الفهرس 
Challenges of endodontically treated teethOnly 14 pages are availabe for public view
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Abstract
Endocrown proved its reliability and durability and efficacy in
restoring the endodontically treated teeth due to its better stress
distribution and it is less invasion approach, more conservative as it is a
caries oriented preparation and don’t require radicular preparation in
addition to that it is time and effort saver. On the other side, the
inlay/onlay retained bridge proved its reliability and efficacy in restoring
the missing teeth with a conservative tooth preparation.
Success of the two aforementioned designs of restorations with the
care to be conservative, pushed us to make a hybrid design from the
inlay/onlay retained bridge and endocrown which is the endocrown retained
bridge and to investigate about its reliability through scanning fresh
extracted sound maxillary second molar and second maxillary premolar
with a high resolution cone beam CT in the endodontic mode to reproduce a
natural and reliable anatomy of design in order to simulate the natural teeth
form and we used Mimics 15.01 (Materialise NV) and 3-matic 7.01
(Materialise NV) softwares in the designing process of our design.
We used ANSYS Workbench 14 (ANSYS Inc., Canonsburg, PA,
USA) software to apply the masticatory forces on our design and we calculate
stresses upon our design then we tabulated results to complete our study.
We found that endocrown retained bridge was a successful design
of fixed partial dentures according to our study and it can be manufactured
from lithium disilicate, zirconia reinforced lithium silicate and zirconia
but preferably to be manufactured from zirconia reinforced lithium silicate and lithium disilicate because they presented the most favorable stresses
on teeth and less liability to teeth fracture.
Additionally, zirconia reinforced lithium silicate is a promising new
type of ceramic that proved according to our study that it can be used in three
units posterior bridge construction due to its good mechanical properties as it
is used till now in construction of a single tooth restoration only.