Clinical fractures of veneered zirconia single crowns.

Crowns made from an yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP) core with a porcelain veneer have shown high clinical failure rates. Manifestations of clinical failure in veneering ceramic ranges from a single chip to an extended fracture. Core failures are uncommon but usually are catastrophic.

White enamel lesions and their progression from childhood to adolescence: a prospective study.

Purpose: To assess the current situation of white enamel lesions on vestibular surfaces of permanent maxillary incisors, diagnosed 6 years ago, without clinical intervention.

Materials And Methods: The prospective study reassessed 53 students of both sexes, aged between 13 and 18 years old, all attending the public school system in Natal, Brazil. Data collection was performed by calibrated examiners, and a clinical chart consisting of demographic data on dental caries, oral hygiene and gingival condition was prepared.