Undercut reproducibility of functional impression materials (tissue conditioners).

Area of Science:

• Dental Materials Science
• Prosthodontics

Background:

• Accurate impressions are crucial for fabricating well-fitting dentures.
• Tissue conditioners are used to capture detailed impressions of the edentulous ridge.
• Understanding factors affecting impression accuracy is vital for clinical success.

Purpose of the Study:

• To assess the accuracy of three commercial tissue conditioners in laboratory impressions.
• To investigate the influence of undercut dimensions and tray relief on impression accuracy.
• To evaluate the effect of impression aging time on the accuracy of poured stone models.

Main Methods:

• Laboratory model of an edentulous ridge used for impressions.
• Three commercial tissue conditioners (FITT, Hydro-Cast, Coe-Comfort) were tested.
• Combinations of undercut dimensions, tray relief, and three tray sizes were employed.

Main Results:

• Increased tray relief significantly improved the accuracy of impressions for all tested materials.
• Aging time from 7 to 24 hours showed minimal effect on the accuracy of stone models.
• Material choice and tray selection interacted with tray relief to influence accuracy.

Conclusions:

• Tray relief is a critical factor for achieving accurate impressions with tissue conditioners.
• The tested tissue conditioners demonstrate varying degrees of accuracy influenced by impression techniques.
• Clinical protocols should optimize tray relief to enhance the fit of dentures fabricated from these impressions.