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Box plots representing quality of the learning environment (n = 30; *p < .05; **p < .001; ns, not significant)
Source publication
Objectives
An innovative calibrated bur, aiming to improve precision during reduction of the incisal edge, was recently proposed to guide practitioners during tooth preparation. However, limited information is available concerning its usefulness in dental preclinical education. The aim of this study was to evaluate whether using this innovative gui...
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Citations
... Recently, it has been recommended to control the reduction in dental tissue by using silicone guides [3], the depth-gauge technique [4], the occlusal record technique [5,6], and the trial restoration approach, since the conventional tooth preparation technique did not provide accuracy nor repeatability [7]. Therefore, the three-dimensional reduction in dental tissue constitutes a challenge for clinicians, since it does not allow an intraoperative measurement of the tooth preparation, which can lead to irreversible complications [8,9]. Specifically, Hsu YT (2004) reported that an inaccurate tooth preparation may cause the failure of 2 of 10 both fixed and removable prostheses. ...
The aim of this work was to analyze and compare the tooth structure removal between a free-hand preparation technique and a computer-aided preparation technique using an augmented reality appliance for complete-crowns preparation designs and “root mean square” (RMS) alignment value. Ten upper teeth representatives of all dental sectors were selected from a generic model library as “Standard Tessellation Language” (STL-1) digital files and 3D-printed in an anatomically based acrylic resin experimental model. Then these were randomly assigned to the following tooth preparation techniques: Group A: free-hand preparation technique (n = 5) (FHT) and Group B: computer-aided preparation technique using an augmented reality appliance (n = 5) (AR). Experimental models were submitted to a digital impression through an intraoral scan and (STL-2) uploaded into a reverse engineering morphometric software to measure the volumetric reduction in the planned and performed tooth structure (mm3) and RMS using the Student’s t-test and the Mann–Whitney non-parametric test. Statistically significant differences were observed between the volumetric reduction in the planned and performed tooth structure (mm3) of the AR and FHT study groups (p = 0.0001). Moreover, statistically significant differences were observed between the RMS of the planned and performed tooth preparations in both the AR and FHT study groups (p = 0.0005). The augmented reality appliance provides a more conservative and predictable complete-crowns preparation design than the free-hand preparation technique.
... Factors commonly assessed to evaluate the preparation process include occlusal reduction, presence of undercuts, taper, planar/flat reduction, line angles, smoothness, and preservation of adjacent tooth (28)(29)(30). According to the students' opinions and results, performing occlusal reduction correctly has been considered challenging (31,32). ...
Background: This study aimed to determine the effect of multimedia-based and traditional teaching methods on the quality of dental student preparation by evaluating its smoothness, occlusal reduction, and the presence of undercut in the pre-clinic period. Methods: This study was conducted on 60 pre-clinical dental students, who were divided into two groups of A and B. Group A was trained through Multimedia-based teaching methods, including PowerPoint, instructor demonstration, and procedural videos, and group B was trained by traditional education methods, which only included instructor demonstration. The computer-aided design (CAD) system was used to evaluate the preparation factors of smoothness, presence of undercuts, and occlusal reduction on the second premolar and first molar teeth. Results: A significant difference was found between the frequency of smoothness in two education groups for teeth 5 and 6 (P = 0.026, P = 0.022). However, there was no significant difference between the frequency distribution of occlusal reduction in the two education groups (P = 0.383 and 0.168, for teeth 5 and 6, respectively) and was no significant difference between the undercut frequency in the two education groups (P = 0.365 and 0.078 for teeth 5 and 6, respectively). Conclusions: Based on the results, multimedia-based education can effectively promote two challenging preparation factors, including occlusal reduction and smoothness among pre-clinical students.
... Seven vital teeth (VT) and 3 endodontically treated teeth (ETT) were included (3D files were generated using a technique previously described). 16 Using an intraoral scanner (Trios 3, 3Shape), the 10 prepared typodont teeth were scanned, converted to STL format, and included in a specific clinical scenario. ...
Purpose:
To evaluate whether a concordance assessment (CA) software application is able to assess decision-making in restorative and prosthetic dentistry.
Materials and methods:
Vignettes representing 10 different clinical situations were integrated into a software application. Each vignette included 3D digital models and a short case, as well as 5 therapeutic options rated on a 4-point Likert scale (-2 = strongly contraindicated; -1 = contraindicated; +1 = indicated; +2 = strongly indicated). A panel of 15 dental educators (9 educators from the prosthetic department [PD] and 6 from the conservative department [CD]) had to evaluate the indication of each of the 5 therapies for the 10 vignettes.
Results:
This pilot questionnaire showed good internal consistency on most therapies (Cronbach's α = 0.86), with the exception of more recently introduced therapies (overlay/veneerlay and endocrown). On a maximum score out of 100, the average of CD educators (79.2 ± 3.2) was not significantly different (P = .73) from that of a PD educator (77.8 ± 3.5). Scores ranged from 66.8 to 89.6. Analysis of the expert panel's responses also reported mostly (34/50) a distribution of responses that was characteristic of CA and uncertain situations.
Conclusion:
The present software application was able to reproduce and assess decision-making in dentistry with satisfying internal consistency of educators.
... A large number of other applications based on IOS and 3D files to improve learning and assessment of students during tooth preparation is possible [22][23][24]. It was also proposed to use 3D files as 3D printed educational tools in medical education [25]. ...
Three-dimensional files featuring patients’ geometry can be obtained through common tools in dental practice, such as an intraoral scanner (IOS) or Cone Beam Computed Tomography (CBCT). The use of 3D files in medical education is promoted, but only few methodologies were reported due to the lack of ease to use and accessible protocols for educators. The aim of this work was to present innovative and accessible methodologies to create 3D files in dental education. The first step requires the definition of the educational outcomes and the situations of interest. The second step relies on the use of IOS and CBCT to digitize the content. The last “post-treatment” steps involve free software for analysis of quality, re-meshing and simplifying the file in accordance with the desired educational activity. Several examples of educational activities using 3D files are illustrated in dental education and discussed. Three-dimensional files open up many accessible applications for a dental educator, but further investigations are required to develop collaborative tools and prevent educational inequalities between establishments.
... A large number of other applications based on IOS and 3D files to improve learning and assessment of students during tooth preparation is possible [22][23][24]. It was also proposed to use 3D files as 3D printed educational tools in medical education [25]. ...
Three-dimensional files featuring patients' geometry can be obtained through common tools in dental practice, such as an intraoral scanner (IOS) or Cone Beam Computed Tomography (CBCT). The use of 3D files in medical education is promoted, but only few methodologies were reported due to the lack of ease to use and accessible protocols for educators. The aim of this work was to present innovative and accessible methodologies to create 3D files in dental education. The first step requires the definition of the educational outcomes and the situations of interest. The second step relies on the use of IOS and CBCT to digitize the content. The last "post-treatment" steps involve free software for analysis of quality, re-meshing and simplifying the file in accordance with the desired educational activity. Several examples of educational activities using 3D files are illustrated in dental education and discussed. Three-dimensional files open up many accessible applications for a dental educator, but further investigations are required to develop collaborative tools and prevent educational inequalities between establishments.
Purpose: Most veneers are mixed targeted restorative space (MTRS)-type restorations that are partially within the original tooth and require inconsistent preparation depths. This study aimed to evaluate the accuracy of the preparation depth for MTRS veneer preparation.
Methods: MTRS veneer preparation models were developed using the twisted maxillary central incisor (MCI) as the original tooth and the standard MCI as the waxing. Veneer preparations were performed using freehand (MF), silicone (MS), thermoplastic (MT), 3D-printed uniform (MD), and auto-stop (MA) guides. The prepared and original MCI were scanned and superimposed using a custom-made base. The mean absolute differences (MADs) were measured to evaluate the accuracy of the preparation depth. Statistical analysis was performed using the multivariate analysis of variance (MANOVA) test (α=0.05).
Results: The accuracy of the preparation depth was 0.237±0.090, 0.191±0.099, 0.149±0.078, 0.093±0.050, and 0.059±0.040 mm in MF, MS, MT, MD, and MA, respectively. The MADs between the groups were significant (P<0.05). The accuracy of the trial restoration was 0.140±0.081 mm in the MS, and the accuracy of the guiding tube was 0.055±0.033, 0.036±0.011, and 0.033±0.010 mm in the MT, MD, and MA, respectively.
Conclusions: In MTRS veneer preparation for MCI, tooth preparation guides improved the accuracy of the preparation depth by visualizing the TRS profile and providing clear measurement points. The accuracy of the guide is influenced by its flexibility, and the accuracy of the preparation depth is affected by the accuracy of the measurement points.
Im präklinischen Ausbildungsabschnitt des Zahnmedizinstudiums sollen die Studierenden möglichst umfassend und vielseitig auf die Behandlung von Patienten vorbereitet werden. Bislang zählt die Schienung parodontal gelockerter Zähne nicht zum Ausbildungsspektrum und es gibt kein Übungsmodell, mit welchem diese Art der Versorgung erlernt werden könnte. Ziel dieser Studie war es, Zähne für ein Übungsmodell zu entwickeln, dieses mithilfe des 3D-Druckes herzustellen, sowie zusätzlich die Handhabung von verschiedenen Schienungsmaterialien von ungeübten Behandlern bewerten zu lassen. Es wurden parodontal gelockerte Zähne digital designt und mithilfe eines Stereolithographie 3D-Druckers gedruckt. Insgesamt 43 Studierende des siebten Fachsemesters nahmen im Rahmen des Parodontologiekurses freiwillig an der Studie teil. Es wurden pro Teilnehmer zwei Garnituren Zähne jeweils mit dem Material everStick Perio (GC Dental) und dem Material Ribbond Ultra (Ribbond Inc.) geschient. Die Bewertung der gedruckten Übungszähne sowie der zwei Schienungsmaterialien durch die Teilnehmer erfolgte mithilfe eines Fragebogens unter Nutzung der Schulnoten von 1 (sehr gut) bis 6 (ungenügend). Die geschienten Modelle wurden gescannt und digital verglichen. Die Schienungsübung wurde insgesamt als „gut“ empfunden. Die Realitätstreue der Zahnlockerungen sowie die Repositionierung der Zähne in den Zahnbogen wurden mit der Note „befriedigend“ bewertet. Das Material everStick Perio bekam in der Handhabung die Note „befriedigend“, das Material Ribbond Ultra die Note „gut“. Der Lerneffekt der Übung wurde mit der Note „gut“ bewertet, wobei die Teilnehmer ihre eigenen Fähigkeiten vor dem Kurs als „mangelhaft“ und nach dem Kurs als „gut“ bewerteten. Die digitale Auswertung der geschienten Modelle ergab keinen signifikanten Unterschied zwischen den einzelnen Gruppen, welche sich nach Schienungsmaterial, Erst- oder Zweitversuch der Schienung sowie den einzelnen geschienten Zähnen aufgliederten. Die Anwendbarkeit dieses Trainingskonzeptes wurde bestätigt, da sich aus Sicht der Studierenden ein positiver Lerneffekt zeigte.
Statement of problem
Tooth preparation is a fundamental technique, and inaccurate preparation may lead to excessive irreversible tooth removal or insufficient restorative space. The conventional process depends mostly on operator experience, and variable quality is inevitable. Whether a tooth preparation template would be beneficial, especially for inexperienced dentists, is unclear.
Purpose
The purpose of this preliminary study was to evaluate the application of new digitally designed step-by-step templates to guide tooth preparation.
Material and methods
A laboratory scanner was used to obtain digital scans of dental casts. A 3-dimensional reverse engineering software program was used for the step-by-step digital design. The data for a series of guide templates were imported into a computer-aided manufacturing (CAM) machine for milling. Ten experts and 10 inexperienced dentists prepared teeth on a dentoform in a mannequin head. They were instructed to complete the preparation within 20 minutes both with and without the step-by-step template. The prepared crowns were subsequently scanned with an intraoral scanner, the scans were imported into a preparation evaluation software program, and various indexes were scored. The t test was used to analyze the differences between the 2 methods of tooth preparation in each group (α=.05).
Results
No significant differences were found in total scores with and without the guide templates in the expert group (P=.256), but the scores in the inexperienced group differed significantly between the 2 preparation methods (P<.001). In undercut comparisons, the 2 methods of preparation did not differ significantly in the expert (P=.912) or inexperienced groups (P=.601). However, the scores for taper and occlusal reduction were significantly higher in the inexperienced group when using the guide template (P<.001).
Conclusions
The new digitally designed step-by-step tooth preparation guide template significantly improved the efficiency and quality of tooth preparation for inexperienced dentists when preparing multiple teeth.
Introduction: No commercially available solution to improve the teaching of a crown preparation directly on typodont teeth exists at the moment. To fill this gap and support the supervisors of dental courses, a printable and inexpensive tooth was created for structured self-assessment. The aim of this study was to test this printable tooth under realistic pre-clinical situations. Materials and methods: A two-coloured, double-layer practice tooth was developed. This tooth was consisting of a layer for a correct preparation and the crown. All printed teeth were produced with a stereolithographic printer. 35 voluntary secondyear dental students in the second pre-clinical course in prosthodontics were randomly divided into two groups. All students had experience with typodont teeth and models. The first group was trained on four standard model teeth. The second group used model teeth for the first and fourth attempt and printed teeth for second and third attempt. The preparations of the students were scanned by an in-lab scanner and the surface deviations in contrast to a perfect preparation were measured. The differences between the first and fourth attempt were calculated. Benefits of the printed tooth were also evaluated by a questionnaire using German school grades completed by the students (1 = Excellent, 2 = Good, 3 = Satisfactory, 4 = Adequate, 5 = Poor, 6 = Unsatisfactory). Results: The workflow was feasible and cost-effective regarding the production of the printed teeth. The overall rating of the printed tooth in the questionnaire was good (Ø 2.1 ± 0.22). Students reported different advantages of this method in the free text. The comparison of the preparation between the first and fourth attempt showed that there was a significant better preparation with the printed teeth. The complete preparation had median values of 0.05 mm (Group1: standard model tooth) and −0.03 mm (Group2: printed tooth) (P = .005). Divided into single surfaces, the vestibular and occlusal regions were significantly better. The vestibular surface was 0.11 mm (Group1) and −0.04 mm (Group2) (P = .018). The occlusal surface was 0.13 mm (Group1) and −0.05 mm (Group2) (P = .009). Conclusions: The aim of this study was fulfilled. The printed tooth was tested successfully in a pre-clinical course. The feasibility of this teaching concept was confirmed by the questionnaire and the analysis of the preparation form. A significant difference to a standard model tooth was measurable. The students had the possibility to learn a correct crown preparation on a standardised two-layered tooth with included preparation. This printed tooth enabled the students to control the crown preparation directly on their own.
