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Buried polished collar

From: Terry Pannkuk
To: ankylos@rxdentistry.com
Sent: Wednesday, May 12, 2010 12:35 PM
Subject: Today's buried polished collar.

Here’s a Nobel BioCare Replace Select Straight that I buried flush to the osseous crest today
(polished collar and all ).  I think these are popular because they are easy to restore and most
general dentists have the kits for NBC.  They like what they are used to.   There is certainly
nothing wrong with NBC and it is what I’m asked to place 80% of the time.so I do it.- Terry





Ahhh...savor that pre prosthetic x-ray.  Things will never look better
with NBC! But, it is very easy to restore :-) - Arturo

So is this artistic rendition of what to expect that bad or that far off?  The adjacent teeth will hold up
the tissue and bone.   The bigger question is how much of a compromise it is to lose 3mm of bone down the
polished collar and lose very little tissue?  I’ve found the NBC to be extremely stable and if a referring
dentist is comfortable restoring them, they are less likely to have future problems.

Presuming Ankylos would hold the bone up to the platform a decade later.  How unstable and much worse is
the NBC compromise?   Will the bone drop down on the adjacent natural teeth?   Will the bone migrate down
beyond the first thread?   Is peri-implantitis risk greater?

From what I’ve seen on single replacement implants between two natural healthy teeth, the bone isn’t
expected to go away is it?   I like the idea of platform switching and the fact that bone/tissue is held up,
but how big is the problem that is being solved by Ankylos in a nonesthetic site like this?

Again,  I don’t use NBC in esthetic sites. -  Terry



Three questions.

1.  You placed a polished collar flush with the osseous crest, even though that implant is indicated for
    supracrestal placement as the soft tissue prefers the polished Ti and the hard tissues prefer rough Ti.
    Where will the bone end up in 2 years?

2.  What is the middle radiograph on the second page demonstrating?  The paralleling pin is in the air.

3.  The final photo makes the implant look like it is buccally placed.  Good mesial/distal positioning.
    But remember it is all about 3D placement.  or is it the angulation of the photograph? - Dwayne

Dwayne,

1.  I was taught to place these implants flush.   Supracrestal would mean a tomato on a stick  no emergence
    profile and a food trap.  Bone should migrate to the first thread and stay there (I hope); I expect the
    tissue to hold up and the restoration to have natural emergence.  Who places these implants supracrestal?
    their restorative dentists must hate them!   When I consider the Ankylos design versus a traditional
    parallel design, I keep asking myself which is more of a problem?....a horizontal food trap or a vertical
    one?  I don’t really know but how easy is it for patients to clean the narrow neck?

2.  The guide pin is a in my surgical guide which is radiolucent and shows the angulation of the pin as a
    check before drilling the osteotomy.

3.  It is slightly toward the buccal, hopefully catching some native bone on the buccal.   An oral surgeon
    in Israel had performed the extractions and grafted the sockets with mystery foo foo a couple years ago.
    I don’t know what the darker material is filling the socket; it didn’t’ penetrate with the needle during
    the injection, but I liked the idea of hugging the buccal and getting some contact with some of the dense
    buccal native bone.  The mandibular nerve canal was also toward the lingual at 15mm depth.
    I placed a 11.5 x 5.0.   The slight buccal placement was intentional, here’s the cross-sectional CT’s:

- Terry



Terry

Since we are all citing biology as our reasons for doing what we do there are some biological principles
we should all be aware of

- Bone does not like smooth Titanium.  Fibroblasts and bone prefer rough Ti.  Gingival connective tissue prefers
  the smooth Ti.  This implant is specifically fabricated and its suggested usage is that the polished portion
  to be placed above the crest.  If your submergence and emergence profile predilection/criteria does not fit
  this specific design then you are using the wrong implant.  Might i suggest the NRS with TiUnite to the
  shoulder- "NRS Groovy".  Know your systems and what they are designed for.

- We are all taught to do certain things, but must change and adapt with the times/technology.  "I never let
  schooling interfere with my education"  Mark Twain

- This is not a discussion of Ankylos vs NRS...but rather is NRS is your choosen system then use the bullets
  that go into your six shooter accurately and judiciously.

- Why check angulation of the pin prior to initiating the osteotomy.  So many variables can enter the equation
  after that in my opinion it is a moot point.  And subjects the patient to unecessary radiation.  Again,
  my personal opinion.  A much better radiograph if you are so inclined is either half way through the initial
  osteotomy with the 2mm pilot drill or once this initial osteotomy is completed.

- If you are so concerned about the submergence/emergence profile of the restoration the certainly purposefully
  engaging the buccal plate of bone with the NRS WP will cause the resulting abutment and crown to have too
  prominent a buccal contour.  OVER contour of a restoration has terrible biological consequences.  It would be
  much more prudent to center the osteotomy on the central grooves (assuming they are in ideal relationship) of
  the adjacent teeth.  This was the implant is centered and the resulting crowns profile will be ideal...
  The current thought with implants (especially in the anterior) is to avoid the buccal plate of bone.
  I know this is not an anterior case, but i follow the principle through.

- If you had measured on a CBCT the distance to the Mand nerve was 15mm and you are not countersinking the implant
  and presuming you want maximal bone/implant contact why not place a 13mm implant...what is your rationale for
  a 11.5mm implant?  The CBCT that you show...what stage of the procedure is that? - Dwayne

On May 12, 2010, at 9:24 AM, Terry Pannkuk wrote:

1. How much radiation do you think a digital radiograph exposes a patient to?  I like to validate the buccolingual
   position using the stent in the mouth before drilling and figure the patient won’t get lymphoma from that event.
   I take several radiographs along the way to check for drill shifting in soft bone.   Radiation exposure is a
   non-issue as far as I’m concerned but I only take radiographs I think that will help me.

2. Fibroblasts may not like smooth titanium but neither does plaque/bacteria biofilm which love rough surfaces
   having pores ideal for colonization.

3. How far buccal off center do you think I placed this?  The patient had excellent ridge width and there is well
   over 1mm of dense buccal plate covering the buccal portion of the implant.  I know you wouldn’t want me to take
   a scan (exposing the patient to more radiation) of the case post op but I don’t mind when the patient comes in
   for a check visit next week figuring it would be good validation of my placement. J

4. Do you really think a  11.5 mm deep implant in mandibular bone with excellent primary stability has any negative
   significance compared to a 13mm deep one?   I personally like 3mm safety space from vital structures if possible.
   A 13 mm brings me potentially within 2mm and if there is any CBCT distortion which does occur, it could be problematic.

You are clearly more concerned with things like radiation exposure, length of implant, junctional epithelial attachment
on smooth surface titanium, and other issues which I am not.

I’m concerned about the mystery foo foo, vital structure proximity, and not creating a conflict with the restorative
follow-up (i.e. being compatible and on board with the restorative dentist’s plan to the extent it doesn’t compromise
the case.   I just haven’t seen your concerns that you are raising being a problem with the clinical results I’ve had.

I’m open to the possibility that maybe I should be concerned with the things you are saying, but I just haven’t seen
any evidence of it being necessary yet.-  Terry

When the bone does not attach to the smooth Ti ( and resorbs as it will).. this give more surface area for the biofilm
to adhere to...including the abutment.

All radiogaphic exposure is additive.  Thus anything which is redundant is unecessary (opinion).  Do you take
radiographs of your Endo files before you enter the pulp chamber?

To my knowledge there is no distortion (or if any it is minimal) in a CBCT.  that is why we can accurately measure tenths
of millimeters.  However, i will confirm this with a Oral-Maxillo Facial Radiologist at UTHSCSA.  Certainly not enough
distortion for concern regarding 2mm.  Why do you not then do a CBCT with a measuring gauge,  say a 5mm ball bearing,
like we used to do with Pans.

Buccal bone is sacred...the sanctum sanctorum so to speak...always stay 2mm away.  if your philosophy was to engage this
for greater stability, then i think you should go longer with your implant, and have more centrally placed.  again
assuming you are desiring more stability and bone/implant interface.

If the mystery foo foo is of concern then call or email the doc in Israel....I have delt with docs in Israel, Russia,
Hong Kong, Taiwan, Brazil, Iran and Phillipines...and others.  The internet is a powerful tool if you choose to use it.
If  you cannot get an answer then perhaps you should remove it as you do not know its biologic consequence.
What if it is Bioplant (acrylic beads with HA coating...god forbid) used the socket.    What would you do if a patient
presented to you with Sargenti Paste or Silver points????  If you do not know then it is wrong to place an implant into it.
Remove it,  regraft and place the implant at a later date.  This is the biologically sound thought process.- Dwayne

Good point on the mystery foo foo and removal consideration. It may have been a bit blind faithish to place an implant
into the unknown.   The bone that came out during drilling looked pretty normal, no Bioplant, so the main concern was just
that it wasn’t native bone.   BMP is the only real good stuff that becomes real bone.   The buccal plate is solid as a rock.
I suppose you aren’t going to be satisfied until I get a CBCT from this guy and measure the remaining buccal width.
I’ll do it when he comes in.  I have well over a mm,  maybe didn’t even engage it, we’ll see with the CBCT.

I didn’t need greater stability,  I had to unwind, wind a few time to lessen the torque!

I did take radiographs during the process:-  Terry




If I hear constantly the story about comprehensive treatment planning Terry.....how do you rate the progress of the
crown and its margins distal to the implant. Do you anticipate another implant crown needed in 1 year.
The margins again look suspicious - Glenn

So you’re presuming it isn’t recorded and on the bucket list of prioritized items to be treated?
You presume that I dictate the sequence of executed treatment options to the general dentist; i.e. quarterback?
Yep, you’re right it’s a crap crown requiring replacement.  So?  - Terry

Dwayne:  If I am correct you have a dual degree in Periodontics and Prosthodontics.  Am I correct in this.

If so , I would imagine that you spent a vast amount of time in your education in the USA ( was it Columbia university)
learning about implants and the issues you relate here to us.

Its amazing that anyone would not sit and think a long time before defending their opinions in my mind unless they have a
similar degree of training.

I guess some people just love to argue about everything and never take the time to sit quietly and take advice from someone
else or constructive criticism on their concepts.

I for one have learned A LOT from your comments.  Please continue to educate us as your background in this topic is beyond
reproach.  I am sure that others could learn as well some from your vast knowledge. Thanks for sharing.- Glenn

Glenn, I am sure that this opinion is a bit contaminated with your previous discussion with Terry on Roots.
Not disrespecting Dwayne, but one is not measured by its degrees and titles.  You are an example of this since you are a GP
and teaches all over the world about different topics with a great expertise.

Terry has the write to disagree about this topic or any other, and he has a knowledge basis to do that even do he is not an
specialist.  We leave in a democracy and a forum like this should be a place for education not for its killing.

I strongly believe that if Dwayne presents some solid literature all of us will learn and progress, in the contrary if one
can not "challenge"  the current status quo of or a "big" shot all of us will leave as prisoners of imaginary boundaries.

I learned a great deal from you and many others with out of a formal degree.  Just let the past goes and lets focus in the
future. - Dr. Carlos Murgel


Carlos, yes terry had the right to diagree.  however, his arguement was not supported by the lit.  merely opinion.
what i have stated is supported.  it has been my mistake not to give references, however, in a busy implant practice
i do not have time to look them up.  where i am not an authority in a subject i have outsourced my material.  i am still
awaiting a response to Terrys comment about distortion in CBCT (he is wrong BTW)...this rebuttal is coming from the
department head of OMFR at University of Texas San Antonio...i am told i will have it later today.  but everyone is busy
and sometimes in blogs you cannot reference properly. i do not know how Ken does it.

catch my presentation in Barcelona, everything will be referenced.. - Dwayne

Carlos:  A very well written and thoughtful post.  I have learned more from people on ROOTS about endo over the years
than anywhere else.
If I do lecture and provide any information it is basically on two topics-

1. Lasers
2. Microscopes

I do have 13 years of clinical experience and 3 DVDs in the microscope field.
I have a mastership in lasers.
I guess that allows me to present some useful information on both topics.
I also know my place and that is that I am not an endodontist or an implantologist.  I realize that I am in no position
to argue with "expert" or those who have gained a foundational background in these topics like you have in grad school.

I have no problem at all with formal , professional debate. I see no reason why personal shots must be levelled at
someone with a different viewpoint.  That has no basis in personal communication be it online or face to face.
We can maturely agree to disagree.

So when these issues keep cropping up and never are started by me , well then it is disappointing to me to see.

I am beyond it and looking forward . I too will see you in Barcelona and looking at the speaker list , I am absolutely
honored to be invited. All the best - Glenn van As

Terry this is exactly my experience with extractions: why we need to place something inside the socket if we have bone
there? - Carlos Murgel