Influence of individual education and training on quality of color matching in dentistry

Objectives: To evaluate the influence of the group and individual education of students on shade matching quality. Secondary study objective included a survey-assessment of quality and difficulty level of color matching.

Materials and methods: Forty dental student participants in Integrated Academic Studies of Dentistry at the Faculty of Medicine, University of Niš (26 female, 14 male) 21-25 years old, signed consent to voluntarily participate in the research. The Ethics Committee of the Clinic of Dentistry, Faculty of Medicine, University of Niš, approved the study under number 14/11-2019-2EO. They were randomly divided into two groups (n = 20), experimental (IE, individual education) and control (GE, group education). Each group was divided into four subgroups (n = 5). The study was performed in three phases. In Phase I (I) and III (III), students matched the shade of the maxillary central left incisor (#9) using three different shade guides. Each of the students served as a "patient" for shade matching, while the other members of the subgroup, individually (VM_I ) and as a team (VM_T ), visually matched the tooth shade. In Phase II (between phases I and III), group IE received standard group and individual education and training, while group GE had only group education. Shade matching results in before and after education were compared with results obtained by an intraoral spectrophotometer. CIELAB (∆E*), and CIDE2000 color differences (∆E₀₀ ) were calculated. The color differences between VM_I or VM_T and ES readings were graded. In addition, the students rated the level of difficulty and quality of shade matching from 1 to 5, signifying the most to least difficult, and the worst to best match, respectively. Means and standard deviations were calculated. Differences were compared using the Student t-test.

Results: Means (s.d.) of CIEDE2000 color differences for VM_I before and after IE were 4.5 (1.5) and 3.3 (0.9), respectively. Corresponding values for group GE were 4.4 (1.4) and 4.0 (1.0), respectively. As compared with GE, group IE achieved 15% better results for the best matches and 27.5% for one of the three best matches in by-point comparison. Mean (s.d.) results for VM_T in the experimental group before and after IE were 3.6 (2.4) and 2.8 (1.6), respectively. Corresponding results for the control group were 4.4 (2.1) and 3.5 (1.7), respectively. Group IE had statistically higher VM_I and VM_T scores than GE, while, for GE, only VM_T scores were statistically higher. Group IE achieved better results in by-point comparison. After education and training, the students rated the shade matching as more precise and less difficult. Results were significantly better for Quality (IE) (sig = 0.010) and Difficulty (GE) (sig = 0.021).

Conclusions: Within the limitations of the study, the experimental group achieved significantly better results in individual color matching after education and training than the control group, while both groups made progress in team color matching. Both groups rated shade matching more accurate and easier after education.

Clinical significance: Improving the quality of shade matching is expected to enhance the esthetics of dental restorations, increase patient satisfaction, and reduce color corrections.