درمان ریشه

Calcium hydroxide (CH) is one of the most common intracanal medicaments. The residual calcium hydroxide along the root canal wall increases or decreases the sealing quality of the root canal filling. This study aimed to compare the leakage of different sealers in presence of calcium hydroxide.

In this in-vitro study, the 90 three-rooted and canal human mandibular molar teeth with mature apex selected with a curvature of less than 10 degrees were cleaned and shaped and divided into two groups (n=45). The first group was not medicated and the second group was medicated with calcium hydroxide. After 2 weeks, calcium hydroxide was removed from the root canal. Then the root canals were sealed using 3 different types of sealer (MTA Fillapex, AH26 and Endoseal MTA) with standard gutta percha and lateral condensation technique. The samples were immersed in India ink. After 4 weeks, the samples were demineralized and dehydrated. Apical leakage was measured by a microscope with a magnification of 0.1 mm. Data were analyzed using SPSS software and two-way ANOVA and Tukey HSD test

The lowest levels of leakage, both in the presence and absence of calcium hydroxide, were observed in the AH26, Endoseal MTA, and MTA Fillapex sealers, respectively. The leakage level in each sealer was lower in the absence of calcium hydroxide compared to its presence. Based on the two-way ANOVA test, the type of sealer (P<0.001), the use or non-use of calcium hydroxide (P<0.001), and the interaction between the type of sealer and the use or non-use of calcium hydroxide (P<0.001) had a significant impact on leakage. The mean leakage of the AH26 sealer was significantly lower than that of the Endoseal MTA and MTA Fillapex sealers (P<0.001). The mean leakage of the Endoseal MTA sealer was significantly lower than that of the MTA Fillapex sealer (P<0.001).

All sealers had apical leakage and filling with them with and without the calcium hydroxide did not completely prevent dye leakage. The leakage rate of AH26 was lower than the other two sealers and the leakage rate of MTA Endosael was lower than MTA Fillapex. In the absence of calcium hydroxide, the amount of leakage is less.

To achieve a successful root canal treatment, it is necessary to have a sealer with ideal characteristics that seal the permanent filling of the tooth canal. Over time, various sealers with different compositions have been introduced to increase the obturation quality of tooth root canals, and many studies are still ongoing to find the ideal sealer. This study aims to evaluate the obturation quality of Endoseal MTA sealer based on the void and spreader track in the root canal using intraoral digital radiography (PSP) and compare it with Adseal and MTA Fillapex.

This laboratory study was conducted on 36 central maxillary single-canal permanent human teeth with the same shape and in the pre-clinic of the dental school of Mazandaran University of Medical Sciences. Root canal preparation was done with the Denco rotary system up to size F3 according to the manufacturer's instructions. During preparation, sodium hypochlorite 5.25% was used for washing, and finally  EDTA 17% and sodium chlorite 5.25%  were used to remove the smear layer. The teeth were dried with a paper cone. The samples were randomly divided into 3 groups and were filled with gutta-percha and sealers; MTA Fillapex, Endoseal MTA, and Adseal by lateral compaction method using Master Cone 35 and cone 20. After the sealers were set completely for 24 hours, PSP imaging was done with a parallel technique, buccolingually and mesiodistally, from the root canal of the teeth, and the presence of void and gaps in the form of spreader track in the three apical, middle and coronal regions, was evaluated with 3 independent observers. The data were evaluated with chi-square or Fisher's exact test, and items less than 0.05 were considered significant.

In the current study, the obturation quality of MTA Fillapex, Endoseal MTA, and Adseal sealers was investigated on 36 teeth based on void and gap in the form of spreader track. These evaluations were done according to the direction and location of the sealers. In these evaluations, Adseal sealer had the lowest and MTA Fillapex had the most prevalence of spreader track prevalence, although these differences were not significant based on the chi-square test and there was no significant difference between the prevalence of Spreader track among the three sealers. The void was observed only in the Endoseal group in coronal (mean: 0.5) and apical (mean: 0.7) areas. The results of the Chi-square test showed that there was no significant relationship between the prevalence of void with coronal, middle, and apical sites in Endoseal (P<0.05).

No difference was observed between the three sealers in the voids and gaps in the root canal. Based on the results of this study, the obturation quality of the above three sealers isn't different from each other. Although the presence of more void in Endoseal MTA sealer was not significant, it can indicate that the handling of this material is difficult, on the other hand, according to the manufacturer's recommendation, this sealer is recommended for single cone method and is not suitable for use in lateral compression method.

Pain management has always been a challenge in dentistry and especially after endodontic treatments. Hence, this study aimed to evaluate the analgesic effect of an herbal medication containing ginger and pineapple extract, curcumin, and bromelain, called Anaheal Plus, after endodontic treatment, compared to Ibuprofen.

In this clinical trial study, 78 patients were randomly selected and divided into two groups. In group A, patients were asked to take 400mg Ibuprofen, whereas patients in group B,took Anaheal Plus before treatment. Pain intensity values were assessed and recorded using VAS scores. Pain was evaluated prior to endodontic treatment, as well as 6, 12- and 24-hours post-treatment. Mann-Whitney, Chi-square, Repeated measure ANOVA and Friedman tests were also applied to analyze the data.

The mean pain scores in groups A and B were 6.46±2.71 and 5.79±2.57 before treatment, 2.95±2.59 and 2.67±2.69 six hours after treatment, 1.49 ± 1.22 and 1.38± 0.79 12 hours after treatment, and 0.65± 0.31and 0.60± 0.28 24 hours after treatment, respectively. Statistical analysis showed no significant difference between Ibuprofen and Anaheal Plus groups in terms of the obtained pain scores during different time intervals.

The findings of this study revealed that both Anaheal Plus and Ibuprofen had similar effects in pain alleviation for patients receiving endodontic treatment. Therefore, Anaheal Plus can be considered as an alternative analgesic drug in endodontic treatment due to its fewer side effects in comparison with Ibuprofen

Success in endodontic treatment is directly related to proper diagnosis and neutralization of microorganisms using mechanical and chemical methods and full canal obturation. Given that technical errors can affect the success of treatment and cone beame CT can detect these errors perfectly, the aim of this study was to determine the frequency of technical errors in root canal treatment using CBCT

In this descriptive-analytical study, 1067 endodontically treated roots in CBCT stereotypes were investigated. Fine-grained diagnostic radiographies were investigated in coronal, sagittal and axial planes. Filling length errors (tip to tip obturation, underfilling, overfilling, voide), errors during preparation (perforations, transport, broken instruments, missed canal and vertical root fracture) were recorded. The data were analyzed by Chi-square and Fisher's exact test

Moreover, the highest technical errors occurred were transport (23.8%), overfilling (21.2%), underfilling (21.1%) and voide (17.8%) and the lowest technical error occurred was zipping (0.3%). The highest technical errors occurred in the anterior regions including single canal teeth (18.7%) and single canal premolar (11.4%) and the lowest technical errors were found in the buccal and lingual canal of double canal canines (4 %). The frequency of radiographic lesions (p = 0.005) and the expansion of PDL (p <0.001) were significantly different between different dental areas; however, the frequency of resorption was not significantly different between different dental areas (p = 0.11).

The highest observed error was in the anterior area of a canal and the lowest error rate determined by the CBCT was related to the two canal canine (buccal) and two canal canine (lingual). transport, short-term filling, and void were the most endodontic errors and the lowest ones were related to zipping cousing with broken file and post perforation  in the root canal treatment.

One of the concerns about orthodontic treatment is the external apical root resorption(EARR).Therefore, the aim of this study was to compare the rate of EARR in posterior permanent endodontically treated and vital teeth after orthodontic treatment.

This observational and retrospective study was performed on 112 roots in 28 patients in the age range of 20 to 30 referred to the orthodontic department of Isfahan Azad University who had endodontically traeted teeth on one side of the jaw and contralateral vital teeth on the opposite side. The studied roots were maxillary first and second molars roots (mesiobuccal and distobuccal roots), mandibular first and second molars roots (mesiolingual and mesiobuccal and distal). Two panoramic radiographs were taken before orthodontic treatment and at least one year after orthodontic treatment. In both radiographies, the ratio of crown length to root length was measured in the endodontically treated teeth and the contralateral vital tooth. The results were analyzed using Mann-Whitney test.

There was a significant difference in the external resorption of distal (p = 0.001) and mesial (p <0.001) roots between endodontically treated and contralateral vital teeth, but there was no significant difference between distobuccal and mesiobuccal roots of maxillary posterior permanent vital teeth (p=0.499), endodontically treated teeth (p = 0.249), mesial and distal roots of mandibular posterior permanent vital teeth (p = 0.398), endodontically treated teeth (p = 0.193).There was no significant difference in the external resorption of mesial roots of vital teeth (p. 0.075), mesial (p. 0.243) and distal (p = 0.324)roots of endodontically treated teeth between maxillary and mandibular teeth but a significant difference was observed in the distal roots in the vital teeth. (P = 0.014) and root resorption in the distal roots of the maxilla was more than the mandible.

External apical root resorption after orthodontic treatment in posterior endodontically treated teeth was lower than vital teeth.

Quality of root canal treatment is considered as an important prognostic factor for endodontic therapy success. The aim of this study is to evaluate radiographic errors during the root canal treatment by 5th and 6th year undergraduate students of Islamic Azad university of Isfahan (Khorasgan) from 2015 to 2018

In this study records of 860 cases of endodontic treatment of patients referred to the General Endodontics Department and the Comprehensive Treatment Department of Isfahan Azad University (Khorasgan) during 2015-2018 including 1903 root canals that had received root canal treatment were examined. Periapical radiography was used to evaluate errors during access cavity preparation, canal preparation, and canal filling by two endodontic specialists and it was recorded in pre-prepared forms. In the access cavity preparation: furcation perforation, low access cavity expansion, high access cavity expansion were evaluated. During the canal preparation phase, errors such as missing of canal, ledge, transport, perforation types and broken instruments were investigated. Length and density of root filing were the criteria evaluated at the canal filling stage. The analysis was performed at both descriptive and inferential levels. Statistical analysis was performed by Chi-Square test and exact Fisher's test.

Frequency of acceptable root canal treatment (without errors) was 37.5%. Lower first molars showed the highest error rate (40.7%). Furcation perforation was reported with 9.4% highest error of access cavity preparation. The highest error rate was reported transport (7.8%) in the preparation phase. Inadequate density (gap) of 36.9% and under filling of 31.1% had the highest error in filling stage.

According to the results of this study, it can be stated that general endodontics department needs careful planning to increase the quality of root canal treatments performed by students.

Bacterial disinfection is considered as the primary etiology of pulpal and periapical lesions and as the result, adequate elimination of such infections is one of the purposes of root canal treatment; But since this purpose is impossible to achieve, reducing the bacterial load seems to be as a rational goal. Diode lasers have made their way into endodontics for better disinfection and penetration into the root canal dentine. This study reports 3 cases of Diode laser assisted endodontic treatments in periapical lesions repair.

Case Report:

 3 patients referred to an endodontist for root canal treatment and 2 patients were treated with diode laser (wavelength of 940 nm and power output of 1W) and one patient was treated with diode laser (wavelength of 810 nm and power output of 1 W). The follow-up outcomes for all three patients showed the treatment success.

Diode laser can be used in root canal treatment of teeth with periapical lesions.

The students’ self-confidence level is a key factor affecting the success of endodontics learning. This study aimed to determine the confidence level of dental students who performing root canal treatment at Rafsanjan University of Medical Sciences in 2021.

In this cross-sectional study a questionnaire including demographic information, endodontic experience, attitude toward confidence in performing different stages of root canal treatment, and suggestions for improving the quality of endodontic education was distributed to dentistry students of 54 5th and 6th-year in the last month of the academic semester. Data were analyzed using t-test, Pearson, and ANOVA tests (α = 0.05).

According to the results, from 49 dental students, 24.5% reported the first cases of root canal treatment to be severe. The lowest confidence was reported for finding all root canals in teeth with multiple root canals, preparing access cavity and understanding and managing root canal treatment risks. According to the results of chi-square analysis test, the total confidence score between 5th and 6th year students was not significantly different (p value = 0.648). Also, the relationship between general self-confidence and students' self-confidence level was not seen (p value = 0.372). There was no significant relationship between the Confidence level and age, academic year, the difficulty level of the first endodontic treatment, and number of endodontic treatments (p value > 0.05).

Students had lower self-confidence finding all the canals in multi-canal teeth, how to properly manage the treatment risks, and preparing the access cavity. Endodontics training should also be improved by increasing clinical sessions and using recent advances in endodontics.

Successful endodontics training is the integration of students' skills and knowledge as the basis for mastery and competence in the work. Therefore, they can perform satisfactory non-surgical endodontic treatment on single-rooted and multi-rooted teeth. The present study aimed to determine the results and evaluate the success rate of endodontic treatment to improve the outcome of treatment conducted by general students of Mashhad Dental School in 2011-2012.

A total of 70 records of treated patients were reviewed by students, and they were recalled for follow-up. The success of endodontic treatment was firstly assessed based on clinical criteria and then based on radiographic criteria in one of three groups: success, failure, and unknown. Other factors including age, gender, tooth area, jaw, post-restoration, causes of inappropriate treatment, and student’s educational level that could affect success were also assessed.

In the present study, 74.3%, 20%, and 5.7% of treatments were successful, failed, and unknown, respectively. Twelve (17.1%) teeth were extracted. The highest success rate was observed in health restoration and it was clinically significant (P=0.076). Age, gender, type of teeth, and jaw also had no significant effect on treatment outcome (P> 0.05). Only a significant association was observed between students' courses and the success rate of treatment (P <0.05). Also, the highest success rate was seen in proper root canal treatment and health restoration (96.4%), but there was no statistically significant association (P=0.448).

The success rate of the 70 endodontic treatments performed by undergraduate students from Mashhad dental school was 74.3%. Proper restoration after root canal therapy is a factor affecting the treatment results.

Digital and film-based radiography are the most common methods of working length determination. The objective of this study was to compare the accuracy of working length determination of curved canals using digital and film-based radiography.

This experimental and interventional study, included forty teethwith curved canals conducted atthe Dentistry Faculty of Isfahan University of Medical Sciences, in 2018. After access cavity preparation, the direct observation method of the apical tip of the file in the root apex determined the actual working length. Teeth were mounted in acrylic blocks. Canal curvature was calculated based on Schneider’s method using software of indirect digital radiography. Images gathered by E-speed film and digital sensors. A pre-curved file was used to measure the working length offilm-based images. In digital radiography, a digital caliper was used to measure the working length with three and six clicks. Data were analyzed by repeated measure analysis, paired t-test, and Intraclass Correlation Coefficient. The Level of significance was set at 0.001.

All groups overestimated the actual length although there weren’t any significant differences (p value > 0.05). Paired t-test didn’t show any significant differences between digital and film-based groups (p value > 0.05).

Considering several advantages of digital radiography over the film-based method, it is the preferred method for working length determination of curved canals.

Enterococcus faecalis (E. faecalis) is one of the microbes of the normal flora of the oral cavity, which is one of the common factors in the failure of root canal treatment. This in vitro study aimed to evaluate the ability of barberry extract to prevent the formation of microbial biofilm by E. faecalis.

Initially, E. faecalis was cultured simultaneously with barberry bark and root extract, and biofilm formation was evaluated after 48 h. In the second stage of the active culture of the bacteria (48 h), all root and bark concentrations had similar growth inhibition with the control group. The same results were observed after two weeks. Fluorescence staining with SYPRO® Ruby (Invitrogen, USA, 2010) was used to confirm the formation of biofilm. Subsequently, all samples were examined by fluorescence microscope, and the results were reported using Relative Fluorescence Unit.

In the simultaneous cultivation of barberry and E. faecalis, root (30%), growth medium (50%), and bark (30%) had similar growth inhibition with the control group. After adding barberry bark and root extract (48 h), all concentrations of barberry bark and root showed similar growth inhibition with the control group. After two weeks of E. faecalis culture, the results were the same as those of the first group. However, wide and thick biofilms were formed in the samples without treatment and those treated with normal saline.

Due to the positive effects of barberry bark and root extract, it can be used to sterilize dental canals and can be considered a suitable alternative to hypochlorite.

Producing a new sealer using local technology helps to produce dental materials with ideal properties in the country and at a lower cost. The present study was performed to investigate the physical properties of a calcium silicate- and hydroxyapatite-based endodontic sealer in three different mass compositions.

In this laboratory study, a new sealer was made in Mashhad Dentistry School. Three different weight ratios in the experimental groups S1= Cs Si Sr, S2= Cs Si2 Sr and S3= Cs Si Sr2 were evaluated in terms of setting time, working time, film thickness, solubility, and flow. Experiments were performed according to ISO/FDIS6876:2012 standard. To determine the crystal structure of the sealer in three different formulas, the samples were examined by X-ray and Energy-dispersive X-ray Spectroscopy.

The highest amount of flow was related to S1 (17.08 mm) and the lowest amount was related to S2 (16.2 mm). The lowest solubility was related to the formula S1 (1.83%) and the highest was related to S2 (3.6%). Experiments also showed that the amount of film thickness in the formula S2 and S1 have the highest and lowest levels, respectively. Setting time in the samples was 330 minutes in S1, 428.33 minutes in S3 and 1030 minutes in S2. S1 had the longest working time, followed by S3 and S2, respectively.

Based on the results of this study, sealers S1 and S3 showed good results in accordance with the standards in setting time, working time, film thickness, solubility, and flow tests, but sealer S2 showed results close to the standard.

Due to the importance of the administration of antibiotics in eliminating pulp and periapical microorganisms, this study aimed to evaluate dentists' knowledge about antibiotic administration in root canal treatment in Gorgan, Iran.Materials &

In this cross-sectional descriptive/analytical study, 115 questionnaires with confirmed validity and reliability were distributed among dentists in Gorgan. The questionnaires included demographic data and antibiotic administration habits of dentists in different types of endodontic therapy. Finally, 103 completed questionnaires were analyzed statistically with SPSS 16.0, using chi-squared test (α = 0.05).

The awareness of dentists about antibiotic administration in patients with acute pulpitis, acute apical abscess, and chronic periodontitis was 81.6%, 56.3%, and 64.4%, respectively. None of the dentists believed in routine antibiotic prophylaxis in root canal therapy, and 80.4% prescribed 2 g of amoxicillin as their preferred antibiotic prophylaxis, if needed.

According to the results, despite the favorable level of dentists' awareness of antibiotic administration, there is still some tendency for indiscriminate use of antibiotics by dentists in Gorgan compared to the standard indications for antibiotic administration, indicating the need for increasing the awareness of dentists in continuous education programs.

Periapical inflammatory lesions are localized periapical bone reactions that result from pulp necrosis and inflammation or periodontal diseases. Inappropriate treatments are often considered as one of the main factors associated with apical periodontitis. This study was done to evaluate periapical radiolucencies in panoramic radiographs.

In this cross-sectional study, 332 panoramic radiographs of patients attending Sari School of Dentistry (2016-2019) were assessed. The Periapical Index was used to evaluate the presence of periapical lesions. Also, the quality of treated teeth was determined by optimal quality indices. Data analysis was done in SPSS V.016

Periapical lesions (PAI = III-V) were seen in 75.4% of the teeth investigated and in 90.2% of teeth with root canal therapy (RCT) and 68% of untreated teeth. Periapical radiolucencies were mostly found in RCT teeth with inadequate filling density and length. The prevelance of lesions were higher in males. The presence of lesions increased in jaws from the anterior to the posterior, and the frequency of lesions was higher in the maxilla than the mandible.

The frequency of periapical lesions in RCT teeth was very high. The findings showed that the quality of density and length of filling has a significant effect on prevelance of preapical lesions. Poor RCT leads to low success rate in the treatment of teeth.

Periapical diseases are the result of untreated pulpitis or inadequate treatment of root canals. This study aimed to investigate the prevalence of different periapical lesions according to demographic variables in patients attending the departments of oral pathology in Mazandaran province, Iran 2012 to 2017.

In this cross-sectional descriptive study, 233 biopsy samples were studied. The age and sex of the patients and the location and type of periapical lesions were investigated. Data analysis was done in SPSS V24 applying Chi-square test, Fisher’s exact test, ANOVA, and Tukey test.

Biopsies belonged to both males, n=118 (50.6%) and females, n=115 (49.4%). The mean age of the patients was 37.8 years (12 to 84 years old). In this study, 152 (65.2%) lesions were radicular cysts, 50 (21.5%) were dental granulomas, 7 (3%) were osteomyelitis, 22 (9.4%) were residual cysts, and 2 (0.9%) were lateral cysts. The most common sites of involvement were the posterior region of the mandible (48.8%) and the anterior region of the maxilla (24.2%). 

Periapical lesions in teeth are highly prevalent, so it is important to increase people awareness on oral hygiene and prevent these lesions.

Root therapy will be successful if it is done based on a correct diagnosis and appropriate treatment plan with the knowledge of morphology and tooth anatomy, debridement, disinfection, and obturation of the entire root canal system. This study aimed to investigate the number and morphology of canals in root canals mandibular anterior using cone beam computed tomography (CBCT).

A cross-sectional descriptive study was performed in a private office in Tehran, Iran 2018, and 902 anterior teeth were evaluated. Teeth were selected according to the following criteria: complete evolved roots, absence of periapical lesion, and no history of root healing. CBCT images were evaluated from three dimensions of sagittal (root number, canal type, and apical foramen deviation from radiographic apex), coronal (apical foramen deviation from radiographic apex), and axial (canal type and apical foramen diameter). Data analysis was done in SPSS V16.

The mean apical foramen diameter was 0.21 ± 0.55 and the mean apical foramen deviation from the radiographic apex was 0.66 ± 0.48 mm. Class 1 and 3 morphologies were the most frequent classes observed in anterior teeth and other classes accounted for about 5% of the samples.

In this study, there was no relationship between gender and the number of roots and in males the number of canals were higher than that in females.

Apical root Resorption is a common occurrence during fixed orthodontic treatment. This study used panoramic radiographs to compare the rate of root resorption in endodontically-treated and non-endodontically-treated roots.

In this descriptive-analytic study, panoramic radiographs of 20 patients aged 11-18 years with Class I Crowding and Class II Mild Skeletal malocclusions and with one or more endodontically-treated maxillary anterior teeth in one side and corresponding non-endodontically-treated teeth on the other side of the jaw were selected. They had presented to Dental School of Shahid Sadoughi University of Medical Sciences and private dental offices in Yazd. All panoramic radiographs of central and lateral maxillary incisors obtained before and after treatment were scanned and displayed on a large monitor with X2 magnification. In this way, the real magnitude of root degeneration was estimated by comparing the root heights in the pre- and post-treatment radiographs. The data were analyzed by SPSS 22 and T-test.

The findings showed that the greatest rate of root resorption was observed in the upper maxillary lateral incisors of endodontically-treated teeth by 1 mm and in maxillary lateral incisors of the non-endodontically-treated teeth by 1.5 mm. The mean root resorption was 0.325 mm in the endodontically-treated teeth and 1.025 mm in the non-endodontically treated teeth with a statistically significant difference (P>0.001).

The results demonstrated that root resorption was smaller after treatment in endodontically-treated teeth than non-endodontically-treated teeth.

Root canal therapy is one of the most important treatments for oral and dental health. To a large extent, the success of treatment is dependent on endodontic treatment errors, and since the treatment errors are affected by the type of dental education, the aim of this study was to compare the prevalence of errors during root canal treatment by students, entering the university in 2010-2012, who were trained with and without the use of a head phantom in the Faculty of Dentistry, Isfahan University of Medical Sciences. In this descriptive-analytical study (historical cohort), 400 records were collected from the students entering the university in 2010, who were trained without a head phantom, and 400 cases related to students entering the university in 2012, who were trained with a head phantom. The records were first coded by one of the members of the admission department and then examined by two researchers for the root canal errors during the stages of access cavity preparation, root canal preparation and obturation of the root canals. These errors were collected in a double-blind manner and analyzed with SPSS 20, using Chi-squared test. Statistical significance was set at p value < 0.05. In this study, root canal treatments rendered by dental students of Isfahan University of Medical Sciences were proper in 67.5% of the cases and the prevalence of root canal treatment error was 32.5% among students. The highest frequency of root canal errors among students was related to overfilling (43.9%) and the least error was related to furcal perforation (0.37%). The prevalence of root canal treatment errors among students entering the university in 2010 and 2012 were 41.6% and 24.4%, respectively. The present study showed that the prevalence of endodontic treatment errors by students trained with a head phantom was significantly less than that by those who were trained without a head phantom. Therefore, it can be concluded that the teaching of dental students using head phantoms can reduce root canal treatment errors by students.

Pain control in dental treatment, especially in root canal treatment, is an important issue. The aim of this study was to investigate the effect of dexamethasone infiltration along with the inferior alveolar nerve block with lidocaine with 1:80000 epinephrine on postoperative pain in posterior teeth with irreversible pulpitis. In this clinical trial, 60 patients with irreversible pulpitis and acute pain in lower molar teeth were selected and randomly divided into two groups. After standard block injection for each patient, buccal infiltration injections of dexamethasone or normal saline solution was performed. Preoperative pain was recorded using visual analogue scale (VAS) from 0 to 10 before treatment, and at 4-, 6-, 12- and 24-hour postoperative intervals. Data were analyzed with independent t-test and chi-squared, Mann-Whitney and Friedman tests (α = 0.05). There were no significant differences between the two groups in age, sex, tooth and pain severity before treatment. Pain in the control group 12 and 24 hours after treatment was significantly less severe than that at 4-hour interval; however, in the dexamethasone group this difference was not significant. By controlling confounding factors, preoperative pain significantly affected the pain after treatment at 4 and 6 hours. Gender affected pain at 12-hour postoperative interval. Buccal infiltration of dexamethasone significantly affected pain at 4- and 6-hour postoperative intervals. Preoperative pain significantly affected pain at 4- and 6-hour postoperative intervals in mandibular molars with irreversible pulpitis.

Periapical diseases are the end result of untreated pulpitis or failure of root canal therapy. The aim of this study was to evaluate and compare the prevalence of different periapical lesions in terms of demographic variables in patients referring to the Department of Oral Pathology of Isfahan Dental School in three different time periods from 1988 to 2015.
In this retrospective cross-sectional study, biopsy samples available in the archives of Oral Pathology Department of Isfahan Dental School from1988 to 2015 were studied. Periapical (PA) lesions were evaluated and compared in terms of age, sex, type, etiology and location. Data were analyzed with SPSS. After data collection, data were analyzed with chi-squared test, Fisher’s exact test, ANOVA and Tukey test (α = 0.05).
Of 10686 oral biopsies, 582 (5.44%) were PA lesions. Of 582 PA lesions, 71.1% were dental granulomas and 15.3% were radicular cysts and the other cases were other lesions with lower prevalence rates; 41.4% of the lesions belonged to males and 58.1% to females. The most common frequency was detected in the 21‒30-year age group. The most common site of involvement was the mandibular molars with 48.3%, maxillary incisors with 32.5% and maxillary molars with 21.4%, respectively. Distribution frequencies of PA lesions were 11%, 23.9% and 65.1% in the first, second and third periods, respectively.
The results showed that the prevalence of PA lesions has increased significantly in recent years. Increased incidence of periapical lesions secondary to root canal therapy (RCT) in the second and third periods in comparison with the first period is an indication of inadequate RCT treatment in patients.