Conclusion. Multilayered zirconia materials manufactured with different yttria contents by layer have reduced flexural toughness than Those people made with gradient shade technologies and the exact same yttria articles for each layer. For that reason, numerous elements like the style of prostheses, nesting tactics of prostheses within the zirconia disc, https://www.directivepublications.org/journal-of-dentistry-and-oral-research/