Dental Furnace Part 2: Test Method for Evaluation of Furnace Program via Firing Glaze | American Dental Association

Dental Furnace Part 2: Test Method for Evaluation of Furnace Program via Firing Glaze

ANSI/ADA Standard No. 164 Executive Summary

What is ANSI/ADA Standard No. 164 about?

This standard determines a degree of firing of a dental furnace. It utilizes a test method for adapting the firing program by determining the degree of firing of fired test specimens for a dental ceramic.

What are the requirements I should know about the test method for evaluation of furnace program via firing glaze?

A different degree of firing does not only cause differences that can be judged directly by the human eye (e.g. color and transparency), but also deviations that cannot be detected by eye. These may include the coefficient of thermal expansion, strength, and solubility of the dental opaque, dentine or enamel materials, and the bonding strength to its substructure. Such changes may result in clinical failures (e.g. fractures) as well as discoloration and changed aesthetics of the dental ceramic restoration.

The test method enables monitoring of the temperature control in the dental furnace by evaluating the firing degree of a dental ceramic and comparing a fired dental ceramic test specimen to a reference sample.

What’s the bottom line?

Dental furnaces are suitable for the manufacturing of metal-ceramic and all-ceramic restorations for use in dentistry. Dental furnaces are particularly used for firing or sintering, respectively, of dental opaques, dentine and enamel materials to the respective compatible substructure materials. The firing result obtained is influenced by the accuracy of the actual temperature, which may be influenced by the different calibration processes and construction material utilized by manufacturers. By comparing the results of test specimens to a reference sample, the quality of ceramics produced at a various heating times and temperatures can be evaluated and the optimum firing program calibrated.