Evaluation of Dimensional Changes in Stone Casts from Disinfected Elastomeric Impressions Using Coordinate Measuring Machine.

BACKGROUND

Effective disinfection of elastomeric impression materials is vital in prosthodontics to prevent cross-contamination without compromising dimensional accuracy. This study aims to evaluate three-dimensional changes in die stone models derived from three elastomeric materials after treatment with three disinfectants.

MATERIALS AND

METHODS

A 3D-printed master model was used to make 120 impressions with three elastomeric materials: Addition Silicone (Perfit Huge), Condensation Silicone (Zhermack Zetaplus), and Polyether (3M ESPE). Each material underwent four disinfection protocols: no disinfection (T1, control), immersion in 5.25% Sodium Hypochlorite (T2), 2% Glutaraldehyde (T3), and 2% Chlorhexidine (T4) for 10 minutes. Impressions were poured with Type IV dental stone and measured at the canine and molar reference points using a coordinate measuring machine (CMM).

RESULTS

Addition Silicone consistently showed the highest dimensional accuracy across all disinfectants. Polyether recorded the lowest accuracy, especially in the control group (T1). Among disinfectants, 2% Glutaraldehyde (T3) preserved the highest dimensional fidelity, followed by NaOCl and CHX. ANOVA and Bonferroni post-hoc analysis revealed statistically significant differences in the canine region for Addition Silicone (P = 0.044), while other comparisons were not statistically significant.

CONCLUSION

Disinfection does not adversely affect dimensional stability of elastomeric impression materials. In total, 2% Glutaraldehyde demonstrated superior preservation of accuracy, particularly with Addition Silicone. Polyether showed the most dimensional variation, suggesting its hydrophilic nature may compromise stability post-disinfection. Clinical implication suggests selecting Addition Silicone with Glutaraldehyde for optimal results.