an error of approximately ± 150 µm compared to profilometry. Intra-examiner repeatability with CP-OCT was excellent (ICC = 0.98). CONCLUSIONS: Enamel roughness did not affect CP-OCT measurements. The estimated error of CP-OCT measurements limited the appropriate assessment of enamel erosion surface loss, in the magnitude simulated in this study. CLINICAL RELEVANCE: Enamel thickness measurement by CP-OCT presents potential as an objective method for monitoring dental erosion lesions; however, its use may be limited for the assessment of the initial stages of enamel surface loss by erosion.


Assuntos
Desmineralização do Dente , Erosão Dentária , Esmalte Dentário , Humanos , Tomografia de Coerência Óptica
11.
J Dent ; 43(12): 1476-82, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26476416

RESUMO

OBJECTIVES: The aim of this study was to investigate the effect of erosion on direct tooth-coloured restorations and adjacent enamel/dentine under low and normal simulated salivary flow rates. METHODS: Bovine enamel and dentine specimens were prepared (n=16) and restored with the following materials: resin composite (FiltekZ250), resin-modified glass ionomer cement (Fuji II LC), high-viscosity glass ionomer cement (Fuji IX), and conventional glass ionomer cement (Fuji II). They were submitted to in vitro erosion-remineralisation cycling simulating normal (0.5 ml/min) and low (0.05 ml/min) salivary flow rates, for 5 days. The restorative material, enamel and dentine substrates were assessed with optical profilometry for surface loss. Mixed-model ANOVAs were used for statistical comparisons (alpha=0.05). RESULTS: Low-salivary flow significantly increased surface loss for all tested substrates (p<0.05), except FiltekZ250. Surface loss (mean±SD, in micrometres) under low-salivary flow was significantly higher in enamel (19.75±4.27) and dentine (23.08±3.48) adjacent to FiltekZ250 compared to Fuji II LC (16.33±2.30 and 20.47±2.58, respectively) and Fuji IX (15.79±2.41 and 20.63±2.34, respectively). Restoration surface degradation was significantly lower for Fuji II LC (2.17±0.73) than for both Fuji II (13.03±6.79), and Fuji IX (16.74±7.72) under low-salivary flow condition; whereas FiltekZ250 exhibited no meaningful surface loss (-0.35±0.19). CONCLUSION: Limited to these in vitro conditions, low-salivary flow promoted higher erosive conditions for teeth and restorations. Some fluoride-containing restorative materials may reduce erosive wear on adjacent enamel and dentine. FiltekZ250 resisted erosive surface loss. Fuji II LC showed both reduced acid degradation and protection of adjacent dental surfaces to erosion. CLINICAL SIGNIFICANCE: Patients at risk for erosion and in need of restorations may benefit from fluoride-containing restorative materials that resist erosive degradation. The data of this study suggest that resin-modified glass ionomer may be a suitable restoration for patients at higher risk of erosion with low exposure to fluoride.


Assuntos
Esmalte Dentário/metabolismo , Materiais Dentários/metabolismo , Restauração Dentária Permanente/métodos , Erosão Dentária/metabolismo , Resinas Acrílicas/química , Animais , Bovinos , Ácido Cítrico/química , Resinas Compostas/química , Esmalte Dentário/patologia , Materiais Dentários/química , Dentina/química , Dentina/patologia , Fluoretos/uso terapêutico , Cimentos de Ionômeros de Vidro/química , Incisivo , Dióxido de Silício/química , Xerostomia/patologia
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