When restoring an endodontically treated tooth, what characteristics make
the restoration ideal?
-
Strong, supportive and functional
-
Excellent fit
-
Easy to prep and seat
-
Beautiful
The Bernstein VIP restoration (Vectris Integrated Post) provides an excellent
solution in those cases where the ideal treatment would be a custom post
and core under a full coverage crown.
Problems with previous post-core/crowns included:
- Difficulty in retrieving metal or ceramic posts (if required)
- Metal
shows through
- Weak adhesion to metal
- Metal is less flexible than dentin leading to
root fractures
- Compromised esthetics
- Extra steps with 2 piece post-core/crown techniques
The VIP restoration solves these problems using a single unit Vectris integrated
post (VIP) with Empress. Similar to an LVI bridge, the Vectris fibers are
packed into the Empress in the lab to create a very strong and beautiful
restoration that is easy to bond. By making the post and crown as a single
unit, the lab can verify an extremely accurate fit on the model.
Preparation is simply a standard custom post prep with a chamfer or rounded
shoulder on a 3mm ferrule. The gutta percha should be capped with glass ionomer
or composite resin during the preparation of the canal. In making impressions,
it is helpful to blow the impression material down into the canal with an
air syringe. It is also helpful to coat the canal with Tempbond Clear (Kerr)
when fabricating the provisional to facilitate removal of the Bis-Acryl provisional
material from the canal at delivery. Bonding the final restoration is
easily accomplished with auto curing luting materials preferred by the clinician
using standard bonding techniques.
The Bernstein VIP restoration satisfies the requirements of outstanding
clinicians who wish to easily provide excellent restorations for endodontically
treated teeth with minimal clinical crowns.
The laboratory techniques should be done under a 20x microscope with multiple
solid models and virgin dies to ensure accuracy of the VIP system. Models
should be properly equilibrated as well to allow for minimal occlusal adjustments.
The post is fabricated in 2 steps after the Empress is fabricated in the
conventional manner. As well as being easier to deliver clinically, the system
is homogenous in strength after processing. The processing takes place internal
to an etched and silinated Empress crown.
Standard verification techniques are used to ensure minimal occlusal adjustments
(properly equilibrated models to simulate a power clench) and on multiple
pours of original impression for both solid models and virgin dies with the
goal of no bite adjustments at chairside.
- Wax post and prep space
- Wax full contoured Empress restoration and press
conventionally .
- Duplicate wax-up of post and prep inside empress crown
- Make Siltec putty
stent of post and Empress and remove wax pattern leaving the pattern
and empress intact
- Press pack Vectris fibers into remaining space and process
to etched and silinated Empress restoration in Vectris VS1 machine
- Remove
remaining vectris from apex of prep and fit to verification die, solid
model and working model and die. One of the most important steps in this
process is to be certain that the post and crown assembly fits exactly
under a 20x microscope on the untouched virgin die.
The strength gained from processing the vectris to the Empress in the Vectris
VS1 machine is higher than would be obtainable intraorally without the uncertainty
of whether the post and crown will fit the tooth .
This technique is new and somewhat time consuming but shows excellent promise.
Josh Bernstein, DDS, is a Clinical Instructor at LVI. He maintains a private
practice in Piedmont, California, focusing on restorative cosmetic dentistry,
smile design and outstanding guest services. Bob Clark, CDT, is co-owner of
Williams Dental Laboratory located in Gilroy CA. Williams Dental Lab is a full
service, LVI-trained Aesthetics NM laboratory, providing their clients with
all that is taught at LVI.
