18. Minimally invasive techniques in the preparation of cavities

Question 1

1. Basics
   a/ Background of minimally invasive techniques?

Answer 1

1/ Minimal intervention dentistry (MID) is a growing trend in all fields of dentistry
2/ Minimally invasive techniques are part of conservative dentistry.
3/ “Extension for prevention” based on Black principle is replaced with “minimally invasive”
4/ Minimal intervention in dentistry has been introduced by Davis and Makinson in 1992

Question 2

2. What are the 5 most common Minimally invasive techniques in the preparation of cavities?

Answer 2

1. Enamel abrasion
2. Air abrasion
3. Ultrasonic/sonoabrasive preparation
4. Laser preparation
5. Using rotary instruments

Question 3

3. Enamel microabrasion
   a/ What are characteristics of enamel microabrasion?

Answer 3

◦ Removal of the surface stains on the enamel layer (until 0.2 mm depth)
◦ Clinically usable in cases of enamel hypocalcification, hypoplasty, fluorosis or demineralization
◦ This treatment can also be completed by adhesive filling therapy in the operative field

Question 4

3. Enamel microabrasion
   b/ What is the principle of enamel microabrasion?

Answer 4

decalcification of the enamel (with 6% hydrochloric acid), then removal of a 20-25 micrometer thick layer from the surface (with SiC abrasive paste)therapy in the operative field

Question 5

4. Air abrasion
   a/ Characteristics and mechanisms of air abrasion

Answer 5

1/ Minimally invasive cavity preparation technique-without drilling
2/ Mechanism of action: blowing of 27 -50 micron aluminum oxide particles with air pressure onto the tooth surface

Question 6

4. Air abrasion
   b/ What is the usage of air abrasion

Answer 6

1/ Preparation for fissure sealing
2/ minimally invasive treatment of fissure caries
3/ Surface roughening for adhesive procedures

Question 7

5. What are characteristics of Ultrasonic/sonoabrasive preparation?

Answer 7

1/ Ultrasonic or sonic, pneumatic preparation instruments
2/ Various working heads for each cavity design
‣ Endodontics
‣ Inlay preparation
‣ Approximal cavities
3/ Controlled tooth structure removal, with maximum protection of the neighboring teeth

Question 8

6. Laser preparation
   a/ what are the characteristics and action mechanism of laser preparation?

Answer 8

1/ Possibility of selective tooth preparation and caries removal - without vibration and sensibility

2/ After preparation, the surface will be rough, with opened dentinal tubules -> good for adhesive techniques

3/ Mechanism of action: the carious tissues with high water content will be removed with ablation

Question 9

6. Laser preparation
   b/ Which type of laser is the best for cavity preparation and caries removal? Examples?

Answer 9

◦ Erbium laser (with infrared wave length) is the best for cavity preparation and caries removal
‣ E.g, Er - YAG; Er - YSGGremoved with ablation

Question 10

7. Characteristics of using rotary instruments?

Answer 10

1/ Use of a special burr, which guarantee a controlled and minimally
invasive reduction of tooth structure

2/ Use of the operative microscope and various loupes in the modern dentistry
‣ Cavity preparation
‣ Endodontics
‣ Minimally invasive prosthodontics: preparation and cementing