Surface chemical modification for enhancing the ion exchange process in ultrathin dental porcelain

Abstract This work aims to study the influence of surface chemical modification and subsequent ion exchange in ultrathin feldspathic dental porcelains with an emphasis on mechanical properties. To achieve this, samples using high‐purity commercial feldspathic dental porcelain were manufactured by lost wax casting in discs with 14 ± 2 mm in diameter and 1.2 ± 0.2 mm in thickness. The surface of dental porcelain was enriched with low‐radius lithium and potassium ions. For the ion exchange process, potassium nitrate (KNO 3 ) and rubidium nitrate (RbNO 3 ) were used. Flexural strength and Weibull modulus were studied. The concentration profile of the ions involved in ion exchange was studied via scanning electron microscopy. The best results were achieved through the ion exchange process using KNO 3 (294 ± 30 MPa) and RbNO 3 (272 ± 35 MPa), demonstrating the possibility of increasing the flexural strength of feldspathic porcelain close to lithium disilicate (259 ± 35 MPa). This level of strength had not been previously observed in feldspathic ceramics.