Table 1. Characteristics of the selected studies in restorative dentistry.

S. no	Author, Year, Country	VR system	Participants	Study design	Tool of assessment	Tested outcome	Results
Abbreviations: AR, augmented reality; CCO, comparative crossover; CCT, case control trial; CS, cohort study; CST, cross sectional trial; DS, dental students; FFB, force feedback; RCT, randomized controlled trial; VR, virtual reality.
1	Urbankova 2010, UK 39	Adjunctive computerized dental simulator (CDS)	(75) 1st year DS	RCT	Class I and II cavity preparation	Timing on exam performance	CDS significantly better than controls on exams 1 and 2 but not significant on exam 3
2	Urbankova and Engebretson 2011, UK 22	Haptic simulator	(39) 1st year DS	CS	Perceptual ability test (PAT) Geometric figures haptic exercises	Accuracy, time, and success rate	Correlation is nonsignificant between PAT and exam scores, and significant between exam scores, time and accuracy
3	Amer et al 2011, United States 42	Interactive dental video game to teach dentin bonding	(80) 1st year DS	RCT	Pre and post written examination Shear bond strength test Students’ perception	Knowledge and clinical skills	No significant difference in knowledge or clinical skills except in wetness of dentine following etching. Students accredited the method of teaching
4	Urbankova et al 2013, UK 31	Complex haptic Simulator	(39) 1st year DS	CST	Haptic exercise of geometric figures Plastic tooth preparations	Accuracy and time Quality of plastic-tooth preparation	Number of failures in haptic exercises showed significant predictor of examination scores
5	Bakr et al 2014, Australia 32	Simodont haptic (3D-VR)	(42) 2nd year DS	CCO Early or late haptic training	pre- and post-psychomotor skills test Pre- and post-experimental and flow questionnaires Class II amalgam preparation on permanent 1st molar	% of target area prepared. Expectations, and attitudes. Quality of prepared cavity	No significant difference in practical test (pre and post) between groups. The system was highly accepted by the students
6	Koo et al 2015, United States 33	Haptic device (SensAble)	(34) 2nd year DS	RCT	Class II amalgam and class III resin Questionnaire	Cavity outline and integrity of adjacent tooth. Subjective evaluation of the simulation	Non-statistically significant post haptic scores. Game-feature of the device made the learning experience more interesting
7	Cox et al 2016, UK 34	HapTEL system	(101) 1st year DS	CS	Virtual caries lesions with increased complexity	% of caries removed, healthy tissue remaining, pulp exposure, and drilling time	% caries tissue removed, healthy tissue remaining, and pulp exposure improved for over 90%
8	San Diego et al 2016, UK 35	HapTEL system	(120) 1st year DS	CST	Carries removal tasks with increasing complexity	% of caries removed; healthy tissue remaining; pulp exposure, drilling time	Significant increase in % of carries removed, less pulp exposure, and less preparation time
9	de Boer et al 2016, Netherlands 36	Simodont Haptic dental trainer	(124) 1st year DS	CCO	Cross-figure preparation Manual dexterity exercise with 2D or 3D vision Questionnaire	Rate of success	3D vision achieved significantly better results than 2D. Over 90% preferred 3D vision
10	Tubelo et al 2016, Brazil 40	Virtual learning object (VLO)	(46) 1st year DS	RCT	Theoretical knowledge and skill practice of zinc phosphate cement	Zinc phosphate cement manipulation after immediate or longitudinal access to VLO	VLO showed significantly higher results in theoretical post-tests and better mechanical properties
11	Shahriari-Rad et al 2017, UK 37	hapTEL virtual dental workstation	(140) 1st year DS	CCT	Objective structured clinical examination (OSCE) and clinical skills examination (CSE)	Students’ psychomotor skills and spatial perceptions	Significant improvement in psychomotor skills. Combined use of hapTEL and conventional phantom-head improved spatial reasoning, fine motor skills, hand-eye-finger coordination and 3D/depth perception
12	Cox et al 2017, UK 38	hapTEL workstations	(138) 1st year DS	RCT	Students’ fine motor-skills	Hand-eye-finger movements (pre-, post-) % of caries removed, pulp exposure, and time Micro-CT scanning of excavated plastic teeth	Significant correlation between the pre- and post-test results, and time with caries removal % and negatively with pulp exposure. Roughness of the preparations varied amongst students
13	Al-Saud et al 2017, UK 12	Simodont VR haptic dental simulator	(63) Participants with no previous dental experience	RCT	Preparation of geometric shapes with device feedback, or instructor feedback or both (IDFB)	Acceptable target removal percentage of all tasks was 70%	Significant differences between groups in overall performance, with IDFB group substantially better in performance and fewer errors
14	de Boer et al 2017, Netherlands 23	Simodont dental trainer	(101) 1st year DS	CCO	Geometric cross preparation with or without force feedback (FFB) Questionnaire	Success if 90% of the red target area removed	Only students with FFB were able to pass the tests. 100% of the students preferred working with FFB
15	Gottlieb et al 2017, United States 41	VR Advanced simulation	(282) DS of three sequential dental classes	CT	Class I and II amalgam preparations and restoration, and Class III and IV composite restoration	Advanced simulation exams scores in operative dentistry and fixed prosthodontics	Advanced simulation exam scores 1 and 2 were predictors of performance in the two preclinical courses based on final course grades
16	Ria et al 2018, UK 24	hapTEL system	(39) 1st year DS	CST	Cavity preparation and caries removal of increasing difficulty	% of tissue removed, pulp exposure, time	Insignificant better performance with the hapTEL system, despite lower scores reported with increased difficulty
17	Mirghani et al 2018, UK 26	Simodont system	(289) Dental students	CCS	Six manual dexterity exercises, to remove a target “red zone”	% score of task completion Drill time (in seconds)	Significant difference in performance between year 1 and years 4 and 5. Year 3 was significantly different to year 5
18	Dwisaptarini et al 2018, Thailand 25	Visuo-tactile virtual reality simulator connected to two haptic devices	(32) 6th year DS	RCT	Pre- and post-training clinical assessment of carries removal on extracted tooth	Performance scores Tooth mass loss and task completion time	Post-training performance significantly improved for both groups with insignificant differences between groups
19	Llena el al. 2018, Spain 13	AR cavity models on computers and mobile devices	(43) 3rd year DS	RCT	Theoretical knowledge before, immediately and 6 mo after training Clinical skills Satisfaction questionnaire	10 theoretical concepts Class I and Class II cavity preparation Students’ satisfaction	Insignificant differences in knowledge between groups but significant in cavity depth and extent for Class I and Class II cavities. Students preferred computers over mobile devices
20	de Boer et al 2019, Netherlands 27	Simodont haptic dental trainer	(126) 1st year DS	CST	Successful drilling with alternating FFB Post assessment questionnaire	A preparation on one block cross-figure Participants’ perception of the study	83% of the students passed the test. Skill transfer from one level of FFB to another was feasible with sufficient training
21	Vincent et al 2020, France 28	haptic simulator (Virteasy)	(88) 1st year DS	RCT	Both groups took final exam on plastic analogue teeth	Cavity preparation	Improvement in the drilling skill of both groups with insignificant differences
22	Murbay et al 2020, Hong Kong 29	VR–based system (Moog Simodont)	(32) 2nd year DS	RCT	Cavity preparation evaluation based on SISTA classification	Prepared cavity depth and width, and marginal ridge integrity	Satisfactory domains were significantly higher in experimental group and no significant difference between the manual and digital methods of evaluation
23	Osnes et al 2021, UK 30	Simodent, HT for removal of carries	(111) 1st year DS and 17 clinical practitioners	CST	Removal of virtual carious lesion spreading along the amelodentinal junction (ADJ)	Precision score	Clinicians were significantly more precise than students in removing caries without excessively removing the noncarious areas