The Application of Virtual Simulation Technology in Scaling and Root Planing Teaching

Abstract

Background

Virtual simulation (VS) technology has been widely utilised in various aspects of oral education. This study aimed to evaluate the impact of VS technology in a scaling and root planing (SRP) teaching programme and explore an effective teaching approach.

Method

A total of 98 fourth-year undergraduates from Guanghua School of Stomatology at Sun Yat-sen University were enrolled in this study and randomly assigned to either the VS teaching group or the traditional teaching (TT) group. All participants received SRP training before undergoing an operational examination. Subsequently, questionnaires were administered to both students and teachers involved in the programme to assess the teaching effect and fidelity of the VS training system. Unpaired Student t test was used to analyse the final test scores and residual rates amongst students.

Results

The overall residual rate of the calculus in the VS group was significantly lower than that in the TT group (48.81% ± 13.50% vs 56.89% ± 13.68%, P<.01). The difference was particularly notable in posterior teeth, proximal surfaces, and deep pockets. Additionally, the VS group students achieved higher final grades compared to the TT group (86.92 ± 6.10 vs 83.02 ± 6.05, P<0.01). In terms of teaching effectiveness assessment, the VS group students provided higher scores than the TT group, except in the areas of mastery of position, finger rests, and efficiency.

Conclusions

The implementation of VS technology demonstrated improvements in students’ performance in SRP teaching. Therefore, a novel integrated pedagogic approaches method that combines VS technology with traditional teaching approaches could be further explored in future training programmes.

Introduction

Periodontitis is a significant public health issue that leads to irreversible damage to the supportive structures and eventual tooth loss.¹ Moreover, it is closely linked to systemic diseases, such as diabetes and cardiovascular disease.² Subgingival scaling and root planing (SRP)—aimed at eliminating subgingival dental plaque and calculus, which are key pathogenic factors in periodontitis—plays a crucial role in altering the local ecological environment and reducing inflammation.^3,4 SRP is recognised as the most effective nonsurgical periodontal therapy and an essential treatment for all patients with periodontitis.⁵

SRP is an essential clinical skill for dental students and represents a central and challenging aspect of periodontology education. Proficiency in SRP necessitates dedicated training, a comprehensive grasp of periodontal scaler design and composition, mastery of patient positioning and fulcrum placement, as well as a delicate tactile sense to detect subgingival calculus.

However, the effect of current teaching is significantly hindered by time constraints and the lack of sustainable materials. A nationwide survey on curriculum design and students’ feedback in Chinese dental schools showed that the allocated time for periodontology courses was insufficient.⁶ Traditional jaw models, commonly used for dental skill training, have several limitations including the absence of timely feedback, difficulties in presenting complex 3-dimensional geometry clearly, and distorted haptic perception of plastic gingiva and teeth. Therefore, it is imperative to explore new, effective teaching methods for subgingival scaling.

The video-assisted debriefing teaching mode was reported to enhance teaching efficiency; however, it still lacks a comprehensive teaching environment and appropriate hardware.⁷ Thus, there is ample room for the integration of multisensory technology, which can stimulate the brain more effectively and provide realistic and engaging environments.⁸ Another study demonstrated that incorporating haptic, auditory, and visual sensations in preclinical periodontal training can reduce postoperative complications and improve patient treatment outcomes. Multisensory assessment and feedback can help students establish a connection between their actions and the desired outcomes.⁹ Currently, this concept has had a profound influence on the development of dental simulators.

Virtual simulation (VS) technology has the capability to replicate real-world scenarios, creating an immersive and sustainable learning environment. This enables students to practice with the assistance of timely feedback and self-correction, facilitating the development of skill competency at a low cost.^10,11 The force feedback provided by dental simulators also offers a realistic haptic perception, allowing dental students to better master scaling forces. This technology has proven to be effective in enhancing hand–eye coordination and spatial reasoning skills amongst students.¹² The simulators maintain a 1:1 movement ratio between the virtual tools and the haptic tools, enabling students to acquire the necessary fine hand dexterity required in real clinical situations.¹³ Furthermore, VS technology provides a wide range of clinical scenarios involving different patients and disease states, as well as their simulated responses to treatment errors, thereby enriching the learning experience for students.¹⁴

VS has already become an integral component of oral education, encompassing areas such as tooth preparation, cavity detection, and oral implant therapy. Previous research has shown that the combination of virtual reality (VR) and jaw models can significantly improve students’ performance in supragingival scaling.¹⁵ However, the effectiveness of VS technology in subgingival scaling has yet to be clearly elucidated. The objective of this research is to evaluate the impact of VS technology on subgingival scaling instruction during the pre-practicum periodontology phase.

Materials and methods

Experimental participants

Ninety-eight fourth-year undergraduates from Guanghua School of Stomatology at Sun Yat-sen University were enrolled as participants in this study. The selection criteria included the following: (1) being fourth-year dental students, (2) having no prior training in SRP, (3) participating voluntarily, and (4) selected randomly based on student ID. Participants who were unable to complete the 2-day trial were excluded from the study. The whole process was carried out under the protocol approved by Medical Ethics Committee of Hospital of Stomatology, Sun Yat-sen University (KQEC-2023-63-01).

Randomisation and blinding

The participants were randomly assigned to either the VS group and traditional teaching (TT) group in a 1:1 allocation ratio, utilising sealed opaque envelopes. Teachers who graded the students were blinded to the group assignments.

Sample size

Sample size was calculated according to the formula: N$={\left[\frac{\left(Z_{\alpha /2}+Z_{\beta }\right)s}{\delta }\right]}^2\left(Q_1^{-1}+Q_2^{-1}\right)$. The significant level α was set at 0.05, and the statistical power of test 1-β was set at 95%. According to our preliminary experiment, s = 0.104 and δ = 0.118, so the sample size of the present study was determined to be 40.47. At the end, 49 participants were enrolled in each group.

Experimental material

Periodontal pathologic models (Nissin Dental Products Inc.), Gracey curettes (Hu-Friedy 5/6, 7/8, 11/12, 13/14) (Figure 1A) and UniDental Simulators (Beijing UniDraw Virtual Reality Technology Research Institute Co., Ltd.) (Figure 1B) were used in this study.

Fig. 1.

Overview of the virtual simulation (VS) system and pathologic model. A, Periodontal pathologic models and Gracey curettes used in this study. B, Overview of UniDental VS system. C, Main functional interface of scaling and root planing in VS training programme. D, Demonstration of scaling and root planing of an anterior tooth in VS training programme. E, The training process of UniDental VS system. F, The training process of pathologic model on the jaw simulator.

Experimental methods

All participants completed theoretical learning in the same classroom. Subsequently, the dental simulator was used in VS group for subgingival scaling training (Figure 1B). The training session encompassed various components, including position, finger rest, adaptation, instrumentation stroke, and integrated regional training (Figure 1C). Through the control panel, students were able to select different clock positions corresponding to specific treatment areas. The “finger rest” module provided instruction on instrument grasp and proper finger rest technique, allowing students to practice holding the instrument and using the finger rest correctly. In the “adaptation” module, students were trained to position the first 1 to 2 mm of the working-end's lateral surface in contact with the tooth. Manipulating the position and orientation of the virtual dental instrument was achieved by utilising a haptic stylus (Figure 1D, E).

In TT group, instructors performed the demonstration. Then, each student was allowed to train on the pathologic TT model (Figure 1F). The teacher made circuits in the lab to correct students’ missteps. The training time between VS training and TT were the same.

The next day, all participants were asked to perform a subgingival scaling on 6 particular teeth (#11, #16, #17, #31, #37, #46), of which all 4 surfaces (buccal, lingual, mesial, and distal) were scaled. The residual rates were expressed as percentage of the number of tooth surfaces with residual calculi to the total number of tooth surfaces. In addition, the final scores based on students’ comprehensive performances were recorded (Supplementary Table 1).

Questionnaire survey

Questionnaires were distributed to all 98 students and 5 teachers. The teaching effectiveness questionnaire consisted of 12 items, assessing students’ mastery of various aspects such as position, fulcrum, and fitting angle (Supplementary Table 2). Another questionnaire focused on the fidelity of the VS system was completed by the students in VS group and the teachers (Supplementary Table 3). All of them rated their responses on a 5-point Likert scale, ranging from 1 = strongly dissatisfied or strongly disagree to 5 = very satisfied or strongly agree.

Statistical analysis

The residual rate of the calculi of subgingival scaling was expressed as a percentage using the following formula: (1-$\frac{Thetotalofclearsurfaces}{Thetotalofallsurfaced})\times 100\%$. Data were expressed as mean ± SD. A comparison of the 2 groups was conducted using an unpaired Student t test. A P value <.05 was considered statistically significant.

Results

Comparison of the residual rates between the 2 groups

A total of 98 fourth-year students with a mean age of 22 years, enrolled in Guanghua School of Stomatology at Sun Yat-sen University, participated in this study. After completing the theoretical course, the students took a quiz on periodontology knowledge and the scores were recorded as the theoretical learning score. There were no statistically significant differences in theoretical learning scores or male:female ratio between the 2 groups (Table). The study involved a total of 588 teeth with 2352 surfaces. The overall residual rate in the VS group was significantly lower than that in the TT group (48.81% ± 13.50% vs 56.89% ± 13.68%, P<.01) (Figure 2A). Furthermore, a stacked bar chart demonstrated that the variation of residual rates was greater in the VS group than in the TT group (Figure 2B).

Table.

Demographic description of students in the virtual simulation (VS) and traditional teaching (TT) groups.

	TT	VS
Age, y	22.490	22.449
Female:male	35:14	32:17
Theoretical scores	84.86	86.14

Fig. 2.

Comparison of the residual rate and assessment score in the virtual simulation (VS) group and traditional teaching (TT) group. A, Comparison of the overall residual rate of subgingival scaling. B, Stacked bar chart showing the distribution of different grades of residual rate of subgingival scaling in the VS group and TT group. C, Comparison of the residual rate of subgingival scaling at different regional sites in the VS and TT groups. D, Comparison of the residual rate of subgingival scaling of different tooth surfaces. E, Comparison of the residual rate of subgingival scaling in different depths of periodontal pockets. F, Comparison of assessment score between the VS and TT groups. G, Stacked bar chart showing the distribution of different grades of assessment score in the VS group and TT group.

Next, the study compared the effectiveness of calculi removal in different segments of the dentition, on different tooth surfaces, and at varying depths of periodontal pockets following subgingival scaling. First, the residual rates in anterior teeth were lower than the posterior (45.92% ± 16.23% vs 56.31% ± 15.27%, P<.01). Compared to the TT group, the residual rates of the VS group were lower both in anterior (41.84% ± 15.84% vs 50.00% ± 15.73%, P = .01) and posterior teeth (52.30% ± 14.13% vs 60.33% ± 15.44%, P<.01) (Figure 2C).

Similar findings were observed when comparing different tooth surfaces. The residual rates of buccal-lingual surfaces were lower than those of mesiodistal surfaces in both groups (43.88% ± 14.63% vs 61.82% ± 17.87%, P<.01). Compared to the TT group, the VS group demonstrated greater advantages in calculus removal on mesiodistal surfaces (56.97% ± 18.35% vs 66.67% ± 16.14%, P<.01) compared to buccal-lingual surfaces (40.65% ± 13.46% vs 47.11% ± 15.17%, P = .03) (Figure 2D).

When examining the residual rates amongst periodontal pockets of different depths, it was observed that the VS group had lower residual rates compared to the TT group in shallow (31.38% ± 20.27% vs 40.82% ± 21.16%, P = .03), medium (55.10% ± 10.73% vs 60.88% ± 12.75%, P = .02), and deep periodontal pockets (64.80% ± 23.34% vs 77.04% ± 24.91%, P = .01) (Figure 2E). The difference between the 2 groups was 9.44% and 5.78% in the shallow and medium pockets, respectively. Furthermore, the difference increased as the depth of the periodontal pocket deepened, as it was 12.24% in the deep pockets.

Comparison of the final assessment scores between the 2 groups

Students’ SRP performances were scored by teachers using a standardised scale (Supplementary Table 1). The scale comprises instrument choosing, position, probing, instrument grasp, finger rest, angulation of instrument during subgingival insertion, and so on. The total scores in the VS group were significantly higher than those in the TT group (86.92 ± 6.10 vs 83.02 ± 6.05, P<.01) (Figure 2F). The distribution of scores is depicted in the stacked bar chart in Figure 2G.

Comparison of the teaching effects assessed by questionnaires between the 2 groups

Scores of students in the VS group on various aspects, such as mastery of adaptation, angulation for insertion, lateral pressure for calculus removal, sliding movement, instrument grasp, approach of working end, sequence, and reducing dental and gingival injury, were significantly higher compared to students in the TT group (P<.01). However, in terms of mastery of position, finger rest, scaling effectiveness, and students’ evaluations, the TT group outperformed the VS group (P<.01) (Figure 3A).

Fig. 3.

Feedback of questionnaires from students in virtual simulation (VS) and traditional teaching (TT) group and teachers. A, Students’ evaluations of teaching effects from the VS and TT group. B, Feedback of the fidelity of the VS system between male and female students. C, Feedback of the fidelity of the VS system between teachers and students.

*a-h in Figure B and C refer to the fidelity of shape and colour of teeth, gingiva and calculus, shape and colour of dental tools, shape and colour of oral environment, magnitude and direction of power, allowable moving range and orientation range of offset blade, stiffness and friction of teeth and gingiva, the feeling of calculus peeling off the teeth surface, and response of virtual patients.

Feedback of the fidelity of the VS system

The results showed that males gave higher ratings on shape and colour of teeth, gingiva and calculus, shape and colour of oral environment and magnitude and direction of power (P<.01) (Figure 3B). However, in stiffness and friction of teeth and gingiva (P<.01) and the feeling of calculus peeling off the tooth surface (P = .02), females scored higher than males. Furthermore, when comparing scores given by teachers and students, teachers gave lower ratings on the fidelity of shape and colour of dental tools (P<0.1), shape and colour of oral environment (P<.05), allowable moving range and orientation range of offset blade (P<.01), and response of virtual patients (P = .01) (Figure 3C).

Discussion

SRP holds significance not only as a vital periodontal skill in clinical practice but also as a fundamental component of preclinical teaching. Traditional teaching methods relied on practice using pathologic models, combined with theoretical learning and demonstrations by instructors. However, this approach often hinders the development of self-assessment abilities and critical thinking amongst students.¹⁶ Moreover, the traditional teaching approach is associated with challenges such as the wear and tear of pathologic models and artificial teeth,¹⁷ limitations in providing an authentic tactile experience,¹⁸ and difficulties in representing the complex interaction between teeth and gums.

In recent years, the integration of VS technology and dental simulators has revolutionised the pedagogic approach in undergraduate oral education. This innovative approach allows for repetitive training sessions without patients.¹⁹ The primary objective of this study was to assess the effectiveness of VS technology in teaching periodontal subgingival scaling and then to explore a novel and efficient method for delivering subgingival scaling instruction.

The findings of this study revealed that the utilisation of VS technology in SRP significantly enhanced students’ proficiency in calculus removal and reduced residual rates, particularly in challenging areas such as posterior teeth, proximal surfaces, and deep periodontal pockets. The variation of the residual rate is also greater in VS group, suggesting that teaching with VS technology could inspire students to perform at their highest potential. Several factors may account for these outcomes. First, in SRP, where calculus is situated beneath the gingival margin, the ability to perceive tactile feedback is crucial for accurately locating and removing calculus deposits.¹⁸ By incorporating haptic technology into the opaque model, students can experience realistic tactile sensations while assessing calculus on the root surface. Additionally, the visualisation of the gingival tissue enables simultaneous visualisation of calculus deposits below the gumline.²⁰ Second, students benefited from real-time feedback, enabling them to promptly identify and rectify any errors accordingly.²¹

It is notable that students in VS group also demonstrated improved performance in adaptation. Maintaining proper adaptation throughout instrumentation is crucial for successful subgingival scaling, which is particularly difficult for novice clinicians. Due to the invisibility of subgingival scaling training, trainers cannot monitor the real-time positioning of the working end. In contrast, the VS system enables trainers to continuously observe the positioning of the working ends and receive immediate haptic feedback. The synchronised visual and haptic feedback facilitates the establishment of a connection between the visual cues and tactile sensations in the students’ minds, enabling them to effectively utilise tactile feedback to ensure accurate instrumentation in realistic clinical scenarios.

Furthermore, the results indicated that students in the VS group demonstrated superior performance in minimising damage to both soft and hard tissues. This can be attributed to the design of the virtual gingiva, which provides a realistic representation of the actual structures. Unlike silicone rubber gingiva, which is challenging to penetrate, the virtual gingiva is engineered with appropriate compliance and texture to make it more movable and flexible to enhance realism.²² As a result, when using curettes on the tooth surface, the virtual patient exhibits immediate responses such as slipping of the instrument and simulated gingival damage, thereby aiding students in establishing a connection between extrinsic feedback and their operational techniques. This linkage reinforces the students’ empathy awareness and promotes skill development. The VS system is also characterised by clinical situational representation. When gingiva is damaged, the VS system will emit a danger alarm and tongue will dodge reactively. Students are asked to comfort the patients in the virtual scenario, assisting them to improve their communication skills and patient-friendly consciousness.

However, the VS system also presents certain limitations. First, VS students gave lower scores than TT students on their mastery of finger rest. A stable finger rest is of great importance in SRP to hold and strengthen.²³ Second, VS students gave lower scores on their mastery in position. In the “position” module, students could only select the correct clock position for different treatment areas. However, repeated seated position practice under monitors and getting bodies used to clinical situation is more important than theoretical principles. Third, teachers rated the fidelity of the VS system lower than the students did. This implies that the dental simulator may be better suited for novice trainees and that there is still ample room for improvement to expand its adaptation range and provide a more realistic experience for advanced learners. These limitations highlight areas that can be addressed and improved upon in future iterations of the VS technology and dental simulator, ultimately enhancing its effectiveness and suitability for a broader range of dental education levels and scenarios.

The evaluation of the fidelity of the VS system by gender is an aspect worth discussing. Previous studies reported that females had higher tactile thresholds than males.²⁴ This difference in tactile sensitivity could potentially explain why females rated the fidelity of stiffness and friction of teeth and gingiva higher than males. It is generally believed that women have superior colour sensitivity to men's.²⁵ Therefore, it is reasonable to consider that females gave lower scores on the fidelity of VS system of shape and colour of teeth, gingiva, calculus, and oral environment. Further exploration and understanding of these gender-based differences can contribute to the refinement and customisation of VS technology to better cater to the diverse needs and perceptions of both male and female dental students.

Overall, both traditional methods and VS technology seem to have their own merits. Thus, we proposed the concept “integrated pedagogic approaches,” which combines the 2 methods in order to maximise their strengths (Figure 4). Previous research by Zhang et al¹⁵ demonstrated improved performance in supragingival scaling when VS was combined with a jaw model. In our proposed integrated pedagogic approaches, students would begin with a 15-minute theoretical lecture and a 25-minute demonstration on the model. Subsequently, they would engage in training on the VS system, focussing on practicing adaptation, instrument grasp, and force control. Following this, students would have hands-on practice on the model to emphasise proper positioning and finger rests. With advancements in technology, the use of virtual patients could also be incorporated in the clinical training sessions.²⁶ When students engage in the clinical stage, they will also practice on the VS system and undergo operation assessment every 2 weeks.

Fig. 4.

Schematic diagram of integrated pedagogic approaches.

There are several limitations of this research. First, the effect of the integrated pedagogic approaches of 2 methods still needs to be explored. Second, the long-term effect of the VS system is still unknown. There is a time gap between the preclinical training and the laboratory course, so it would be valuable to investigate the effects of this new teaching strategy during students’ preclinical stage to assess its long-term benefits.

Conclusions

To sum up, students in the VS group perform better and expressed satisfaction with the teaching effects. Based on these results, a novel teaching approach combining the strengths of VS technology and TT methods warrants further investigation and development in the field of subgingival scaling education.

Author contributions

All authors made substantial contributions to the present study. CZ and PW contributed to conception and design of the study. LG, PW, and SW participated in acquisition of data and analysis and interpretation of data; they were, moreover, involved in writing and editing the manuscript. LG and SW contributed with the acquisition of data, evaluated all data, and made the statistical evaluation. JF participated in the design and analysis of the materials and drafted the manuscript. All authors read and approved the final manuscript. SW and LG contributed equally to this work and should be considered joint first authors. CZ and PW contributed equally to this work.

Funding

This study was supported by Undergraduate Education Quality Program of Sun Yat-Sen University (Academic Affairs [2022] No. 20) and Guangdong Province 'New Medical Science' Education Steering Committee 2023 Teaching Reform Project.

Conflict of interest

None disclosed.