Greetings Etienne,

Nice treatment!

The appearance of the gingival tissues after FRP Nd:YAG lasing shows smart application of energy used–i.e. no recession. I’m thinking you used very little energy, on the order of 30 seconds for that result.

While the tissue still has “issues”, you can always go back and treat again once they firm up and the inflamation has resolved some.

How long between 1st and 2nd appts?

What sort of antibiotics did you prescribe?

Thanks,

Bob

Thanks Etienne,

No, never boring……….

Sounds good. I’m guessing you used 150usec, 20 hz, 3.0 watts for 30 seconds? Less power? What were your settings?

You may not have to retreat that pocket again.

The next time you numb the patient up, I would gently probe. If you meet the slighest resistance, don’t push. Unless or until there is BOP, or inflamation, I would not retreat to the base of the defect. Keep the gingiva clean and “closed”.

I would just use the laser in the canal.

If there is a pocket and/or BOP, I would treat as you did the first time.

Good luck,

Bob

Hi Bob

Good guess!! Actually it was 150usec, 20Hz, 4watt for 20sec.

So about 40 Joules, which is well within the tissue tolerances for that tooth and defect size.  Very smart on your part.

How long would you wait until you decide to evaluate?

30 days for both the RCT and the perio pocket.

I am seeing the patient shortly (next week I think) to complete the endo, would you wait longer?

No, that’s OK.

If you have BOP or a pocket, would you retreat to the base again?

Yes, but not with force.

What would you say were the chances of saving a tooth like this? 50%? 40% Just wondering.

I’d tell the patient 50%, but I’m thinking more like 90%.

Take care
Etienne
Good luck!

Bob

Hi Bob

Thanks very much for your note. Do you truly think the chances of saving a tooth like that is as high as 90%? WOW!!

Yes.

On another note, do you think the same effect could be reliably achieved using another kind of laser? Say for instance a diode?

No, not reliably……occasionally, not reliably.

My gut feel is that the difference in wavelength is not that important but the difference in gated pulse vs free running pulse is crucial. What are your thoughts regarding this?

I agree completely

Thanks!

Take care

Etienne

Thanks, you too.

Bob

Hi Bob

So the peak power value is the important thing if I have this correct.  

 Yes.

Squeezing the same amount of energy into a shorter pulse, with assosiated long pulse delay (thermal relaxation time) is what is helping us here?

Squeezing the same amount of average power into short pulse duration AND the pulse interval (say of 20 Hz) gives you the mathmatical ratio (duty cycle) between peak power and thermal relaxation, and the biological balance for what you did.

The ratio of “on” to “off” time (duty cycle) is 0.3% if we use your PD of 150 divided by 50,000 usec in a second at 20 Hz.  So your laser is on for 0.3% and off for 99.7% yet delivers 1500 watts of peak power at 3.00 watt and 20Hz.

Is there an ideal correlation between pulse delay and pulse energy and total energy for different situations, say endo, perio etc?

Yes, we believe so.  Optimal combinations of parameters for achieving different clinical objectives?  Yes.

Take care
Etienne

Thanks.  You too.  Bob

Nice endo. Time will tell………

Take care,

Bob

Etienne,

Such a typical dentist!

Instant gratification you want? LOL! We were all trained that way. Unlike physicians.

Great things take time to realize. Like waiting for the sun to come up, then it’s always darkest right before dawn.

Take care my friend,

Bob