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Showing 3 results for Accuracy
Variations among dentists in visual and radiographic diagnosis of occlusal caries
J. Pourhashemi, F. Mohandes, Ar. Talaeipour,
Volume 21, Issue 1 (10-2008)
Abstract

Background and Aim: Diagnosis of occlusal caries in early stages is more difficult than other types, and  needs practical proficiency and accuracy as well as application of advanced and modern equipments. The aim of this study was to evaluate the variations among dentists in diagnosis of occlusal caries.

Materials and Methods: In this descriptive cross-sectional study, 6 permanent first molar teeth of 8-10 years old children with occlusal caries of 1, 2 and 3 degrees were selected (Espelid method). Color photographs and bitewing radiographs of teeth were displayed on computer monitor and 157 general dentists were asked to determine the existence and depth of caries. Data were analyzed using SPSS software and chi-square test. P<0.05 was considered as the level of significance.

Results: 94% of dentists did not diagnose any lesion in grade I caries.3.8% reported enamel caries (correct diagnosis) and 1.9% reported dentin caries. In grade II caries, 15.7% of dentists could not diagnose any caries, 60.7% recognized the caries at the level of enamel (correct diagnosis), and 22.31% reported the dentin level, and 1.3% reported pulp exposures.7% of dentists could not diagnose any caries in grade III, while 27.2% recognized lesions at enamel and 58.9% at dentin level (correct diagnosis), 6.1% of dentists reported pulp exposures and 0.3% did not respond. Female dentists showed significantly higher correct diagnosis compared to males (p=0.013).

Conclusion: Based on the results of this study, despite considerable variations among general dentists in diagnosis of occlusal caries, the total accuracy was acceptable.


Accuracy of implant transfer with open-tray and closed-tray impression techniques and surface detail reproduction of the tooth during impression
Marziyeh Alikhasi, Abbas Monzavi, Hakimeh Siadat, Bita Fathi,
Volume 25, Issue 2 (4-2012)
Abstract

Background and Aims: Accurate recording of implant location is required to achieve passive fit and have the implants without stress concentration. The aim of this in-vitro study was to evaluate the dimensional and angular accuracy of open-tray and closed-tray impression techniques using polyether impression material and also to assess the surface detail reproduction of the tooth while impression making.

Materials and Methods: One reference metal model with 2 implants (Implantium) on the position of the maxillary second premolar and first molar and one molar tooth for evaluation of surface details was prepared. 27 polyether impressions of these models were made (9 using open-tray, 9 using closed-tray techniques and 9 were made just of the surface of the teeth without any implants). Impressions were poured with ADA type IV stone. Coordinate Measuring Machine was used for measuring the dimensional accuracy and video measuring machine for surface detail reproduction. All of these measurements were compared with the measurements on the reference model. Data were analyzed by and compared by T-test and One-way ANOVA.

Results: There was a significant statistical difference between open-tray and closed-tray techniques (P<0.001). There was no significant difference in the surface detail reproduction of open-tray and Closed-tray techniques and impression making with or without the implants (P>0.05).

Conclusion: The accuracy of open-tray impression technique was more than closed-tray technique. The surface detail reproduction of the tooth was not affected by impression technique.


Evaluation of the accuracy of Trios5 intraoral scanner in determining the color of ceramic samples
Elnaz Shafiee, Amin Nourizadeh, Parisa Jafarzadeh Maleki,
Volume 38, Issue 0 (4-2025)
Abstract
Background and Aims: Achieving reliable tools for accurate shade matching of ceramic samples is of great importance in restorative and aesthetic dentistry. This study aimed to evaluate the accuracy of the Trios5 intraoral scanner in determining the shade of ceramic samples using the Vita Classical Shade Guide (VC).
Materials and Methods: This in-vitro study involved scanning each ceramic sample 15 times by two independent observers using the Trios5 intraoral scanner. The detected shade of each sample was compared with the reference shades of the Vita Classical Shade Guide (VC) and the compatibility of the scanner’s results with the reference shades was assessed. The data were analyzed using SPSS24 software and Pearson correlation and paired t-tests and kappa coefficient at a significance level of 0.05.
Results: The highest accuracy of shade detection in both observers was found for shades A2, A3, A3.5, A4, B1, and C4, each with 100% accuracy. The lowest accuracy for both observers was noted for shade A1, with 0% accuracy. The mean overall accuracy for the first and second observers was 64.99% and 63.75%, respectively, with a total overall accuracy of 64.37%. A statistically significant interobserver agreement was observed (P≤0.005).for all shades except B2 (P=0.299).
Conclusion: The Trios5 intraoral scanner can be considered a useful adjunct tool for ceramic shade determination. However, for clinical applications, it is recommended to use it in conjunction with reference tools and complementary methods such as spectrophotometry or visual assessment by experienced clinicians.

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