Comparison of the Enterococcus faecalis Colony Reduction Effect of Two Wavelengths of Diode Lasers With Three Methods of Root Canal Irrigation: An In Vitro Study.

Introduction: The basis of successful root canal therapy is the reduction of microorganisms. The aim of this in vitro study was to compare the antibacterial effect of three different irrigation methods with two laser wavelengths on Enterococcus faecalis biofilm. Methods: Ninety-five single-canal teeth were prepared, sterilized, and divided randomly into a negative control, a positive control, and five test groups. They were inoculated with the standard strain of E. faecalis. The test groups were conventional irrigation (group 1), Passive ultrasonic irrigation (group 2), Gentle file finisher brush (group 3), 810 nm diode laser (group 4), and 980 nm diode laser (group 5). Microbial sampling, cultivation, and colony counting were done. Data were analyzed with the Kruskal-Wallis test and a negative binomial regression model. Results: There was a significant difference in the colony count between the groups (P<0.001). the 810 nm diode had the highest and the conventional irrigation group had the lowest reduction in the microbial load. Passive ultrasonic, 980 nm diode laser, and Gentle file finisher brush groups were also ranked respectively from the highest to the lowest in terms of decreasing effect on the number of colonies. Conclusion: The 810 nm diode laser and conventional irrigation were respectively the most and the least effective methods for reducing the number of E. faecalis colonies.

Comparison between three methods of diode laser 810 nm, photodynamic therapy with laser 660 nm, and hypochlorite solution for disinfection of pulp canal of primary teeth.

Background: The presence of treatment-resistant microorganisms is known as the main cause of pulpectomy failure in the endodontic treatment of deciduous teeth. The usage of lasers can contribute to reducing these microorganisms. This study aimed to compare the effect of three disinfection methods for deciduous teeth canals using laser diode 810 nm, photodynamic therapy with laser 660 nm and methylene blue, and sodium hypochlorite. Materials and Methods: In this experimental study, 58 single-root deciduous teeth with no root resorption were investigated in four groups, including one control group of 10 and three intervention groups of 16. Preparation of the samples was done using manual files up to three numbers after the initial file. After sterilizing the samples in an autoclave, Enterococcus faecalis bacteria were cultured in the canals. In the first group, irrigating with hypochlorite 2.5% was done; in the second group, photodynamic therapy was performed using a laser diode and 0.1 mg/mL methylene solution; and in the third group, high-intensity laser 810 nm direct radiation was done into the canal. Next, samples were taken from all canals. The colony formation unit (CFU) of the bacteria was counted in the blood agar culture medium. The data were analyzed using Kruskal-Wallis and negative binomial regression test (α =0.05). Results: The mean CFU differed significantly between the four groups. The rate of incidence of E. faecalis colonies showed a reduction in all three intervention groups compared to the negative control. In the high-intensity laser 810 nm group, there was 68.4%; in the photodynamic therapy with diode 660 nm and methylene blue, there was 88%; and in the hypochlorite group, 98.3% reduction was observed compared to the negative control group. Conclusion: Based on the results of this study, to compare three disinfection methods of the deciduous teeth canals without preparation of canals, sodium hypochlorite had greater efficiency. All three groups of laser, photodynamic therapy, and sodium hypochlorite showed reductions of E. faecalis bacterial colony compared to the control group. The reductive effects of CFU were greater in the hypochlorite sodium group, followed by photodynamic and direct laser radiation groups.

Laser Excisional Biopsy of Bleeding Tumor near Newly Erupted Tooth in an 11-Month-Old Patient under General Anesthesia.

Pyogenic granuloma (PG) is a well-known tumor-like growth that commonly appears in the gingiva of the oral cavity. This reactive lesion can develop in response to local irritation, chronic low-grade trauma, long-term low-grade infection, or hormonal imbalances. PG is more frequently observed in individuals during their second and third decades of life, although it can occur at any age. It is more prevalent in young females than males, but on rare occasions, it can be found in children, even infants. Several treatment options exist for PG lesions, which apply after a final diagnosis specified by biopsy and histopathological investigations. Surgical excision is the most common treatment choice for PG lesions. However, comparisons between laser therapy and surgical excision have shown numerous advantages for laser treatment, making it a preferred option for soft tissue lesions. Laser excision offers benefits such as precise and deep incisions, preservation of sterile conditions, improved hemostasis, avoidance of sutures, and less invasive procedures resulting in reduced intra- and postoperative discomfort, pain, and bleeding. This report is aimed at presenting a case of an 11-month-old infant with a gradually growing pyogenic granuloma (PG) lesion that appeared in the palate behind the upper left first deciduous tooth, with a duration of approximately 2 months. The parents reported a history of bleeding associated with the lesion, which emerged after the eruption of the mandibular tooth. An excisional biopsy was done by the application of an 810 nm diode laser under general anesthesia, and the specimen was evaluated by a pathologist. No posttreatment complications or relapses were observed in this case.

In vitro comparative effects of laser photodynamic therapy with methylene blue or aminolevulinic acid on oral squamous cell carcinoma cell line.

Background: This study aimed to compare the effects of laser photodynamic therapy (PDT) with methylene blue (MB) or aminolevulinic acid (ALA) on the oral squamous cell carcinoma (OSCC) cell line. Materials and Methods: In this in vitro experimental study, the C152 (KB) OSCC cell line was cultured in a culture medium containing 10% fetal bovine serum. The cells were exposed to 0.1, 0.2, 0.5, 1, 2, 5, and 10 mM concentrations of MB and ALA alone and combined with diode laser irradiation with 660 nm wavelength, 40 mW power, and 10 J/cm2 energy density in continuous-wave mode perpendicular to the surface. Cell viability was assessed using the methyl thiazolyl tetrazolium assay and compared among the groups by the Kruskal-Wallis test. Results: The results showed that the reduction in cell viability in the MB + laser and ALA + laser groups was greater than that in the MB and ALA groups without laser (P < 0.001). Significant differences were noted in cell viability in the presence of some different concentrations of MB and ALA (P < 0.05), such that by an increase in their concentration, cell viability decreased. Cell viability in the MB + laser group was significantly lower than that in the ALA + laser group in some photosensitizer concentrations (P < 0.05). Conclusion: Within the limitations of this in vitro study, the results showed that laser PDT with MB (high concentrations) was more effective than laser PDT with ALA against the OSCC cell line.

The Diagnosis and Treatment of a Rare Maxillary Plasmacytoma: a Case Report.

The jaw plasmacytoma is a very rare condition, which its diagnosis is difficult in clinical routine. Up to now, less than 60 cases of jaw plasmacytoma have been reported in the literature. In the present case report, we reported a rare case of jaw plasmacytoma in a 42-year-old female, which was misdiagnosed with dental granuloma and abscess. The diagnosis of plasmacytoma was done by immunohistochemistry (IHC) evaluation following a cone beam computed tomography (CBCT) assessment. The patient was treated with radiotherapy and is disease free after 2 years.

Relationship between the elongated styloid process in panoramic radiographs and some of the general health conditions in patients over 40 years of age in the Iranian population.

BACKGROUND: The styloid process and the attached ligaments have the potential for calcification and ossification in specific conditions. The purpose of this study was to evaluate the relationship between the elongated styloid process (ESP) frequency and some of the systemic health factors of patients over 40 years of age. MATERIALS AND METHODS: In this analytical-descriptive study, 296 panoramic radiographs of patients over 40 years of age (165 female and 131 male) referred to the Dental School of Khorasgan Azad University were selected. The length of the styloid process was measured by a special ruler and recorded in a questionnaire form. Other data such as sex, age, height, weight, blood pressure, heartbeat and the number of teeth present in the mouth were also recorded. The lengths equal to or more than 30 mm on the radiographs were considered as ESP. Data analysis were done by independent t-test, Pearson correlation coefficient and Chi-square test at a significance level of < 0.05. RESULTS: ESP was observed in 135 cases (45.6%). There was a significant relationship between ESP and the body height, weight and the blood pressure, but there was no significant correlation between ESP, the heartbeat and the number of teeth present in the mouth. CONCLUSION: Because of the significant relationship between the length of the styloid process and the blood pressure, height and weight it is reasonable to evaluate a patient's systemic health conditions when radiographic signs of ESP are observed.

Trends in oral cancer rates in Isfahan, Iran during 1991-2010.

BACKGROUND: There is a variation in trends of oral cancers all over the world. Many investigations have reported evidence of an increasing incidence in oral cancers during recent years. The purpose of this study was to investigate time trend and changes in demographic distribution of oral cancers incidence in Isfahan during 1991-2010. MATERIALS AND METHODS: In this retrospective analytic study archive of Oral Pathology Department of School of Dentistry, Isfahan University of Medical Sciences from 1991 to 2010 were reviewed. A total of 231 Pathology reports were analyzed. Age, sex, primary site, histologic type of cancer, and the referral year were recorded. Data were analyzed by using Jointpoint Regression Program 3 and SPSS 18. P value less than 0.05 consider as significant level. RESULTS: Out of all malignancies, 55% were male and 45% were female. The most frequent cancer was squamous cell carcinoma. Comparing the two time intervals (1991-2000) and (2001-2010) showed that the ratio of carcinomas and salivary gland tumors had decreased while there was an increase in incidence of sarcomas and lymphomas. Among young persons, the occurrence of oral carcinomas (mostly SCC) is rare but sarcomas were more common in younger patients. Gingiva was the most frequently involved in oral cancers with (46%), followed by tongue with (18%). CONCLUSION: : According to this study it revealed that some changes in trends of oral cancer have happened in Isfahan that calls for more study and evaluation of etiologies of these changes.

Incidence of cleft lip and palate in Iran. A meta-analysis.

OBJECTIVE: To investigate meta-analysis of published data on overall incidence of cleft lip, cleft palate, and cleft lip and palate of newborns in Iran. METHODS: This meta-analysis was carried out at the School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran between May 2009 and December 2009. Our data were consisted of all incidences of cleft lip and palate from 1978 to June 2009, and we selected 11 studies. Inverse-variance weighting was implemented to calculate the random effect summary estimates and to produce a forest plot. Cumulative meta-analysis on published data was calculated and grouped. Publication bias was checked using both Begg's and Egger's test. RESULTS: Pooled incidence from 11 studies was 1.0/1000 (95% confidence interval: 0.5-1.5). There was no evidence of publication bias among the 11 studies (p-values for Begg's test was 0.53 and for Egger's test was 0.23). CONCLUSION: The incidence of cleft lip and palate in Iran was lower compared to other countries.

Comparison of accuracy of uncorrected and corrected sagittal tomography in detection of mandibular condyle erosions: an exvivo study.

BACKGROUND: Radiographic examination of TMJ is indicated when there are clinical signs of pathological conditions, mainly bone changes that may influence the diagnosis and treatment planning. The purpose of this study was to evaluate and to compare the validity and diagnostic accuracy of uncorrected and corrected sagittal tomographic images in the detection of simulated mandibular condyle erosions. METHODS: Simulated lesions were created in 10 dry mandibles using a dental round bur. Using uncorrected and corrected sagittal tomography techniques, mandibular condyles were imaged by a Cranex Tome X-ray unit before and after creating the lesions. The uncorrected and corrected tomography images were examined by two independent observers for absence or presence of a lesion. The accuracy for detecting mandibular condyle lesions was expressed as sensitivity, specificity, and validity values. Differences between the two radiographic modalities were tested by Wilcoxon for paired data tests. Inter-observer agreement was determined by Cohen's Kappa. RESULTS: The sensitivity, specificity and validity were 45%, 85% and 30% in uncorrected sagittal tomographic images, respectively, and 70%, 92.5% and 60% in corrected sagittal tomographic images, respectively. There was a significant statistical difference between the accuracy of uncorrected and corrected sagittal tomography in detection of mandibular condyle erosions (P = 0.016). The inter-observer agreement was slight for uncorrected sagittal tomography and moderate for corrected sagittal tomography. CONCLUSION: The accuracy of corrected sagittal tomography is significantly higher than that of uncorrected sagittal tomography. Therefore, corrected sagittal tomography seems to be a better modality in detection of mandibular condyle erosions.

Low-level laser therapy and myofacial pain dysfunction syndrome: a randomized controlled clinical trial.

Myofacial pain dysfunction syndrome (MPDS) is the most common reason for pain and limited function of the masticatory system. The effects of low-level lasers (LLLs) for controlling the discomfort of patients are investigated frequently. However, the aim of this study was to evaluate the efficacy of a particular source producing 660 nm and 890 nm wavelengths that was recommended to reduce of the pain in the masticatory muscles. This was a double-blind and placebo-controlled trial. Sixteen MPDS patients were randomly divided into two groups. For the laser group, two diode laser probes (660 nm (nanometers), 6.2 J/cm(2), 6 min, continuous wave, and 890 nm, 1 J/cm(2) (joules per square centimetre), 10 min, 1,500 Hz (Hertz)) were used on the painful muscles. For the control group, the treatment was similar, but the patients were not irradiated. Treatment was given twice a week for 3 weeks. The amount of patient pain was recorded at four time periods (before and immediately after treatment, 1 week after, and on the day of complete pain relief). A visual analog scale (VAS) was selected as the method of pain measurement. Repeated-measures analysis of variance (ANOVA), the t-test and the paired t-test were used to analyze the data. In each group the reduction of pain before and after the treatment was meaningful, but, between the two groups, low-level laser therapy (LLLT) was more effective (P = 0.031) According to this study, this type of LLLT was the effective treatment for pain reduction in MPDS patients.

Cryosurgery (N2O) Application to Remove Lip Lesions of Lipoid Proteinosis Syndrome: A Case Report.

Lipoid proteinosis is a rare hereditary metabolic disorder transmitted as an autosomal recessive trait. It is characterized by the deposition of an amorphous hyaline-like material (glycoprotein) in the mucous membranes, skin and various internal organs. Cryosurgery (N(2)O) was applied to remove and reshape the lip lesions in a case of this rare syndrome. The patient was a 24-year-old female. Cryosurgery (-63ºC N(2)O for one minute) was performed to re-shape some areas of the upper lip. The lips were softer and had better esthetics after treatment. The use of cryosurgery offers advantages over surgery in reshaping of the lip lesions in this syndrome, since suturing is not feasible in rigid mucosa of these patients.