REHABILITATION OF SEVERELY RESORBED MAXILLAE WITH ZYGOMATIC IMPLANTS:
A LITERATURE REVIEW
However, anatomic measurements to assess the
position of the head of the zygomatic implant with
regard to the middle of the crest of the alveolar
ridge should be included (1, 19). The posterior
palatal position seems to create difficulties in
upholding hygiene by patients and a bulky dental
bridge sometimes can lead to discomfort and/or
speech problems.
A particular advantage of this type of implants
is the possible shortening of the treatment time
which could be achieved with immediate or early
loading . Studies that used immediate zygomatic
implant loading reported decreased treatment
times and increased acceptance of the treatment
by the patient (35, 40, 44). However, owing to the
small number of patients enrolled and the short
follow-up times, further studies are necessary to
confirm these results (24).
One of the prerequisites for immediate or
early loading is high initial implant stability
(24). The special properties of treated-surface
implants,TiUnite Nobel Biocare, may have
contributed to the favorable results of many studies
(49) . Their micropores and properties similar to
ceramics ensure a high osteoconductivity and
rapid anchoring to the newly bone formation (50).
The failure rate described in literature was not
related to the number of zygomatic implants but,
probably, to poor oral hygiene and soft tissue
contamination surrounding the abutments (1, 48).
A strict control protocol is important to observe
because the soft tissues may act as a bacterial
reservoir (38). Furthermore, Al Nawas et al.
reported that the probing pocket depth increased
even in absence of bleeding and pathological
colonization. This indicates a non-infectious cause
of the soft tissue alteration probable.
Finally, an excellent survival rate was observed
for zygomatic implants in cases of prosthetic
rehabilitation of patients with maxillary resorption
(Table 7). Many studies showed an implant survival
rate of 100% combined to similar prosthetic results
(20, 24, 42, 44, 47, 48, 51, 52).
Conclusions
In conclusion, the cumulative survival rate and
patients’ satisfaction indicate that zygomatic
implants could be an effective alternative for the
management of an atrophic maxilla and, in some
cases, be the only treatment solution.
The survival rates of these particular implants may
be related to suitable presurgical examinations
and surgical procedures, whereas their failures
reported in some studies are more related to
local infection than the number of zygomatic
implants.
Particularly, if a zygomatic rehabilitation is used a
proper skilled surgical technique is required and
regular recalls are essential to allow long term
successful results.
However, despite numerous positive zygomatic
implants outcomes, there are no well-defined
criteria that help the clinician to evaluate the
success of a rehabilitation supported by these
implants.
Thus, further studies are necessary to assess
the long-term prognosis of the zygoma implant.
Conflict of Interests
The authors declare that there is no conflict of
interests regarding the publication of this paper.
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