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Dr Gregg:
Below is my answer to your question which seems to be puzzling you and I presume everybody else reading the threads.
Your question:
“Ray,
There you go again…………”It’s one of those statements that makes you question……”
What other statements cause you to question my credibility, Ray?”You seemed genuinely puzzled. However, I believe I subtly discussed this scientific/marketing issue with you on dental town soon after we met to discussed lasers a year ago.
Since you have now decided to attack my motives and biases on a personal level, the readers of the forum deserves a hearing of why I question of your criticisms of competitor(s), whether scientific or marketing based criticism. As I have made clear before, my motive is simple, to make money. There is a public interest aspect in that I would love to see more wide spread use of lasers in dentistry because I believe the result will be better dental health for my family and the public. I do consider public interest as I refuse to invest in tobacco companies for example.
Approximately one year ago, you gave me a face-to-face presentation about your laser system and your laser business. You also gave me a venture-capital investor packet which included slides and papers from your presentation and marketing brochures. Not being a dentist and not well researched in soft tissue procedures, I understood some of the slides with your explanations and did not understand many. I believe the point that you were trying to get across to me and other potential investors before and after me was that your system offers a major improvement in clinical results compared to conventional methods with a very important clinical benefit which is the regeneration of bone and attachment. In your presentation you placed particular emphasis on bone re-growth and showed many x-rays illustrating your point. Because of my low level of understanding when it comes to interpreting dental x-rays, you emphasized your point by showing an easy to understand slide that you made by “subtraction” x-ray showing 3D bone regeneration around a treated tooth. Your presentation is encompass the results featured in your Dentistry Today article which you have on your web site. I was impressed by your dedication to the profession and your pursuit of providing state-of-the-art dentistry to the soft tissue market. The link to your article is here:
http://www.millenniumdental.com/research/may-02.html
My impression from the meeting and packet that you provided is that your Dentistry Today article is a principal piece of the clinical science behind your marketing. However, you have a glaring scientific fly in your ointment that bothers me to this day, and I subtly raised my concerns with you on Dental Town a week or so after we met and I reviewed your materials. You acknowledged in a Dental Town reply that there were software problems with the subtraction x-ray program but essentially stuck to your claims that the subtraction results were useful for showing bone growth in 3D. I will admit that my attitude a year ago of “let sleeping dog lie” has morphed into anger over time with each of your verbose criticisms of competitor(s) for not being scientific about their marketing claims. Your Figure 4 subtraction x-ray results are invalid, wrong, fiction, or as Dr. Bornstein may put it ____hit. Here is what a real subtraction x-ray looks like:
http://www.alphatecltd.com/dentistry/radiography.html (see Figure 2)
Furthermore, it is not scientifically possible to extract meaningful 3D interpretations from subtracting two 2D x-rays from the same angle as you had claimed in your presentation to me and apparently to others. All it would show are differences in density from that angle.
As potential VC investors, this raises some troubling questions for us:
1.He was not aware of the problem and will retract results and publish errata explaining error. (the best outcome and the outcome I was hoping for)
2.He was aware of the problem and did not realize the magnitude of the error. He will retract results and publish errata explaining error upon realizing error is significant. (still OK but not as good as 1.)
3.He was aware of the problem and publishes those results anyway.
4.number 3 plus he uses it embellish presentations to interested parties.It occurred to me in time that number 4 happened in this case. I am not happy about that and I wish that I had reached some other conclusion. It’s Ok to criticize others out of genuine concerns or if you have hard data contrary to claims. In the case of your posts attacking Biolase, it is very hard for me to distinguish what is genuine and what is not genuine. My minimal conclusion is that your scientific opinions are to be taken with a large grain of salt. Again, I admit that my attitude a year ago of “let sleeping dog lie” has morphed into anger over time with each of your verbose criticisms of others for not being scientific about their marketing claims.
Below I have attached my original draft (posted to Dental Town last year) to you cautioning you about your subtraction X-ray results:
>>>>>>>>>>>>>>>>>>>>>>&g
t;>>>>>>>>>
Bob and Lasersmiledr –Bob – thanks for the THICK packet of papers, you expect me to read them right? Anyway, goes great with cabernet and the world series and not necessarily in that order. Please provide a Tom Clancy novel next time so I can stay awake for the game.
I believe lasersmiledr is referring to Bob’s “Laser Periodontal Therapy for Bone Regeneration” paper and accompanying slides and figures presented in the May 02 Dentistry Today. Figure 4 is where you show the subtraction radiograph (difference between x-ray images shown in figures 2 and 3). Link to Bob’s report <a href="http://www.millenniumdental.com/research/may-02.html
Something” target=”_blank”>http://www.millenniumdental.com/research/may-02.html
Something bothered me about that slide when I first saw it and I reviewed it again just now since Lasersmiledr’s posts piqued my intellectual curiosity about Figure 4. (Must be my past experience at looking time lapsed CT’s and time lapsed differences haunting me.) In a time lapsed difference x-ray image, differences in portions of the system that have not been altered (in this case teeth, crown etc…) should cancel out to the residual (noise) level. The real significant differences will stand out as either a negative signal or positive signal depending on changes in density (bone in this case).
Here is an example from dentistry (GE medical site has examples for body). See bottom figures. Bottom right is the difference image. http://www.alphatecltd.com/dentistry/radiography.html As you can see, the unchanged portion of the teeth structure is essentially grey which represents noise and the differences (increases in bone density) where significant stands out. In Bob’s figure 4, there are differences everywhere including where things were not supposed to have changed. There must have been some mix up in the way the image was retrieved or process. My speculation is that Figure 4 is the difference of Figure 3 and a slightly rotated (or offset) Figure 3, (thus the creation of shadows and preservation of texture). In any event, it looks like the input data, the algorithm, the processing and subtraction radiograph needs to be rechecked and re-computed.
BTW — Bob you better hire lasersmiledr for VP of PR before your competitors do.
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t;>>>>>>>Dear Ray,
I’m sorry your anger has gotten the better of you.
But I understand your reasons for being angry.:angry: And it’s clearly not about my “credibility” regarding the HKS website animation anymore.:oWhen I got angry with you after you first public disparagement of me, I first called you out of courtesy to discuss it with you and I resisted the impulse to go off on you in public. I even made a post in an attempt to “take the conversation in another direction”. Yet, you have never afforded me the same courtesies when you got angry with me and came after me a second, then a third, then a fourth time in public postings.:confused:
I called you originally because I was impressed with your scientific inquiry in the subject of laser dentistry.:cheesy: You appeared to want to know the truth about the industry, the technology, the clinical utility and practicality of lasers. I invited you to MDT offices to meet with me–full leg cast and all–to share with you some perspectives from a veteran of this industry, and gain some insights to your interest in the field. I was hoping you were an investor who might be different from the others I have dealt with in years gone by, and have an interest beyond greed alone. I was hoping you might want to help make a difference, while making some money. Unfortunately, I was mistaken.:(
You subsequently challenged (and become angry) over one digitally compared radiograph and found it not to your liking. You then assign all sorts of possibilities except the explanation I gave you. I honestly think it is an inability to trust other people’s representations that leads you to suspect those who are trustworthy, yet invest (quite literally) in those people and things that IF they are true (but are yet unproven)–it would be wonderous. But I digress……..
I have acknowledged that there have been reported problems with this software (from the researchers), that I did not do this “comparison”, and felt it still represented the 3-D bone density increases we are trying to get doctors to appreciate, and is consistent with the results and images that you do not object to. Other comparative radiographs we have published show similar density profiles, and percent bone density increases, if not in the “grey scale” format of the x-ray you dislike. So where’s the real “beef”, Ray?
In any event, Dentistry Today is only a small part of the evidence we present to scientifically support our work.
Here’s some peer reviewed science that we sponsored, which I have posted and you have not objected to:
1. Peer Reviewed, retrospective, blinded, multi-centered, private practice clinical study
http://spie.org/scripts/abstract.pl?bibcode=2002SPIE%2e4610%2e%2e%2e49H&page=1&qs=spie
Study of 65 patients and over 1900 probing sites showed that laser periodontal therapy using a specific modality called “LANAP” for “Laser Ablation New Attachment Procedure” was reproducible in reducing 90% of pockets without any recession in ONE treatment by a minimum of 50% regardless of pocket depth as such:
> 4mm – 2.2mm reduction
> 6mm – 3.1mm reduction
> 8mm – 4.5mm reductionRecently published university research with human histology shows we are getting regeneration following our LPT protocol with the PerioLase–just like we demonstrate in those digital x-rays.
I have known about these histology results long before I ever posted on Dental Town or this Forum was operational……..
Published abstract from the 2003 IADR meeting in Sweeden this June.
Results from a Controlled, Prospective, Blinded, Human Histologcal en blocin an indepndent university study demonstrating that using proper technique, proper “light dosemitry” with a pulsed Nd:YAG can be associated with new attachent (new bone, new cemetum, new functional periodontal ligament in periodontal disease in humans.
This study helps to validate the safe and effective clinical use that pulsed Nd:YAG clinicians have been claiming for use in the periodontal pocket for over 13 years, where no damage to root surface or pulp has been observed.
1735 Laser-assisted Periodontal Regeneration in Humans
R.A. YUKNA, G.H. EVANS, S. VASTARDIS, and R.F. CARR, Louisiana State University, New Orlreans, USA
Objective: The Laser Assisted New Attachment Procedure (LANAP) has been advocated for the sulcular debridement of periodontal pockets with the goal of obtaining new attachment. Clinical case reports have reported favorable clinical results, but there is no human histologic proof of regeneration.
Methods: 3 patients with 2 single-rooted teeth with moderate-advanced chronic periodontitis associated with subgingival calculus deposits were enrolled. Occlusal adjustment and direct bond extracoronal splinting was performed. Under local anesthesia, a 1/4 round bur notch was placed at the apical extent of calculus as carefully as possible. One of each pair of teeth received Nd:YAG laser treatment of the inner pocket wall to remove the pocket epithelium (laser settings were 3 watts, 150 pulses/second, 10 hz). Both teeth were then aggressively scaled/root planed with an ultrasonic scaler. The pocket of the test tooth was lased again to coagulate any blood present and to form a pocket seal. Triple antibiotic ointment and a light cured dressing was placed. Control teeth received all of the above except the laser treatment. The patients were seen every 10 days for the first month, then at 2 and 3 months, at which time the treated teeth were removed en bloc for histologic processing. Decalcified step serial sections were stained with H & E.
Results: 2 of the 3 LANAP treated specimens showed new cementum, new bone, and new periodontal ligament in and coronal to the notch. The control teeth had a long junctional epithelium with no evidence of regeneration. There was no evidence of any adverse pulpal or tooth surface changes in either specimen.
Conclusions: This report supports the proof of principle that LANAP can be associated with periodontal regeneration on a diseased root surface in humans.
Supported by Millennium Dental Technologies and the Louisiana Periodontics Support Fund.
Seq #178 – Therapeutic Intervention – Adjunctive Treatment
11:00 AM-12:15 PM, Friday, 27 June 2003 Svenska Massan Exhibition Hall Bhttp://iadr.confex.com/iadr/2003Goteborg/techprogram/abstract_34208.htm
Our histological research supports our new treatment theory, and the images we published in Dentistry Today–that according to the PI of the LSU study.
Furthermore, we are investing in and preparing a multi-centered university-based, prospective, blinded controlled clinical trial of our methodology compared to “gold standard” periodontal treatment methods.
That’s what I mean about science and our commitment to credible research.
Is your company investing in any research to validate the HKS hypothesis, or any such clinical claims being made? Not last I spoke to their reps about it–like at the AAP meeting in San Francisco. None is now underway, and none is even in the plans.
That’s the point of credible commitment to science that separates MDT and what I advocate, and what you seem to be so accepting of, for the simple motive that you have acknowledged–to make money.
My motives start with my patients’ needs and outcomes first, not profit at their expense.
Your reaction to those who challenge your beliefs and the investments you make is so identical to the reactions I have dealt with from other manufacturers over the years when their “sacred cow” was not appreciated–they attack the messangers, and refuse to deal with the message.
Good luck in your next venture……in….whatever. I’ll still be here treating patients, contributing to the clinical and basic science research as it pertains to optimal patient treatments and parameters of care using lasers.
And NO, you can’t invest in our company. I told you before we want to keep it private so we are not beholding to Venture Capitalists who wants to turn, churn, and burn the company for all that it’s worth.:biggrin:
Yours in scientific and clinical laser dentistry,
Robert H. Gregg, DDS