Manual dexterity in dentistry: Development and evaluation of a preclinical training program.

OBJECTIVES: The aim of this study was to develop and evaluate the effect of a manual dexterity training program on manual dexterity, perception of self-confidence, quality of cavity preparations, and ergonomic work posture of dental students prior to preclinical training. METHODS: Students in the first year of the undergraduate dentistry program (N = 63) participated in this study. The program consisted of eight phases in which students performed different types of activities. The dependent variables were: manual dexterity assessed by the modified Dental Manual Dexterity Assessment; self-confidence to perform a preclinical procedure using the VAS scale; quality of Class I cavity preparation; angular deviation from the neutral position of the neck, trunk, wrist and distance between the student's eyes and the mannequin's tooth. These variables were evaluated at two different times: before and after the application of the program. The independent variable was the preclinical manual dexterity training program. After meeting the assumption of normality, the paired t-Student test was performed, the significance level was 5%. RESULTS: The results showed a statistically significant difference in relation to manual dexterity (p < 0.001), self-confidence (p < 0.001), quality of cavity preparations (p < 0.001), distance from the eyes of the student/mannequin (p < 0.001), deviation angle of the neutral position of the trunk (p = 0.007) and wrists (p < 0.001), with better results in posttraining. CONCLUSION: It was possible to conclude that, in general, the proposed training positively influenced the self-confidence, dexterity, quality of work, and ergonomics of the evaluated students.

Transition between preclinical and clinical training: Perception of dental students regarding the adoption of ergonomic principles.

OBJECTIVE: This study aimed to evaluate the perceptions of third-year dental students regarding the application of ergonomic principles in the transition between preclinical and clinical training in Restorative Dentistry. METHODS: We conducted a qualitative observational cross-sectional study. The sample consisted of forty-six third-year dental students at São Paulo State University (Unesp), School of Dentistry, Araraquara. Data was collected using an individual interview recorded on a digital voice recorder. A script containing questions related to the process of adaptation of students to clinical care with a view to ergonomic work posture was used. Data analysis was based on the quali-quantitative technique of Discourse of the Collective Subject (DCS), using Qualiquantisoft®. RESULTS: Most students (97.80%) perceived the need for an adaptation period in the transition from the preclinic to the clinic regarding ergonomic posture requirements; a part of them (45.65%) claimed that they still could not adapt, primarily due to the difference between the laboratory and clinic in the workstation (50.00%). Some students suggested longer preclinical training in a clinical environment to facilitate this transition (21.74%). The dental stool (32.60%) and the dental chair (21.74%) were the external factors that contributed most to making this transition difficult. The difficulty of the restorative dentistry procedure (10.87%) also interfered with posture. Additionally, the most challenging ergonomic posture requirements in the transition period were maintaining 30 to 40 cm between the patient's mouth and operator's eyes (45.65%), positioning the patient in the dental chair correctly (15.22%), and working with the elbows close to the body (15.22%). CONCLUSION: Most students perceived the need for an adaptation period in the preclinical transition to the clinic, attributing difficulties to adopt the ergonomic posture requirements, to use the workstation and to perform the procedures on real patients.

Preclinical dental training: Association between fine motor skills and compliance with ergonomic posture techniques.

OBJECTIVE: The aim of this study was to evaluate the dental students' fine motor skills and their compliance with ergonomic posture techniques over the course of a preclinical training year. The correlation between fine motor skills and compliance was also assessed. METHODS: The ergonomic posture of students enrolled in the second year of a five-year undergraduate dental degree programme (n = 62) was assessed using the Compliance Assessment of Dental Ergonomic Posture Requirements (CADEP). This assessment relied on photographs of the students performing preclinical laboratory procedures during the school year. The photographs of each procedure received a score, and the final score obtained (0 to 10) corresponded to the extent of the student's compliance with ergonomic posture techniques. Initial compliance was calculated during the first two months of the training programme, whilst final compliance was calculated during the last two months. Fine motor skills were evaluated using the modified Dental Manual Dexterity Assessment (DMDA), which was also applied at the beginning and the end of the school year. Data were assessed statistically by Student's paired t test, and the correlation between fine motor skills and compliance with ergonomic posture techniques was estimated by Pearson's correlation coefficient (r) and Student's t test (α = 0.05). RESULTS: The compliance scores were higher at the end of the academic year than at the beginning of year (p < 0.001; t = -5.300). Fine motor skills improved significantly with time (p < 0.001; t = -10.975). Non-significant correlations were found between students' fine motor skills and their economic posture compliance both at the beginning (r = -0.197; p = 0.126) and at the end of the training year (r = 0.226; p = 0.078). CONCLUSION: The students' manual dexterity and compliance with ergonomic posture techniques increased over the course of the preclinical training year, and the correlation between students' fine motor skills and their ergonomic posture compliance was not significant.

Development and assessment of an indirect vision training programme for operatory dentistry: Effects on working posture.

OBJECTIVES: Students experience difficulty working with indirect vision and often adopt inadequate working postures because of it. This study created and then assessed the effects of an indirect vision preclinical training programme on dental students' working posture. METHODS: The study enrolled students in the third year of the 5-year undergraduate programme in dentistry in the School of Dentistry of São Paulo State University (UNESP), Araraquara (N = 54). The programme consisted of four training sessions in which students performed different types of activities in which only a mirror was used to see the procedure they were performing. To evaluate posture, students were asked to perform class III cavity preparations (distal-palatal and mesial-palatal preparations) on upper central and lateral incisors in a dental mannequin (tooth numbers 11, 12, 21 and 22) both before and after the indirect vision training programme. Photographs were taken of the students' working postures. The photographs were assessed by a duly trained researcher using the Compliance Assessment of Dental Ergonomic Posture Requirements. A descriptive statistical analysis was performed, and the assumptions of normality were verified. Student's paired t test was also performed. The significance level adopted was 5%. RESULTS: A significant difference was found between the percentages of correct ergonomic postures adopted before and after the training programme (p = 0.039). CONCLUSIONS: The preclinical training programme for indirect vision was found to have a positive effect on the working postures of the students evaluated herein.

Micro-shear bond strength of adhesives with different degrees of acidity: Effect on sound and artificially hypermineralized dentin.

This study evaluates the bond strength of four self-etching adhesive systems with different acidity levels in normal and artificially hypermineralized dentin substrate. Healthy human molars were divided into groups: normal dentin-N (n = 36) and artificially hypermineralized dentin-H (n = 36). Self-etching adhesive systems Clearfil S3 Bond (n = 9), Optibond All in One (n = 9), Clearfil SE Bond (n = 9), and Adhese (n = 9) were used for both the N and H groups. Transparent cylindrical matrices were positioned on the treated dentin surfaces, filled with composite resin, and light-cured for 40 s. After the transparent cylindrical matrices were removed, the specimens were stored for 24 hr in a humid environment at 37°C and were subjected to a micro-shear bond strength test. For each group, a specimen was prepared and evaluated in scanning electron microscope for adhesive interface observation. Normality was confirmed and the two-way analysis of variance and Games-Howell post-tests were conducted (α = .05). The data demonstrated an interaction between the adhesive system and type of dentin substrate (p < .01). For normal dentin, all adhesive systems assessed were adequate; however, in the hypermineralized dentin, the Clearfil SE Bond two-step self-etching adhesive system with mild pH presented the highest immediate bond strength. There was a predominance of adhesive failures for all adhesive systems in the different dentin substrates evaluated. It was concluded that the self-etching adhesive systems evaluated were efficient for both substrates, and for the hypermineralized dentin, the Clearfil SE Bond presented a higher bond strength value.

Preclinical dental training: Association between difficulty in performing restorative procedures and the adoption of ergonomic posture.

OBJECTIVE: The aim of this study was to determine any correlations between difficulty in performing restorative procedures and the adoption of ergonomic posture by dental students in a preclinical course. METHODS: The sample was composed of second-year undergraduate students enrolled in the School of Dentistry of São Paulo State University (UNESP), Araraquara (n = 56). The data were collected from weekly records in which students who had participated in training in a preclinical restorative dentistry laboratory registered the difficulty they experienced performing given proposed preclinical procedures and adopting ergonomic posture (positioning of students' legs, thighs, spine, arms, and forearms, as well as the positioning of both the dental light and the dental mannequin's head, the distance between the operating field and the operator's eyes, and the location of the instruments used in the procedures). Answers were provided on a scale of zero to ten points (zero = no difficulty; 10 = maximum difficulty). A descriptive statistical analysis was performed. The correlation between the level of difficulty in performing the restorative procedures and in the adoption of ergonomic posture was estimated using the Pearson correlation coefficient (r), and its significance was tested using Student's t test. To evaluate the effect of time on students' perceived difficulties in implementing ergonomic posture, the first 2 weeks of training was defined as the initial time, whilst the last 2 weeks was defined as final time (scores from these periods were averaged). After the normality assumptions were verified, Student's t test for paired samples was performed. The significance level adopted was <5%. RESULTS: A correlation was found between the difficulty students experienced performing the preclinical procedures and their difficulties implementing ergonomic posture; the correlation was significant, though the correlation ranged from slight to moderate (P < 0.001; r = 0.38-0.63). In addition, the data also showed that the students' perceptions of how difficult it was to implement these posture items decreased significantly over time (P < 0.001). CONCLUSION: The correlation between perceived difficulty in performing the preclinical restorative dentistry procedures and the application of ergonomic posture was slight to moderate, and the students' perceived difficulties in maintaining ergonomic posture decreased over the course of the school year.