The impact of Εr:YAG laser irradiation on the S. mutans of prepared dental cavities.

Postgraduate Thesis uoadl:1721829 611 Read counter

Unit:
Κατεύθυνση Οδοντική Χειρουργική (Κλινικές Ειδικεύσεις)
Βιβλιοθήκη Οδοντιατρικής
Deposit date:
2017-07-14
Year:
2017
Author:
Vierou Oselia
Supervisors info:
Τζούτζας Ιωάννης, Καθηγητής, Τμήμα Οδοντιατρικής, ΕΚΠΑ
Κακάμπουρα Αφροδίτη, Καθηγήτρια, Τμήμα Οδοντιατρικής, ΕΚΠΑ
Χαμπάζ Μαρουάν, Καθηγητής, Τμήμα Οδοντιατρικής, ΕΚΠΑ
Original Title:
Η επίδραση του Εr:YAG laser στο S. mutans σε παρασκευασμένες οδοντικές κοιλότητες
Languages:
Greek
Translated title:
The impact of Εr:YAG laser irradiation on the S. mutans of prepared dental cavities.
Summary:
The aim of this study was to compare the antibacterial activity of Er:YAG laser against a chlorhexidine gluconate-based cavity disinfectant when used as cavity disinfectat agents before the application of the restorative materials. A cavity tooth model test was used for this purpose.

MATERIAL AND METHODS
40 caries-free human extracted third molars were used for the purpose of this in vitro study. Enamel and dentin was removed from the occlusal part of the teeth, with a horizontal section, to obtain flat dentinal surfaces by using a low-speed diamond saw. Two cavities (diameter 2 mm, depth 2 mm) were prepared in the flat prepared occlusal surface of each tooth using a cylindrical shaped diamond (S6830L, 012/4mm, Gebr Brasseler GmbH & Co KG, Lemgo, Germany). After the preparation of the cavities the teeth were sterilized in an autoclave for 20 min at 1210C (Τuttenauer autoclave, Ind Area Givat Shaul B. Jerusalem 93875, Israel). After sterilization, the teeth were incubated in broth culture of 1.5x108 CFU/ml of S. mutans (ATCC 25175) at 37 0C for 48 h to allow bacterial invasion into the cavities.
Following, Er:YAG laser of 2940 nm wavelength (Smart 2940 Plus, Deka, Calenzano, Firenze, Italy using the following parameters (energy 100mJ, frequency 20Hz, pulse duration 700 μs, tip diameter 1mm, total irradiation time under water spray conditions 30 sec.) and a chlorhexidine gluconate-based cavity disinfectant (CHX/Eudent ED-clean 1,8- 2,2%, Intermed S.A. Pharmacautical Laboratories, Attica, Greece/ application time 30 sec) were applied separately on one of the two infected cavities, whereas the second cavity of each tooth was used as control. Three sterile paper points were used to collect the remaining bacteria from the cavities after the application of the disinfection method chosen. Continuously, a suspension with the three collected paper points was prepared using 0,9ml of sterile saline solution. The number of S. mutans recovered was determined by the classical bacterial counting method using TCY agar (tryptone, yeast extract, cysteine, 20% sucrose, 0,2U/ml bacitracine) incubated at 370C, for 48h, at CO2 atmoaphere.
Statistical analysis was carried out using Kruskal Wallis analysis of variance and Post hoc test (p = 0,05).

RESULTS
A statistically significant differences were observed among the data obtained from the three evaluated groups (Control group, Er:YAG laser group and CHX group)(p>0,05). The results of the control group showed in average colony counts of about 8,5 x 105 CFU/ml whereas for the experimental groups the average were 6 x 103 CFU/ml for the laser group and 0 for the CHX. Rating the results in colony counts log-steps reduction, the laser application in the infected cavities was able to reduce the bacterial number by 2log10 CFU/ml whereas in the group of chlorhexidine application the average reduction was 5 log10 CFU/ml.

CONCLUSION
In conclusion, the two cavity disinfection protocols applied for the purposes of this in-vitro study were able to reduce the total viable number of bacteria of the infected cavities in a statistically significant amount in comparison to the control group.
Main subject category:
Health Sciences
Other subject categories:
Dentistry
Keywords:
Er:YAG laser, S. mutans, chlorexidine
Index:
Yes
Number of index pages:
2
Contains images:
Yes
Number of references:
213
Number of pages:
101
File:
File access is restricted only to the intranet of UoA.

ΜΔΕ ΚΕΙΜΕΝΟ.τελικο 3.7.17.pdf
2 MB
File access is restricted only to the intranet of UoA.