1) The study analyzed temperature changes on root dentin surfaces and in pulp chambers of teeth when irradiated with an Er,Cr:YSGG laser at low fluences, to determine safe parameters for caries prevention.
2) Testing on 20 human teeth found that a fluence of 2.8 J/cm2 did not raise intrapulpal temperatures over 5.5°C and may prevent caries without risk of pulpal damage, while 5.6 J/cm2 raised temperatures above 100°C with greater chemical changes in dentin.
3) In conclusion, a fluence of 2.8 J/cm2 showed potential as a promising parameter for safe caries prevention on root
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Description - Project aims to develop an application that can be used to translate the images of any format to the text format.
Features - It convert the standard font texts and handwritten texts from image files into editable text files.
THE TREATMENT OF INFECTIONS ON TOOTH SURFACES AND IN ROOT CANALS WITH THREE DIFFERENT LASER MODALITIES: Photodynamic Therapy, Photothermal Therapy, Photoablation
Mandibular Third Molar And Inferior Dental Canal- A Tricky SituationQUESTJOURNAL
ABSTRACT: The removal of impacted mandibular third molars is one of the most common surgical procedures performed in routine. Accurate assessment of the position of the inferior alveolar nerve in relation to the impacted third molar might reduce injuries to this nerve. When the inferior dental nerve is in close proximity to an impaction, the nerve is at a greater risk of injury during removal of the impaction. Surgical removal of such impactions is much safer when preceded by radiographic imaging to determine the location of the inferior dental canal.
Osteoradionecrosis is one of the most serious oral complications of head and neck cancer treatment.
It is a severe delayed radiation-induced injury, characterized by bone tissue necrosis and failure to heal for at least 3 months.
THE TREATMENT OF INFECTIONS ON TOOTH SURFACES AND IN ROOT CANALS WITH THREE DIFFERENT LASER MODALITIES: Photodynamic Therapy, Photothermal Therapy, Photoablation
Mandibular Third Molar And Inferior Dental Canal- A Tricky SituationQUESTJOURNAL
ABSTRACT: The removal of impacted mandibular third molars is one of the most common surgical procedures performed in routine. Accurate assessment of the position of the inferior alveolar nerve in relation to the impacted third molar might reduce injuries to this nerve. When the inferior dental nerve is in close proximity to an impaction, the nerve is at a greater risk of injury during removal of the impaction. Surgical removal of such impactions is much safer when preceded by radiographic imaging to determine the location of the inferior dental canal.
Osteoradionecrosis is one of the most serious oral complications of head and neck cancer treatment.
It is a severe delayed radiation-induced injury, characterized by bone tissue necrosis and failure to heal for at least 3 months.
1. HEAT TRANSMISSION ON DENTIN IRRADIATED BY
Er,Cr:YSGG LASER FOR CARIES PREVENTION
Valter Valentim Lula Júnior1, Profa. Dra. Denise Maria Zezell2, Profa. Dra. Patrícia Aparecida da Ana1
1Universidade Federal do ABC (UFABC) - Av. dos Estados, 5001, Santo André, SP
2Instituto de Pesquisas Energéticas e Nucleares (IPEN) - Av. Lineu Prestes 2242, Cidade Universitária, São Paulo, SP
valter.junior@ufabc.edu.br, zezell@usp.br, patricia.ana@ufabc.edu.br
Advanced School On Modern Trends Of Biophotonics For Diagnosis And Treatment Of Cancer And Microbial Control, April 11 to 19, 2013
Abstract. The temperature changes on root dentin surface and pulp chamber of uniradicular
teeth were analysed during Er,Cr:YSGG laser irradiation at low fluences, aiming to determine
a promissory parameter for future clinical application for caries prevention in dentin.
Keywords: Er,Cr:YSGG laser, temperature, caries prevention.
INTRODUCTION
Dentin exposure by gingival recession makes teeth more sensible to pain and more
susceptible to caries lesions (Fig. 1).
MATERIAL AND METHODS
Fig. 1 A) Healthy gingiva showing knife-edge border of the free gingiva that is scalloped
in shape; B) Gingival recession, with dental root exposure due to gingival margin
migration apical to the cemento-enamel junction (SCHEID and WEISS, 2012).
RESULTS
CONCLUSION
According to the obtained results, the fluence of 2.8 J/cm² can be a promissory parameter
for caries prevention on root dentin.
ACKNOWLEDGMENTS
To IPEN for the laboratorial and CEPOF for the accomodation support.
REFERENCES
ANA, P. A. Estudo in vitro da resistência à desmineralização e da retenção de flúor em esmalte dental irradiado
com laser de Er,Cr:YSGG. 2007. Tese (Doutorado) Instituto de Pesquisas Energéticas e Nucleares, São Paulo.
SCHEID, R. C.; WEISS, G. Woelfel's Dental Anatomy. 8. ed. Philadelphia: LWW, 2012.
ZACH, L.; COHEN, G. Pulp response to externally applied heat. Oral Surg., v. 19, n. 4, p. 515-30, 1965
Gingival recession
Root and dentinal
tubules exposure
Severe root caries
and hypersensitivity
Hi-power
laser heating
(Fig. 2)
Chemical changes
in dentin (Fig. 3)
Risk of pulpal
damage
Dentin surface and
pulpar chamber
heating analysis
Safe and effective
parameters for
caries prevention
X
Fig. 2 Absorbance spectrum of the main
componentes of biological tissues, related to
the main laser wavelenghts used in dentistry.
(ANA, 2007).
Fig. 3 Chemical changes in dental hard
tissues after laser heating. According to the
temperature, it is possible to note changes
in water, carbonate and organical material
content, as well as the transformation of
phosphate in pirophosphate, increase of
hydroxyl and formation of new
crystallographic phases, which leads to
decrease of acid solubility (ANA, 2007).
20 incisor human teeth
Pulp removal
Opening of teeth
lingual surfaces
Placing of thermocouple (Fig. 4)
10 teeth in
group A
10 teeth in
group B
Group A:
2,8 J/cm2
Group B:
5,6 J/cm2
Er,Cr:YSGG pulsed
laser irradiation for
20s
Thermocouple and thermographic
camera heat analysis (Fig. 5)
Statistical analysis (Table 1)
Fig. 4 Thermocouple placing.
Fig. 5 Root dentin irradiation.
Fig. 5 Infrared images during radicular dentin irradiation; a) at beginning, b) during
irradiation; c) imediatelly after irradiation; d) during tooth cooling.
Fig. 6 Surface temperature changes
during Er,Cr:YSGG laser irradiation at
2.8 J/cm2.
Fig. 7 Pulpal temperature changes
during laser irradiation detected with
thermocouple
Dentin surface temperature data evidences
Er,Cr:YSGG laser potential on trigger chemical
changes in dentin when irradiated with 5.6
J/cm² fluence, due to temperature raises
above 100°C. Nevertheless, even with less
chemical changes due to lower temperature
raises, 2.8 J/cm² fluence suggests to be more
indicated because it was not induced
intrapulpal temperature raises higher than
5.5°C, without pulpal damage risk (ZACH and
COHEN, 1965).
Laser
Thermocouple
Thermographic
camera
Tooth
Dental wax
0 20 40 60 80 100
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
T(
o
C)
Time (s)
2.8 J/cm
2
5.6 J/cm
2
0 20 40 60 80
20
30
40
50
60
70
Temperature(
o
C)
Time (s)
2.8 J/cm
2