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Updated: Feb 14, 2026
07:57
Sampling and Pretreatment of Tooth Enamel Carbonate for Stable Carbon and Oxygen Isotope Analysis
Published on: August 15, 2018
14.8K
Comparison of Coronal Tooth Reductions Resulting from Different Crown Preparations
The International Journal of Prosthodontics
|February 16, 2018
Summary
Undergraduate dental students' crown preparations resulted in varying coronal tooth structure reductions (CTSRs). Porcelain bonded to zirconia crowns required the most reduction, while full gold crowns were most conservative.
Area of Science:
- Dentistry
- Prosthodontics
- Dental Education
Background:
- Crown preparations are essential for restoring damaged teeth.
- Quantifying coronal tooth structure reductions (CTSRs) is crucial for conservative dentistry.
- Variations in CTSRs can occur based on preparation type and operator skill.
Purpose of the Study:
- To quantify the coronal tooth structure reductions (CTSRs) from various crown preparations.
- To evaluate CTSRs performed by undergraduate dental students in a simulation setting.
Main Methods:
- 76 students prepared 21 typodont teeth each.
- Teeth were weighed and analyzed against reference teeth to calculate CTSRs.
- Calculations were performed for different crown preparation types.
Main Results:
- The largest CTSR was for porcelain bonded to zirconia crowns (50.6%).
- Porcelain bonded to metal (PBM) crowns (44.3%) and PBM fixed partial dentures (32.8%) also showed significant reductions.
- Shell crowns (32.5%) and full gold crowns (24.6%) resulted in lower CTSRs.
Conclusions:
- A wide range of CTSRs was observed across different crown preparation types.
- Undergraduate students' preparations were more conservative than controlled in vitro preparations.
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