Iranian Endodontic Journal

INTRODUCTION: Studies have shown the regulatory role of Leptin in bone formation, its expression in adipose tissue as well as increased levels in circulation following the adminstration of inflammatory stimuli such as lipopolysaccharides (LPS). However, there is little data evaluating the role of Leptin in inflammatory periapical lesions. The aim of this study was to evaluate the presence and concentration of Leptin in chronic periapical lesions. MATERIALS AND METHODS: Chronic periapical lesions with different sizes were collected during periapical surgery of the mandibular molars from twenty patients and cultured for 72 hours. The ELISA method determined the concentration of Leptin in supernatant fluids of explants cultures. Statistical analysis was performed using non-parametric tests (Mann-Whitney U, Chi-Square and Spearman’s Correlation Coefficient). RESULTS: Leptin was found in all samples with the average concentration of 405.55±102.98 (pg/mL). There was no significant correlation between the concentration of Leptin and BMI, and the diameters of lesions. CONCLUSION: Leptin can be considered an inflammatory mediator and is likely to have a role during the early phases of dental periapical lesions.

INTRODUCTION: Sealing ability is an important factor for a root-end filling material in endodontic surgeries. This in vitro study aimed to compare the sealing ability of mineral trioxide aggregate (MTA) and a new endodontic cement named calcium enriched mixture (CEM) cement as root-end filling materials. MATERIALS AND METHODS: The experiments were carried out in dry, saliva or blood contaminated root-end cavities of hundred single-rooted extracted human teeth. After decoronation, the root canals were cleaned, shaped, obturated, and stored in 100% humidity for 5 days. Removing the apical 2-3mm of each root, a 3mm deep root-end cavity was ultrasonically prepared. Samples were randomly divided into 2 test groups of 45 roots/experimental material, and one subgroup (n=15) for each environmental condition as follows; a) dried before placing the filling material, b) filled after contamination with saliva, and c) filled after contamination with blood. Ten roots were used as positive/negative controls. Samples were placed in an incubator at 37^°C for a day and immersed in methylene blue dye under reduced pressure environment for 48hours. Roots were sectioned longitudinally and examined under stereomicroscope by an independent observer. RESULTS: Using Kruskal-Wallis and Mann-Whitney U tests with Bonferroni correction, the results demonstrated significantly less leakage for the CEM cement in saliva contaminated condition when compared to MTA (P<0.001). CONCLUSION: It can be concluded that the sealing ability of CEM cement was superior to MTA in saliva contaminated condition.

INTRODUCTION: Pulpotomy of carious primary teeth with an exposed pulp is a common treatment option. Pulpotomy has been conducted with various medicaments over the years. The aim of this study was to evaluate clinical and radiographic success of primary vital pulpotomy with ProRoot and Root MTA. MATERIALS AND METHODS: In this randomized clinical trial, children aged between 3-7 years who met the inclusion criteria were enrolled. A total of 70 teeth were deemed suitable under the inclusion criteria and teeth were randomly divided into the 2 groups; ProRoot and Root MTA. Pulpotomy was performed and immediately followed by coronal amalgam restoration. The clinical and radiographic follow ups were conducted 6, 12, 18, 30 months post-operatively. The data were analyzed using Exact Fisher test. RESULTS: At the final follow up, 28 teeth in ProRoot MTA and 26 teeth in Root MTA were evaluated. In the Root MTA group, 1 tooth had exfoliated and one had an abscess and furcal radiolucency radiographically. In ProRoot MTA group, external resorption was observed in 1 tooth. Statistical analysis did not show significant difference in success rate between 2 groups after 30 months. CONCLUSION: The success rates of Root and ProRoot MTA are similar, indicating that pulpotomy can be carried out successfully in both primary molars.

INTRODUCTION: The purpose of this study was to evaluate the efficacy of three methods in removal of Resilon/new Epiphany self-etch (SE) soft resin endodontic obturation system. MATERIALS AND METHODS: Thirty extracted single rooted human teeth were prepared for endodontic treatment and obturated with Resilon/Epiphany SE. The roots were randomly divided into three groups; group 1 roots were retreated using Mtwo R/Mtwo files; group 2 were retreated using Mtwo R/Mtwo accompanied with chloroform; and group 3 were retreated using Mtwo R/Mtwo accompanied with Endosolv R. The cleanliness of canal walls was determined using scanning electron microscopy. Data were analyzed using ANOVA and LSD tests. RESULTS: Endosolv R combined with rotary files was more efficient in material removal compared to chloroform combined with rotary files and rotary files alone (P<0.05). Also, chloroform combined with rotary file was more efficient than rotary file alone in removing filling material from the root canals. Significant difference was found within group 1 between the coronal third compared to the middle and apical thirds (P<0.05). In group 2, there were more material remnants in the apical third (P<0.05). In group 3, there was no significant difference between the three segments of the root canals (P>0.05). CONCLUSION: All techniques left filling material remnants and debris on the root canal walls. Endosolv R combined with rotary files most effectively removed filling materials from the root canals, especially in the apical third.

INTRODUCTION: The aim of the present study was to compare hand stainless steel K-files and Nickel-Titanium Profile 0.04 taper 29 series rotary instruments for their efficiency, procedural errors and time consumed in preparation of root canal system. MATERIALS AND METHODS: A total of 46 maxillary and mandibular first premolars extracted for orthodontic purposes were collected (two contralateral teeth from each individual). The samples were divided into two groups of 34 canals each. Teeth in the first group were prepared with stainless steel hand K-files while the second groups were prepared with profile 0.04 taper series 29 rotary files. Preparation period was recorded for both groups. Impression material was introduced into the prepared canals so that the replica of prepared canals was achieved. These were assessed under stereomicroscope to assess the efficiency in preparing canals in respect to canal smoothness, ability of impression material to flow and quality of taper. Statistical analyses were performed using t-test, Chi-square and Fishers exact tests. RESULTS: Results showed significantly shorter preparation time for Profile than K-file. 8.8% of the canals prepared with K-files showed canal blockage, while all canals prepared with Profile remained patent. Alterations in working length working distance appeared in 23.5% of canals prepared with K-file and 11.7% in canals prepared with Profile. Failed instruments in K-files were significantly higher, mostly deformation (P<0.001). Profiles failed instruments were in the form of fracture and no deformation was detected. Both systems showed unsatisfactory walls smoothness and flow. CONCLUSION: Within the limitation of this study it was concluded that Profile 0.04 taper series 29 rotary systems prepare canals more rapidly, and have lower incidences of fracture and blockages, and only limited loss of working length. Canal preparation with K-file was time consuming and showed higher incidence of deformed instruments; overall, rotary instruments seem to offer greater advantages.

INTRODUCTION: This study compared the cleaning efficiency of Mtwo, Race and Medin Nickel-Titanium (NiTi) rotary instruments. MATERIALS AND METHODS: Sixty mandibular molar mesial roots were selected with angle curvatures between 25-35 degrees and divided into three groups; each containing 20 teeth. Canals were prepared with the rotary files and irrigated with 2.5% NaOCl solution after each instrument. Total of 5mL of normal saline was used as the final rinse; subsequently the canals were dried with paper points. The amount of debris and smear layer in three parts of the root canal walls was evaluated using SEM and the data were analyzed by using the Kruskal-Wallis test and the Mann-Whitney U test. RESULTS: The results for remnant debris in the coronal part of root canals were similar, whereas in the middle third, Mtwo instruments achieved significantly better results compared to Race and Medin instruments. In the apical third of the root canals more debris was created by Race instruments. CONCLUSION: Overall, Mtwo instruments had greater success in producing clean canals.

Persistent microorganisms in the root canal are known to cause endodontic treatments failure. Overextended gutta-percha can also act as a periradicular tissue irritant, leading to large periapical lesions. Retrieval of overextended gutta-percha with a nonsurgical approach can prove to be a challenge. This case describes the nonsurgical management of a large periapical lesion associated with overextended gutta-percha. Retrieval of gutta-percha was attempted but the overextended portion could not be removed. Aspiration of the purulent exudate was done through the root canal followed by use of a triple antibiotic paste. After 2 weeks the antibiotic paste was replaced with calcium hydroxide, to enhance the osseous regeneration. The periapical lesion showed a considerable amount of periapical healing after 15 months. The results of this case demonstrate that aspiration in conjunction with the triple antibiotic paste and calcium hydroxide may possibly be used in managing large periapical lesions associated with overextend gutta-percha.

The importance of the role played by bacteria in the pathogenesis of pulpal and apical disease has been established. One of the characteristics of apical periodontitis is apical bone resorption, which is due to apical immune response to bacterial infection. Recently, novel bacterial complex lipid called phosphorylated dihydroceramides has been discovered to be of inflammatory activators. The bacterial lipids stimulate prostaglandin E2, IL-6, and TNF-a secretion, inhibit osteoblast differentiation and function, and induce osteoclast formation. The biological activities are in Toll-like receptor 2 (TLR2)-dependent manner. These new findings imply that bacterial lipids could be important virulent factors that cause apical bone resorption. Future investigations may determine the significance of the bacterial lipids in the pathogenesis and treatment of endodontic diseases.