Trueness of milled Zirconia versus milled hybrid ceramic Crowns designed for primary teeth restoration compared to the digitally designed filr: An In Vitro Study

Abstract

Introduction: Stainless Steel Crowns (SSC) are not easily replaced by Zirconia Prefabricated Crowns (ZPC) because of their adaptation problem and risk of fracture and loosening.

Objectives: To assess and compare the trueness of milled zirconia and milled hybrid ceramic crowns designed for primary teeth restoration to a digitally designed file.

Methods: The fourteen extracted primary molars were scanned using an intraoral scanner to obtain digital files of the teeth. The digital files were imported into the Design dental software (TDS) and used to design and mill zirconia and hybrid ceramic crowns using a 4-axis milling machine: 14 zirconia crowns and 14 hybrid ceramic crowns were milled. The milled crowns were fitted onto their corresponding primary molars and evaluated for trueness using Geomagic Control X Software (Control X®, Geomagic, Morrisville, NC, USA). The results were recorded in millimeters.

Results: No significant difference was observed in terms of trueness between the milled zirconia crowns and the milled hybrid ceramic crowns (p>0.05).

Conclusions: Computer Aided Design/Computer Aided Manufacture (CAD/CAM) technology and zirconia/ hybrid ceramic materials can be used effectively in the restoration of primary teeth. The use of the hybrid composite material in this technique provides a highly accurate, quick and esthetic solution for pediatric patients, which can improve their oral health and quality of life.