We sat down with Dr. Rod Kurthy, developer of the Deep Bleaching tooth whitening protocol, which combines in-office treatment, at-home trays, and permanent maintenance. He tells us how he “discovered” the technique, what it is, and why it works.
Dentalcompare: Can you give us a little background, what motivated you to develop the Deep Bleaching technique and what was your process?
Rod Kurthy: In 2001, I was challenged with a unique case—I did a complete smile makeover (multiple veneers) on a patient, who was just thrilled with her new smile. She referred her 28-year old daughter for similar treatment. This young woman, however, had beautifully straight teeth and great occlusion, but her tooth shade was something I’d never seen before. While the background was something between A1 and A2 shade, about 60% of the surface of her teeth were covered with what I can only describe as swirls the color of a Hershey bar! I don’t know what caused it and I’ve never seen anything like is since, but at the time I was convinced that she was definitely not a candidate for bleaching.
However, in keeping with my minimally invasive philosophy, I knew I’d have to lighten these teeth to have success with the least amount of tooth reduction and thin veneers. After some thought about this unusual case, I decided to start with an in-office treatment, and then I sent her home for a regimen of nightly tray wearing, to be followed up by another session of in-office bleaching. To my amazement, when she returned for the second visit, there was about a 50% shade lightening. And after the second in-office session, there was not one trace of brown left.
Well, we were both crying. Hers were tears of joy and mine were because I just bleached myself out of a 20-veneer case! But of course, I was thrilled.
DC: Can you describe the general protocol for the Deep Bleaching technique and detail how it is different from conventional in-office whitening procedures?
RK: The technique has evolved over the past 8 years; in fact, the Deep Bleaching manual is in its 9th edition since 2003. The reason for this evolution is that I keep learning from my own cases and the thousands of cases from other doctors who do Deep Bleaching. Where we are right now is embodied in our proprietary KöR Deep Bleaching System. The protocol all starts with, and is greatly based on, an extremely detailed impression. When taking impressions for bleaching trays, I think many dentists adopt what I call the “just” attitude: “It’s JUST a bleaching tray.” Well, for the Deep Bleaching procedures, we need impressions that not only capture exceptional details of the teeth, but also exceptional accuracy of the gingival margins. With the impression technique I developed, we even get an impression of the sulcus, and this is critical for the tray construction.
An accurate impression is the first step to success with Deep Bleaching. |
In Deep Bleaching, the cornerstone that allows all the other steps in the process to be so effective is the Deep Bleaching Trays themselves. If our goal is to have hours of continuous release of oxygen , we need to not only create permeability, but permeability deep within the enamel rod complexes. The trays must meet several criteria, all of which will result from precise impressions and proper fit. The trays must:
- Seal in the bleach (don’t let it leak out of the tray)
- Seal out saliva and sulcular fluid (both of which destroy bleach). One of the biggest causes of poor bleaching results is using trays that cover the gums and literally drag the sulcular fluid into the tray, destroying bleach).
- Be comfortable and unobtrusive to promote patient compliance for overnight tray wear. When a tray is so comfortable that they can’t feel it, and when it seals in bleach so they don’t constantly swallow it – all of a sudden your patients don’t mind wearing these trays during sleep. And nighttime wear is more effective than day wear because salivation slows dramatically. An added bonus—they’re practically invisible, too.
- Incorporate reservoirs. I know there is debate about this, but from my experience, regular bleaching trays do NOT seal out saliva, and I don’t care how large your reservoir is, if saliva contaminates it, it is of no benefit – BUT when you CAN seal out saliva, an extra reservoir of bleach works incredibly well)
The Deep Bleaching tray seals in bleach, seals out fluids,
and is practically invisible. |
DC: Now that we have the proper trays, what’s the timeline?
RK: Here’s a general outline of how it works in my practice….
- At the first bleaching visit, patients wear their trays in the office for the initial treatment. We use an accelerated 9% hydrogen peroxide (which probably provides the effectiveness of 20% hydrogen peroxide). Trays are worn for two 20- minute sessions, with bleach changed in between (changing the bleach is crucial, because the accelerant works so quickly). No dam or retractors required.
- We send the patients home to wear trays for 14 consecutive overnight sessions with unaccelerated 16% carbamide peroxide.
- During the final visit, we apply 27% accelerated hydrogen peroxide for an intense burst of oxygen and maximum whitening. Retraction and paint-on dam is required for this. This extremely high-strength blast is the basis of the KöR Whitening Deep Bleaching™ MAX system, named because it does provide the maximum amount of shade change possible. This is for dentists like me who want to totally knock the socks off ALL of their patients. Deep BleachingTM is a super-charged bleaching system as it is, and this is the top of the top!
As a less labor intensive alternative, I have developed the KöR Whitening Deep Bleaching™ STANDARD Kit. The only difference is at the final appointment. Instead of the 27% strength, we repeat the process from the first appointment—tray-delivery accelerated 9% hydrogen peroxide. The results are still terrific.
DC: So now the question of the hour—why does Deep Bleaching work so well?
This severe case of tetracycline staining was dramatically improved with Deep Bleaching. |
RK: It’s the “deep” in Deep Bleaching….conditioning the teeth on the first visit and slow, time-released exposure during at home wear creates a deep cleansing effect, maximizing penetration of whitening agent into enamel crystal complexes. It’s all about permeability of the enamel to those itsy-bitsy oxygen radicals. I don’t care HOW strong the bleach is, if it’s hydrogen peroxide or carbamide peroxide, or what brand you use. If that tooth structure is NOT permeable to the oxygen, nothing’s gonna happen. The oxygen, and thus the bleaching effect, will just evaporate into the atmosphere. The longer bleach is in contact with teeth, and the stronger the bleach is, the faster it will not only bleach where it can reach, but the faster it will scrub out the debris within the matrix of the enamel rods to allow deeper and deeper bleaching, which means whiter teeth and a longer lasting result (thus the term Deep Bleaching).
The realization of these factors is what led to my development of Deep Bleaching. After years of clinical study, we were able to uncover these things and a lot more. We took the physics of what is going on and worked them around to our advantage.
Additionally, the bleaching gel must have ideal characteristics— 1. Proper viscosity (if bleaching gel is TOO viscous, the oxygen can’t get out of the gel as easily) 2. Proper solubility (if bleaching gel is TOO insoluble, the oxygen can’t get out of the gel as easily) 3. Proper rate of oxygen release (we want it to last for hours). Because the Deep Bleaching trays seal so well, the KöR gels can be less viscous and less soluble.
DC: What about touch-ups?
Not just the doctor, but the patient….Dr. Kurthy had great results with his own congenitally dark teeth. |
RK: I don’t like the term touch-up. It implies that we allow the teeth to regress and then attempt to bring them back to immediate post-bleaching shade. That’s a losing proposition. Long term maintenance is an integral part of the Deep Bleaching technique…it’s not an add-on or afterthought. I tell my patients that Deep Bleaching is permanent, even if they drink red wine and coffee. The process has conditioned/cleansed the teeth so well, that we can maintain the effect by wearing trays one night a month with the 16% carbamide peroxide. Why? The teeth became “conditioned” during the first bleaching you did some time ago. You’ve heard that term, but probably never really knew what it meant. “Conditioned” just means “permeable”. Because the tooth structure is permeable to oxygen (because of the bleaching you did a year ago) this time the bleach permeated the tooth structure much more easily, rapidly and thoroughly.
Of course the wear time for maintenance varies patient to patient, so we adjust as needed. Some patients can maintain by wearing the trays once every three months, others may need to wear them more frequently than once-a-month. Incidentally, a nice side benefit of this is that patient compliance for regular recall appointments increases because they need refills for maintenance.
DC: This conditioning process—doesn’t it increase the risk of sensitivity?
RK: We have addressed and solved this beautifully. Initially, the great majority of questions and concerns I heard from doctors—those who were doing Deep Bleaching AND those who were not—were related to sensitivity. So I took the challenge and after more than four years of research, developed two products to combat the sensitivity issue.
Remember, the longer bleach is continuously in contact with tooth structure, and the more concentrated it is, the better and deeper it will whiten and “condition”. BUT…it also dislodges the plug of the dentinal tubules. One of the common remedies is potassium nitrate, which works chemically and does nothing to plug tubules.
Managing sensitivity requires paying attention to the physics of tooth structure…the rigidity of enamel versus the flexibility of dentin, the configuration of the enamel rods, etc.
We have developed two products—an inorganic oxalate that both desensitizes and expedites whitening by conditioning teeth to uptake oxygen faster, and a HEMA-based agent that plugs tubules to prevent sensitivity.
 |
 |
| A 65-year old coffee lover before and after Deep Bleaching. |
DC: Are there any contraindications for the Deep Bleaching technique?
RK: Basically they’re the same conditions that would contraindicate traditional bleaching in my practice…women who are pregnant or nursing, the presence of anterior composite or ceramic restorations (unless the patient is willing to replace them), allergy to the materials, patients younger than 14 (and honestly, that’s only because teeth have not typically erupted fully and the chance that further treatment would be needed is pretty likely). I had congenitally dark teeth, and unfortunately my son inherited them. When he complained at age 11 that kids were making unkind comments about his teeth, I started bleaching his teeth. And of course, because I’m his dad, it’s no problem! Every six months or so I can made him a new set of trays so he could continue bleaching with a couple of nights of wear. Because younger teeth bleach more easily, he was able to attain the full effect and easily maintain the bleached shade by the time his teeth were fully erupted.
DC: What was the driving force behind starting Evolve Dental Technologies and the KöR brand?
RK: Doctors have been asking me to provide a place where they can get virtually everything they need for Deep BleachingTM instead of having to go to various companies, and we’ve done that. Our products have been selected and developed by me to specifically have the exact physical properties (that I described earlier) necessary for the very best results with Deep Bleaching.
And here’s another really important issue that I solved by having my own company: ALL bleaching gels are unstable. They’re supposed to be. That’s why they will give up their oxygen rapidly when placed in the mouth. But this instability has a downside too. These products start to degrade immediately after their manufacture. The only way to prevent the degradation is refrigeration, but that is very expensive as you will see. And even more important than refrigeration is the protection from high heat, which destroys bleach very rapidly. I believe that the lack of refrigeration and protection from heat is why we dentists complain of varying effectiveness of bleaching gels that we receive. We all know how HOT it can get in warehouses and inside freight shipping trucks. Evolve bleaching gels (hydrogen and carbamide peroxides) are: refrigerated immediately after manufacture and during freight shipping to Evolve (I insisted on and arranged this special handling with the factories). They are refrigerated at our warehouse and then shipped to dentists in thermally insulated foam boxes with cold packs.
It was always my strong opinion that this was important, but there was no way for me to ever test it. As much of a difference as I thought constant refrigeration would make, it’s turned out to be even more impressive than I had imagined. All of our bleaching gels are provided in plastic containers so that we can keep them under constant refrigeration without condensation damage to paper boxes. The first thing that most dentists ask me when they hear this is, how much more do we charge because of all the refrigeration? The fact is that we don’t charge ANY more at all. It’s something I believe in very much, so we just do it. I am a practicing dentist and I am just as interested in whether or not a product will work as I am in making a profit from it.