Ac. Meijering et al., SURVIVAL OF 3 TYPES OF VENEER RESTORATIONS IN A CLINICAL-TRIAL - A 2.5-YEAR INTERIM EVALUATION, Journal of dentistry, 26(7), 1998, pp. 563-568
Objectives: In this clinical trial, 180 veneer restorations (VRs) were
evaluated. The purpose of the study was to collect survival data and
to find possible relations between survival and (1) 'type of VR', (2)
'preparation design', (3) 'operator' and (4) the patient-related varia
bles 'tooth-type' and 'vitality of the tooth'. Methods: The restoratio
ns were provided by seven dentists in 112 patients on central and late
ral maxillary incisors. Experimental variables were: 'type of VR' (eit
her direct resin composite (DC), indirect resin composite (IC) or porc
elain (P)), 'preparation design' (with and without incisal overlap) an
d 'operator: Failures were recorded at two levels: absolute failure (n
eed for new restoration) and relative failure (need for repair). Survi
val was defined at three levels: (1) survival of original restoration
(S-r, endpoints: 'absolute' failures), (2) functional survival (S-f, e
ndpoints: 'relative' failures) and (3) overall survival (S-o, endpoint
s: both 'absolute-' and 'relative failures'). Results: The variable 't
ype of VR' showed significant influence on S-f and S-o but not on S-r.
S-f and S-o rates of P, IC and DC were, respectively: S-t-P, 94%; S-o
-P, 94%; S-f-IC, 94%; S-o-IC, 90%; S-f-DC, 80%; S-o-DC, 74%. VRs on vi
tal teeth showed a significantly better survival than VRs on non-vital
teeth at all survival levels. Conclusions: Preparation of the incisal
edge for incisal coverage is considered to be unnecessary to assure o
r improve the strength of VRs. Veneers on non-vital teeth showed highe
r risk to fail than veneers placed on vital teeth. Porcelain veneers s
howed the best overall survival. (C) 1998 Elsevier Science Ltd. All ri
ghts reserved.