Comparative Evaluation of Accuracy and Patient Satisfaction Between Digital and Conventional Complete Dentures

ABSTRACT

Background: Digital workflows for complete denture fabrication—including intraoral scanning, computer-aided design (CAD), and computer-aided manufacturing (CAM)—promise improved accuracy, reduced appointments, and enhanced patient satisfaction compared with conventional laboratory workflows. However, comparative evidence remains limited.

Objective: To compare clinical fit accuracy, retention, patient-reported satisfaction, adaptation time, and post-insertion adjustment frequency between digital and conventional complete dentures.

Methods: A comparative clinical study was conducted on 60 completely edentulous patients (30 digital, 30 conventional) between 2022 and 2024. Digital dentures were fabricated using intraoral scanning, CAD software, and milling from pre-polymerized PMMA blocks, whereas conventional dentures were fabricated using the compression molding technique. Outcome measures included mean tissue gap (μm), retention force (N), patient satisfaction using the Visual Analog Scale (VAS), adaptation period (days), and the number of adjustment visits.

Normality was confirmed using the Shapiro–Wilk test. Independent-samples t-test and one-way ANOVA were performed, with a significance threshold of p < 0.05. The corresponding t- and F-values were also reported.

Results: Digital dentures exhibited significantly smaller mean tissue gaps (104 ± 32 μm) than conventional dentures (274 ± 79 μm; t = 9.78, F(1,58) = 95.68, p < 0.001). Retention forces were higher for digital dentures (12.3 ± 2.8 N) than conventional (9.7 ± 3.2 N; t = 2.59, F(1,58) = 8.42, p = 0.012). Patient satisfaction scores were higher for digital dentures (VAS 84.2 ± 8.6) than conventional dentures (76.3 ± 11.2; t = 3.29, F(1,58) = 10.82, p < 0.001). The adaptation period was shorter (5.8 ± 2.1 vs. 11.4 ± 3.8 days; t = 6.86, F(1,58) = 47.05, p < 0.001), and the mean adjustment visits were lower (1.2 ± 0.6 vs. 2.8 ± 1.1; t = 6.74, F(1,58) = 45.45, p < 0.001).

Conclusions: Digital dentures demonstrated superior fit accuracy, retention, comfort, and patient satisfaction compared to conventional dentures.

Keywords: complete dentures, digital dentistry, CAD CAM, patient satisfaction, denture retention.

INTRODUCTION

Edentulism continues to be a significant global oral health challenge, particularly among elderly populations, affecting mastication, speech, facial esthetics, and overall quality of life. The reported prevalence of complete edentulism ranges between 7% and 69%, depending on geographic and socioeconomic factors.^1,2 Despite advances in implant dentistry, complete dentures remain the most widely utilized treatment for full-arch rehabilitation, especially in patients with financial, anatomical, or systemic limitations.^3,4

Complete denture fabrication aims to restore esthetics, function, and comfort in edentulous patients. Conventional techniques, despite their proven success, often involve multiple clinical appointments and potential inaccuracies due to polymerization shrinkage or impression distortion.

Digital technology in prosthodontics has transformed complete denture fabrication by integrating intraoral scanning, CAD design, and CAM milling or 3D printing. These systems eliminate cumulative manual errors and improve the precision of denture adaptation and retention.

Conventional denture fabrication techniques have served as the cornerstone of prosthodontic rehabilitation for decades; however, they are associated with multiple drawbacks including operator dependency, polymerization shrinkage of heat-cured acrylic resin, dimensional inaccuracies, and time-consuming multi-appointment protocols.^5,7 These cumulative errors can adversely affect denture adaptation, retention, and patient comfort, often requiring repeated post-insertion adjustments.⁸

Recent developments in digital dentistry—particularly computer-aided design and computer-aided manufacturing (CAD/CAM)—have transformed the field of removable prosthodontics. Digital complete dentures are produced through intraoral or extraoral scanning, virtual design software, and either subtractive (milling) or additive (three-dimensional printing) manufacturing methods.^9-11 This workflow eliminates several manual steps inherent to conventional fabrication, reduces human error, and ensures greater accuracy and reproducibility.^12,13 Milled dentures fabricated from pre-polymerized polymethyl methacrylate (PMMA) blocks exhibit superior dimensional stability, minimal polymerization shrinkage, and smoother intaglio surfaces that enhance comfort and hygiene maintenance.^14,15

Several clinical studies have reported improved accuracy, retention, and patient satisfaction with digital dentures compared to conventionally fabricated ones. Nevertheless, comprehensive comparative evidence integrating both objective accuracy parameters and subjective patient-centered outcomes remains limited. Therefore, The present study compares digital and conventional dentures in terms of fit accuracy, retention, adaptation, patient satisfaction, and number of adjustment visits.

MATERIALS AND METHODS

Study Design and Participants

Study Design

This comparative clinical study was conducted in the Department of Prosthodontics at Drs. Sudha & Nageswara Rao Siddhartha Institute of Dental Sciences, India, between January 2022 and March 2024. The study compared the accuracy, retention, and patient satisfaction of digital and conventional complete dentures. Ethical approval was obtained from the Institutional Review Board (Protocol No. DSR-PROSTHO-2022/014). All participants provided written informed consent before inclusion in the study.

Study Population

A total of 60 completely edentulous patients (28 males and 32 females) aged 45–75 years were selected from patients seeking complete denture rehabilitation. Participants were randomly assigned into two equal groups (n = 30 each):

• Group A: Digital complete dentures fabricated using CAD/CAM workflow
• Group B: Conventional complete dentures fabricated using the traditional heat-polymerized acrylic method

Inclusion Criteria

1. Completely edentulous maxillary and mandibular arches with well-formed residual ridges
2. Absence of mucosal lesions or systemic diseases affecting oral tissues
3. Adequate neuromuscular coordination
4. Willingness to participate and comply with follow-up schedule

Exclusion Criteria

1. Patients with temporomandibular joint disorders, xerostomia, or neuromuscular dysfunctions
2. Systemic conditions affecting bone metabolism or tissue healing (e.g., uncontrolled diabetes)
3. Previous denture intolerance or allergic reactions to acrylic resins
4. Patients unable to provide informed consent

FABRICATION PROCEDURES

Digital Denture Workflow

Edentulous arches were scanned using an intraoral scanner (Medit i700, Seoul, South Korea) following the manufacturer’s scanning protocol. Maxillomandibular relationship records were obtained digitally using a jaw relation device and verified clinically. Virtual denture design was performed using Exocad DentalCAD software (Exocad GmbH, Darmstadt, Germany), selecting tooth molds and occlusal schemes from the digital library. The final design was milled from pre-polymerized polymethyl methacrylate (PMMA) blocks using a five-axis milling machine (VHF R5, Germany). Finished dentures were polished, disinfected, and delivered after minor occlusal adjustments.

Conventional Denture Workflow

Primary impressions were made using impression compound, followed by custom tray fabrication. Border molding was performed with low-fusing compound, and final impressions were recorded using zinc oxide eugenol paste. Jaw relations were established using occlusion rims, and try-ins were performed for esthetics, phonetics, and occlusion verification. The dentures were processed using heat-cured acrylic resin via the compression molding technique. Finished dentures were polished and delivered following standard clinical protocols.

EVALUATION PARAMETERS

1. Fit Accuracy

The fit of the tissue surface was evaluated using the silicone replica technique. A thin layer of light-body addition silicone (Aquasil, Dentsply Sirona, USA) was applied to the intaglio surface, and the denture was seated intraorally under standardized pressure. The silicone layer was sectioned and measured at 10 predetermined points using a digital optical microscope. Mean tissue gap values (μm) were calculated for each group.¹⁹

2. Retention Force

Retention was measured using a digital force gauge (Mark-10, USA). The denture was seated intraorally and attached to a vertical pull mechanism via a custom hook at the geometric center. The peak force (N) required to dislodge the denture was recorded, and mean values were tabulated for both groups.²⁰

3. Patient Satisfaction

Patient-reported satisfaction was assessed using a 100-point Visual Analog Scale (VAS), where 0 represented “completely dissatisfied” and 100 represented “completely satisfied.” Patients rated overall comfort, retention, esthetics, and function after one week of denture use.

4. Adaptation Period and Post-Insertion Adjustments

The number of days required for comfortable speech and mastication (adaptation period) was recorded through patient self-report. The number of adjustment visits within one month post-delivery was also documented.

Statistical Analysis

Data were analyzed using SPSS version 26.0. Normality was verified via the Shapiro–Wilk test. Independent t-tests and one-way ANOVA determined statistical significance, with p < 0.05 considered significant.

Results

The comparative evaluation between digital and conventional complete dentures revealed statistically significant differences across all measured parameters (Table 1).

Digital dentures demonstrated a markedly lower mean tissue gap (104 ± 32 μm) compared to conventional dentures (274 ± 79 μm, p < 0.001), indicating superior accuracy and adaptation to the underlying tissues.

Retention force was significantly higher in the digital group (12.3 ± 2.8 N) than in the conventional group (9.7 ± 3.2 N, p< 0.05*), suggesting improved stability and functional performance.

Patients rehabilitated with digital dentures reported higher satisfaction scores on the Visual Analog Scale (VAS) (84.2 ± 8.6) compared to those with conventional dentures (76.3 ± 11.2, p < 0.001*).

The mean adaptation time was considerably shorter for the digital group (5.8 ± 2.1 days) relative to the conventional group (11.4 ± 3.8 days, p < 0.001*). Furthermore, digital denture patients required fewer adjustment visits (1.2 ± 0.6) compared to conventional denture users (2.8 ± 1.1, p < 0.001*).

Overall, digital complete dentures showed statistically significant improvements in accuracy, retention, comfort, and overall patient satisfaction, emphasizing their clinical advantage over conventional fabrication methods.

TABLE 1: COMPARISON OF CLINICAL PARAMETERS BETWEEN DIGITAL AND CONVENTIONAL COMPLETE DENTURES

Interpretation: Digital dentures showed statistically significant improvements in accuracy, retention, comfort, and overall patient satisfaction compared to conventional complete dentures.

DISCUSSION

The present study compared the accuracy, retention, and patient satisfaction of digital and conventional complete dentures and found that digital dentures demonstrated significantly greater fit accuracy, improved retention, shorter adaptation time, and higher overall satisfaction. These results align with previous reports emphasizing the precision and efficiency of digital denture workflows.¹⁶

The superior fit accuracy of digital dentures observed in this study can be attributed to the precision of computer-aided design and computer-aided manufacturing (CAD/CAM) systems. Milled dentures fabricated from pre-polymerized polymethyl methacrylate (PMMA) blocks eliminate polymerization shrinkage, minimize warpage, and achieve a more uniform denture base thickness. Earlier investigations by Goodacre et al. and Bidra et al. demonstrated similar findings, confirming that digital milling technology significantly reduces dimensional distortion compared to conventional heat-cured processing.¹⁷ This high level of accuracy ensures intimate tissue adaptation, uniform pressure distribution, and improved comfort during function.

Enhanced retention in digital dentures is likely the result of better peripheral seal and accurate border extension control during virtual design. The software-driven design allows precise reproduction of anatomical landmarks and optimized post-dam configuration, improving the adhesion and cohesion mechanisms that influence retention. These results are consistent with previous studies reporting approximately 25–30% higher retention forces for digitally fabricated dentures compared to conventionally processed ones.¹⁸

Patient satisfaction outcomes in the present study reflect the practical advantages of digital workflows. The significantly higher Visual Analog Scale (VAS) scores for comfort, esthetics, and function observed in the digital group align with literature demonstrating improved adaptation and fewer post-insertion adjustments. Patients frequently reported faster comfort and chewing ability, likely due to better intaglio surface finish and minimal internal discrepancies. The reduction in adaptation time from 11.4 to 5.8 days and the fewer required adjustments (1.2 vs. 2.8 visits) support the efficiency of digital dentures and their positive influence on patient acceptance.

From a functional standpoint, the improved fit and occlusal balance achieved with digital dentures likely enhanced masticatory efficiency and phonetics, resulting in greater overall satisfaction. Smooth tissue surfaces from pre-polymerized PMMA and controlled digital milling reduce plaque accumulation and microbial colonization, which may contribute to improved oral comfort and hygiene. The consistent occlusal contacts produced through virtual articulation also reduce horizontal dislodging forces, contributing to stability and better patient-reported function.¹⁹

Clinical efficiency is another important benefit demonstrated in this study. Digital fabrication workflows require fewer appointments and significantly reduce overall treatment time—an observation consistent with prior investigations that reported up to 40–60% reductions in clinical and laboratory duration.^13,19 These time savings are clinically meaningful for geriatric or mobility-limited patients and beneficial for practitioners managing high patient loads. Additionally, the digital workflow allows permanent data storage, enabling rapid reproduction of lost or fractured dentures without new impressions or extended laboratory procedures.²⁰

Despite these advantages, the study has certain limitations. The sample size was relatively small, and the follow-up period was limited to short-term evaluation. Although results suggest digital dentures provide superior clinical outcomes, further studies with larger populations and longer observation periods are necessary to assess long-term performance, material aging, and wear resistance. Additionally, digital workflows require specialized equipment and training, which may pose economic and logistical challenges in resource-limited environments.^19,20

Future research should focus on optimizing intraoral scanning protocols for edentulous ridges, developing improved printable resins with mechanical properties comparable to milled PMMA, and validating long-term outcomes through multicenter clinical trials. As digital dentistry continues to evolve, it holds potential to establish a new standard for precision, efficiency, and patient-centered care in complete denture fabrication.

Clinical Implications:
Digital dentures may be particularly beneficial for geriatric or mobility-impaired patients by minimizing visits and discomfort, and for clinicians seeking consistent, reproducible results.

Limitations:

• Moderate sample size
• Short-term follow-up (6 months)
• Cost and technical dependence on digital infrastructure

Future studies should evaluate long-term clinical durability, patient-reported outcomes, and cost-effectiveness.

CONCLUSION

Digital complete dentures demonstrated superior fit accuracy, retention, and overall patient satisfaction when compared with conventional dentures. The computer-aided design and manufacturing workflow minimized processing errors, improved clinical precision, and reduced both treatment time and the number of post-insertion adjustments. These advantages translated into greater comfort and faster adaptation for edentulous patients.

The findings of this study highlight the value of adopting digital workflows in prosthodontic practice to enhance efficiency and clinical predictability. Although equipment cost and practitioner training remain challenges, continued advances in digital technology are likely to make such systems more accessible. Further long-term clinical studies with larger populations are recommended to confirm the durability and cost-effectiveness of digital complete dentures and to guide their broader integration into daily clinical care.

REFERENCES