FULL-MOUTH ZIRCONIA-BASED IMPLANT-SUPPORTED FIXED DENTAL PROSTHESES.
FIVE YEAR - RESULTS OF A CLINICAL PILOT STUDY.
Figure 1. Patient M.A. (female, 68 y). Intraoral
photograph before surgery, frontal view
a
Figure 2. Patient M.A.
Immediately post-surgery X-ray
b
Figure 3 a, b. Patient M.A.
Frontal and lateral smile with the final prostheses
the CAD-CAM manufacturing dental technique.
Nonetheless, some problems are still unsolved. In
particular, technical complications like framework
fracture and veneering porcelain chipping (3,4)
also in case of implant-supported zirconia-based
fixed dental restorations (5,6). Different methods
have been suggested to solve the problem of
chipping veneering porcelain. In brief they could
be summarized as follows:
- use of anatomically contoured framework
design with respect to the veneering ceramic
thickness necessity (between 1.5 to 2 mm) (7);
- slow heating and cooling regimes when
porcelain is fired on zirconia (8);
- the press-over veneering material technique
(9);
- the sintering technique where CAD-CAM
lithium disilicate veneer is linked to a zirconia
framework (10).
The clinical necessity to collect data in order to
understand, control and avoid the high percentage
of chipping (40%) that occur in full-mouth implantsupported zirconia-based fixed dental prostheses
(FMIZBRs) (11) is the objective of this clinical trial.
In this paper we provide the 5-year results of a
pilot study on FMIZBRs.
STOMA.EDUJ (2014) 1 (2)
Figure 4. Patient M.A. Chipping
complication at the two-years recall
visit. The chipped surface was
polished with patient’s satisfaction
MATERIALS AND METHODS
Patient selection
Between March and July 2014 five women aged
55-75 years were selected from dental hygiene
clinical recall appointments in a private Milan
dental clinic. They all had received FMIZBRs from
the same private practice between January 2008
and January 2009. Inclusion criteria were good
general health without severe general and local
medical or psychological conditions (as reported
by the patients), and edentulous maxillary and
mandibular dental arches for at least three months
(Fig. 1).
All subjects provided informed consent for
the clinical procedures, in accordance with the
Helsinki declaration and the Italian law. Five years
extended warranty for the restorations was offered
in case of failure. All subjects had confirmed their
informed consent already provided to the clinical
procedures in conformity with current guidelines
for good clinical practice (12).
An independent operator, who did not
participate in the original prosthetic procedures,
performed all evaluations.
The survival rate was defined as surviving fixed
dental prostheses minus altered fixed dental
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