Effects of treatment for manipulation of teeth and Er:YAG laser irradiation on dentin: a Raman spectroscopy analysis.

Biomedic Vibrational Spectroscopy Laboratory, Research and Development Institute, Universidade do Vale do Paraíba (UNIVAP), São José dos Campos, Brazil.
Photomedicine and Laser Surgery (Impact Factor: 1.67). 03/2007; 25(1):50-7. DOI: 10.1089/pho.2006.1020
Source: PubMed


The main purpose of this study was to evaluate the utility of Raman spectroscopy analysis as a research tool to study the effects of Er:YAG laser etching on dentin mineral and organic components. A secondary aim was to study the effects of the decontamination process and the storage procedure on dentin components.
There are no spectroscopy reports relating the effects of Er:YAG laser irradiation as an alternative to acid etching and the manipulation process on the dentin structure.
Twelve non-carious human third molars were divided in two main groups: stored in thymol solution (group A, n = 6) or autoclaved (group B, n = 6). The specimens were either etched with 37% phosphoric acid (control subgroup) or irradiated with Er:YAG laser. Irradiated samples were divided into the following subgroups: I, II, and III (80 mJ, 3 Hz, 30 sec; 120 mJ, 3 Hz, 30 sec; and 180 mJ, 3 Hz, 30 sec, respectively). Samples were analyzed by Raman spectroscopy.
The mineral and organic dentin contents were more affected in autoclaved teeth than in the specimens stored in thymol. Peak area reduction in group A specimens treated with phosphoric acid and pulse energy of 80 mJ were the most conservative surface treatments regarding changes in the peak area of organic and inorganic dentin components.
The autoclaving process and pulse energies of 120 and 180 mJ produced greater reduction of organic and inorganic contents in dentin, associated with greater reduction in the areas of 968, 1077, 1460, and 1670 cm(1) Raman peaks.

Download full-text


Available from: Luis Eduardo Silva Soares, Oct 05, 2015
13 Reads
    • "They also showed that this rate decreases for the extracted teeth in formalin in comparison to non-fixed specimens and this was significant.[16] This result is consistent with the findings of other studies.[817181920] Furthermore, formalin releases dangerous, and carcinogenic materials, which limit its application.[2122] "
    [Show abstract] [Hide abstract]
    ABSTRACT: Dental students use extracted human teeth to learn practical and technical skills before they enter the clinical environment. In the present research, knowledge, performance, and attitudes toward sterilization/disinfection methods of extracted human teeth were evaluated in a selected group of Iranian dental students. In this descriptive cross-sectional study the subjects consisted of fourth-, fifth- and sixth-year dental students. Data were collected by questionnaires and analyzed by Fisher's exact test and Chi-squared test using SPSS 11.5. In this study, 100 dental students participated. The average knowledge score was 15.9 ± 4.8. Based on the opinion of 81 students sodium hypochlorite was selected as suitable material for sterilization and 78 students believed that oven sterilization is a good way for the purpose. The average performance score was 4.1 ± 0.8, with 3.9 ± 1.7 and 4.3 ± 1.1 for males and females, respectively, with no significant differences between the two sexes. The maximum and minimum attitude scores were 60 and 25, with an average score of 53.1 ± 5.2. The results of this study indicated that knowledge, performance and attitude of dental students in relation to sterilization/disinfection methods of extracted human teeth were good. However, weaknesses were observed in relation to teaching and materials suitable for sterilization.
    Dental research journal 03/2013; 10(4):482-488.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study was to evaluate the effect of storage and disinfection methods (SDM) on bond strength (BS) to bovine dentin, using two adhesive systems: Adper Single Bond and Clearfil Protect Bond. Method: Extracted bovine teeth were assigned to the following SDM: 100% Humidity (HU); Gamma Radiation (GR); Autoclave (AU); 0.10g/mL Thymol (TH); 10% Formalin (FO); Frozen (FR); 0.2% Sodium Azide (SA) and 0.5% Chloramine T (CT) (n=10). The GR and AU groups were submitted to sterilization methods and stored at 100% humidity for 24 hours at 37C°, before testing. TH, FO, FR, SA and CT groups were stored for three months at 5C°, except for FR (-4C°). The adhesive systems were applied according to manufacturer’s instructions. For BS testing, the micro-shear test was performed, using Tygon mold (0.75mm diameter and 1mm high), which was filled with Clearfil AP-X (Kuraray) composite resin. Data were analyzed by two-way ANOVA and Tukey Test (p<0.05). BS of adhesive systems was similar for all SDM, except for 10% formalin. HU, GR, AU, TH and SA did not change the BS for the adhesives tested. For most of SDM, BS of adhesive systems was similar. Some 3 month-SDM groups (FR, FO and CT) reduced the BS.
    Brazilian Journal of Oral Sciences 11/2006; 6(22).
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The simultaneous need for infection-control protocols in sample preparations and for safe laser irradiation parameters prompted this study about the effects of heat produced by both sample sterilization and laser etching on dentin components. The dentin was exposed on 30 bovine incisors, and then divided into two main groups: autoclaved (group A) or thymol treatment (group B). The surface of the dentin was schematically divided into four areas, with each one corresponding to a treatment subgroup. The specimens were either etched with phosphoric acid (control-CG) or irradiated with Er:YAG laser (subgroups: I-80 mJ, II-120 mJ, and III-180 mJ). Elemental distribution maps were done by energy-dispersive X-ray fluorescence (μ-EDXRF) on each treatment area. The dentin surface in depth was exposed and line-scan maps were performed. The B_CG treatment produced the best distribution of calcium (Ca) and phosphorus (P) content throughout the dentin surface. Er:YAG laser etching produced irregular patterns of elemental distribution in the dentin. Laser energies of 120 and 180 mJ produced the highest maximum calcium values. The Er:YAG laser energy of 180 mJ produced a localized increase in Ca and P content on the superficial layer of the dentin (∼0–0.10 mm). The auto-claving treatment of samples in experiments is not recommended since it produced damaging effects on dentin components. Er:YAG laser irradiation produced a hetero-geneous Ca and P distribution throughout the dentin surface with areas of increased Ca concentration, and this may affect clinically the permeability, solubility, or adhesive characteristics of dental hard tissues with restorative procedures.
Show more