Facilitating Patient Education Using Intraoral Scan Superimposition

The longitudinal capabilities of IOS superimposition may further enhance its value as an adjunctive OHI tool beyond the single-scan approach evaluated in previous studies. By enabling patients to visualize changes in their oral condition over time, clinicians can monitor progress and pinpoint specific areas of improvement or ones that need more focus. Thus, given recent evidence and the user-friendly design of the chairside Patient Monitoring superimposition software, strong potential exists for using IOS superimposition to educate patients about their condition and reinforce OHI that is imperative to longitudinal treatment success.

Methods

Case Management and Use of Intraoral Scanning

A 32-year-old woman was referred to a practice limited to periodontology and implant dentistry by her general dentist. She presented with the chief complaint, “My gums are bleeding,” and with severe gingival inflammation and pain, for which she was already seeing an oral medicine specialist. Due to the pain associated with her condition, the patient reported feeling unmotivated, skipping brushing and avoiding flossing altogether.

In managing this patient, the use of IOS technology as an interactive, visual tool during OHI reinforced the motivational process throughout treatment. Multiple scans were obtained using IOS following the manufacturer’s guidelines to ensure consistent lighting, angulation, and coverage. The goal with each scan was to capture in detail the gingival margins and soft-tissue contours. A total of eight IOS (n = 8) were taken during the 21-month treatment at various times, including at initial evaluation, nonsurgical therapy, and re-evaluation.

Superimposition With Patient Monitoring

Serial scans were aligned and superimposed using the Patient Monitoring system of the IOS. This system employs best-fit alignment algorithms previously validated for accuracy and reproducibility.⁷ Superimposed scans were analyzed within the software using three artificial intelligence (AI)–supported visualization tools (“Difference Map,” “Comparison Slider,” and “Cross Section”) to assess soft-tissue volumetric and color changes over time.

First, the Comparison Slider allowed for a clear, chairside visualization of positive progress in reducing periodontal disease. Across eight scans taken over 21 months, a steady reduction in red-colored inflammation was apparent as the slider allowed seamless movement between selected scans over time. The interactive 3D aspect of the slider also allowed the superimposed IOS to be viewed from angles that highlighted the decrease in inflammatory tissue volume over time (Figure 1).

The Difference Map also contextualized the magnitude of healing across different areas of the gingiva. Differences between the scans were colored by the volumetric difference in IOS using the gradient scale seen on the right side of Figure 2. Areas with the most severe initial inflammation, such as the gingiva surrounding tooth No. 9, were colored deep red, indicating the most pronounced improvement by the 21-month scan. The Difference Map can be applied to any combination of scans, and at any interval; it can pinpoint specific changes, allowing clinicians to reinforce OHI and maintenance in targeted areas while highlighting improvements.

Finally, the Cross Section tool allows clinicians to select a plane, slice the superimposed IOS scans, and produce a flattened 2-dimensional (2D) cross-section with basic reference lines (Figure 3) that are color-coded beige and blue to differentiate the newer and older IOS, respectively. In the 2D cross-section (bottom right portion of Figure 3), tooth migration was observed alongside a decrease in gingival volume, with changes in tooth position accompanying the return of the gingiva toward a healthier state.⁸

Patient Education

At each appointment, new scans were superimposed onto previous scans using the Patient Monitoring system, creating a comprehensive visual timeline of the patient’s condition. The interactive nature of these digital tools allowed providers to highlight positive progress, pinpoint specific areas of improvement, and motivate the patient to continue adherence to OHI imperative to successful longitudinal disease management.

Results

The superimposition of the eight intraoral scans using the Patient Monitoring software allowed clinicians and patient to visualize positive progress, reinforce OHI instruction, and motivate subsequent adherence. The Comparison Slider provided a chairside visualization of treatment progress, the Difference Map highlighted specific areas and the magnitude of improvement, and the Cross Section demonstrated volumetric changes in targeted areas of the gingiva. Pairing these visuals with motivational interviewing techniques reinforced oral hygiene habits imperative to successful longitudinal disease management.

Discussion

IOS superimposition provides value as a non-invasive method for longitudinal visualization and education for patients whose treatment relies on OHI and at-home care. Chairside visualization of changes via the Patient Monitoring system’s superimposition served as an effective educational tool, reinforcing oral hygiene habits essential to successful oral disease management.

The non-invasive nature of IOS allowed clinicians to evaluate soft-tissue changes without physically disrupting sensitive tissue characteristic of oral disease.^9-13 Importantly for pathology-oriented cases, IOS also captures both morphologic and colorimetric data.¹⁴ In the case presented, the multi-angle capture with consistent lighting enhanced accuracy and standardization when assessing the same area over time. Where improvements between stages were difficult to distinguish in traditional photographs, IOS images taken at similar intervals demonstrated inflammatory differences in greater detail. For a patient whose treatment relied heavily on motivation, seeing these positive changes pictured clearly using superimposition tools chairside during OHI instruction motivated her to continue focusing on proper brushing, flossing, and better management of her oral health.

Although this representative case focused on changes in soft tissue, this technology can also visualize longitudinal changes in hard-tissue surfaces of dentition. One study found IOS superimposition to be effective in detecting small defects using the Difference Map,¹⁵ indicating that the use of IOS superimposition to reinforce OHI in cases of dental caries should also be explored.

The interpretation of these findings is limited by the current lack of research validating the accuracy of the Patient Monitoring superimposition system and its associated tools, specifically in relation to soft-tissue assessment. While the technology provided clinically useful visualization in this case, further studies conducted in controlled settings with standardized imaging protocols and larger study cohorts are needed to confirm its accuracy, reproducibility, and validity, including its role as an educational OHI tool. It is also important to emphasize that IOS superimposition cannot replace conventional periodontal probing. Rather, in patients with gingival inflammation, it may serve as an adjunctive educational tool by enabling more comfortable progress tracking while providing additional color and dimensional analysis.

In the future, for cases relying on the expertise of multiple healthcare providers (oral medicine specialists, general dentists, oral and maxillofacial radiologists, etc.), intraoral scanning also has the potential to facilitate the sharing of comprehensive 3D images of patient progress. Although limited by the availability of IOS, this technology should still be considered during continuing and collaborative care of complex oral health conditions.

Conclusion

This article highlights the use of IOS superimposition, combined with best practices in motivational interviewing, to foster patient education and adherence to OHI throughout the treatment process. Further prospective studies should be designed to confirm the findings of this article.

ACKNOWLEDGMENT

The authors acknowledge the guidance of the Tufts University Department of Biology in supporting the preliminary research through an Independent Research project. Additionally, the authors gratefully thank the Perio Studio team, Rose McKenna and Yuchen Wang, for their constant support and feedback. 

ABOUT THE AUTHORS

Jessica Sun Reilly, BS

Research Associate, Tufts University School of Dental Medicine, Boston, Massachusetts; Private Practice limited to Periodontology and Implant Dentistry, Boston, Massachusetts

Estar Rani Vallapu, BDS, MS

Private Practice limited to Periodontology and Implant Dentistry, Boston, Massachusetts

Nika Mehrnia, DDS

Research Fellow, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, Massachusetts; Graduate Scholar, ADA-Forsyth Institute, Somerville, Massachusetts; Private Practice limited to Periodontology and Implant Dentistry, Boston, Massachusetts

Irina F. Dragan, DMD, DDS, MS, eMBA

Adjunct Associate Professor of Periodontology, Tufts University School of Dental Medicine, Boston, Massachusetts; Lecturer, Department of Oral Medicine, Infection, and Immunity, Harvard School of Dental Medicine, Boston, Massachusetts; Private Practice limited to Periodontology and Implant Dentistry, Boston, Massachusetts