Comparison of different digital shade selection methodologies in terms of accuracy

PURPOSE

This study aims to evaluate the accuracy of different shade selection techniques and determine the matching success of crown restorations fabricated using digital shade selection techniques.

MATERIALS AND METHODS

Teeth numbers 11 and 21 were prepared on a typodont model. For the #11 tooth, six different crowns were fabricated with randomly selected colors and set as the target crowns. The following four test groups were established: Group C, where the visual shade selection was performed using the Vita 3D Master Shade Guide and the group served as the control; Group Ph, where the shade selection was performed under the guidance of dental photography; Group S, where the shade selection was performed by measuring the target tooth color using a spectrophotometer; and Group I, where the shade selection was performed by scanning the test specimens and target crowns using an intraoral scanner. Based on the test groups, 24 crowns were fabricated using different shade selection techniques. The ΔE values were calculated according to the CIEDE2000 (2:1:1) formula. The collected data were analyzed by means of a one-way analysis of variance.

RESULTS

For the four test groups (Groups C, Ph, S, and I), the following mean ΔE values were obtained: 2.74, 3.62, 2.13, and 3.5, respectively. No significant differences were found among the test groups.

CONCLUSION

Although there was no statistically significant difference among the shade selection techniques, Group S had relatively lower ΔE values. Moreover, according to the test results, the spectrophotometer shade selection technique may provide more successful clinical results.

Comparison of color accuracy and picture quality of digital SLR, point and shoot and mobile cameras used for dental intraoral photography - A pilot study

The present study aimed to compare the picture quality and color accuracy of three cameras, namely, Point and shoot, DSLR and mobile cameras, and determine the most suitable camera for dental photography (intra-orally and for casts). A computer program, namely, NRM (No-Reference matrix BRISQUE), was used to evaluate the quality of the photos taken by three cameras. Further, color accuracy was determined by computation of total color difference (ΔE) by identifying the L∗a∗b∗ values.

The ANOVA (Kruskal-Wallis) analysis was done to assess the difference in the quality of cast photos, and it showed a statistically significant difference (p < 0.05) between the cameras. The post hoc analysis showed the NRM value of Point and shoot (18.93 ± 2.04) better than the Mobile phone (20.59 ± 2.65). However, no statistically significant difference was obtained while assessing the picture quality of the intraoral photographs using One-Way ANOVA (Fisher's) (P = 0.05).

Evaluation of total color difference (ΔE) showed fewer differences between the DSLR and the Point and shoot than the mobile camera. There was no statistically significant difference in ΔE value in the participant photographs. The L in the LAB values of both the cast and the participant photograph showed a similar result, with the mobile phone showing a lighter value than the other two cameras. The B value in the participant photos showed a significant difference between the mobile and the Point and shoot cameras.

The quality of Point and shoot, DSLR, and mobile cameras were equally good for taking pictures of any external surface, but the mobile camera offered more brightness and appeared more yellow. On the other hand, the quality was similar for intraoral images with mobile and Point and shoot cameras, although color accuracy was better with Point and shoot and DSLR cameras.

Prediction accuracy of Dolphin software for soft-tissue profile in Class I patients undergoing fixed orthodontic treatment

BACKGROUND

Simulation and prediction can facilitate the decision between an extraction versus nonextraction treatment plan. This study aimed to assess the accuracy of Dolphin Imaging software in predicting profile changes in class I borderline cases.

METHODS

In this retrospective study, class I borderline patients (i.e., both extraction and nonextraction treatment plans were possible for them) aged 15-35 years were enrolled. All of the cephalometric analyses were done by Dolphin Imaging software, version 11.8 Premium. The initial cephalograms were superimposed on initial photographs. The final values for the 7 angular and linear landmarks of the upper and lower incisors were extracted from post-treatment cephalograms and inserted in the "Goals" tab of the Dolphin Imaging software. Post-treatment images of patients were simulated. Final post-treatment photographs were superimposed on the simulated pictures. The differences between the real and simulated pictures were calculated in relation to the reference lines. The P value was set at 0.05.

RESULTS

A total of 70 patients (36 with tooth extraction, and 34 without tooth extraction) were included. In the extraction group, the horizontal position of both lips was predicted to be significantly more protruded than it actually was, whereas in the nonextraction group, the only difference between the simulated and actual results was that the vertical position of the lower lip, which was simulated as being more inferior than it actually was.

CONCLUSIONS

Despite the statistically significant differences between the real and simulated pictures, the differences were small and clinically insignificant. Prediction via Dolphin Imaging software can be an appropriate guide in extraction-nonextraction borderline cases.

Computerized delineation of the teeth and comparison with a smiling photograph: identification of a body skeletonized by cadaverous ichthyofauna action

Amazonian's forensic experts usually experience considerable difficulties in the identification of drowned bodies rescued from the rivers of the Amazon basin, since they are frequently found skeletonized by the action of the cadaverous ichthyofauna. In these circumstances, especially when the soft tissues are completely absent, bones and teeth may represent the unique source of information for the identification of the body. This work reports a case of positive identification of a body skeletonized by scavenger ichthyofauna. The identification was performed by comparing computerized delineation of the dental characteristics of the cadaver with those observed in a smiling photograph of the victim. This report also highlights the ferocity of Cetopsis candiru (candiru cobra), Cetopsis coecutiens (candiru-açu) and Calophysus macropterus (piracatinga).

A Beginning Guide for Dental Photography: A Simplified Introduction for Esthetic Dentistry

Photography is one of the most important skills dentists need to master in order to perform esthetic dentistry at a high level. Today, digital single-lens reflex cameras are commonplace. Young dentists have grown up with Internet, smartphones, and online platforms exposing them, and their patients, to cases that other dentists have shared, increasing the awareness and popularity of esthetic-focused treatment. This article provides readers with a simplified and attainable approach to begin the dental photography journey, as well as increase skill level, depending on practice style and desired investment.

A cross-sectional survey to evaluate acquaintance about dental photography among dental students in daily clinical practice

Background: In today's world of digital dentistry, dental photography plays an important role as multilevel significance and represents the synonym of contemporary dentistry. Thus, we aimed at evaluating the acquaintance of practice, opportunity and morals of dental photography in everyday practice among undergraduate dental students. Design and Methods: The current research was an observational cross-sectional study. Total 233 students participated; each was given questionnaire consisted of three parts covering the following aspects: questions 1 to 3 on the practice of dental photography, questions 4 to 7 on morals in dental photography and question 8 to 11 on opportunities of dental photography. The answers were tabulated and statistically analysed and association with the factors were tested for significance using Chi-square tests, and P<0.05 was considered statistically significant. Results: The total response rate was 86%. Among the 201 respondents, 100 were males and 101 females; 96% male students were taking photographs and 93% females were taking photographs, on regular basis. Phone cameras (41.3%) were the most commonly used device followed by DSLR cameras. Surveyed students mentioned patient education (53.2%) as most needed requirement for taking photographs, followed by treatment planning (49.8%) and monitoring of the treatment outcome (34.3%). Ninety-one percent of students feel that there is an opportunity for advancement in dental photography techniques. Conclusions: The participants aware of dental photography, but they require detail insight on proper capturing of photographs and morals, with regards to confidentiality of the patient and patient consent.

Photogrammetry as an alternative for acquiring digital dental models: A proof of concept

Photogrammetry is a mathematical technique that generates three-dimensional coordinates of specific points identified from multiple images of the same object obtained at different angles. This technique may be a low-cost alternative for traditional scanning. The objective of this proof of concept was to evaluate the accuracy and precision in obtaining digital models (DM) from a plaster model (PM) using photogrammetry. Five DM were generated from 50 photographs taken surrounding the PM. The photographs were taken by a single operator on five consecutive days using natural light. The images obtained were processed on 3DF Zephyr Free software. The height and width of all teeth were recorded on both PM and DM, as well as the distance between the canine cusps (C-C) and between the mesiobuccal cusps of the first molars (1 M-1 M). For the PM the measurements were taken with a digital caliper, whereas the DM was measured using the software Blender. The DM and PM measurements presented a limit of agreement between -0.433 and 0.611 mm. The accuracy of DM measurements showed a SD of ±0.171 mm and a repeatability coefficient of 0.474. In the superimposition of all DM, it was possible to notice a greater discrepancy in the posterior region of the arch and palate, but this difference decreased when the region was segmented. It can be concluded that photogrammetry appears to be a viable technique for the digitization of dental models. Further studies need to be performed to evaluate its clinical application.

Instructional design of a clinical photography course for undergraduate dental students

Clinical and dental photography is an acquired skill. It is learned, developed and practised at post-graduate level by medical photographers across the U.K. But where does the medical photography profession stand in terms of transmitting slowly acquired skills to a wider clinical audience? If some or all skills need to be passed on, how and to whom should they be taught? This paper considers how dental practitioners may benefit from training in specific aspects of clinical photography and suggests a tried and tested model of instructional design for a clinical photography course utilised and implemented for undergraduate dental students studying at the University of Leeds. The authors found a course of this nature demanded skills and theoretical understanding of cognitive architecture beyond the purview of most clinical field experts. A collaborative approach to instructional design between a field expert and clinical educator was implemented, which allowed the design of a dental photography course that worked effectively by linking new to prior knowledge.

Digital dental photography

Photography has always been an integral part of dentistry. The journey goes back to the time when film photography was used only for documentation and referral purpose which has now evolved to digital photography. Its application in dental practice is simple, fast, and extremely useful in documenting procedures of work, education of patients, and pursuing clinical investigations, thus providing many benefits to the dentists and patients. The article describes the added benefits of digital dental photography over film photography, basic armamentarium for obtaining good photographs, and how digital dental photography is beneficial in the field of prosthodontics.

Comparison of red autofluorescing plaque and disclosed plaque-a cross-sectional study

Objectives

The aim of this cross-sectional study was to assess the correlation between dental plaque scores determined by the measurement of red autofluorescence or by visualization with a two-tone solution. Clinical photographs were used for this study.

Materials and methods

Overnight plaque from the anterior teeth of 48 participants was assessed for red fluorescence on photographs (taken with a QLF-camera) using a modified Quigley & Hein (mQH) index. A two-tone disclosing solution was applied. Total disclosed plaque was clinically assessed using the mQH index. In addition, total and blue disclosed plaque was scored on clinical photographs using the mQH index.

Results

A strong correlation was observed between the total disclosed plaque scored on photographs and the clinical scores (r = 0.70 at site level; r = 0.88 at subject level). The correlation between red fluorescent plaque and total plaque, as assessed on the photographs, was moderate to strong and significant (r = 0.50 at the site level; r = 0.70 at the subject level), with the total plaque scores consistently higher than the red fluorescent plaque scores. The correlation between red fluorescent plaque and blue disclosed plaque was weak to moderate and significant (r = 0.30 at the site level; r = 0.50 at the subject level).

Conclusions

Plaque, as scored on white-light photographs, corresponds well with clinically assessed plaque. A weak to moderate correlation between red fluorescing plaque and total disclosed plaque or blue disclosed plaque was found.

Clinical relevance

What at present is considered to be matured dental plaque, which appears blue following the application of a two-tone disclosing solution, is not in agreement with red fluorescent dental plaque assessment.

Evaluation of a photographic method to measure dental angulation

Objective

To analyze the reliability and reproducibility of a simplified method for analysis of dental angulation using digital photos of plaster dental casts.

Methods

Digital and standardized photographs of plaster casts were performed and posteriorly imported to an angle reading graphic program in order to have measurements obtained. Such procedures were repeated to evaluate the random error and to analyze reproducibility through intraclass correlation. The sample consisted of 12 individuals (six male and six female) with full permanent dentition orthodontically untreated. The analyses were bilaterally carried out, and generated 24 measurements.

Results

The random error showed variation of 0.77 to 2.55 degrees for teeth angulation. The statistical analysis revealed that the method presents excellent reproducibility (p < 0.0001) for all teeth, except for the upper premolars. In spite of that, it is still considered statistically significant (p < 0.001).

Conclusion

The proposed method presents enough reliability that justifies its use in the development of scientific research as well as in clinical practice.