Enhancing color and comfort: A preliminary clinical study on the Dahl approach using 3D printed noninvasive restorations.

STATEMENT OF PROBLEM: Clinical evidence regarding the long-term (up to 24 months) color stability of 3-dimensional printed (3D), noninvasive restorations is scarce, particularly when used to implement the Dahl concept. Whether these restorations meet esthetic requirements over time and how potential discoloration affects patient-reported outcomes remains unclear.

PURPOSE: The purpose of this clinical pilot study was to provide initial clinical evidence on the performance of 3D printed, noninvasive restorations used for the implementation of the Dahl concept, with a particular focus on their long-term color stability and their impact on patient-reported oral health-related quality of life.

MATERIAL AND

METHODS

Five participants with localized tooth wear were included in the study, each treated with 3D printed, noninvasive restorations fabricated from a computer-aided design and computer-aided manufacturing (CAD-CAM) ceramic-filled hybrid composite material. Color change measurements were performed using a spectrophotometer to record L* (lightness), a* (red-green), and b* (blue-yellow) values at 6, 12, and 24 months. Patient-related quality of life was evaluated using the Oral Health Impact Profile (OHIP) questionnaire.

RESULTS

Four participants with 24 restorations were documented. All restorations remained clinically in complete function over the 24-month follow-up. Spectrophotometric analysis revealed progressive color changes over time, with mean ΔE values exceeding commonly accepted perceptibility (ΔE=3.7) and acceptability (ΔE=5.5) thresholds at 12 months (5.84 ±2.59) and 24 months (11.27 ±5.85). Despite the observed discoloration, patient-reported oral health-related quality of life improved after treatment and remained stable throughout the observation period, with high ratings for function, comfort, and esthetics.

CONCLUSIONS

Although 3D printed, noninvasive restorations improved patient-related oral health quality of life, their unfavorable long-term color stability limits their use to long-term interim restorations as advocated by the Dahl concept.