Excimer laser coronary angioplasty in acute myocardial infarction

We evaluated the short-term results of percutaneous excimer laser angioplasty in acute myocardial infarction. Of the 18 patients studied, 2 were female and 16 male with a mean age of 56.6 +/- 12.1 years. Thrombolysis in myocardial infarction grades 0, 1, and 2 flow was observed in 10, 5, and 3 cases, respectively, prior to the procedure. The degree of stenosis was 97.9% +/- 5.1%. The lesion was crossed with a laser catheter in all cases, using a mean number of 808 +/- 384 laser pulses. Type C dissection developed in only 1 case (6%). Except for this case, distal flow was grade 3 in all the patients. Following the procedure, ST segment resolution exceeding 70% was achieved in 14 cases (78%) within the first 90 minutes. The success rate of laser ablation was 94% (17 patients). Stent implantation was performed in all the cases. In conclusion, laser angioplasty is an effective and reliable treatment for acute myocardial infarction.     

Fracture resistance of roots filled with three different obturation techniques

Objectives: The aim of this study was to compare in vitro root fracture resistance following root canal filling with AH 26 using lateral condensation, BeeFill, and Thermafil techniques. Study Design: Eighty extracted human mandibular premolars with similar dimensions were selected. In order to standardize the roots, measurements were taken in two separate regions of the teeth—at the cemento-enamel junction and 8 mm apically from the junction—buccolingual as well as mesiodistal for every tooth. Teeth were then randomly divided into five groups (n=16). With the exception of the non-prepared group (Group 1), instrumentation was done in all groups. In group 2, instrumentation but no filling was performed; in group 3, the obturation was done with AH 26 + gutta-percha; in group 4, with AH 26 + BeeFill and in group 5, AH 26 + a Thermafil obturator was used. All the roots were mounted vertically in copper rings and filled with acrylic resin, exposing 8 mm of the coronal part. A universal testing machine was used for the strength test. Results: The results were analyzed using the one-way ANOVA test. The significance between the groups was tested with Temhane’s T2 test. The results indicate that instrumentation of root canals had a significant effect on fracture resistance (p<0.05). In addition, there were no differences between the root canal obturation techniques; furthermore, these techniques did not create a statistically important resistance to vertical fracture (p>0.05). Conclusions: The results suggest that instrumentation of root canals significantly weakens the tooth structure to fracture and the root canal obturation techniques that are used are not able to form reinforcement. Key words:AH 26, obturation technique, vertical fracture.     

Effect of Agitation of EDTA with 808-Nanometer Diode Laser on Removal of Smear Layer

Introduction

Near-infrared diode lasers can be used for several applications, which range from disinfection to smear layer removal in endodontics. This study evaluated the efficacy of agitation of 15% EDTA with an 808-nm diode laser on removal of the smear layer.

Methods

Sixty extracted human maxillary central incisor teeth were instrumented up to ProTaper F4 (Dentsply Maillefer, Ballagues, Switzerland) and then randomly divided into 6 groups (n = 10 for each group) according to the different final irrigating protocols as follows: 5% sodium hypochlorite for 120 seconds performed with the NaviTip (Dentsply Maillefer, Ballaigues, Switzerland) (control group); 15% EDTA for 120 seconds performed with the NaviTip; and agitation of 15% EDTA with an 808-nm diode laser for 10, 20, 30, and 40 seconds. Specimens were observed under a scanning electron microscope, and open dentinal tubules were counted using Adobe Photoshop software (Adobe Systems, San Jose, CA). The data were analyzed with 1-way analysis of variance and Tukey post hoc tests (P = .05).

Results

The number of open dentinal tubules was higher in the middle thirds than in the apical thirds. The differences between the apical and middle thirds were statistically significant (P < .05). Statistically significant differences were also found between the control group and the other groups in both the middle and apical thirds of the root canals (P < .05).

Conclusions

The results indicated that agitation of 15% EDTA with an 808-nm diode laser for 20 seconds was effective in removing the smear layer in the apical thirds of root canals.     

Influence of Ankaferd Blood Stopper on shear bond strength of bonding systems

This study investigated the effect of Ankaferd Blood Stopper (ABS) contamination on bond strength of total- and self-etching systems. Seventy mandibular third molars sectioned in a mesio-distal direction were mounted in acrylic resin, and flat dentin surfaces were exposed. The specimens were randomly assigned to seven groups (n=20), according to the surface treatment: Group I, ABS contamination+37% phosphoric acid+Solobond M; Group II, ABS contamination+Clearfil SE Bond; Group III, ABS contamination+All Bond SE; Group VI, 37% phosphoric acid+ABS contamination+Solobond M; Group V, Solobond M; Group VI, Clearfil SE Bond; and Group VII, All Bond SE. Next, a resin composite (Grandio) was built up using a plastic apparatus and polymerized. The specimens were tested in shear mode at a crosshead speed of 1 mm/min. There were significant differences in bond strengths between the control and ABS-contaminated samples. These findings suggest that ABS contamination reduced bond strength of total- and self-etching adhesives.