Table 4. Characteristics of the selected studies in prosthodontics.

S. no	Author, Year, Country	Technology	Participants	Study design	Assessment tool	Tested outcome	Results
Abbreviations: CES, competency exam scores; CCO, comparative crossover; CT, comparative trial; CST, cross sectional trial; DS, dental students; RCS, retrospective cohort study; RCT, randomized controlled trial; VR, virtual reality.
1	Kikuchi et al 2013, Japan 58	DentSim, VR simulation (VRS)	(43) 5th year DS	RCT	Porcelain fused to metal crown preparation	Total scores included 12 preparation items and time	VRS scores were significantly higher. Instructor’s feedback did not result in significant difference within VRS groups
2	Hamil et al 2014, United States 59	Surface mapping technology E4D for students’ grading	(81) DS	CST	Students’ perception questionnaire	Students’ attitudes on the effectiveness of software in developing clinical skills	Students preferred digital grading over traditional and found the software helping them to understand their deficiencies
3	Eve et al 2014, United States 60	3D immersive haptic simulator	(12) novice DS, (12) experienced prosthodontics residents	CT	Simulated caries removal exercise	Percentages of carious lesion removed, and volume of surrounding sound tooth structure removed	Efficiency of carries removal improved significantly for both novice and experienced subjects
4	Callan et al 2014, United States 61	E4D Laboratory works virtual simulation using CAD/CAM technology	(76) 2nd year DS	RCT	CES within the intervention group (1st effectiveness analysis) and between the two groups (2nd efficacy analysis)	Full gold crown preparation on tooth #30. Students’ scores before and after using E4D and using E4D versus not. Post training and post-exam survey	1st effectiveness analysis showed no difference in outcomes. 2nd efficacy analysis showed insignificant higher mean competency scores of CAD/CAM group. Students appreciated the subjectivity of system’s evaluation and the beneficiary in tooth surfaces reduction
5	Lin et al 2018, United States 56	3D instructional models’ application on smartphones	(90) 2nd year DS	CST	Instruction models on rest seat preparation then a questionnaire	Evaluate students’ usage and perceptions of the digital models	73% of the participants who viewed the models responded either agree or strongly agree to the benefits of the models
6	Liu et al 2018, China 62	Online Peer-Review System (OPRS) and Real-time Dental Training and Evaluation (RDTES)	(66) 4th year DS	RCT	Post-training preparation of an anterior ceramic crown on phantom model Questionnaires	Pre-defined 15 evaluation criteria of the ceramic crown preparation Students’ attitude	Digital group was significantly better than the traditional group and 96.97% of it agreed or strongly agreed on the clinical benefits of the system
7	Kozarovska and Larsson 2018, Sweden 63	Digital tool for preparation Validation (PVT)	(57) 3rd year DS	CCO	All-ceramic crown in anterior teeth “prep. and scan” or “best of three” Students’ questionnaire and teachers’ opinions	The level of agreement between the students’ self-assessment and the information from the PVT	“prep-and- scan” showed increase in agreement from attempt one to three, with PVT. In “best of three” lower levels of agreement. Students rated PVT positively and teachers’ feedback suggested improvement modifications
8	Nagy et al 2018, Hungary 64	Dental Teacher software	(36) 4th year DS	RCT	Ceramic mesio-occluso-buccal on lay in a plastic model, scanned and assessed by Dental Teacher software	Six cavity evaluation parameters	Three of the six cavity dimension parameters improved significantly in the test group
9	Liu et al 2020, China 65	Virtual Real-time dental training and evaluation System (RDTES)	(57) 5th year DS	CST	Ceramic crown preparation, pre- and post-learning assessment Questionnaire	Instrument selection, preparation section, reduction, surface and profile	Mean total outcome score after VR training was significantly higher except in mean error score. 97% agreed or strongly agreed that the virtual system could improve their practice
10	Tang et al 2021, China 66	Digital real-time evaluation system (DCARER)	(60) DS, (73) Prosthodontic residents, (10) faculty members	RCT	Crown preparation process and final scores Questionnaire	Agreement between DCARER scores and expert Comparison between groups’ crown preparation scores	Insignificant differences between DCARER and experts’ scoring Tooth preparation scores of the traditional group were significantly lower. More students in the digital group believed the judgment of DCARER is more objective
11	Serrano et al 2020, Netherlands 3	HT models of real patients added in Simodont	(10) 4th and 5th year DS	CST	Training on real patient-haptic volumetric models, then in real patient Final open answer survey	Perceived learning value of the technology and self-assessed confidence and limitations	Identifiable five dimensions of the main features of VR: added value, competence development, self-efficacy, outcomes, and room for development
12	Mai et al 2020, Korea 57	3D simulated graphic dental models and computer designed Software	(60) 2nd year DS	RCT	After the course, 1. An attitudinal survey 2. Final examination	Assessing the preference of participants Knowledge test on the principles of adjustment of deflective occlusion	Students’ feedback indicated that the 3D simulation method was effective in acquiring knowledge on occlusion. Examination scores were significantly higher in the 3D simulation group
13	Al-Saud et al 2020, UK 67	Simodont haptic simulator	(72) 4th year DS	RCS	Students’ scores at year 2 on traditional training or haptic VR training	Full crown test preparation on patient in year 4	VR haptic simulator assessment score was a significant predictor of clinical crown performance