Wear of Enamel Against Polished Zirconia Crowns

Inclusion Criteria

• •Subjects must be over 21 years of age and in good overall health. No contraindications to dental treatment are present
• •Subjects must be in good overall good dental health and are at a low caries risk, with no active tooth decay (caries), and no periodontal disease. Periodontal pocket depths on all remaining teeth are not greater than 4 mm
• •Subjects must have no existing temporomandibular disorder, (e.g. clicking, popping, pain on opening) or parafunctional habits (e.g. bruxism, clenching)
• •Subjects must need a crown on either a first or second premolar or first or second molar in any arch. Abutment teeth must be restorable and have a crown:root ratio of at least 1:1. Abutment teeth must have a full complement of opposing non-restored or minimally restored natural teeth. Minimally restored means the teeth contain no restoration greater than a Class II amalgam restoration. The opposing arch must not have a full coverage restoration or a partial denture. The contralateral tooth and its antagonist are present
• •Subjects must exhibit good oral hygiene and compliance with oral hygiene instructions as determined by the amount of plaque present on tooth surfaces
• •Subjects must exhibit a normal flow of saliva. Subjects with any medical pathologies that limit salivary flow volume or who require a chronic intake of medications that minimize flow of saliva will be excluded from the study
• •Subjects must be willing to pay $500 for the clinic incidentals and they must be compliant with yearly appointments