Biomedical subjects

Tayfun Alaçam

Publications and source records attributed to Tayfun Alaçam.

8 recordsLinked to original sources

PubMed2006

Evaluation of the smear layer removal effectiveness of EDTA using two techniques: an SEM study.

Obtaining the cleanest canal possible before obturation is one of the goals of endodontic treatment. The purpose of this study was to compare the smear layer removal capability of ethylenediamine tetra-acetic acid (EDTA) application with passive ultrasonic and cotton wrapped on reamer activation. Twelve extracted human teeth with single root canals were used for the study. They were conventionally hand instrumented using reamers and K files. The apical aspect of the canals was enlarged to a #40 file. The teeth were divided into 4 four groups, instrumented and irrigated as follows: Group-A EDTA agitated at the end of preparation with cotton wrapped on a reamer for 1 min; Group-B EDTA applied with ultrasonic agitation for 1 min; Group-C irrigated with EDTA+sodium hypochlorite (NaOCl) (negative control group); and Group-D irrigated with distilled water (positive control group). After scanning electron microscopic study at three different levels, smear layer and dentinal tubules were scored. Means were tested for significance using the Z test. When the techniques were compared, the cotton wrapped on reamer agitation method was as successful as the ultrasonic activation of the files. Although all groups had significantly higher smear layer scores at apical compared to coronal sections, no significant differences were recorded.

Chelating Agents↗

PubMed2006

Evaluation of antimicrobial and antifungal effects of iodoform-integrating gutta-percha.

OBJECTIVE: The antibacterial and antifungal effects of medicated gutta-percha (MGP) over different time periods have not been evaluated. The aim of this study was to evaluate and compare the antimicrobial and antifungal effectiveness of MGP and regular gutta-percha cones over different time periods using the disk diffusion method. METHODS: Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli were spread onto Mueller-Hinton agar, and Candida albicans was spread onto Sabouraud agar supplemented with glucose. Same-size MGP cones, conventional gutta-percha cones and disks impregnated with povidone-iodine were placed on the inoculated plates. The dishes were incubated at 37 degrees C aerobically. Growth inhibition zones were inspected and measured at 24, 48 and 72 hours. For each strain, experiments were performed in triplicate. The Kruskal-Wallis test was used to compare k independent samples. RESULTS: The disks impregnated with povidone-iodine inhibited all bacterial strains for up to 72 hours. No inhibition zones were seen around regular gutta-percha cones. MGP inhibited the growth of all bacteria over 24 hours, but in some cases these effects did not continue over longer periods. Specifically, the antimicrobial properties of MGP cones against E. coli and P. aeruginosa disappeared by 48 and 72 hours. Regardless of time and bacterial strain, MGP was statistically more effective than regular gutta-percha (p < 0.05). Povidone-iodine and MGP were effective against C. albicans for up to 72 hours, but regular gutta-percha exhibited no antifungal activity. CONCLUSION: The antimicrobial and antifungal characteristics of MGP may offer additional advantages over conventional gutta-percha.

Anti-Infective Agents, Local↗

PubMed2005

Microhardness of composites in simulated root canals cured with light transmitting posts and glass-fiber reinforced composite posts.

The aim of this study was to evaluate the depth of cure of composite resin cured within simulated root canals by means of light-transmitting plastic posts, glass-fiber-reinforced composite posts, and conventional light curing method. Thirty black plastic cylinders measuring 15 mm in length and 4 mm in internal diameter were divided into three groups. The composite resin was packed into simulated canals. The light-transmitting plastic posts and glass-fiber-reinforced composite posts were inserted into simulated canals and light cured for 90 seconds. The control group was light cured directly. To ensure continual change of material properties by increasing the length of material, a surface microhardness test was done 2 mm, 4 mm, 6 mm, 8 mm, 10 mm, 12 mm, and 14 mm from the light exposure surface. The results showed a significant increase in microhardness of composite resin (depth of cure) for both light-transmitting plastic posts and glass-fiber-reinforced composite posts compared with the control group. The microhardness of composite resin was also significantly higher with light-transmitting plastic posts than glass-fiber-reinforced composite posts after 8 mm.

Analysis of Variance↗

PubMed2004

Lateral perforation in parallel post space preparations.

This study evaluates the amount of remaining tooth structure and possibility of producing lateral perforation following the use of different diameters of parallel-sided Parapost drills in groups of different canal curvatures (0 degrees-15 degrees, 16 degrees-25 degrees, 26 degrees <) in distal canals of first and second mandibular molar teeth. After enlargement of root canals using the crown-down pressureless technique, Parapost drills #1, #2, and #3 were used in the different canal groups for the preparation of a post space. Standardized digital radiographs were taken before the post space preparation and after each Parapost drill application. Four horizontal lines (a, b, c, and d) were drawn at equal distances on these images, starting from the pulp chamber floor moving apically at 2 mm increments. There were no significant differences between the different curvature groups at the a, b, c, and d levels for the critical level of the remaining tooth structure (multiple comparison test; p>0.05). However, in considering root perforation, both at the inner and outer side of the roots, there were statistically significant differences at "c" and "d" levels in group 3 (#3 drill) without taking into account the root curvature (ANOVA; p< 0.5). None of the specimens showed strip perforation.

Dental Pulp Cavity↗

PubMed2004

Microhardness of packable composites used as posts condensed with different methods.

The purpose of this in vitro study was to evaluate the microhardness of packable composite compacted with hand or ultrasonic pluggers in post spaces. A total of 168 extracted human anterior teeth were prepared with Gates Glidden and ParaPost drills after obturation. A primer and a dentin-bonding agent were applied to the etched surface. Half of the specimens were compacted with an ultrasonic tip and the other half with a mechanical hand compactor and all specimens were polymerized for each increment. The roots were then sectioned horizontally from 0, 2.5, 3, 3.5, 4, 4.5, and 5 mm starting from the coronal and sliced 2.5-mm long. The microhardness test was applied to each specimen. There were statistically significant differences between ultrasonically and hand-condensed groups in whole specimens (p < 0.001). There were no significant differences between groups of 0, 2.5, and 3 mm until 3.5 mm was reached. After 3.5-mm depth, there were significant differences between the groups (p < 0.001). Ultrasonic condensation of packable composites provided mechanical advantage over hand condensation in root canals measuring microhardness in different depths. However, when microhardness was measured at different depths, values decreased after the depth of 3.5 mm in both condensation groups.

Acid Etching, Dental↗

PubMed2004

Substance P expression is elevated in inflamed human periradicular tissue.

Substance P is a neuropeptide believed to be a major mediator of neurogenic inflammation. The aim of our study was to evaluate whether substance P levels are elevated in the clinical biopsies collected from inflamed periradicular or control tissue. In this study, the presence of substance P was examined in infected human periradicular granulation tissue and control tissue. Sections from 19 periradicular granulomas and pulp tissues from two healthy control teeth were examined using the immunohistochemical method. Substance P-expressing neutrophils, macrophages, and plasma cells were found in both acute and chronic periradicular granulomas. In addition, we observed the presence of neutrophils expressing substance P without concurrent clinical symptoms of acute inflammation. Our results are consistent with the hypothesis that substance P may be released from neutrophils in the inflamed region, and thus, substance P may modulate clinical inflammatory response by release from either neuronal or immunocompetent cell populations.

Acute Disease↗

PubMed2002

Microleakage of packable composites used in post spaces condensed using different methods.

The aim of this in vitro study was to evaluate the apical and coronal microleakage of a packable composite material compacted by either hand or ultrasonic condensers when placed in post spaces. Forty-two extracted anterior teeth were used. After conventional obturation of the root canals, parallel post spaces 5 mm in depth and 2 mm in diameter were prepared using Gates Glidden and diamond burs. A primer and a dentin bonding agent (Prime & Bond NT) was applied to the etched surface for 30 seconds and light polymerized for 40 seconds. Surefil packable composite resin was inserted in four equal increments and each polymerized for 40 seconds. Half of the specimens were compacted with an ultrasonic tip and the other half with a mechanical hand compactor. After immersion in the dye, the teeth were sectioned longitudinally and dye penetration was evaluated using a stereomicroscope and microleakage recorded in mm. A One-Way Analysis of Variance indicated the two condensing methods were not statistically different (p>0.05). When microleakage was compared within groups, there was also no statistical difference between coronal or apical microleakage (p>0.05). In an in vitro environment, ultrasonic condensers do not offer any advantage over hand condensers. Both the coronal and apical portions of the root had microleakage indicating that regardless of the condensation method and the use of a packable composite, there is still microleakage that could potentially create further clinical problems.

Analysis of Variance↗

PubMed2002

Interappointment emergencies in teeth with necrotic pulps.

The incidence of interappointment emergencies in symptomatic and asymptomatic teeth with necrotic pulps was evaluated, and severity of flare-ups was determined by a quantitative method using a flare-up index. There were no significant differences in the incidence of flare-ups attributable to gender, age, diameter of lesion, taking analgesics, placebos, or no medication, or preoperative symptomatic or asymptomatic tooth diagnoses (p > 0.05). There were significantly more painful flare-ups in mandibular teeth than in maxillary (p < 0.05).

Adolescent↗