#17 – Diagnodent

Diagnodent (Customer Service 1-800-323-8029)

Today, fluoride has made enamel so hard that it is difficult to detect occlusal decay. Small defects can hide significant decay. The Diagnodent is a laser caries detection tool.

*The Diagnodent is actually more accurate at detecting decay than the metal probe dentists have used for over 100 years. However, the reading only shows what has happened in the past, not whether the tooth is undergoing active decay now.

X-rays are also a problem. X-rays are accurate on the mesial and distal, but on the occlusal you are looking through a superimposed view of the entire biting surface. Research in 2001 showed tht x-rays weren’t consistently accurate in diagnosing occlusal decay until it had advanced 3mm through the tooth.

Your decision on whether the tooth can be healed or be restored should be based on the client’s decay activity and home care.

Set Up
1. Make sure cable is screwed tightly into unit.
2. Select tip – attach by gently rotating/pushing. DO NOT push or pull straight onto sheath. It will break the tip. These tips are $85 each.
3. Cover tip with plastic intraoral camera barrier. Use an exploring point to open small hole so tip of probe will be exposed through barrier. Do not push the tip through the sheath – you will break the tip! Make sure barrier is not turned on the more opaque side.
4. Push on side of gray ring to turn on. (turns off automatically)
5. Prior to use, place tip on yellow ceramic disk. If the reading is + 3 of the number on the disc, go ahead and use on the tooth, if not, calibrate the unit.

1. Set speaker control volume at 2 (press symbol – “peak” will show 2)
2. Press ABC button until “A” lights (designates using “A” tip)
3. Calibration
a. Press CAL – once – will show 0 in moment and peak (wait for noise to begin)
b. Put tip lightly on gold circle embedded into black stand that holds extra tip. Give gray ring a constant squeeze.
c. Moment will show a 2 digit number and “b” on peak, hear tone-when tone stops calibration is complete
d. Compare display moment/peak numbers with disk numbers. Should be +/- 3 units of numbers on gold circle, tone stops.

e. Error sign usually means
1. Cord isn’t in correct position. Remove and reattach.
2. Tip is broken or coated (try another tip)
3. Calibration done incorrectly
4. Make sure batteries are loaded properly
5. Make sure tip is seated properly. It should be flush with the sheath
6. Try another tip (it may be broken)
7. No moisture on tip or sheath (if autoclaved)
8. Go ahead and recalibrate after checking

(Can be used around edges of sealants or fillings, but not through them)
1. Tooth must be sandblasted and dry (prophy paste and debris give false positive by Laser reflections).

2. Standardize setting
a. Pick middle third of facial surface of healthy, non-restored anterior tooth. Dry tooth with a 2×2. Give the gray ring a constant squeeze – reading should be –5 – +2.
b. Hold probe at right angle for 2 seconds.
c. Gently press gray ring with constant pressure.
d. You will hear 2 beeps and “Set 0” should appear on screen (baseline established).
e. Record this: “Diagnodent zero baseline #8 mid facial—”

3. Eliminate influence of baseline: hold tip in air, press gray ring until “Set 0.” Do this once per client.

4. Tell client “A healthy tooth makes no sound.” The higher the sound the worse the decay. The audible sound starts at 9. The sound gets higher the larger the number. If you hear a high tone, scan this area more carefully.

5. Place tip on tooth with light contact. Even moderate pressure can break the tip.

6. In fissures, slowly rock tip in all directions. Don’t drag tip over tooth.
a. Place the tip directly on the restoration and note the reading. Then as you go around the margins,
look for a significantly higher reading (15-20 moves).
b. Moment – reading at that exact moment in time
c. Peak – highest number for that tooth

7. Diagnodent is not accurate for proximal decay.

8. Diagnodent can not read through a restoration, but you can read around the edges. Place the tip on the restoration and get a reading. Then place the tip on the edge and subtract the restortation number from the edge/potential scan number.

9. Don’t scan every tooth – only the suspicious ones.

10. Document on the yellow exam sheet
a. Baseline tooth
b. Peak reading for every tooth checked.

11. Use the tone change to alert you to look at LED number. If you get a higher reading, scan this tooth
more carefully.

12. Readings
0 – 15 Healthy
16 – 20 Recommend sealant
21+ 40 Watch and retest in 6 months if no other signs (x-ray, cavity, etc.)
80+ ERRORS – see calibration section

13. Interpretation of readings
a. Dark areas on primary teeth reading 30+ restore
b. Dark areas on permanent teeth lead to higher (false) readings – look for other diagnostic factors
between readings of 35-45. If no visible, probable, or x-ray indicators, note the tooth on the chart
and check again in 6 months.
c. Actual cavities won’t record with high numbers since the lesion contains debris that interferes with
laser transmission.

d. False readings will be caused by
1) Stain, calculus
2) Prophy paste, abrasive cleaning particles
3) Composite

14. Record the number on that tooth and squeeze the gray ring to clear the peak value. Go to the next
15. Rotate to remove tip from hand piece.

16. Steam sterilize can be done in cassette but barrier protect is better.

17. To steam sterilize, place tip on cassette.

When to use the Diagnodent

 All NPs with CMS, 5 year reviews
 Before all sealants
 When doc requests or if an alert noted on the control program form
 If we are watching a tooth – then run at each cleaning visit.
 If RDH thinks occlusal decay, then run diagnodent for the doc to know the reading.

** Be very careful of tubing (cost $1500). Don’t roll up or kink. Tips are fragile. Don’t push too hard on the tooth or they will break ($85).

___________________________ __________________
Advanced c/s Date