The effect of cisplatin-based chemotherapy on hearing loss (the frequency of >8 kHz) in children with cancer

INTRODUCTION

In this study we investigated the effect of cisplatin-based chemotherapy on hearing loss in children with cancer.

MATERIAL AND METHOD

In this retrospective study, 20 children aged 6 to 17 years with cancer who were treated with cisplatin and had normal results on initial audiometry test were included. The demographic, clinical, and medical information of all children was extracted and recorded. The hearing thresholds were determined for the frequency of >8 kHz by an audiometrist two weeks after receiving the last course of cisplatin. Finally, all data was analyzed.

RESULTS

In this study, 20 children with cancer were included of who 9 were girls (45 %) and 11 were boys (55 %). The patients' mean age at the time of diagnosis was 6.65 years. Results showed that children who received cisplatin ≥70 mg/m2 (P.value = 0.09) and ≥ 7 courses of cisplatin (P.value = 0.01), and a cumulative dose higher than 400 mg/m2 (P.value = 0.02) had higher chance of hearing loss.

CONCLUSION

According to the results it can be concluded that since higher doses caused higher risk of hearing loss and also since lower doses were effective for treatment of the cancer in children therefore to preventing the hearing loss, lower doses of cisplatin are recommended for cancer treatment in children.

The effect of vitamin B12 on idiopathic tinnitus

INTRODUCTION

Tinnitus is one of the most important challenges in the field of ear, nose and throat diseases. The aim of this study was to evaluate the effect of vitamin B12 on idiopathic tinnitus.

MATERIAL AND METHODS

In this double-blind clinical trial study, 140 patients with idiopathic tinnitus were divided into two groups, the group receiving vitamin B12 and the group receiving placebo. The first group received vitamin B12 for a month and the other group received placebo. All patients filled a THI questionnaire before the participation, one month and three months after the participation. VAS evaluation questionnaires were also filled for the patients before the participation, one month and three months after the participation. The effect of vitamin B12 on tinnitus was also assessed according to hearing loss status. The two groups were also compared regarding the side effects.

RESULTS

There was no significant differences between two groups regarding age (p.value = 0.523), gender (females (p.value = 0.810) and males (p.value = 0.789), and hearing loss status (p value = 0.651). According to VAS score, there was no significant statistical differences in tinnitus severity in each group (B12 group, p.value = 0.851 and placebo group, p.value = 0.386). There was no significant statistical differences in tinnitus severity based on VAS score between two groups before the participation (p.value = 0.560), one month (p.value = 0.485) and three months (p.value = 0.254) after the participation. According to THI criterion, there was no significant statistical differences in tinnitus severity in each group (B12 group, p.value = 0.259 and placebo group, p.value = 0.521). There was no significant statistical differences in tinnitus severity based on THI score between two groups before the participation (p.value = 0.651), one month (p.value = 0.125) and three months (p.value = 0.089) after the participation. None of the patients of the two groups had any noticeable side effects. The mean of VAS and THI also had no statistically significant difference before and after the intervention in term of hearing loss status (p.value>0.05). These results were not significantly different between the two groups in term of hearing loss status (p value>0.05).

CONCLUSION

The result of this study indicated that vitamin B12 has no distinctive effect on reducing tinnitus severity.

The effect of different concentrations and temperatures of sodium hypochlorite irrigation on pain intensity following endodontic treatment of mandibular molars with irreversible pulpitis: A randomized, double-blind clinical trial

OBJECTIVES

This study aimed to determine the severity of pain after endodontic treatment of mandibular molars with irreversible pulpitis following the use of sodium hypochlorite (NaOCl) at different temperatures and concentrations.

METHODS

In this randomized, controlled clinical trial, 72 patients with mandibular molars with irreversible pulpitis were randomly assigned to six groups. The teeth were anesthetized and the root canals were prepared. During the instrumentation, the root canals were irrigated with NaOCl solution at concentrations of 0.5% and 1% and temperatures of 2.5°C, 22°C, and 40°C, 2.5°C were achieved through cryotherapy. Assessment of pain was conducted before, immediately after, and 3, 24, 48, and 72 h after treatment. After obturation, the patients recorded their pain intensity at different time intervals on the visual analog scale (VAS) and reported the number of analgesics tablets they used. The frequency of analgesics tablets and their effect on pain sensation was recorded in the second part of the form. Repeated measures two-way analysis of variance test was used to compare the trend of pain changes over time between two intervals of time in each group. Friedman's nonparametric test was used to compare the intragroup mean score of pain over time and Kruskal-Wallis for comparing the intergroup mean score.

RESULTS

Changes in VAS pain scores of all the groups were significant over time (p < .001). Pain in all the groups decreased immediately after treatment and increased 3 h after treatment. There were no significant differences in pain ratings and the number of analgesics tablets used in the groups of NaOCl with different concentrations and temperatures over time.

CONCLUSIONS

Within the study's limitations, we concluded that there was no significant difference between concentrations of 0.5%, and 1% and temperatures of 2.5°C, 22°C, and 40°C in pain intensity following endodontic treatment of mandibular molars with irreversible pulpitis.

Comparison of the effect of NaOCL, curcumin, and EDTA on differentiation, proliferation, and adhesion of dental pulp stem cells

Introduction

This study examined the effect of 1.5% NaOCl, 17% EDTA, and curcumin on the proliferation, attachment, and differentiation of dental pulp stem cells (DPSCs) placed on the dentin specimens.

Methods

MTT assay was performed to evaluate the proliferation of DPSCs on the dentin specimens treated with different concentrations of NaOCl, 17% EDTA, and curcumin (0.97-250 μM). Cell-adhering ability of DPSCs was tested via the LDH assay to calculate the attached DPSCs. In addition, the western blotting assay was performed to investigate the expression levels of fibronectin as a cell-adhesion marker and analyze the expressions level of differentiation markers, including DMP-1, OCN, ALP, and DSPP, to detect the odontogenic potential of hDPCs.

Results

NaOCl had lower toxicity on DPSCs at lower concentrations (P < 0.001). The cytotoxicity of irrigants increased with increased dosage. The difference between the cell-adhesion ability of NaOCl and curcumin was not significant (∼4.4 MU/mL), whereas EDTA (∼3.8 MU/mL) exhibited the lowest release of LDH and less damage to hDPSCs. Regarding fibronectin expression, the pattern differed between irrigants in inducing cell adhesion. NaOCl increased fibronectin expression more than EDTA and curcumin. All the treated groups upregulated the expression of DSPP, DMP-1, OCN, and ALP compared to the control group, in which NaOCl showed a higher effect on the overexpression of differentiation markers.

Conclusion

The results showed that all the tested irrigants could be used in regenerative endodontic treatment. However, as an herbal-based and biocompatible irrigant, curcumin exhibited fewer adverse effects than NaOCl and EDTA.

The association between metabolic syndrome and the prognosis of idiopathic sudden sensorineural hearing loss

INTRODUCTION

In this study, we investigated the association between metabolic syndrome and the prognosis of idiopathic sudden sensorineural hearing loss.

METHODS

In this prospective cohort study, 79 patients with idiopathic SSNHL admitted to the ENT ward were involved. Patients were under treatment with two-dose pulse methylprednisolone and then oral corticosteroid (Prednisolone 1 mg/kg for up to 2 weeks and more). In all patients, the mean hearing threshold was measured before treatment and 3 weeks after the treatment. Metabolic syndrome criteria were assessed in all patients too. Then, based on these diagnostic criteria all data in patients with and without metabolic were compared.

RESULTS

There was a significant difference in Hypertension, BMI > 25, high TG and low HDL (p.v = 0.001) between two groups (metabolic syndrome group and non-metabolic syndrome group). The rate of recovered patients was significantly lower in the metabolic syndrome group than in the non-metabolic syndrome group (p.v = 0.001). It was found that metabolic syndrome (OR = 2.02), diabetes mellitus (OR = 7.32), HTN (OR = 4.09), BMI > 25 (OR = 3.24) and high initial hearing threshold (OR = 3.96) were clearly related to the poor prognosis of treatment.

CONCLUSIONS

According to the findings of this study, it was found that metabolic syndrome had a negative effect on hearing improvement in patients with idiopathic SSNHL.

Efficiency-Efficacy Assessment of External Lateral Osteotomy Technique Versus Internal One in the Rhinoplasty

In this study we aimed to compare external lateral osteotomy technique vs. internal one in the rhinoplasty. In this before-after clinical trial study 30 patients who were candidates for rhinoplasty involved. In each patient, external lateral osteotomy was performed on one side and internal lateral osteotomy was performed on the other side randomly. Information, including patients' age, sex, grade of edema and ecchymosis 1, 3, and 7 days after the surgery, and the type of lateral osteotomy, the amount of step deformity, the need for the specialist intervention, nasal bone mobility, and flail nasal bone was recorded and analyzed. The incidence of edema and ecchymosis on the first and the third day was statistically lower in the external method (P value < 0.001). Although the incidence of edema and ecchymosis on the seventh day was lower in the external method, it was not statistically significant (P value > 0.05). Forty seven percent of patients in the internal method and 36% of patients in the external method had step deformity (p value < 0.001). Fifty percent of patients in the internal method and 41% of patients in the external method needed the specialist intervention (p value > 0.05). Seventy four of patients in the internal method and 83% of patients in the external method had nasal bone mobility (p value > 0.05). Out of 30 patients, only one had flail nasal bone. Based on our findings, the external technique is suggested as a more effective and convenient method with less complications for inexperienced surgeons.

Investigating the possible association between thyroid nodule location and the malignancy risk of the nodules in FNA samples

INTRODUCTION

In this study we aimed to investigate the association between thyroid nodule location and the malignancy risk of the nodules in FNA samples.

METHODS

In this cross sectional study, 400 patients with thyroid nodule size >1.5 cm, thyroid nodule size >1 cm with micro-calcification, and thyroid nodule size <1 cm with sonographic or clinical signs of malignancy who referred to a training hospital, were involved. Morphologic characteristics of nodules, including nodule size, laterality and polarity were recorded. In patients with multinodular goiter, the anatomical location was recorded and analyzed.

RESULTS

In our study, 345 female patients (86.3 %) and 55 male patients (13.8 %) with thyroid nodule were involved. The majority of thyroid nodules were identified in the right lobe (n = 182, 45.5 %) and left lobe (n = 177, 44.3 %), respectively. A total of 323 nodules were benign and the remaining (n = 77) were malignant. The frequency of malignancy in the upper pole of the thyroid (31.6 %) was higher compared to that in the middle pole (10.7 %), lower pole (19.1 %), and isthmus region (26.8 %), leading to a significant difference (p.value = 0.001). The mean size of thyroid nodules was 15.68 mm in benign nodules and 20.08 mm in malignant nodules.

CONCLUSION

Our results showed that thyroid nodules found in the upper lobe carried the greatest risk for malignancy. Accordingly, it seems that the location of thyroid nodules can be an independent risk factor in determining the malignancy risk of thyroid nodules and can be used to enhance clinical decision making in thyroid FNA samples.

Papillary Thyroid Carcinoma with Nodular Fasciitis-Like Stroma in a 28-Year-Old Patient

Papillary thyroid carcinoma (PTC) is considered as a relatively common type of malignancy showing a wide morphologic spectrum. Different variants of this tumor have been reported. Among PTC variants, PTC with nodular fasciitis-like stroma (PTCFLS) is rare. This variant consists of stromal components rich in spindle cells and accounts for 60-80% of tumors. In addition, there are small foci of epithelial components in PTCFLS though its features are similar to conventional PTC. In this case study, we present a new case with PTCFLS. The case is a 28-year-old female who was referred to the ENT clinic due to a painless mass on the anterior part of her neck. The mass showed a gradual increase in size over the 6 months prior to her referral. Thyroid test results were normal. Ultrasound imaging demonstrated an 84 × 36 mm heterogeneous nodule in the right thyroid lobe without calcifications but increased vascularity. There were also some reactive lymph nodes in both sub-mandibular areas. An ultrasound-guided fine-needle aspiration (FNA) biopsy of the right thyroid lobe nodule revealed a benign thyroid adenomatoid nodule. Following right thyroid lobectomy, final pathologic studies confirmed a diagnosis of PTC with exuberant fibromatosis-like stroma. In the 20-day post-surgery visit, the patient was found asymptomatic. Re-evaluation of the left thyroid lobe and follow-up were recommended. In this study, a diagnosis of a rare variant of PTC, i.e., PTC-FLS, was made through a combination of ultrasonography, fine needle aspiration cytology, and histological examination.

BRAF Gene Mutation (V600E) in Aspiration Cytology of Patients With Suspected Papillary Thyroid Carcinoma

This study was attempted to investigate the prevalence of BRAF gene mutation (V600E) in aspiration cytology of patients with suspected papillary thyroid carcinoma (PTC). Seventy-six patients suspected of having PTC who were referred for fine-needle aspiration (FNA) biopsy were included in this cross-sectional study. Ultrasound-guided FNA was taken from the thyroid masses, and samples were sent for cytologic evaluation. Simultaneously, the samples were sent to a genetic laboratory to check the status of BRAFV600E mutation. Patients with FNA positive for PTC were assigned in one group, and those with FNA negative for PTC were assigned to another group. Cytological and molecular results were compared with those of histopathology and sonography. The results showed that the prevalence of the BRAF gene (V600E) mutation in our study was 21.1% (16 out of 76 patients). In addition, the results showed a significant relationship between gene mutation and pathologic findings so that the highest gene mutation was significantly detected in patients with FNA positive for PTC (P=0.001). Also, our results showed a significant relationship between gene mutation and some sonographic findings (calcification, P=0.004) and no significant relation in the other sonographic findings (hypoechoic changes, P=1.12 and regular changes, P=0.194). According to the results of the present study, BRAF mutation (V600E) can be an effective indicator for definitive diagnosis and primary treatment of PTC in suspected cases.

Ability of Calcium Silicate and Epoxy Resin-based Sealers to Fill the Artificial Lateral Canals in the Presence or Absence of Smear Layer

Background:The lateral canals are pathways for bacteria and their products to pass between the root canal and the periradicular tissue. Objectives: The present study aims to compare the filling ability of the lateral canals with three calcium silicate based sealers, including MTA Fillapex, Endoseal MTA and Sure-Seal Root, and AH26 epoxy resin sealer in the presence and absence of the smear layer. Materials and methods:Six lateral canals were prepared using an engine reamer in 80 single-rooted human teeth. The root canals were cleaned, then the teeth were randomly divided into two groups. In group A, the smearlayer was removed using 17% EDTA and 5.25% NaOCl, and in group B, the canals were irrigated with normal saline. Groups A and B were divided into four subgroups each, according to the sealer used: A1, B1 (MTA Fillapex sealer), A2, B2 (Endoseal MTA sealer), A3, B3 (Sure-Seal Root sealer), and A4, B4 (AH26 sealer). Obturation of canals was conducted by the warm vertical technique and then teeth were incubated for 72 hours. Teeth were made clear and the filling of lateral canals were evaluated under stereomicroscope. Results:In group A, the highest lateral canals filling rate was in subgroup A2 and the lowest in subgroup A1, and the difference was statistically significant. However, in both groups, the highest lateral canals filling rate was in subgroups B2 and B3 and the lowest in subgroup B1. However, the difference was not statistically significant. In addition, no significant difference was observed in the lateral canals filling rate considering their position in the root. Conclusion:Providing the removal of the smear layer, calcium silicate-based sealers, Endoseal MTA and Sure-Seal Root had a higher ability to fill the lateral canals than AH26 and MTA fillapex sealers.

Investigation of Serum Zinc Level in Patients with Hearing Loss and its Association with Tinnitus

Introduction: This study aims to determine the serum zinc level in patients with hearing loss and its relation with tinnitus.  Materials & Methods: In this Cross-Sectional study, 110 patients older than 20 years old with Complaining of hearing loss and tinnitus were involved. Participating patients were first visited by an ear, nose, and throat specialist with a history and physical examination, and were assessed for standard hearing loss as well as the intensity and frequency of tinnitus by standard audiometric tests. Then, fasting blood samples were taken to check serum zinc levels. Results:The mean serum level was 85.32 ± 27 27.62, and the mean frequency of tinnitus was 4.94 ± 2.76, both of which had significant differences between different groups (P = 0.001). The mean intensity of tinnitus was 7.77 ± 4.56, and there was no significant difference between different groups (P = 0.677). Serum zinc level and tinnitus frequency were associated with a correlation coefficient of 0.205 (P = 0.032), and serum zinc level and tinnitus severity were associated with a correlation coefficient of 0.249 (P = 0.009). Conclusion: According to the present study results, the positive effect of serum zinc levels on the severity and frequency of tinnitus has been determined so that with decreasing serum zinc levels, tinnitus occurs at lower frequencies.

Therapeutic Effect of Electrical Stimulation on Chronic Tinnitus: A Double Blind Randomized Controlled Trial

Chronic tinnitus is a disturbing condition that may affect different aspects of life. In this study, the therapeutic effect of electrical stimulation on chronic tinnitus was assessed. This was a clinical trial on 49 patients with persistent tinnitus for more than 6 months without a proper response to routine treatments. They were randomly allocated into two groups: the case group was treated with electrical stimulation for 6 sessions over 6 consecutive days, and the control group received a placebo. Before the intervention, one week and three months after the treatment sessions, patients were evaluated by comprehensive audiological assessments and hearing tests. The mean age of the participants was 40.37±9.32 and 41.35±9.24 in treatment and placebo groups, respectively. Tinnitus intensity was significantly decreased in the case group one week and three months after the treatment (P<0.05). Tinnitus handicap inventory score significantly decreased in the treatment group one week and three months after the treatment (P<0.05). There was no significant difference in tinnitus intensity after treatment, considering gender, age, tinnitus duration, and tinnitus type. Electrical stimulation could significantly reduce the severity of the tinnitus regardless of age, gender, duration, and type of tinnitus. © 2020 Tehran University of Medical Sciences. All rights reserved. Acta Med Iran 2020;58(1):4-8.

Cyclin D1 Expression in Patients with Laryngeal Squamous Cell Carcinoma

Background & Objective

Laryngeal squamous cell carcinoma (LSCC) is considered to be one of the most common cancers of the head and neck, accounting for roughly 90% of all malignant tumors of the larynx. To have a timely diagnosis for a better and practical therapy, molecular markers have to be investigated. The aim of this study was to determine the expression of Cyclin D1 (CD1) in patients with laryngeal squamous cell carcinoma.

Methods

In this study the demographic data of 82 patients with laryngeal squamous cell carcinoma, including age, gender and geographical region history of smoking and drug abuse, paraclinical findings, surgical description, and pathologic reports were extracted from their medical records. The stage and grade of the disease and tumor location were determined using their medical records. An appropriate tissue sample was selected. Then, the selected cancerous tissue samples stored as formalin-fixed paraffin-embedded tissue then were (Immunohistochemistry) IHC stained and analyzed in terms of the expression of CD1.

Results & Conclusion

According to the results, 75 out of 82 (91.5%) investigated samples were positive for CD1 expression. There was a significant relationship between stage of the disease (P=0.041) and CD1 expression in patients with laryngeal squamous cell carcinoma. There was no significant relationship between gender (P=0.055), age (P=0.256), history of smoking and drug abuse (P=0.192), location of the tumor (P=0.90), grade of the disease (P=0.515) and geographical region (P=0.466) and CD1 expression in patients with laryngeal squamous cell carcinoma. The results of the present study showed that CD1 expression was higher (91.5%) in patients with laryngeal squamous cell carcinoma in comparison to the other studies. According to the results we can conclude that stage of the disease can significantly affect CD1 expression in patients with squamous cell carcinoma.

The Effect of Gelfoam Impregnated With Botulinum Toxin on Allergic Rhinitis

INTRODUCTION

This study evaluated the effect of gelfoam impregnated with botulinum toxin on the symptoms induced by allergic rhinitis.

MATERIALS AND METHODS

In total, 30 patients with allergic rhinitis who did not respond to common therapies were included in this clinical trial study. All patients were treated with intranasal gelfoam impregnated with botulinum toxin type a (40 unit in each side) placed in the middle meatus of each nostril. The main symptoms of allergic rhinitis were scored from zero to three by the patients. Symptoms recorded and compared before and two months after the treatment.

RESULT

The mean age of patients was 31.03±6.9 years. The mean score for sneezing was 2.23 before the treatment which significantly decreased to 1.06 after the treatment (P<0.05). The mean scores of rhinorrhea, nasal congestion, and nasal itching were 2.53, 2.03, and 1.93, respectively, before the treatment which significantly decreased to 0.93, 1, and 0.8 after the treatment (P<0.05). No reported side effects was observed in this study.

CONCLUSION

According to the results, treatment with gelfoam impregnated with botulinum toxin is an effective and safe method in patients who have not responded to common therapies for allergic rhinitis. Accordingly, it is recommended to relieve symptoms in patients with seasonal allergic rhinitis in order to maintain the effectiveness of this treatment at least 8 weeks.

The Effects of Different Agitation Techniques of Canal Irrigant on Tubular Penetration of a Bioceramic Sealer

Introduction

This study aimed to compare the effects of different agitation techniques of sodium hypochlorite (NaOCL) as the final irrigation with XP-Finisher file, passive ultrasonic irrigation (PUI), Er:YAG laser and irrigation with conventional syringes, on penetration of Sure Seal Root bioceramic sealer into dentinal tubules.

Methods and Materials

Forty freshly extracted single-rooted human teeth were included in the present in vitro study. All the teeth were prepared up to #40 (4%) with Bio Race rotary file system, using crown-down technique. After chemomechanical preparation, the teeth were randomly assigned to 4 groups based on the agitation protocol: conventional needle irrigation (CNI) with a 30-G needle in a syringe, PUI, Er:YAG laser and XP-Finisher file, Subsequent to the agitation procedure, the root canals were obturated with tapered bioceramic-covered gutta-percha point and, bioceramic sealer, using the single-cone technique. The maximum penetration of the sealer into the dentinal tubules was determined in the coronal, middle and apical thirds using the scanning electron microscope (SEM) technique. After confirmation of the normal distribution of data with Shapiro-Wilk test, Data were analyzed using the one-way ANOVA and Tukey tests.

Results

The mean penetration depth of the bioceramic sealer into the dentinal tubules in the PUI group was greater than that of other groups; however, the difference between the two PUI and Er:YAG laser groups in the apical third was not significant (P=0.078). Er:YAG laser, PUI and XP-Finisher file agitation techniques resulted in significantly greater penetration of the bioceramic sealer into the dentinal tubules compared to the CNI (P<0.001). The XP-Finisher file technique in the apical (P=0.752) and middle thirds (P=0.339) and the Er:YAG laser technique in the apical thirds (P=0.086) were not significantly different from the conventional irrigation technique.

Conclusion

The PUI technique resulted in significantly deeper penetration of the Bioceramic sealer into the dentinal tubules compared to the three other techniques.

The relationship between endoscopic and radiologic findings and olfactory status of patients with chronic rhinosinusitis with nasal polyps before and after the endoscopic sinus surgery

INTRODUCTION

This study was attempted to investigate the relationship between radiologic and endoscopic findings and pre- and post-operative olfactory scores in chronic rhinosinusitis with nasal polyps.

MATERIALS AND METHODS

In this study, 40 patients aged 19-64 years with chronic rhinosinusitis with nasal polyps (CRSwNP) undergoing endoscopic sinus surgery were involved. The patients' olfactory status was evaluated using Smell Identification Test (Iran SIT) before and 3 months after the surgery. Patients' nasal endoscopic signs were recorded using Modified Lund-Kennedy scoring system before and 3 months after the surgery and radiological symptoms were recorded based on Lund-Mackay CT scoring before the surgery. Then the relationship between olfactory status and endoscopic and radiological findings was investigated.

RESULTS

With respect to mean of olfactory score, a significant difference was observed before and after the surgery (p value = 0.001). There was a significant difference between means of pre- and post-operative endoscopy scores (p value = 0.001). Pre-operative endoscopic and CT scan scores had a negative correlation with pre- and post-operative olfactory scores (p value < 0.05). Pre-op. olfactory scores had negative correlation with post-op. endoscopy scores (p value = 0.02). Post-op. olfactory scores had negative correlation with post-op. endoscopy scores but was not statistically significant (p value = 0.22).

CONCLUSION

Our results revealed that pre-operative endoscopy and radiology findings were consistent with the olfactory status of patients with CRSwNP before and after endoscopic sinus surgery.

Volume of Anesthetic Agents and IANB Success: A Systematic Review

The aim of this study was to provide an evidence-based answer to the question: "Is 3.6-mL volume of an anesthetic agent more effective than 1.8-mL volume in providing anesthesia for mandibular molars?" Following formulation of research question and keyword selection, a comprehensive search of the following databases was conducted: Cochrane library, PubMed, Scopus, Google Scholar, ProQuest, and Clinicaltrials.gov. Three-phase eligibility appraisal and quality assessment of the studies were carried out by 2 independent reviewers. To reduce clinical heterogeneity, the included studies were divided into 2 groups: studies on healthy teeth and studies on teeth with pulpitis. The data of included studies were statistically combined through meta-analysis using a fixed-effects model. A total of 20,778 records were initially retrieved from the search. Following screening and eligibility assessment, 8 studies met the eligibility criteria and were included for qualitative synthesis. Of those, 5 studies were qualified for meta-analysis. In the irreversible pulpitis group, increasing the volume of anesthetic agent from 1.8 to 3.6 mL significantly increased the success rate of inferior alveolar nerve block (risk ratio = 2.45, 95% CI: 1.67-3.59, p < .001). However, there was insufficient evidence to draw a conclusion regarding healthy teeth.

The Role of Immunological Factors on Sudden Sensoryneural Hearing Loss

INTRODUCTION

In this study, we examined the role of immunological factors on sudden sensory neural hearing loss (SSNHL).

MATERIALS AND METHODS

This prospective case-controlled study was performed in patients with SSNHL who referred to the ear, nose, and throat (ENT) ward. Fifty-six patients with SSNHLoccurring within a 72-hr period were selected as the case group and 56 participants who had no recent history of disease were assigned to the control group. Mean levels of immunological factors including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), antinuclear antibody (ANA), anti-neutrophil cytoplasmic antibody (ANCA) (C, P), anti-cyclic citrullinated peptide (anti-CCP), DSM, hemoglobin (Hb), complement component 3 (C3), and complement component 4 (C4) were evaluated in the blood samples in each group.

RESULTS

There were 31 male and 25 female participants in the control group, while the case group had 26 male and 30 female participants. The mean age of the participants was 36.2 ± 13.4 years in the control group and 40.80 ± 13.37 years in the case group. The two groups differed significantly in terms of mean ESR, ANA, C3, C4 and monocytes, with higher levels in the case group (P<0.05). However, differences in mean CRP, anti-Ds DNA, Hb, anti-CCP, white blood cells (WBC), neutrophils, lymphocytes, eosinophils, and platelets were not statistically significant between the case and control groups (P>0.05).

CONCLUSION

Because some of the immunological factors investigated in this study were significantly higher in patients with SSNHL, it can be concluded that there is an association between these immunological factors and SSNHL. Further studies are recommended to accurately determine the effect of these factors on the development of SSNHL and its treatment.

Smear layer removal evaluation of different protocol of Bio Race file and XP- endo Finisher file in corporation with EDTA 17% and NaOCl

Background

The aim of the present study was to compare the amount of the smear layer remaining in prepared root canals with different protocols of Bio RaCe files and XP-endo Finisher file (XPF) in association with 17% EDTA and sodium hypochlorite solution.

Material and Methods

A total of 68 extracted single-rooted teeth were randomly divided into 4 experimental groups (n=14) and two control groups (n=6). The root canals were prepared with Bio RaCe files (FKG Dentaire, Switzerland) using the crown-down technique based on manufacturer’s instructions and irrigated according to the following irrigation techniques: Group 1: XPF with 2 mL of 2.5% NaOCl for 1 minute. Group 2:, XPF with 1 mL of 17% EDTA for one minute. Group 3: XPF was used for 1 minute in association with normal saline solution. Group 4: XP-endo Finisher file for 30 seconds in association with 2.5% NaOCl and 17% EDTA for 30 seconds. The negative control group: NaOCl (2.5%) was used during root canal preparation, followed by irrigation with 17% EDTA at the end of root canal preparation. The positive control group: Normal saline solution was used for irrigation during root canal preparation. In all the groups, during preparation of the root canals with Bio RaCe file, 20 mL of 2.5% NaOCl was used for root canal irrigation and at the end of the procedural steps 20 mL of normal saline solution was used as a final irrigant. The samples were analyzed under SEM at ×1000‒2000 magnification and evaluated using Torabinejad scoring system. Data were analyzed with non-parametric Kruskal-Wallis test and post hoc Mann-Whitney U test, using SPSS. Statistical significant was defined at P<0.05.

Results

The results of the study showed the least amount of the smear layer at coronal, middle and apical thirds of the root canals in groups 2, which was not significantly different from the negative control group (P<0.5).

Conclusions

Under the limitations of the present study, use of a combination of NaOCl and EDTA in association with XPF exhibited the best efficacy for the removal of the smear layer.

Key words:Smear layer, XP-endo Finisher file, EDTA, Sodium hypochlorite.

Root Canal Morphologies of Mesiobuccal Roots of Maxillary Molars using Cone beam Computed Tomography and Periapical Radiographic Techniques in an Iranian Population

AIM

The aim of this study was to evaluate the accuracy of the results of cone beam computed tomography (CBCT) examinations, confirm the presence or absence of the second mesiobuccal (MB2) root canal in maxillary first and second molars, estimate the distance between the root canal orifices, observe the root types based on Vertucci classification system, and make comparisons between CBCT and periapical techniques in relation to the identification of the root canal form and the second root canal of the MB root.

MATERIALS AND METHODS

The CBCT and periapical radiographic data from the Department of Maxillofacial Radiology were used to select 156 individuals (78 females and 78 males) for the evaluation of the anatomy of maxillary first and second molars.

RESULTS

The prevalence rate of the second root canal in the MB root in the maxillary first molars was 55.1%, with 44.1 and 63.3% in females and males respectively. The prevalence rate in maxillary second molars was 23.7%, with 15.7 and 30.2% in females and males respectively. In addition, the longest and shortest distances between the root canal orifices were 2.4 and 0.3 mm respectively, with a mean of 1.3 mm.

CONCLUSION

There was a significant difference between the results of periapical and CBCT radiographic techniques in relation to the presence or absence of the second root canal in the MB roots of maxillary first and second molars (p < 0.01), with better results being provided by the CBCT technique.

CLINICAL SIGNIFICANCE

The results of CBCT images about the existence of the second root canal in the MB roots of maxillary first and second molars are more reliable, and we can use this technique in the finding of additional canals in the clinic. Keyword: Cone beam computed tomography, Dental radiography, Root canal therapy.

Comparing nasal packing with trans-septal suturing following septoplasty: a randomized clinical trial

It has been shown that nasal packing after septoplasty is associated with several complications. Our aim was to compare post-septoplasty nasal packing and trans-septal suturing, in terms of complications and outcome of operation. This randomized clinical trial was performed on patients with deviated nasal septum who were candidates for septoplasty. Patients were visited three times after operation (on the first 48 h, first week, and third post-operative month). Participants were checked for having common complications. Rhinomanometric evaluation was performed to measure nasal air flow and airway resistance, as indicators of operation efficacy, both prior to and after surgery. A total of 72 patients were allocated into the two trial arms. Patients in nasal pack group reported higher pain scores on the first 48 h (P < 0.001) and one week after surgery (P < 0.001). Epiphora (P = 0.028), sleep disturbance (P = 0.012), and dyspnea (P < 0.001) were also more commonly observed in patients using nasal pack. Objective evaluation of bleeding demonstrated that more severe bleeding occurred in patients with trans-septal sutures (P = 0.001). No differences were found comparing the indices of rhinomanometry between the two groups. Using trans-septal sutures after septoplasty compared to nasal packing, might be associated with lower frequencies of several specific complications and a lower rate of patients' discomfort. Nevertheless, increase in the risk of bleeding and hematoma was noted in the trans-septal suture group. No differences were observed between the nasal air flow and resistance of patients in the two groups.

Effects of Different Powder to liquid Ratios on the Push out Bond Strength of CEM Cement on Simulated Perforations in the Furcal Area

Background

Proper bond strength to dentin is one of the properties of biomaterials used for therapeutic purposes such as repair of furcal perforations. The aim of the present study to evaluate the effects of different powder to liquid ratios of Calcium-enriched mixture (CEM) on the push-out bond strengths in simulated perforations in the furcal area and compare it with Mineral trioxide aggregate (MTA).

Material and Methods

Furcal perforations, measuring 1.3 mm in diameter and 2 mm in height, were prepared in 120 mandibular first molars. Then the samples were randomly assigned to two groups (n=60). MTA and CEM cement were used for the repair of perforations in groups 1 and 2, respectively. Each group was divided into 3 subgroups based on the powder to liquid rations as follows: subgroup 1 (W/P) , 1:2; subgroup 2, 1:3; and subgroup 3, 1:4. After mixing and placing the materials in the perforation area, the samples were placed in closed containers at 37°C and 100% relative humidity for one week. A universal testing machine was used to determine the bond strength values. After recording the standard deviations, data were analyzed with two-way ANOVA. Statistical significance was set at P<0.05.

Results

In the MTA and CEM groups the highest push-out bond strength values were recorded in the third (W/P: 1:4) and first (W/P: 1:2) subgroups, respectively. There were significant differences in both groups between the ratios mentioned above and the other ratios (P<0.05).

Conclusions

Under the limitations of the present study, an increase in the powder-to-liquid ratio in CEM cement resulted in a decrease in bond strength, contrary to MTA.

Key words:CEM, Perforation, Powder-to-liquid ratio, push-out bond strength, MTA.

Accuracy of Working Length Determination using NovApex and Root-ZX Apex Locators: An in vitro Study

INTRODUCTION

This ex vivo study evaluated the accuracy of the Root-ZX electronic apex locator (EAL) (J. Morita, Tokyo, Japan) and the NovApex (Forum Technologies, Rishon Lezion, Israel) in determining the working length (WL) during endodontic treatment.

MATERIALS AND METHODS

Forty extracted single-rooted human teeth were selected for this study. The actual WL was measured with visual technique by a size #15 k-file under magnification. Then, the canal lengths were measured electronically with both Root-ZX and NovApex apex locators within ±0.5 and ±1 mm. Mean percentage of data was analyzed between groups using paired t-test, with a statistically significant level of p < 0.05.

RESULTS

The accuracy of NovApex apex locator was 85% within ±0.5 mm and 92.5% within ±1 mm. The accuracy of Root-ZX apex locator was 70% within ±0.5 mm and 97.5% within ±1 mm. There was no significant difference between the accuracy of the two EALs.

CONCLUSION

Both the NovApex and Root-ZX EALs are useful for measuring the WL with high accuracy.

CLINICAL SIGNIFICANCE

Given the importance of accurate WL determination in the success of endodontic treatments, the accuracy of different apex locators should be evaluated.

The Effect of Topical Tranexamic Acid on Bleeding Reduction during Functional Endoscopic Sinus Surgery

INTRODUCTION

Bleeding is a common concern during functional endoscopic sinus surgery (FESS) that can increase the risk of damage to adjacent vital elements by reducing the surgeon's field of view. This study aimed to explore the efficacy of topical tranexamic acid in reducing intraoperative bleeding.

MATERIALS AND METHODS

This double-blind, randomized clinical trial was conducted in 60 patients with chronic rhinosinusitis with polyposis (CRSwP) who underwent FESS. Patients were randomly divided into two groups; tranexamic or saline treatment. During surgery, normal saline (400 mL) or tranexamic acid (2 g) in normal saline with a total volume of 400 mL were used in the saline and tranexamic groups, respectively, for irrigation and suctioning. The surgeons' assessment of field of view during surgery and intraoperative blood loss were recorded.

RESULTS

Mean blood loss was 254.13 mL in the saline group and 235.6 mL in the tranexamic group (P=0.31). No statistically significant differences between the two groups were found in terms of other investigated variables, such as surgical field quality based on Boezzart's scale (P=0.30), surgeon satisfaction based on a Likert scale (P=0.54), or duration of surgery (P=0.22).

CONCLUSION

Use of tranexamic acid (2 g in 400 mL normal saline) through washing of the nasal mucosa during FESS did not significantly reduce blood loss or improve the surgical field of view. Further studies with larger sample sizes and higher drug concentrations, and using other methods of administration, such as spraying or applying pledgets soaked in tranexamic acid, are recommended.

Treatment of Necrotic Teeth Using Two Engine-Driven Systems and Patient's Postoperative Pain: A Double-Blind Clinical Trial

INTRODUCTION

One of the most important reasons for postoperative pain is the extrusion of debris from the apical foramen during preparation and shaping of root canals. The aim of this clinical trial was to evaluate the severity of postoperative pain with the use of two different engine-driven NiTi systems.

METHODS AND MATERIALS

Ninety mandibular molars were randomly divided into two groups (n=45), and root canal cleaning and shaping was done using either RaCe or Reciproc instruments. The severity of postoperative pain was determined with visual analogue scale (VAS) at 4-, 12-, 24-, 48- and 72 h and 1-week intervals and postoperative pain was compared between the two groups. The chi-squared test and repeated-measures analysis were used to compare the data between the two groups.

RESULTS

Based on the results of the statistical analyses, the two groups were matched regarding the age and gender, with no significant differences. In addition, except for 4- and 24-h and 1-week intervals, postoperative pain was significantly less in the RaCe group compared to the Reciproc group (P<0.001).

CONCLUSION

Based on the results of the present study, use of RaCe files for cleaning and shaping of root canals in necrotic mandibular molars resulted in less severe postoperative pain compared to Reciproc files.

Effect of Topical Anesthesia with Lidocaine-prilocaine (EMLA) Cream and Local Pressure on Pain during Infiltration Injection for Maxillary Canines: A Randomized Double-blind clinical trial

OBJECTIVES

This study compared the effect of local pressure and topical lidocaine-prilocaine (EMLA) cream on pain during infiltration injection for maxillary canine teeth.

MATERIALS AND METHODS

A total of 140 volunteer students participated in this split-mouth design randomized clinical trial. The subjects were randomly divided into four groups (n = 35). Before administration of anesthesia, in each group, one side was randomly selected as the experimental and the opposite side as the control. In group 1, finger pressure was applied on the alveolar mucosa on the experimental side and on the tooth crown on the control side. In group 2, 5% EMLA cream and placebo; in group 3, finger pressure and 5% EMLA cream; and in group 4, 5% EMLA cream and 20% benzocaine gel were applied. In all the groups, a buccal infiltration procedure was carried out. Pain during injection was recorded with visual analog scale (VAS). Wilcoxon and McNemar tests were used for statistical analysis of the results. Statistical significance was set at p < 0.05.

RESULTS

The results showed that EMLA reduced the injection pain significantly more than benzocaine (p = 0.02). Also, injection pain was significantly lower with the use of EMLA in comparison to placebo (p = 0.00). Application of local pressure reduced the injection pain, but the difference from the control side was not significant (p = 0.05). Furthermore, the difference between application of local pressure and EMLA was not statistically significant (p = 0.08).

CONCLUSION

Topical anesthesia of 5% EMLA was more effective than 20% benzocaine in reducing pain severity during infiltration injection. However, it was not significantly different in comparison to the application of local pressure.

Role of Platelet Parameters on Sudden Sensorineural Hearing Loss: A Case-Control Study in Iran

Sudden sensorineural hearing loss (SSNHL) is a common otological disorder characterized by a hearing loss greater than 30 dB over three consecutive frequencies, in less than 72 hours. It has been established that platelet parameters, such as mean platelet volume, are associated with ischemic heart events, whose clinical manifestations are similar to those of SSNHL. Hence, we aimed to determine if the platelet count, mean platelet volume and platelet distribution width are related to the occurrence and severity of sudden sensorineural hearing loss. A case-control prospective study was conducted in a teaching hospital in Iran. One hundred-eight patients with SSNHL and an equal number of healthy, age- and sex-matched controls were enrolled in the study. Peripheral venous blood samples were collected from the subjects, and the platelet count, mean platelet volume and platelet distribution width were measured with an automated blood cell counter. Analysis of the audiometry and hematological test results using SPSS22 software showed no statistical correlation between the platelet parameters and the occurrence of SSNHL, but correlation coefficients showed a significant correlation between PDW and hearing loss severity in patients group. However, further investigation is required to unequivocally establish the absence of correlation between the platelet parameters and occurrence of SSNHL.

Tissue Reaction and Biocompatibility of Implanted Mineral Trioxide Aggregate with Silver Nanoparticles in a Rat Model

Introduction:

Biocompatibility and antimicrobial activity of endodontic materials are of utmost importance. Considering the extensive applications of mineral trioxide aggregate (MTA) in dentistry and antimicrobial properties of silver nanoparticles, this study aimed to evaluate the subcutaneous inflammatory reaction of rat connective tissues to white MTA with and without nanosilver (NS) particles.

Methods and Materials:

Polyethylene tubes (1.1×8 mm) containing experimental materials (MTA and MTA+NS and empty control tubes) were implanted in subcutaneous tissues of seventy-five male rats. Animals were divided into five groups (n=15) according to the time of evaluation: group 1; after 7 days, group 2; after 15 days, group 3; after 30 days, group 4; after 60 days and group 5; after 90 days. The inflammatory reaction was graded and data was analyzed using the Kruskal-Wallis and Mann-Whitney U tests. Statistical significance was defined at 0.05.

Results:

Comparison of cumulative inflammatory reaction at all intervals revealed that the mean grade of inflammatory reaction to MTA, MTA+NS and control samples were 3, 2 and 2, respectively. According to the Mann-Whitney analysis there were no significant differences between MTA+NS and MTA (P=0.42).

Conclusion:

Incorporation of 1% nanosilver to MTA does not affect the inflammatory reaction of subcutaneous tissue in rat models.

The effect of protocol for disinfection of extracted teeth recommended by center for disease control (CDC) on microhardness of enamel and dentin

Background

According to the guideline of the United States center for disease control (CDC), the extracted teeth should be sterilized by autoclaving or storage in 10% formalin before using for educational or research purposes. The objective of this study was to evaluate the effect of this protocol on microhardness of dentin and enamel.

Material and Methods

Thirty extracted single-root teeth were used in this study. The crowns were resected, and the roots were longitudinally sectioned into two halves. The Vickers microhardness (VHN) of specimens was measured on polished canal dentin and buccal enamel surfaces. The crowns were randomly divided into three groups (n=10). Group 1 and 2 were sterilized using autoclave and formalin, respectively while group 3 (control) was stored in synthetic tissue fluid. The root halves were also randomly divided into 3 groups (n=20) which were treated as mentioned above for crown samples. Following sterilization, VHN of samples was measured again. ANOVA and paired samples t-tests were used to analyze the data.

Results

Autoclaving caused a significant reduction in microhardness of dentin (P <0.001, 12.04% decreases in VHN). However, there were no significant differences for before and after sterilization within other groups.

Conclusions

Based on the results of this study, the CDC protocol is recommended in studies related to enamel microhardness. However, Autoclaving is not an appropriate sterilization method in studies related to dentin microhardness. In these studies, two-week immersion in 10% formalin is recommended.

Key words:Autoclave, CDC, extracted teeth, formalin, microhardness, sterilization.

Antibacterial Effect of All-in-one Self-etch Adhesives on Enterococcus faecalis

Background and aims. The aim of this study was to evaluate the antibacterial activity of one-step self-etch adhesives on Enterococcus faecalis on days 1, 7 and 14 with the use of modified direct contact test.

Materials and methods. The modified directcontact test was used to evaluate the antibacterial effect of Adper Easy One, Bond Force, Clearfil S3 Bond, Futurabond M, G-Bond, iBond and OptiBond All-in-one adhesives on Enterococcus faecalis after aging the samples in phosphate-buffered saline for one, seven and fourteen days. Data were analyzed using one-way ANOVA and post hoc Tukey tests. Aging effect of each adhesive was evaluated by paired-sample test. In this study, P<0.05 was considered significant.

Results. All the tested adhesives exhibited antibacterial activity after one day and had significant differences with the positive control group (P<0.05). After one week, OptiBond All-in-one, iBond and Futurabond M exhibited significant differences in bacterial growth from other groups (P<0.05). There were no significant differences between the groups in two weeks (P>0.05).

Conclusion. iBond exhibited the highest antibacterial effect on E. faecalis after one week. Futurabond and OptiBond All-in-one exhibited antibacterial effects against E. faecalis for one week.

A scanning electron microscope study on the effect of an experimental irrigation solution on smear layer removal

INTRODUCTION

The aim of this in vitro study was to evaluate the effect of an experimental irrigation solution, containing two different concentrations of papain, Tween 80, 2% chlorhexidine and EDTA, on removal of the smear layer.

METHODS AND MATERIALS

Thirty-six single-rooted teeth were divided into two experimental groups (n=12) and two positive and negative control groups of six. The canals were prepared with BioRaCe instruments up to BR7 (60/0.02). In group 1, canals were irrigated with a combination of 1% papain, 17% EDTA, Tween 80 and 2% CHX; in group 2, canals were irrigated with a combination of 0.1% papain, 17% EDTA, Tween 80 and 2% CHX. In group 3 (the negative control), the canal was irrigated with 2.5% NaOCl during instrumentation and at the end of preparation with 1 mL of 17% EDTA was used; in group 4 (positive control), normal saline was used for irrigation. The amount of the remaining smear layer was quantified according to Hulsmann method using scanning electron microscopy (SEM). Data was analyzed by the Kruskal-Wallis and Mann-Whitney tests.

RESULTS

Two-by-two comparisons of the groups revealed no significant differences in terms of smear layer removal at different canal sections between the negative control group (standard regiment for smear layer removal) and 1% papain groups (P<0.05).

CONCLUSION

Under the limitations of the present study, combination of 1% papain, EDTA, 2% chlorhexidine and Tween 80 can effectively remove smear layer from canal walls.

Cone-Beam Computed Tomography Comparison of Canal Transportation after Preparation with BioRaCe and Mtwo Rotary Instruments and Hand K-Flexofiles

INTRODUCTION

The aim of this in vitro study was to evaluate the transportation of mesiobuccal canals of mandibular first molars prepared with either BioRaCe or Mtwo rotary instruments or hand K-Flexofile, by means of cone-beam computed tomography (CBCT).

METHODS AND MATERIALS

Forty-five mandibular molars were selected and randomly divided into three groups (n=15). Mesiobuccal roots of these teeth were prepared by BioRaCe, Mtwo, or hand K-Flexofile. Transportation was measured by pre- and post-operative CBCT images. Two-way ANOVA analysis was applied to detect any differences between the groups followed by the post hoc Tukey's tests. The level of significance was set at 0.05.

RESULTS

The non-parametric Friedman test was used to compare the behavior of each file at 3-, 6- and 9-mm levels. There were no significant differences between different levels in Mtwo group (P=0.15); however, the differences in K-Flexofile and BioRaCe groups were significant (P>0.05). The post hoc Tukey's test revealed significant differences between BioRaCe and K-Flexofile and also between Mtwo and K-Flexofile, both in the 3-mm depths (P<0.05).

CONCLUSION

Under the limitations of the present study, BioRaCe and Mtwo rotary instruments are considered suitable for canal preparation to greater apical sizes provided that the recommended sequences are observed.

Effect of smear layer on the push-out bond strength of two endodontic biomaterials to radicular dentin

INTRODUCTION

This in vitro study was designed to evaluate the effect of smear layer removal on push-out bond strength of white mineral trioxide aggregate (WMTA) and calcium-enriched mixture cement (CEM).

MATERIALS AND METHODS

Dentin discs with 3 mm thicknesses were divided into 4 groups (n=15): group 1: irrigation of the canal with normal saline and filling with WMTA; group 2: irrigation with sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA), and then filling with WMTA; group 3: same as group 1 but the lumens were filled with CEM; group 4: same as group 2 but the lumens filled with CEM. The samples were incubated at 37(°)C for 3 days after wrapping in gauze pieces moistened with distilled water. The push-out bond strengths were then measured by the universal testing machine and the failure modes were examined under a stereomicroscope at 40× magnification. Data were analyzed using two-way ANOVA and post-hoc Tukey's test for bond strength. Statistical significance was set at P<0.05.

RESULTS

The greatest and lowest mean standard deviation for push-out bond strength were observed for groups 4 (3.13±1.46 MPa) and group3 (1.44±0.96 MPa), respectively. The effect of smear layer removal on push-out bond strength of CEM was significant (P=0.01), however, it was not significant for WMTA (P=0.52). The failure mode for all the groups was of mixed type.

CONCLUSION

Under the limitations of this study, smear layer removal is recommended for CEM in order to gain higher push-out strength.

Effect of Mineral Trioxide Aggregate, Calcium-Enriched Mixture Cement and Mineral Trioxide Aggregate with Disodium Hydrogen Phosphate on BMP-2 Production

INTRODUCTION

One of the hypotheses regarding the calcification induction by mineral trioxide aggregate (MTA) is the involvement of transforming growth factor-Beta (TGF-β) super family. Calcium-enriched mixture (CEM) cement is one of the endodontic biomaterials with clinical applications similar to MTA. The aim of the present in vitro study was to compare the induction of bone morphogenic protein-2 (BMP-2) by a combination of disodium hydrogen phosphate (DSHP) and tooth colored ProRoot MTA (WMTA), to that of CEM cement and WMTA.

METHODS AND MATERIALS

Human gingival fibroblasts (HGFs) were obtained from the attached gingiva of human premolars. HGFs were cultured in Dulbecco's Modified Eagle's medium, supplemented with 10% fetal calf serum, penicillin, and streptomycin. Cells in groups 1, 2 and 3 were exposed to WMTA, CEM and WMTA+DSHP discs, respectively. The fourth group served as the control. After 72 h of exposure, HGF viability was determined by Mosmann's tetrazolium toxicity (MTT) assay. BMP-2 levels in cell-free culture media were determined by enzyme-linked immunosorbent assay (ELISA). Statistical analysis was performed using the one-way ANOVA, followed by the post hoc Games-Howell test for BMP-2 and post hoc Tukey's test for the results of MTT assay.

RESULTS

Cellular viability was significantly higher in group 3 compared to the other groups (P<0.05); however, CEM and WMTA did not exhibit significant differences (P=0.08). The control group exhibited significantly higher cellular viability in comparison to the other groups of the study (P<0.05). The highest and lowest protein production rates were observed in the WMTA (3167±274.46 pg/mL) and WMTA+DSHP (1796±839.49 pg/mL) groups, respectively. There were no significant differences between the control, WMTA and CEM groups (P>0.05).

CONCLUSION

WMTA and CEM did not exhibit any significant differences in terms of inducing BMP-2 production; however, incorporation of DSHP into WMTA resulted in a decrease in the induction of this protein.

Antimicrobial efficacy of photodynamic therapy and sodium hypochlorite on monoculture biofilms of Enterococcus faecalis at different stages of development

BACKGROUND AND OBJECTIVE

As the Enterococcus faecalis biofilm ages, it is likely that bacteria in mature and old biofilms will become more resistant to commonly used antibacterial irrigants. Photodynamic therapy (PDT) has been used to kill resistant bacteria organized in a biofilm. This study aimed to investigate the antimicrobial effectiveness of 1% sodium hypochlorite (NaOCl), 2.5% NaOCl, and PDT on E. faecalis biofilm at different stages of development.

METHODS

In this study 4-, 6-, and 8-week-old E. faecalis biofilms were subjected to one of the following approaches: phosphate-buffered saline solution (PBS), PDT, or 1% and 2.5% NaOCl. Dentin chip suspensions were used for colony forming units (CFU) counting to estimate remaining E. faecalis counts.

RESULTS

PDT and 2.5% NaOCl completely eliminated E. faecalis biofilms in three stages of biofilm development, whereas 1% NaOCl resulted in 81.88%, 85.73%, and 78.62% reductions of bacterial counts in 4-, 6-, and 8-week-old biofilms, respectively, which was significantly more than PBS.

CONCLUSIONS

The bacteria in mature and old biofilms were more resistant to 1% NaOCl than were the bacteria in young biofilms. Overall survival and residual bacteria increase with biofilm aging. PDT and the 2.5% NaOCl solution were equally efficient in completely eliminating E. faecalis biofilms at all three stages.

Managing a mandibular second premolar with three-canal and taurodontism: a case report

Root canal anatomy diversity and aberrations are common especially in permanent dentition. A thorough understanding of the basic root canal anatomy and its diversities are necessary for successful endodontic treatment. Mandibular second premolars are usually single-rooted and have one root canal. Incidence of three separate root canals in this tooth is quite rare and taurodontism with three separate canals has never been reported in literature so far. The use of cone-beam computed tomography scan in this rare case greatly contributed to making a confirmatory diagnosis and successful nonsurgical endodontic management thereafter.

Effect of Duration of Irrigation with Sodium Hypochlorite in Clinical Protocol of MTAD on Removal of Smear Layer and Creating Dentinal Erosion

Background and aims

The aim of the present study was to compare 1.3% sodium hypochlorite (NaOCl) in MTAD (mixture of tetracycline isomer, acid, and detergent) for the removal of the smear layer and induction of canal erosion.

Materials and methods

38 maxillary incisors were divided in three experimental groups of 10 and two positive and negative control groups of each 4 teeth, and prepared using rotary files. In test groups, 1.3% NaOCl was used for 5, 10 and 20 minutes during preparation followed by MTAD as the final rinse. In negative control group, 5.25% NaOCl was used for 10 minutes followed by 17% Ethylenediamine Tetra-Acetic Acid (EDTA) as the final rinse. In positive control group, dis-tilled water was used for 10 minutes during preparation and then as the final rinse. The samples were examined under scan-ning electron microscope, and the smear layer and dentinal erosion scores were recorded.

Results

Five and 10 min groups had significant differences with 20 min group (p < 0.05). In apical third, 5 and 10 min groups had also significant differences with 20 min (p < 0.05). In the coronal thirds, when the time of irrigation with 1.3% NaOCl increased from 5 min to 20 min, erosion also increased significantly. However, 5 and 10 min groups had no signifi-cant differences with negative control group.

Conclusion

The use of 1.3% sodium hypochlorite for 5 and 10 minutes in the MTAD protocol removes the smear layer in the coronal and middle thirds but does not induce erosion.

Effect of Synthetic Tissue Fluid on Microleakage of Grey and White Mineral Trioxide Aggregate as Root-End Filling Materials: An in vitro study

OBJECTIVES

The success of endodontic surgery has been shown to depend partly on the apical seal. Grey mineral trioxide aggregate (GMTA) produces hydroxyapatite twice as often as white mineral trioxide aggregate (WMTA) when suspended in a phosphate buffered saline (PBS) solution. The aim of this in vitro study was to compare the microleakage phenomenon of gray and white mineral trioxide aggregates as root-end filling materials after immersion in synthetic tissue fluid (STF).

METHODS

55 single-rooted extracted maxillary anterior human teeth were divided into two experimental groups of 20 teeth each, plus 3 groups of 5 teeth each as two negative and one positive control groups. The root canals were cleaned, shaped, and laterally compacted with gutta-percha. The root ends were resected and 3 mm deep cavities were prepared. The root-end preparations were filled with GMTA or WMTA in the experimental groups. Leakage was determined using a dye penetration method. Data were analysed using analysis of variance (ANOVA) at the 0.05 level of significance.

RESULTS

The mean dye leakage was 0.40 ± 0.1 mm for GMTA and 0.50±0.1 mm for WMTA groups, respectively. There was no significant difference between the two experimental groups (P = 0.14).

CONCLUSION

Despite the different properties and behaviours of GMTA and WMTA in STF, there were no significant differences in microleakage when using GMTA or WMTA.

Efficacy of different concentrations of sodium hypochlorite and chlorhexidine in disinfection of contaminated Resilon cones

OBJECTIVES

The aim of this study was to evaluate the effectiveness of different concentrations of Chlorhexidine (CHX) and sodium hypochlorite (NaOCl) in disinfecting contaminated Resilon cones within one minute.

STUDY DESIGN

Fifty Resilon cones were divided into seven experimental groups and three control groups of 5 cones each. The cones of experimental groups were contaminated with E. faecalis and subsequently disinfected with different concentrations of NaOCl or CHX. The cones were then transferred into glass tubes containing thioglycollate media and incubated for 7 days. The tubes were examined for turbidity every 24 hours, and if bacterial growth occurred, samples were plated, incubated, gram stained and observed under microscope to confirm E. faecalis growth. Negative, positive, and washing control groups were also used.

RESULTS

All the positive and washing control showed profound E.faecalis growth. All the cones disinfected with CHX showed bacterial growth; however, no E. faecalis growth occurred in any samples disinfected with NaOCl.

CONCLUSION

Sodium hypochlorite, at concentrations of 0.5 to 5.25%, is an effective agent for disinfection of contaminated Resilon cones within one minute; however, chlorhexidine is unable to disinfect Resilon cones during one-minute exposure.

Comparison of two histopathologic methods for evaluating subcutaneous reaction to mineral trioxide aggregate

Objectives: One of the most important factors for suitable materials for pulp therapy is biocompatibility. Two histopathologic methods of Cox and Federation Dentaire International (FDI) were used to evaluate inflammation. In Cox method, density of inflammatory cells, tissue reactions like fibrosis, vascular responses like congestion and fibrin extravasation have been used to evaluate inflammatory reactions. The aim of this study was to compare the accuracy of pathologists’ interpretations using two different methods. Study design: Three pathologists observed the degree of inflammation in 225 histopathologic sections. These sections showed inflammation in subcutaneous connective tissue of rats adjacent to polyethylene tubes, filled with white or gray mineral trioxide aggregate. Empty tubes served as controls. Samples were harvested after 7-, 15-, 30-, 60-, and 90-days. All pathologists examined the sections under a light microscope (Carl Zeiss, Oberkochen, Germany) at ×400 magnifications. Chi-Square test was used to evaluate the difference between inflammation grades when one pathologist used two methods. Cohen’s Kappa value was used to measure agreement of three pathologists to recognize the degrees of inflammations when using one of the methods. Results: There were no significant differences between the two methods when one of the pathologist used these methods to report the degree of inflammation (p=0.054). However, two other pathologists reported significant differences between two methods (p=0.005, p=0.001). In the FDI method, there was an acceptable agreement between first and second, and first and third pathologist in terms of the degree of inflammation, and intermediate agreement existed between the second and third pathologist. With the Cox method, no agreement among the pathologists could be found. Conclusion: The results of three pathologists in terms of rating inflammation with the FDI method showed better agreement than with the Cox method. Therefore, FDI method is more reliable than the Cox method to evaluate inflammation.

Key words: Biocompatibility, connective tissue, infammation, mineral trioxide aggregate.

Effect of alkaline ph on sealing ability of white mineral trioxide aggregate

OBJECTIVES

The aim of this study was to evaluate microleakage of white mineral trioxide aggregate (WMTA) after its exposure to a range of alkaline environments during hydration.

STUDY DESIGN

Seventy single-rooted teeth were divided into 4 experimental and 2 control groups. All the teeth were instrumented, and their apices were resected. Root-end cavities were filled with WMTA in the experimental groups. In the control groups, root-end cavities were not filled. Root-end fillings were exposed to alkaline environments with pH values of 7.4, 8.4, 9.4, or 10.4 for 3 days. Microleakage was evaluated by bovine serum albumin. Evaluations were carried out at 24-hour intervals for 80 days. Data were analyzed by one-way analysis of variance and a post hoc Tukey test at the 0.05 level of confidence.

RESULTS

The number of days (mean ± standard deviation) needed for color change at pH values of 7.4, 8.4, 9.4, and 10.4 were 78.53 ± 5.68, 80.00 ± 0.00, 68.93 ± 19.00, and 34.46 ± 12.73, respectively. The time needed for leakage to occur was significantly shorter in samples stored at a pH value of 10.4 (P<0.001).

CONCLUSIONS

Within the limits of this study, it can be concluded that pH values greater than 9.4 may jeopardize the sealing ability of WMTA during hydration.

Microleakage comparison of glass-ionomer and white mineral trioxide aggregate used as a coronal barrier in nonvital bleaching

OBJECTIVES

There is some evidence that the pH at the root surface is reduced by intracoronal placement of bleaching pastes, which is known to enhance osteoclastic activity. Therefore, it is recommended that a protective barrier be used over the canal filling to prevent leakage of bleaching agents. Glass-ionomer (GI) is commonly used as a coronal barrier before nonvital bleaching. Because mineral trioxide aggregate (MTA) creates high alkalinity after mixing with water, using MTA as a protective barrier over the canal filling may not only prevent leakage of bleaching agents and microorganisms, but may prevent cervical resorption. The aim of this study was to evaluate sealing ability of white mineral trioxide aggregate (WMTA) as a coronal barrier before nonvital bleaching.

STUDY DESIGN

Root canals of one hundred thirty human maxillary incisors were instrumented and filled with gutta-percha without sealer. Gutta-percha was removed up to 3 mm below the cementoenamel junction (CEJ). The teeth were randomly divided into six experimental groups of 20 teeth each and two control groups of 5. In three experimental groups, WMTA was packed into the canal to the level of CEJ. In the remaining experimental groups, glass-ionomer (GI) was used as a coronal barrier. After a 24-hour incubation period, one of the following three bleaching agents was placed in the access cavity of each of the WMTA or GI groups. These three bleaching agents were 30% hydrogen peroxide, sodium perborate mixed with 30% hydrogen peroxide, and sodium perborate mixed with distilled water. The bleaching agents were replaced every 3 days for three times. In the positive controls, no coronal barrier was used. In the negative controls, all the tooth surfaces were covered by two layers of nail varnish. Microleakage was evaluated using protein leakage test. Statistical analyses were performed with the Kruskal-Wallis and Mann-Whitney tests.

RESULTS

The experimental groups showed minimum leakage which was not significantly more than tha in the negative controls. There was no statistically significant difference in leakage between the experimental groups (p<0.05).

CONCLUSIONS

This study indicated that different bleaching agents have no effect on sealing ability of WMTA.

Primary angiosarcoma of the thyroid gland in an young Iranian woman

Angiosarcoma of the thyroid gland is a rare and aggressive primary malignant tumour of the thyroid, originally reported in patient from Swiss Alpine region. Here, the authors describe a case of primary angiosarcoma of the thyroid in an 21-year-old Iranian woman who presented with a rapidly enlarging neck mass associated with compressive symptoms.

Mandibular second premolars with three root canals: a review and 3 case reports

Before initiating any endodontic therapy, probability of extra canals should be considered. The Incidence of three canals in mandibular second premolar has been reported to be 0.46-0.5%. The present report describes nonsurgical endodontic treatment of three mandibular second premolars with three canals. In these cases, three orifices were located in mesiobuccal, distobuccal and lingual. Mesiobuccal orifices were found after removing dentinal shelves. Even in teeth with extremely complex root canal morphologies, conventional endodontic treatment without surgical intervention can result in adequate healing, as in these cases. Clinicians should be aware of unusual root canal anatomy in mandibular premolars. Very careful examination of the pulpal space, preferably with an optical device is recommended to locate any unusual orifices.

Endodontic treatment of a hypertaurodont mandibular second molar: a case report

A 28-year old patient was referred for endodontic treatment of his left mandibular second molar. The patient had no history of systemic diseases and his chief complaint was spontaneous pain in left posterior region of mandible. Clinically, there was a deep caries in the left mandibular second molar. Radiographic examination of this tooth revealed a long crown containing large pulp chamber and two short roots with a apically located furcation, indicating hypertaurodontism. After coronal access preparation, five orifices were found including mesiolingual, mesiobuccal, distobuccal, mid-distal and distolingual. Subsequent to root canal preparation, a modified filling technique was used for canal obturation. After one year the treated tooth was symptom free.

A mandibular second premolar with three canals and atypical orifices

Mandibular second premolars with three canals (Type V, Vertucci) and separate foramina are very rare. The anatomy of the pulp chamber floor in these premolars usually reveals one lingual and two buccal orifices at the same level. This case report describes a second premolar with three canals and an unusual pulpal floor anatomy with one distobuccal and one distolingual orifice at the same level and an orifice on the mesiolingual wall. Very careful examination of the pulpal space, preferably with an optical device, is recommended to locate any unusual orifices.

Root canal configuration and the prevalence of C-shaped canals in mandibular second molars in an Iranian population

A total of 139 extracted mandibular second molars were injected with India ink and demineralized. They were made clear and transparent with methyl salicylate, and the anatomy of their canals was studied. It was found that 86.3% of mandibular second molars had two roots, 9.3% had one root, and 4.3% had three roots. Ninety percent of the mesial roots of the mandibular second molars with two roots had two canals (predominantly with a type II or III configuration), and 77.5% of the distal roots of these teeth had one canal (predominantly with a type I configuration). Among the mandibular second molars, 7.2% had C-shaped canals and these configurations were seen mostly in single-rooted mandibular second molars. The results of this study indicate that mandibular second molar teeth have many variations in the number of roots and the morphology of their canals. Therefore it should not be assumed that all mandibular second molar teeth have two roots and three canals.