Danny, The dia. of the tip is not the same as the area of the tissue removed. Some Er lasers can be used in contact . I would assume the area of the tissue remove would be close to the same. Many lasers are used in what we call focus. That is held 1-2mm form the target tissue. There is some divergence of the laser energy. If you use the laser out of focus the area of affected is even greater. You cannot think of the area of tiisue removal being 0.4mm.

Case 1.
The case that I showed also had an exostosis present. After I did the case it became apparent to me that the presence of an exostosis in the area to be crown lengthened is a contraindication for closed crownlengthing. I just find it hard to move the tip in such a way to remove such a large amount of bone.
In hide sight I did not need to flap this case to prove it to myself. If when I had done my closed procedure and was checking to make sure I had enough depth of reduction, I had moved my periodontal probe lateraly I would have felt the trough that was created.

Case 2
This case could be done closed. I think that if you visualize what is present and then work the laser defoucsed coming down the axis of the tooth and then flaring out. Then going back with scalers to remove the thin ledge of bone next to the tooth. The interproxal areas will be a bit tough but still doable.

Case 3
Now this case is an easy closed laser case. I can not tell form the slides but the interproxaml areas appear to need little reduction. The fact that the osseous is not thick and there is already a ledge present is helpful. By sounding and looking at the tissue you should be able to tell if the osseous is thick and by sounding with the probe the ledge can be found. By working the laser tip from the ledge out it should be easy to taper the the bone.

Case 4

Furcations and closed procedures are contraindicated. I have never heard of someone trying to do CL close with a furcation being present.
Looking at this case I feel that it could be done with a laser as an opened case. The enamel projection would be easy and the osseous not much of a problem. The root reshaping is like doing a crown prep. I would still have to use the diamonds to smoothness of the root as you have . I wonder if Mark can get it smooth enough. His crown margins are pretty smooth.

Danny this is probably not what you wanted to hear .

David

I feel that Dr. Melker’s reflected flap photos provide evidence that in the majority of cases, closed crown lengthening procedures are contraindicated. The photos demonstrate to me that without reflecting a flap, bone is thicker facio-lingually than we think. Look at buccal of #3 in Case 1, labial of #7 in Case 2, buccal of #3,4 and 5 in Case 3. In Case 4 hard to tell as flap is not fully reflected.

With the closed procedure, we simply can’t visualize osseous structures for proper facio-lingual reduction, blend the osteoplasty to adjacent teeth and smooth out the bone. We are going to wind up with a “trough” and rough bone if we attempt to use the erbium in a closed procedure. Today’s periodontists can conservatively execute an open-flap procedure even on single teeth without causing major recession on adjacent teeth.

In my opinion, the use and marketing of erbium lasers for closed periodontal crown lengthening procedures should be reduced. But I’m not saying we shouldn’t use it for crown lengthening. The erbium laser is an excellent tool for osseous reduction/contouring in open flap periodontal procedures.

Al

Danny bone remodels. Lets say I am able to not trough but I leave a ledge on the facial . Won’t this remodel and round off. I still remember doing a deep DO alloy in school and getting down to bone. I called the instructor over and ask what to do. Band it wedge it and fill it. The bone will remodel and receed from the alloy. If we leave
a trough at the line angles that won’t it remodel and round off?

David

I never count on remodelling around teeth to fix what I didn’t get to, and I never count on bone dieback on an implant to adress something I missed.

I don’t count on remodelling or things like dieback because they aren’t things that are predictable case to case.

In regard to that alloy-it was iatrogenic periodontal disease long term…though it may have been mild. In that case, it remodels in a way that may or may not be favorable with health. You will have a long term, bleeding area of tissue depending on how close you got to bone.

Danny is touching on many of the things I talked about close to a year ago at DT when this subject came up.

I love these discussions on this topic. Any rebuttals?

“Almost all related to some moron placing a margin in violation of the biologic width and thinking he can challenge the patient’s biology and win.”

Bill your lucky that you have Danny to work with. In general when I see BLW invasion it is not because the dentist who did it was a moron. You see things differently then most because of what you have been exposed to. I think that one of the major reasons that we have BLW invasion with crown and bridge is loss of orientation. That is we try to tuck the margins of our crowns within the sulcus ( another issue). It becomes real easy to loose your sense of depth and get too deep. Another way is to not come up through the interprox areas, that is to come straight through. Still another is the poor dx. That is not knowing the caries/old restoration is already in the BLW and you are preping the patient when you discover there is a problem. We still have many that are not aware of BLW. I have had a few local guys that I have sent patients back to because they have violate the BLW and I have to explain it to them. This goes back to my clinical instructor. He was wrong. More importantly the school was wrong. Not enough importance was given to the perio. dept (or Occlusion) . The other factor is what CE do you see out there for the general dentist that is related to perio/pros ? Little to none. Another big factor is cost . At times it is all a patient can do to have one crown done. Then add the cost of CL. Often there is a RCT to be done. Now one tooth needs RCT ,Core,temp,and a crown. In my area that is often more then the patient can afford. As one dentist told me doing CL sx is a deal breaker. The patient either goes some place else ,does nothing or has the tooth extracted. This is one reason closed crown lengthing with a laser is so applealing to GPS. It over comes the issue of having to refer a patient out ( pts do prefer to have everything done in one office) and it keeps the cost down. It keeps the cost down because there is fewer appts,no extra temp and GPs generally charge less for the CL sx.

Post op cases . You bring up a great point. There are not many follow up cases posted. Part of it is most of us have not been using lasers that long. The other is time. Time to post the case. It does take a while to post cases. (Ask Danny). Then remembering to take the post op pictures when the patient returns for recall. Something to work on.

Bill this is a different forum then over at DT. DT is like a pub that often gets out of control. We play nice over here. It is more about helping each other ,learning and not bashing.
Welcome.
David

Glenn and David,

Thanks for your posts. I too am here to learn and if my loose language bothers you I apologize. I am however very opinionated about teachers in dental school and dentists who are too lazy or sorry to learn about what they are doing to people. It is simply wrong to violate the biologic width with restorative materials, it is wrong to leave decay, it is wrong to destroy biology for the sake of profit and it is wrong to not say something about those that do.

If this group is a closed group that seeks to avoid conflicts, desires unified positions and eschews strong opinions about right and wrong then I will be inclined to rock the boat here.

I am interested in the technology from the perspective of teaching crown and bridge. Many of the cases presented here stop on the day of surgery. If someone can post even a one year post op photo of a case it would be helpful for me to decide for myself if there is merit to the technology. Without post op photos I can not make sense of what is being claimed.

I must admit that I am skeptical about the ability of technology alone to  conquer ignorance of surgical/biological parameters in the hands of surgically untrained dentists but I am anxious to see some results.

Didn’t mean to get you upset from the very first post.

(Edited by billstrupp at 6:21 pm on June 13, 2004)