Advisor(s)
Ramtin Sadid-Zadeh
Committee Member(s)
Amjad Javed
Chin-Chuan Fu
Nathaniel Lawson
Po-Hsu Chen
School
School of Dentistry
Document Type
Thesis
Department (new version)
Dentistry
Date of Award
9-11-2025
Abstract
Objective: The aim of this in vitro study was to assess and compare retention of 3Y-zirconia crowns cemented to various denture bases including conventionally processed PMMA, milled PMMA, and CR-PEEK. Methods: Denture base cuboids of conventional PMMA, milled PMMA, and CR-PEEK were designed and fabricated with a tooth preparation to receive a zirconia crown with wings, 14 of each specimen. Forty-two molar 3Y-monolithic zirconia crowns were prepared with standardized dimensions (1 mm shoulder margin, 2 mm axial wall height, 20-degree taper) and minimum thickness of 1 mm. Surface area of the intaglio of each crown was assessed in square millimeters (mm2). Each denture base segment was sandblasted, treated with visio.link primer, and crowns were primed with MDP and cemented with dual-cure resin cement. After 24 hours, samples were thermal cycled between 5 and 55ºC for 5,000 cycles. Samples underwent a crown pull test using a universal testing machine. Crown retention force was recorded in Newtons (N) and crown retention strength (MPa) was calculated. Normality was assessed with D’Agostino-Pearson test. Data was analyzed using one-way ANOVA with Tukey post hoc tests. Significance set at α=0.05. Results: The one-way ANOVA revealed significant differences between groups (F= 3.4540, p = 0.04186). The Tukey post-hoc revealed no statistically significant differences between groups. The milled PMMA and conventional PMMA (p=0.0661) as well as milled PMMA and CR-PEEK (0.0730) approached statistical significance. There was no difference in crown retention strength between conventional PMMA and CR-PEEK (p= 0.9988). The crown retentive strengths were highest for conventional PMMA (5.5390 MPa), with CR-PEEK similar (5.5066 MPa), and lowest for milled PMMA (3.9001 MPa). The most common Mode of Failure was adhesive failure, with conventional PMMA failing adhesively to the denture base (75%) while CR-PEEK and milled PMMA failed to the crown (71% and 62%, respectively). Conventional PMMA was the only group to have fracture of the tooth preparation. Conclusions: Bonding zirconia crowns to milled PMMA, conventional PMMA, and CR-PEEK denture bases results in acceptable crown retention strengths, with no significant difference between denture base materials.
ProQuest ID
Recommended Citation
Malyszek, Katherine, "Retention Of 3Y- Zirconia Crowns Cemented To Conventional Pmma, Milled Pmma, And Cr-Peek Denture Bases After Thermal Cycling" (2025). All ETDs from UAB. 7442.
https://digitalcommons.library.uab.edu/etd-collection/7442
