Glenn,
A recent article by Ron Kurthy(?) sorry Ron on the spelling, states that a product like Touch and Bond will seal up the tubules and that’s it.  I have a lady coming in in the next couple of days with serious sensitivity.  I thought I would try the bonding on one side and the laser on  the other to see what results.  I have had dependable results from the laser but not necessarily complete elimination of sensitivity in all cases.  

I have noted the patient usually feels the 0.25W but saw that as a negative and backed off.  As you indicated Ron maybe this is the feedback of successful sensitivity reduction in that area.

Pat

I second the notion of starting a long distance away and to also always keep the tip moving. I usually tell the patient that as soon as they start to feel it get warm to raise a hand so I can back off. I tell them I need to have them feel this to know we’re getting the actual sensitive area. Once backed off I pause a few seconds and get the patient to run their tongue over the area. Then I start circling in again.
I have had 1 person (20 buccal, cervical) who couldn’t stand even .25 0/0 from any closer than the 10mm-he said this hurt and I could tell it wasn’t acting on his part.Couldn’t even rinse with tap water it was so touchy. Just decided to numb him up- infiltrated some Septocaine and finished with the laser.

Great post bob , thanks for sharing , challenging and teaching.

Here is 1  proposed method http://www.karna-ddscomfordent.com/LLLT-2.htm. I haven’t done this mainly because I was concerned (that using the diode and its absorption by pigment) about the tissue effect from tissue surface to the apices. I also thought 15-20 seconds of stimulation in 1 area w/o moving seemed quite long. Why direct at apices (and overlying tissue)and not pulp chamber itself? I also couldn’t find anything that supported this method.

Lee,

Thanks for the kind words.

Dentin and/or root hypersensitivity may involve more than just pulpitis.  See the article below on some theories.

If you de-focus at a distance away from the tooth, you can get some thermal energy into the tubules and have a “biomodulating” effect on the action potentials of the OD processes and the unmylenated C fibers in the pulp–it seems.

Occluding the tubules alone give us mixed results….around 50%.

Defocusing and “biostimulating” the pulp/tubules gives us 90+%

The sensitivity typically stays at the level of chairside treatment, however the patient may become dissatisfied if only 75% versus 95%.  Some others may feel that is just fine……

One VERY common observation post-op to de-focused laser desensitization is that an ache or throb–usually mild–appears within a few hours post-op that can increase in intensity for a few days, then tapers off slowly over a week or two.  VERY common observation.

Hope that gives you a “jump”!!

Bob

Dentinal Sensation and Hypersensitivity A Review of Mechanisms and Treatment Alternatives  Louis H. Berman

In any dental procedure, in the absence of local anesthesia, manipulation of dentin surfaces may cause pain. When dentin is exposed to thermal, osmotic or electrical stimuli, or when air blasts or various drugs are applied to its surface, the host feels pain which may be termed a “dentinalgia.” A “pulpalgia” is a more prolonged, chronic pain to given stimuli and may result from a rise in the local intrapulpal edema subsequent to deep caries and pulpal inflammation.1,2 Although histochemical, autoradiographic and electron microscopic studies have vividly described the relationship between the odontoblast and the neural fibers of the pulp, the exact mechanism of transmission of the pain response from the dentin to the terminal nerve endings is only hypothesized. Four theories have been proposed: the transducer, modulation, gate control and hydrodynamic theories.3,4 Of these theories, the hydrodynamic theory is currently believed most responsible for the transmission of dentinal sensation. However, a brief description of the other mechanisms will also be presented.

Transducer Theory. This theory of dentinal sensation takes into consideration the “synaptic-like” relationship between the terminal, sensory nerve endings and the odontoblastic processes. If a true synapse were present between these two elements to facilitate the transmission of dentinal sensations, then a neural transmitting substance such as acetylcholine would be expected in this area of the odontoblastic process and the predentin. There is no direct evidence for the presence of acetylcholine activity in the neural transmission in the pulp.

Modulation Theory. Upon an irritating stimulus to the dentin, the odontoblasts may become injured and subsequently release a variety of neurotransmitting agents as well as vasoactive and pain producing amines and proteins.5 These substances may modulate associated nerve fiber action potentials by increasing neuronal cAMP levels through cell membrane adenylate cyclase receptors.6

Gate Control Theory and Vibration. When the dentin is irritated, for example, by cavity preparation, all of the pulpal nerves become activated from the vibrations. The larger myelinated fibers may accommodate to the sensations. The smaller C-fibers may tend to be maintained and not adjust to the stimulus. Thus, as the low-intensity “pain gates” from the larger fibers are closed, the high-intensity “pain gates” from the smaller fibers are enhanced.3

“Pain gates” may be opened by some stimuli, such as anxiety, and may be closed by distracting stimuli such as “audio-analgesia” or gingival stimulation. Van Hassel2 demonstrated in monkeys that cortical responses to pulpal stimulation can be diminished by concomitantly stimulating the gingiva.

However, the gate theory does little to explain how pain responses from the dentin are transmitted and perceived by the nerve endings of the pulp—only how they may be centrally interpreted.

Hydrodynamic Theory. Fish in 19278 observed the interstitial fluid of the dentin and pulp, referring to it as the “dental lymph.” He postulated that the flow of this fluid could take place in either an outward or inward direction depending on the pressure variations in the surrounding tissue. Isokawa9 found no pulpal lymphatics in dog teeth, but suggested that the pulpal lymph flow was continuous with that of the dentinal tubule fluid. This idea of fluid movement within the dentinal tubules is the basis for the transmission of sensations according to the hydrodynamic theory.

Short-term stimulation of the dentin and the resulting pain, a “dentinalgia,” is not necessarily the result of local changes in the intrapulpal pressure. According to the hydrodynamic theory, as put forth by Brannstrom and Astrom,11 a dentinalgia results from a stimulus causing minute changes in the fluid movement within the dentinal tubules. This may subsequently deform the odontoblast or its process and hence cause an elicitation of pain via the intimately associated “mechano-receptor-like” nerve endings.

Mjor and Pindborg12 stated: “Pulp and dentin sensation is characterized by being limited to pain only, irrespective of the initiating factor.” There is no direct support for any type of specialized terminal nerve receptors for hot, cold, electrical, osmotic, dehydration or chemical stimuli in dentin. The interpretation of most of these stimuli can be explained by the hydrodynamic theory. Figure 1 will help to visualize this model, as explained below.

The dehydration of dentin (i.e., by air-blasts) is probably the clearest example for understanding dentin sensation. When Brannstrom applied absorbent paper to exposed dentin it caused pain; but no pain was elicited using wet paper.11,13 The outward movement of the dentinal fluid into the dehydrating source (i.e., air-blasts or absorbent paper) is thought to stimulate the “mechano-receptor” of the odontoblast, causing pain.

The perception of acute thermal stimulation can also be explained by the hydrodynamic theory. The coefficient of thermal expansion of the dentinal tubule fluid is about ten times that of the tubule wall. Therefore, heat applied to dentin will result in an expansion of the fluid, and, conversely, cold will result in a contraction of the fluid, with both creating an excitation of the “mechano-receptor.”14,21,25 This fluid-flow model is further reenforced by the finding that pain is felt before temperature changes can be measured on the pulpal side of the dentin.15
It is also a common clinical finding that pain is produced when sugar or salted solutions are placed in contact with exposed dentin. When the irritant is rinsed or brushed away, the discomfort subsides.10 This again can be explained by dentin tubule fluid movements. Fluids of a relatively low osmolarity (i.e., dentinal tubule fluid) will have a tendency to flow towards solutions of higher osmolarity (i.e., salt or sugar solutions). When iso-osmotic solutions are applied, no stimulus is felt.

Source: Journal of Periodontology on CD-ROM (Copyrights © 1998, AAP), 1985 Apr (216 – 222):

Yesterday I had a young woman with extreme ypersensitivity on a #29. At .25W 0/0 I couldn’t get within an inch of the tooth. I held the tip outside the mouth , retracted the lip and attempted to apply laser energy in a very defocused mode. At that distance it was difficukt to tell if I was aimed at the correct part of the tooth, but she was able to tell me. I eventually anesthestized, lasered area and placed duraphat.
I also have one other patient who has the most severe hypersensitivity post perio treatment that I ever saw.
I attempted desensitizing teeth during my training session with zero success. After reading many posts online I have subsequently attempted treatment also with zero sucess.
These were two failures, I have had several sucess stories, but when I hear people talk of 100% sucess it makes me wonder.
Comments and sugestions appreciated.
GO JETS!

Hi Guys,
For what it’s worth, I have never heard anyone talk of 100% success without anesthesia. Honestly, I have had to anesthetize 8 people since last Feb. I counted over 2000 procedures where I haven’t had to use any anesthetic. The answer seems to be patience. Defocus, and have patience with the “numbing” effect. It’s not perfect, like Pat says, and some “feel” something. Never promise it won’t hurt at all, BUT, always ask afterwards, would they have wanted the “shot” and “drill” or the laser. I do ask, and so far, 100% have said, LASER! No joke. If you use your laser alot, you will get proficient, if you don’t it’ll seem like it takes forever to get the learning curve down. HAVE PATIENCE. You will get the curve down, and when you do, it’s incredible. My 2 cents Montanan’s worth! Hope everyone is having a great New Year so far!
Mark

One other thing. Lasers are very sensitive devices. They change in their calibration periodically. IF you are having some sensitivity issues, have the technicians come out and reset your PK’s. This morning, my Biolase tech just happened to be in the area, and I have been getting a touch more sensitivity lately. We set these a number of months ago, and the values were fine. We found out this morning, that my laser has gotten a bit “hot”, so it could be in the software, or wherever, but that explains why I have had a slight difference. I bet I see a difference with the new calibrations. Laser dentistry is so exciting, and new, and we just have to put up with the learning we need to do each time we pick up the handpiece. Not the same as a turbine needing to be replaced huh? I will let you all know how the new calibrations work out. Really, Biolase has been great in their support, and I can’t say enough. I really haven’t had much problems at all with my Waterlase, this is very minor, but again, another part of the learning curve for all of us.
Glenn, I know your unit has variable Hz settings, BUT with the power adjustments, do you have to, or have you had, your unit calibrated every once in a while, and if so, have you seen any variations in Wattage output after a few months/year of use? We have been advised to have our units calibrated at least once per year, I have mine done more often, because I use it for ALL procedures I can, it’s my workhorse, so I feel the need to check it now and again. This is the only time I have had to have it reset (it got a bit hotter in the Wattage settings). Just wondering.
Hope everyone is having a great Year!!
Mark