Variations in linear dimensional accuracy and stability of vinylpolysiloxane-based bite registration materials as a function of different polymerization times

A wide range of commercially available vinylpolysiloxane-based (VPS) bite registration record (BRR) materials having polymerization time (PT) in a range of 30 to 180 s are available for clinical choice, with less evidence of their stability. This in vitro study was aimed at assessing the linear dimensional accuracy/stability of seven VPS-based BRR materials with different polymerization times (30 to 180 s). Four hundred and twenty cylindrical samples (30 mm by 3 mm) [control (60); experimental (360)] were planned from seven [Occlufast Rock (O) (PT 60 s), Defend Superfast (D) (PT 30 s), Jet Bluebite (J) (PT 40 s), Virtual Cadbite (V) (PT 45 s), Clear Maxill Bite (C) (PT 75 s), Primo Regular (P) (PT 90 s), and Mark 3 Regular (M) (PT 180 s)] different types of VPS-based BRR materials and were evaluated for dimensional stability at four time intervals [1 h (accuracy), 24, 72, and 168 h (stability)]. Distances between three horizontal coordinates (p1-p2, p3-p4, p5-p6), producing 3 measurements on each sample, were averaged for each subgroup. A one-way ANOVA rank test followed by Dunn’s post-hoc test allowed comparison of median values between/within groups. Statistical significance was kept at a probability value of less than 0.05 (p ≤ 0.05). Occlufast rock (PT 60s) showed clinical accuracy (≤ 0.11 mm) only at 1 h, indicating poor dimensional stability from 24 to 168 h. Materials with PT ≤ 60 s proved more accurate and stable, except for JetBlueBite [PT 40 s], compared to those with PT > 60. Highest accuracy at 1, 24, and 72 h was observed in Defend Superfast [PT 30s], while Primo Regular [PT 90 s] was more accurate at 168 h. All materials showed significant differences between them at different time intervals. Except for Mark 3, all materials show significant differences in median linear dimensions between 1 and 168 h. Dimensional changes observed were in the form of expansion and contraction. Superfast setting, scannable, and clear VPS-BRR materials with less PT than regular showed higher accuracy and stability till 7 days. Since clinical materials with lesser PT are desired, they are a good choice for making BRRs. Clinically, different treatment options and treatment procedures will require specific BRR material depending upon the requirement of particular treatment or procedure.