Objective To investigate variations in preparations for procelain lami
nate veneers (PLVs) in general dental practice. Design Laboratory-base
d retrospective analysis of dies for PLVs. Setting General dental prac
tice in England and Wales (1994). Methods A sample (95 cases) of labor
atory models from general dental practice featuring preparations for P
LVs was randomly selected from a full service commercial dental labora
tory. Aspects of the preparations were quantified and compared with ac
cepted preparation criteria distilled from a review of the literature.
Results The teeth found to be most frequently prepared for PLVs were
maxillary incisors (48%). The majority of cases investigated were for
one veneer only (56%). The margins of the preparations were variably p
ositioned with more than half of the preparations (55%) having no clea
r margin. In accordance with current guidelines the incisal edge tende
d to have been reduced during preparation (47%). In contrast, most tee
th were underprepared with an average depth of preparation of 0.16 mm
(SD 0.60 mm, 95% CI-0.1, 0.42). Conclusions There was little evidence
that established guidelines for the preparation of teeth for PLVs had
been applied in full.