All-on-4
Update, Prosthetic Options, Tips and
Procedures
We are excited to
be helping more clients than ever before restore screw-retained hybrid dentures
popularized by the marketing of the All-on-4 technique. In fact, in 2013 we
fabricated more cases with this design than in the previous three years
combined. Due to the frequency and volume of this type of casework in the
laboratory we have been able to refine our technique to provide an outstanding
product at a reasonable flat-rate fee. Our All-in-One fees allow you to quote
you
r patient knowing the price will be the same regardless of implant brand (with a few exceptions) or the number of implants placed. Based upon our experience, and the input from customers, we want to share helpful information as we begin the New Year. All of us at ROE thank you for trusting us with these cases and promise to support you in every way we can to help ensure your success and the satisfaction of your patients.
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Consider the Need for Multi-unit Abutments (TMA’s)
Multi-unit,
or Transmucosal abutments (TMA’s), are permanent fixtures used for three
primary reasons. First, they bring the restorative platform of an implant from
the bone level to the tissue level which prevents ‘sluffing’ tissue around the
implant during restorative and maintenance procedures. Second, they redirect
the trajectory of the prosthetic screws to a more esthetic or functional
direction preventing access holes from emerging through undesired locations on
teeth, especially the facials. Third, they can correct angles of divergently
placed implants allowing a common path of insertion.
In our experience, multi-unit
abutments are used in 50% of edentulous, fixed cases and are utilized in two
common scenarios.
Senario 1 – The treatment plan calls for an immediate
provisional appliance. The surgeon or restoring dentist places the implants,
aligns the TMA’s to a common path-of-insertion and screw-emergence position to
accept the provisional appliance, and torques them in. The TMA’s are the final
abutments and will be used for the provisional and final appliance. In other
words, there is no need to buy additional abutments for the final restoration
in this scenario. It would be prudent to discuss with the placing doctor who will bear the cost of the parts
needed for the immediate provisional conversion. The only parts needed for the
final definitive restoration of the case are abutment-level impression copings
and analogs.
Senario 2 – Implants have been placed as a Two-Stage surgery.
The patient will present after successful osseointegration with healing
abutments in place. It is important, at this time, that careful analysis is
followed to determine the need for TMA’s and the correct angles and cuff
heights.
The need for these components
should be determined at the very beginning of the process before any final
impressions or prosthetic work is done. We suggest the following procedure as
the first step in the restoration process:
1.
Make
a duplicate of the patients existing denture. (http://roedentallab.com/downloads/duplicatetechnique.pdf)
2.
Take
an accurate alginate impression of the arch making sure that the healing
abutments are present and visible on the ridge showing the angles of the implants;
or take a reline impression inside the duplicate
denture capturing the position of the healing abutments.
3.
Provide
the deepest probing depth around each implant, or send an implant-level
impression.
4.
Send
this information to the lab. We will determine the abutment angles needed from
either one of these procedures by relating the implant position and angle to
the position of the teeth on the duplicate denture.
5.
The
appropriate parts can then be ordered and the final restorative process can
begin.
Consider the Cost of Multi-unit Abutments in your fee
The cost of TMA’s can be as
much as $345 each, and together with multi-unit impression transfers and
healing caps can be $510 per implant. Ordering parts directly or using
aftermarket parts can reduce the total. The probability of this cost should be
taken into consideration when quoting fees. It is also important to note that ROE does not include
multi-unit abutments, impression transfers, cover caps and analogs in our
All-in-One fees, since many cases do not require them and often they are
provided to us by either the restoring or placing doctor.
TMA Selection
& Confirmation Jig
During surgery
(as described in Scenario 1 above), once the implants are placed, the doctor
must decide which angle and cuff-height is appropriate for each TMA. The angle
selected and how they are placed will ensure that the screw trajectory is
aiming to the correct location on the prosthesis. One method is for ROE to
create a clear duplicate of the immediate denture with troughs cut into areas
where the screws should emerge. The abutments are tried-in with the seating
handles attached, and maneuvered until the handles protrude passively through
the troughs. This will ensure accurate selection and placement.
Avoid a Multi-unit Abutment Puzzle
When multi-unit
abutments are required it is always suggested that they are placed clinically
and an abutment-level impression is sent to the lab. With the various positions
that an angled abutment can be placed, and the very small screw size, our
clients have reported difficulty in transferring the abutments from the model
to the mouth accurately. Save yourself the challenge and consider the above
suggestions and determine the need for these parts at the very beginning of the
process.
The TLZ-IB Prettau Bridge Alternative
If you are looking to upgrade a hybrid denture or want
to offer an option other than acrylic, look into ROE’s TLZ-IB (Prettau) bridge.
This exciting, primarily monolithic zirconia design is much stronger and more
esthetic than conventional hybrids. This design comes in a unique two-step
process. First, if the patient likes their temporary hybrid, we digitally
duplicate it into an acrylic prototype that the patient ‘test-drives’ for a
week or two. When the patient gives final approval, it is returned and
converted into the final prosthesis which is truly an amazing work of dental
technology.
Implant Brand Selection – Critical
When it comes to the
restoration of both conventional hybrids and TLZ-IB’s not all implants are
created equal. Some implant systems provide better restorative options than
others. In fact, some brand selections make it very difficult to complete these
case designs. We encourage communicating with us, when possible, about the case
design prior to implant selection to ensure your objectives can be met and
excess cost is not incurred.
Thank you for taking time to
read our update. We welcome your calls on these or any other subject!
Warm regards,
The ROE Team
