Effectiveness of a new method of disinfecting the root canal, using Er, Cr:YSGG laser to kill Enterococcus faecalis in an infected tooth model.

Some lasers have demonstrated to provide effective disinfection when used as adjunctive device to the conventional treatment. The aim of this in vitro study was to determine the effectiveness of the erbium, chromium:yttrium scandium gallium garnet (Er, Cr:YSGG) laser by measuring its bactericidal effect inside the root canal experimentally colonized with Enterococcus faecalis. The laser was tested at different irradiation times (30 and 60 s) and energy of impulses (75 and 25 mJ). A total of 52 single-rooted extracted human teeth were endodontically prepared with rotary instrumentation. All were sterilized and inoculated with a suspension of E. faecalis (105 bacteria/ml). The teeth were randomized into three treatment (group 1, group 2, and group 3) and one control groups. In all groups, teeth were chemically irrigated with 5.25% sodium hypochlorite and 17% ethylenediaminetetraacetic acid. Groups 1 and 2 were also irradiated at 30 and 60 s, respectively, with an Er, Cr:YSGG laser at 75 mJ. Teeth of group 3 were treated with laser for 60 s at 25 mJ. Samples were processed to detect the presence of E. faecalis. For all groups, a bactericidal effect was observed. The use of laser at 75 mJ with an irradiation time of 30 and 60 s eliminated a percentage of 92.3 and 100% of E. faecalis, respectively. In the control group, a reduction of 92.3% was observed. Lower percentage of reduction (46.1%) was obtained in teeth treated with laser at 25 mJ for 60 s. No statistical differences were observed between the groups (P = 0.543, Fisher's exact test). The results indicated a bactericidal effect of Er, Cr:YSGG laser irradiation at the settings used in this study. The highest bactericidal effect of this laser was observed at 60 s of irradiation time, using an energy pulse of 75 mJ.

Attitudes of Italian dental and dental hygiene students toward tobacco-use cessation.

OBJECTIVE: The aim of this study was to investigate the smoking habits of Italian dental and dental hygiene students and to assess their knowledge on the health effects of cigarette smoking and their attitudes toward tobacco-use cessation (TUC) in dental practice. MATERIALS AND METHODS: Data was collected from 220 students attending the Dental and Dental Hygiene Schools (DS and DHS, respectively) at the University of Palermo (Italy). RESULTS: The percentage of smokers amongst DS and DHS students was similar (32.78% vs. 32.5%) with 67.77% of DS students and 77.5% of DHS agreeing that the damages to health caused by smoking were covered in their didactic course work. A high percentage of DS (63.33%) and DHS (67.5%) students reported the relationship between smoking and a number of associated health conditions. Both DS and DHS students showed poor knowledge of TUC interventions. Both DS and DHS students reported to be conscious of their own role as a counsellor, with DHS students feeling more comfortable in approaching counselling in clinical practice. Although DS and DHS students reported a positive attitude toward TUC interventions, almost half of the students had some concerns about the effectiveness of smoking cessation activities. DISCUSSION: The introduction of a comprehensive tobacco education curriculum in DS and DHS programs could further improve students' perceptions and attitudes and provide knowledge and clinical experience which would lead to the incorporation of TUC into subsequent professional practice.

Root resorption and orthodontic treatment. Review of the literature.

The aim of this paper was to provide a systematic review of the literature on the root resorption caused by orthodontic treatment. Original papers on this subject, published in English from January 2000 until December 2005, were located in the MEDLINE/PubMed database. Other sources were taken from the references of the selected papers. Root resorption is the most common sequela of the orthodontic treatment. It is an inflammatory process that leads to an ischemic necrosis localized in the periodontal ligament when the orthodontic force is applied. The onset and progression of root resorption are associated with risk factors related to the orthodontic treatment such as the duration of treatment, the magnitude of the force applied, the direction of the tooth movement, the method of force application (continuous versus intermittent), the orthodontic movement. Patient-related risk factors are the individual susceptibility on a genetic basis, some systemic diseases, anomalies in root morphology, dental trauma, and previous endodontic treatment. The prevention of root resorption during the orthodontic treatment may be performed controlling the risk factors. The periodic radiographic control during the treatment is necessary in order to detect the occurrence of root damages and quickly reassess the treatment goals.