Influence of microwave sterilization on the cutting capacity of carbide burs.
OBJECTIVE
This study compared the cutting capacity of carbide burs sterilized with microwaves and traditional sterilization methods.


METHODS
Sixty burs were divided into 5 groups according to the sterilization methods: dry heat (G1), autoclave (G2), microwave irradiation (G3), glutaraldehyde (G4) or control - no sterilization (G5). The burs were used to cut glass plates in a cutting machine set for twelve 2.5-min periods and, after each period, they were sterilized (except G5) following the protocol established for each group. The cutting capacity of the burs was determined by a weight-loss method. Data were analyzed statistically by Kruskal-Wallis and Dunn's test.


RESULTS
The means of the cutting amount performed by each group after the 12 periods were G1 = 0.2167 +/- 0.0627 g; G2 = 0.2077 +/- 0.0231 g; G3 = 0.1980 +/- 0.0326 g; G4 = 0.1203 +/- 0.0459 g; G5 = 0.2642 +/- 0.0359 g. There were statistically significant differences among the groups (p<0.05); only dry heat sterilization was similar to the control.


CONCLUSIONS
Sterilization by dry heat was the method that least affected the cutting capacity of the carbide burs and microwave sterilization was not better than traditional sterilization methods.
Fais
Laiza Maria Grassi
LM
Department of Dental Materials and Prosthodontics, São Paulo State University, Araraquara, SP, Brazil. laizamgfais@foar.unesp.br
Pinelli
Lígia Antunes Pereira
LA
Adabo
Gelson Luis
GL
Silva
Regina Helena Barbosa Tavares da
RH
Marcelo
Caroline Canhizares
CC
Guaglianoni
Dalton Geraldo
DG
D002244:Carbon / Q000737:chemistry; D019551:Dental Disinfectants / Q000627:therapeutic use; D003762:Dental Instruments; D004867:Equipment Design; D004868:Equipment Failure; D005898:Glass / Q000737:chemistry; D005976:Glutaral / Q000627:therapeutic use; D006358:Hot Temperature; D006801:Humans; D008422:Materials Testing; D008872:Microwaves / Q000627:therapeutic use*; D013193:Stainless Steel / Q000737:chemistry; D013242:Sterilization / Q000379:methods*; D013499:Surface Properties; D013997:Time Factors
D019551:Dental Disinfectants; D013193:Stainless Steel; D002244:Carbon; D005976:Glutaral