Comparison of the force required to fracture roots vertically after ultrasonic and Masserann removal of broken instruments.

AIM: To evaluate the force required to fracture roots vertically after the removal of broken instruments using ultrasonic tips and a Masserann kit. METHODOLOGY: Thirty-nine extracted human anterior teeth with single and straight roots were used. The crown of each tooth was removed until the full length of the tooth was 13 mm. All canals were instrumented with the step-back technique to a size 25 K-file. The teeth were randomly divided into three groups: two experimental groups and a control group. The size 30 K-files used for the test were notched to a depth of half of the instrument with a No. 2 round bur at a point 3 mm from the tip to facilitate breakage of the file at this point. The fractured instruments were removed from the canals using ultrasonic tips or a Masserann kit. The samples were subjected to a continual vertical loading, using a universal testing machine. For each root, the force at the time of fracture was recorded in Newtons. The results were analysed statistically using one-way anova and Tukey HSD test. RESULTS: The force required to fracture the roots vertically was significantly higher in the control group than the experimental groups (P < 0.01). The roots from which the broken instruments had been removed using ultrasonic tips required more force to fracture than roots in the Masserann group; however, the difference was not statistically significant. CONCLUSION: Removal of a fractured instrument from the middle third of the root decreased the force required to fracture the root vertically, regardless of the technique used for instrument removal. There was not difference between the ultrasonic technique and the Masserann technique.

Cytotoxicity of 5 endodontic sealers on L929 cell line and human dental pulp cells.

AIM: To investigate the cytotoxicity of five root canal sealers on L929 mouse fibroblasts and primary human dental pulp cells. METHODOLOGY: Cylindrical specimens of AH Plus (Dentsply De Trey GmbH, Konstanz, Germany), RoekoSeal (Coltène Whaledent, Langenau, Germany), EndoREZ (Ultradent Products Inc., South Jordan, UT, USA), Epiphany (Pentron Clinical Technologies, LLCC, Wallingford, CT, USA) and Activ GP (Brasseller Inc., USA, Savannah, GA, USA) were kept at 37 °C in a humidified atmosphere of 5% CO(2) for thrice the length of the setting time given by the manufacturer. Extraction of specimens was performed after setting in cell growth medium for 1, 4 and 7 days. Undiluted, 50% and 25% diluted eluates were incubated with cultured cells for 24 and 72 h. Cytotoxicity was assessed using MTS colorimetric bioassay. Kruskal-Wallis test and post hoc Dunn's multiple comparison test were used to compare the sealers and diluted/undiluted eluates in terms of cell viability (% of control). Friedman test and post hoc Dunn's multiple comparison test were performed to compare extraction periods. Wilcoxon test was utilized in comparing 24- and 72-h readings. RESULTS: Undiluted 1-day eluate of Activ GP was significantly more cytotoxic than all other sealers (P < 0.0001). Undiluted 4- and 7-day eluates of Epiphany and Activ GP were significantly more cytotoxic than the other three sealers (P < 0.0001). Diluted eluates of Activ GP and Epiphany were generally less toxic than the undiluted ones. The cytotoxicity of Epiphany significantly increased as the extraction period increased (P < 0.0001). Epiphany became more toxic with time of exposure to cells. No or minimal cytotoxicity was observed with RoekoSeal, AH Plus and EndoREZ. CONCLUSIONS: The sealers exhibited varying degrees of cytotoxicity dependent on their chemical composition.

Resin composite restorations of permanent incisors with crown fractures: a case report with a six-year follow-up.

Using resin composite for the restoration of permanent incisors that have crown fractures is a conservative, timely and economical treatment option. Presented in this case report is a 41-year old female patient with resin composite restorations of anterior teeth that had crown fractures. This manuscript presents the clinical success of these resin composite restorations of permanent incisors after six-years.

Fracture resistance of roots using different canal filling systems.

AIM: To evaluate the fracture resistance of teeth filled with various canal filling materials. METHODOLOGY: The crowns of 100 single-rooted teeth were removed leaving 12 mm of the roots. The canals were shaped using Endo-Sequence files. Following instrumentation, 80 teeth were divided into four groups. The remaining 20 teeth were divided into two groups. The teeth in each group were filled as follows: Group 1: AH-Plus + Gutta-percha (Cold lateral compaction), Group 2: Resilon + Epiphany (Cold lateral compaction), Group 3: ActiV GP cone + ActiV GP sealer, Group 4: ActiV GP sealer + Gutta-percha (Cold lateral compaction), Group 5: No instrumentation or filling, Group 6: Instrumentation but no filling. After the sealers had set, the roots were embedded in acrylic moulds and subjected to a compressive loading at a rate of 1 mm min(-1). The load at which fracture occurred was recorded and statistically analysed using Kruskal-Wallis one-way analysis of variance and Z-tests. RESULTS: The fracture values of the experimental teeth were significantly higher than those of the instrumented but unfilled group (P < 0.05). Teeth in the AH-Plus + lateral compaction group had higher fracture resistance compared with the ActiV GP sealer + Gutta-percha group (P < 0.05). CONCLUSIONS: Systems aiming to obtain a monoblock system were not superior to the conventional AH-Plus + Gutta-percha technique in terms of fracture resistance. The fracture resistance of roots using ActiV GP + lateral compaction Gutta-percha was significantly reduced compared with the AH-Plus + Gutta-percha group.

Incidence of the type and calcification patterns in patients with elongated styloid process.

We investigated the incidence of elongated styloid process (Eagle's syndrome) using panoramic radiographs taken of 860 patients referred to our clinic. Any styloid process identified was classified according to its length, type and the pattern of calcification. Fifty-nine elongated styloid processes were identified in 32 patients (3.7%), most being bilateral; 24 patients were female and eight were male (female/male ratio: 3:1). The mean age of these patients was 43 +/- 14 years (range: 18 - 78 years). Type I (elongated) was the most frequent type on both sides (42/59); and the most frequent patterns of calcification were partially calcified on the left side (18/59) and completely calcified on the right side (16/59). Only two patients were symptomatic. A corrected differential diagnosis is important to distinguish elongated styloid process from other pathologies with partially overlapping symptoms. We would recommend that clinicians consider the possibility of Eagle's syndrome when both the clinical and radiographic evidence support this diagnosis.

Reliability and validity of the Modified Dental Anxiety Scale in Turkish patients.

We aimed to determine dental anxiety among Turkish patients and assess the sensitivity, specificity, positive/negative predictive values and reliability of the Modified Dental Anxiety Scale (MDAS) and Corah's Dental Anxiety Scale (DAS). Patients referred to our clinic for dental treatment who had a history of dental anxiety were included in the study. 294 randomly selected patients (mean age 38.8 years) completed a questionnaire combining Corah's DAS and MDAS. They were retested 15 days later. The prevalence of dental anxiety was found to be 9.9% (29/294) for Corah's DAS at the cut-off point > or = 15 and 8.8% (26/294) for the MDAS at the cut-off point > or = 19. Both dental anxiety scales gave acceptable sensitivity, specificity, positive and negative predictive values at these cut-off points.

Factors affecting apical leakage assessment.

This study was conducted to evaluate the influence of immediate versus delayed immersion time, and passive dye immersion versus centrifuged dye on apical leakage measurements. Eighty-four extracted human teeth with single straight canals were instrumented and divided into four experimental groups of 20 teeth each plus 2 negative and 2 positive controls. Low-temperature injection thermoplasticized gutta-percha and sealer were used to obturate the root canals. In groups A and B the filling materials were allowed to set for 72 h before the teeth were placed in India ink. In groups C and D the teeth were placed in India ink immediately after obturation. Also, in groups B and D the teeth were centrifuged in India ink for 20 min at 3,000 rpm before being immersed in ink. After 72 h in India ink, the teeth were cleared, and the linear extent of ink penetration was measured with a stereomicroscope. Statistical analysis of the data revealed no significant difference in leakage among the experimental groups whether the teeth were immersed in ink immediately after obturation or after setting of the filling materials for 72 h, and whether or not the teeth were centrifuged in ink prior to immersion.

Cytotoxic and mutagenic potencies of various root canal filling materials in eukaryotic and prokaryotic cells in vitro.

Cytotoxic and mutagenic effects of root canal filling cements of various chemical composition were determined in vitro. Materials set for 24 h and 1 wk were eluted for 24 h in cell culture medium (cytotoxicity testing) and dimethyl sulfoxide or physiological saline (mutagenicity testing). The differences between cytotoxic potencies of eluates of the endodontic materials on L-929 cells were quantified colorimetrically (MTT test). Eluates of Traitement SPAD were about 5- to 30-fold more toxic than silver-free AH26, Tubli-Seal, CRCS, and Endomethsone N. The rank order of the toxic effects depended on the setting time of mixed materials. Dimethyl sulfoxide and saline eluates of Traitement SPAD, Tubli-Seal, Endomethasone N, CRCS, and Ketac-Endo were not mutagenic in the Ames test. Both eluates of silver-free AH26 set for 24 h were weakly mutagenic in Salmonella typhimurium TA100. Weak mutagenicity of saline eluates of the material was also observed in TA97a and TA102. These results point to the possibility that mixed silver-free AH26 might contain small amounts of two mutagenic substances: bisphenol A diglycidyl ether and formaldehyde.

Periodontal condition in Turkish recruits.

The periodontal condition of 300 Turkish troops was investigated using the modified Ramfjord Periodontal Disease Index. In addition, the gingival condition, presence and quantity of plaque and calculus, location and depth of periodontal pockets, tooth mobility, presence and severity of wear facets, diastema magnitude and the DMFT Index were determined. The average PDI was 3.8. Nearly 98% of the recruits suffered from gingivitis, 68% of whom exhibited moderate to severe inflammation without involvement of deeper structures. Moderate plaque accumulation and heavy calculus deposits were observed. An average DMFT of 5.09 was found. Little correlation was found between the relatively low DMFT rate and the Plaque Index.

Detection of jaw and root fractures using cone beam computed tomography: a case report.

The aim of this case report is to demonstrate jaw and root fractures using a combination of cone beam CT (CBCT), CT and conventional radiographs. In this presentation a 23-year-old female patient who was referred to our dental clinic with a severe facial trauma is reported. The patient was initially examined by a general dentist and a fracture in the mandibular right canine region was diagnosed on the CT images. Once referred to our clinic, the raw CT images were re-evaluated by three maxillofacial radiologists in the Oral Diagnosis and Radiology Department. Two new fracture lines that were not reported on the original CT analysis were diagnosed among the raw CT images. More detailed information was obtained about dentoalveolar fractures with CBCT compared with CT and conventional radiography.

Cross-sectional evaluation of the periapical status and quality of root canal treatment in a selected population of urban Turkish adults.

AIM: To investigate the prevalence of apical periodontitis and the quality of root canal treatment in an adult Turkish population who visited a university dental clinic. SUMMARY: The periapical status of 8863 teeth belonging to 375 patients was evaluated by two pre-calibrated observers from panoramic radiographs. The presence of apical periodontitis, and the prevalence and quality of root fillings were recorded. The relationship between the radiographic quality of root fillings and apical periodontitis was examined by chi-squared statistical-analysis. Of 8863 teeth, 470 (5.3%) had undergone root canal treatment. Forty-seven per cent of all the subjects had at least one root-filled tooth. Periapical radiolucencies were visible on 4.2% of teeth examined, with 53.5% of root-filled teeth presenting apical periodontitis. Ninety-one per cent of root-filled teeth with periapical pathosis were determined to have inadequate root fillings. A statistically significant correlation was found between the quality of root fillings and the presence of apical periodontitis (P < 0.05). KEY LEARNING POINTS: The radiographic quality of root fillings correlated with periapical radiographic signs of pathosis in a selected population of Turkish adults. There is a need to improve the standards of root canal treatment in the study population.

Delayed type allergic reaction following the use of nonlatex rubber dam during endodontic treatment.

AIM: To describe the development of a delayed type allergic reaction 24 h following the use of nonlatex rubber dam during endodontic treatment. The symptoms were alleviated with adequate medication; however, the patient rejected any further analysis. SUMMARY: In recent years, allergic reactions because of latex rubber dam and gloves have received more attention. Nonlatex products are advocated in clinical use in cases where the patient presents an allergic background. Although rare, adverse reactions may be encountered even with these products. In this article, a very rare case is presented in which a patient developed signs of allergy 24 h after the utilization of nonlatex rubber dam and gloves during endodontic treatment. Signs including visible redness on the mucosa, submucosal oedema and desquamation in the vestibular mucosa were observed. With proper medication, the signs and symptoms were alleviated. Although the patient was referred to an allergy specialist for patch testing, she did not accept any further analysis. KEY LEARNING POINTS: This case emphasizes the necessity of precautions during the management of latex-allergic patients in clinical practice. The unusual response encountered in this patient does not undermine the usefulness of nonlatex rubber dam and gloves in sensitive individuals.

Survey of dental radiological practice in Turkey.

OBJECTIVES: The aim of this study was to determine the dentist's knowledge about dose reduction techniques, radiographic equipment and quality of dental radiographic service in general dental practice in Turkey. METHODS: The survey was performed on 636 dentists who attended the 11th International Congress organized by the Turkish Dental Association. Information on the demographic characteristics of the dentists, radiographic equipment, techniques and processing they used and radiation protection was obtained with a 32 point questionnaire. RESULTS: The respondents' knowledge concerning the technical details of their equipment was limited, with 512 (86.9%) not knowing the kilovoltage peak (kVp) of their machine. Only 34 (5.5%) respondents reported having rectangular collimators. The dentists had little knowledge about the speed of film they used. D-speed film was the most preferred one with 21.6%. Fifty-eight (10.2%) dentists used E-speed film and the F-speed film was used only by 13 (2.3%) dentists. The most preferred technique (62%) for periapical radiography was the bisecting angle technique. Four hundred and eighty five (82.5%) of the dentists reported that they took the radiographs by themselves. CONCLUSIONS: In the present study, the results indicate that for minimizing any unnecessary radiation, attempts should be made to improve dentists' knowledge about radiation dose reduction techniques.

An apical leakage study in the presence and absence of the smear layer.

The apical seal produced by low-temperature injection of gutta-percha, with or without root canal sealer, in the presence or absence of the smear layer was evaluated quantitatively using an electrochemical technique. The root canals of 44 teeth were prepared with the smear layer intact following a final flush of NaOCl (group 1), while the root canals of a further 44 teeth were prepared and the smear layer removed with a final flush with EDTA followed by NaOCl (group 2). Subgroups were obturated using Ultrafil System alone or accompanied by Calciobiotic Root Canal Sealer. Microleakage data was expressed as a percentage of apical leakage evident in each group. Statistical analysis of the results revealed that the groups obturated with Ultrafil alone showed no significant differences in leakage compared with the groups where sealer was used, either when the smear layer had been left intact or removed. (P > 0.05). However, comparison of the combined two groups with smear layer present versus the combined two groups with smear layer removed showed a highly significant difference (P < 0.01), with the incidence of leakage reduced in the absence of the smear layer.