Journal of Dental Medicine

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The root trunk (RT) of molar teeth is important diagnostic parameter that has a key roll in diagnosis and treatment planning.The purpose of this study is presenting a normal index of RT in mandibular molar teeth in different buccal (B). distal (D), Lingual (Li) and mesial (M) entrances, and to compare them with each other.It is a case series study that 351 extracted molar teeth, after removal of soft tissue and debridement of calculus, evaluated with gauge (with accuracy 0.1 mm) According to our measurement:In maxilla: M-side: 3.88± 0.15 mm, B-side: 4.7± 1.7. D- side: 4.87± 0.13mm. So with P.value <0.05 M and D RT are longer than and M RT is shorter than D RT.In mandibule: B- side: 2.73± 0.11mm and L side: 4.03±- 0.13mm. So with P.value < 0.01 Li RT is longer than B RT.According to ochsenbine classification our studying teeth have medium to long RT. We prescribe for educating the crater therapy in periodontal surgery the emphasize must be focused on craters with medium and long RT.The shortness of RT in B-side of lower molars needed the most attention during osteoctomy in resective procedures. Because RT not depended to underlying factors such as age, social and economic situation,and for large amount of sample size in our study, the result could be extended in Tehran.

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One of the major goals of periradicular surgery is to create a good apical sea! at the apex. This is done by sectioning of 2 to 3mm from the apex, preparation of a class I cavity and filling with a biocompatible material.The purpose of this in vitro study was to determine whether ultrasonic units used for root end preparations could change the surface & structure of resected root ends, as competed to common methods of retropreparation. Eighty-five extracted single rooted teeth were divided into five similar groups. Then instrumented and filled with lateral condensation method. Then three millimeter of apex was resected, retropreparaiions in two groups were done with low speed handpiece and round V) ^ur and cavities in two other groups prepared with the highest power of dentspiay ultrasonic unit with TFI-10 tip and in one other group prepared with the highest power of neo sonic ultrasonic unit with diamond coated CT-1 retro tip.Following root resection and retropreparation the surface of resected root ends were examined for the presence of any cracks or structural changes on the surface of resected root ends with stereo microscope 50x.The results of this study showed thai high power settings of ultrasonic units can increase the potential of crack formation on resected root surfaces. In conclusion it is better to use low power setting of ultrasonic for retropreparation.

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Periodontitis affected root surfaces are hypermineralized and contaminated with cytotoxic and other biologically active substances.The instrumented surface will inervitably be coverd by a smear layer following root planing with or without flap.Smear layer is resistant to saline rinsing, but may be removed with agents such as acids (e.g.citric acid), tetracyclines, EDTA, and laser.Low pH aqueous solutions such as citric acid have been used in surgical periodontal therapy mainly for two reasons, It dissolves smear layer after a relatively short exposure time and it has been claimed to selectively remove root surface associated mineral exposing collagen to varying degrees. A root surface coated with collagen appears to be a preferred surface for fibroblast attachment, a cellular event fundamental to successful periodontal wound healing.Several studies indicate the potential of tetracycline (TTE-HCL) in periodontal regeneration. Its acidic pH suggest that it can be used as a demineralization agent and removing the smear layer and exposing collagen matrix of the dentin.Chalating agent (EDTA) working at neutral pH appears preferable with respect to preserving the integrity of exposed collagen fibers, early colonization, and wound healing. In addition, etching at neutral pH has been reported preserve adjacent tissue- vitality, while etching at low pH necrotizes the fiap and adjacent periodontium.Clinical and subclinical studies have demonstrated laser waves can remove calculus and bacterial plaque and pocket epithelium and strile the root surface and can expose the dentin collagen and dentinal tublules, and leads to pronounce reducing of probing depth around teeth diseased with periodontitis.

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Endodontic postoperative pain is still one of the major problems for dentists. According to the researches periapical inflammation after RCT is one of the most important factors causing endodontic postoperative pain. Histamine is one of the effective chemical mediators, which produces such inflammation. So, for controlling pains after RCT, the factors reducing inflammation should be found. The aim of this study was to investigate pain control after RCT by drug prophylaxis with antihistamine (asetemizole). 60 patients were divided in 2 groups (30 patients in each group). Group 1 had a capsule of  asetemizole (20mg) and the second group had a placebo capsule one hour before RCT. The patients completed the questionnaire after RCT and gave it back on the next session. The evaluated times were 1, 3, 6, 9, 12, 18, 24 and 72 h after RCT. This study indicated that asetemizole was able to reduce the moderate pericemental pain just at the 9 and 12 hours after RCT, and it was not able to reduce the spontaneous pain after RCT significantly on the evaluated times

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Statement of Problem: The main objective of endodontic therapy is chemomechanical cleansing of entire pulp cavity and its complete obturation with an inert material. During this procedure, the failure of detection and inadequate cleaning of a canal will result in failed endodontic therapy. Therefore, the dentist must have enough knowledge of root canal morphology to treat a tooth successfully.
Aim: The aim of this study was to determine the number and type of root canals of mandibular incisor teeth.
Materials and Methods: In order to do this in-vitro, descriptive study, 68 non-carious mandibular incisor teethj collected from different clinics in Yazd, were immersed in indian ink, decalcified and cleared.

Results: It was found that 55.9% of the teeth had two separate canals that in 5.5% of them, the canals merged before' apical foramen. In 4.4% of these samples, two separate canals existed along the whole root.
Conclusion: Considering high percentage of two canals in lower mandibular incisors, during access preparation, more attempts in detection of the second canal, is emphasized.

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Statement of Problem: The goal of a successful endodontic surgery is to establish an adequate seal in apical region. Therefore during surgery, root-end resection is essential for an appropriate situation and proper access.
Purpose: The aim of this study was to determine the most appropriate root-end resection angle to establish adequate apical seal in periapical surgery
Materials and Methods: Forty-five intact extracted human maxillary central incisors were randomly divided into three 15-tooth groups. The root canals were instrumented and then obturated using lateral condensation technique. AM roots were resected at 3mm from apical portion. Angles of root resection for each group were 0, 30 and 45 degrees. Then all teeth surfaces, except the cut ones, were covered with nail polish and immersed in methylen blue for 7 days. After 7 days, nail polish was removed from the surfaces and samples were split in buccolingual direction. Then, dye penetration (mm) was measured using a stereozoom microscope (Loupe) [X4 magnification] and eye lens. In order to analyze the data, unilateral variance analysis was used.
Results: The values of dye penetration were: 7.23±3.34 (0°), 8.46±3.01(30°) and 9.74±4.11 (45°). There
was no significant difference between three groups (P>0.05).

Conclusion: It is suggested that the angle of root-end resection put a limited effect on apical seal if retrograde cavity depth is increased.

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The use of root canal models in endodontics education is of high importance. So, in this article a new method is presented that the students can produce these models with simple and low cost instruments.These plastic models are made of polyester which is low cost, available and has the approximate cutting properties of dentin. The best molds were disposable syringes due to their low cost, availability and producing smooth surfaces on polyester models. A spreader with desired curve and tapering is used for producing canals. Rockwell A hardness coefficient of polyester is "33", which is near dentin "31" and foreign made models "35.5". Since these polyester models can tolerate up to 280°C and have acceptable resistance to chloroform, all root canal therapy techniques such as vertical condensation and retreatments are practicable. Their transparency encourage the students to work on them. As a result, the use of these models is recommended for endodontics training.

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Statement of Problem: Panoramic radiography seems necessary at examination, diagnosis and treatment plan phases of removable prostheses treatment since most of the patients who request removable prostheses treatment have retained root fragments, impacted teeth, cycts and tumors that might not otherwise be detected.
Purpose: The aim of the present study was to investigate the incidence rate of retained roots, impacted teeth and suspected pathologic conditions in panoramic radiographics of patients referred to removable prosthodontics departments of four dental schools and five public centers.
Materials and Methods: In this case series study, 1232 panoramic radiographs were analyzed to detect retained root fragments, impacted teeth and pathologic conditions.

Results: From among 850 panoramic radiographs of patients seeking complete denture, the incidence rates of impacted teeth, retained roots and pathologic lesions were 1.3%, 9.5% and 4.0% respectively.Also from 382 panoramic radiographs of removable partial denture patients the corresponding measures were 2.9%, 11% amd 0.1%.
Conclusion: Due to the significant and evident problems in residual ridge, as well as pathologic conditions of the remaining teeth structures and their supporting tissues as partial prosthesis base, the necessity for panoramic radiographics in edentolous and semi- edentulous patients is reemphasized.

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Statement of Problem: One of the dental lesions which is mainly diagnosed by periapical radiography is apical root resorption Diagnosis of the presence and extension of this lesion can put some effects on its treatment plan and prognosis.

Purpose: The aim of the present study was to evaluate the efficacy of periapical radiography on apical root resorption diagnosis. Materials and Methods: In this experimental study, sixty extracted teeth were examined radiographic and histological regarding the presence and extension of apical root resorption. It should be noted that periapical radiographs were taken before extraction of all mentioned teeth. The results were analyzed by Fisher’s exact test.

Results: The results of this study showed significant differences between radiological and histological examinations (P=0.0003). Significant correlation between these two observations was seen only in 53.33% of cases comprising 23% of teeth with root resouption. Non-correlation was found in 46% of samples. Moreover, there was no significant difference in the prevalence of apical root resorption between maxillary and mandibular teeth (P=0.233). Sensitivity of periapical radiographs in apical root resorption diagnosis was determined 57.3%. Conclusion: According to the findings of the present study, it seems that periapical radiography technique does not possess desirable efficacy in diagnosis of apical root resorption and its limitation should be considered by clinicians.

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Statement of Problem: There is a controversy about the relationship between pulpal and periodontal diseases. The interrelationship between pulp and periodontium could have an important effect on the treatment plan of the tooth.

Purpose: The aim of the present research is to evaluate root canal therapy effects on periodontal healing of teeth with chronic advanced periodontitis.

Materials and Methods: In this randomized controlled clinical trial 32 single rooted teeth which had necrotic pulp or irreversible pulpitis in 7 patients with chronic advanced periodontitis were selected based on specific criteria. Using a split mouth design, teeth were randomly put in two groups of test and control. In the test group root canal therapy ,scaling & root planing were done.In the control group, only scaling & root planing were performed. Clinical parameters including Pocket Depth (PD), Clinical Attachment Level (CAL), mobility, pattern of bone destruction and plaque index (PI) were evaluated in two groups at base line, 1 and 3 months after treatment. Appropriate tests such as paired Wilcoxon and Mann-Whitney were performed.

Results: Statistically significant reductions were found in the test group when comparing baseline and one-month post treatment values for Clinical Attachment level (CAL) but not after 3-months. In the control group the CAL reductions were not statistically significant between baseline and one month post-treatment, but a increase were observed between one month and three months after treatment. There was a statstically significant difference between the test and the control groups. Other parameters didn’t show any significant differences in each group and between two groups.

Conclusion: Since clinical attachment level was the most important parameter we found it can high lighted the role of pathogene with pulpal origin in progression of periodeontal disease and it is concluded that beside periodontal treatment in some advanced periodontal cases pulp therapy maybe an effective procedure for eleminating destructive pathogens of pulp and causing periodontal healing.

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The purpose of this article was reviewing the literature related to the mutual effects of endodontics and orthodontics on each other providing documented information that can be used by dentists in clinical practice. The effect of orthodontic treatment on the dental pulp and its role in root resorption, the influence of previous trauma to the tooth and endodontic treatment in orthodontic tooth movements and root resorption, recommendations regarding endodontic treatment during orthodontic tooth movement and the role of the orthodontic forces in provision and outcome of endodontic treatment are being discussed. The effect of the orthodontic tooth movement on the pulp is focused primarily on the neurovascular system which can cause degenerative and/or inflammatory responses in the dental pulp. Although, most of these changes are considered reversible, it seems that teeth with complete apical foramen and teeth subjected to previous insults, such as trauma, caries, restorations and periodontal diseases are more susceptible to pulpal irreversible changes. Teeth with root canal treatment that are well cleaned shaped, and three- dimensionally obturated, exhibit less propensity to apical root resorption during orthodontic tooth movement. This outcome depends on the absence of microleakage for bacterial ingress. A traumatized tooth can be moved orthodontically with minimal risk of resorption, provided that the pulp has not been severely injured (infection or necrosis). If there is evidence of pulpal demise, appropriate endodontic treatment is necessary prior to orthodontic treatment .If a previously traumatized tooth exhibits resorption, there is a greater chance that orthodontic tooth movement will enhance the resorptive process. If a tooth has been severely traumatized (intrusion, avulsion) there would be a greater incidence of resorption with tooth movement. It is recommended that teeth requiring root canal treatment during orthodontic movement be initially cleaned and shaped followed by the interim placement of calcium hydroxide. Final canal obturation with gutta-percha should be accomplished upon the completion of orthodontic treatment. Endodontically treated teeth can be moved orthodontically similar to teeth with vital pulps. In case of endodontic procedures like apexification, there may be no need to delay the orthodontic treatment.

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Background and Aim: Proper shaping and cleaning of the root canal system is one of the most important aspects of endodontic treatment. To estimate the canal length before instrumentation in endodontic treatment, traditionally, conventional radiographic techniques and recently Direct Digital Radiography (DDR) are applied. The application of computer technology to radiography has allowed less exposure time, image acquisition, manipulation, storage, retrieval, and transmission to remote sites in a digital format, elimination of wet processing and considerable reduction in the time lapse between image acquisition and display. The purpose of this study was to compare the accuracy of DDR versus conventional radiography in estimating endodontic file lengths of curved canals in first mandibular molars.

Materials and Methods: In this test evaluation study, fourty extracted human first mandibular molars with root curvature were selected.Samples were divided into two groups: With root curvature less than 25 and more than 25. Samples were mounted in plaster blocks and canal lengths were estimated by using DDR and conventional radiographs. Regression analysis and correlation coefficient were used to calculate statistical differences between the groups with P<0.05 as the limit of significance.

Results: Conventional radiography was more precise in canals with less than 25 degrees curvature (P=0.160). While, DDR was more precise for canals with curvature more than 25 degrees (P=0.605). However, these differences were not statistically significant.

Conclusion: The image quality of DDR system has improved to the point that it can now be used for estimating canal lengths, even for curved canals, with accuracy comparable to that of conventional radiography.

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Background and Aim: Today several materials have been used for root- end filling in endodontic surgery. Optimal properties of Pro Root MTA in in-vitro and in-vivo studies has been proven. On the other hand, based on some studies, Root MTA (Iranian Pro Root MTA) and Portland cement are similar to Pro Root MTA in physical and biologic properties. The aim of this study was to evaluate bacterial leakage (amount and mean leakage time) of four root- end filling materials.

Materials and Methods: In this experimental in-vitro study, seventy six extracted single- rooted human teeth were randomly divided into six groups for root-end filling with gray Pro Root MTA, white Pro Root MTA, Root MTA (Iranian Pro Root MTA), Portland Cement (type I) and positive and negative control groups. Root canals were instrumented using the step- back technique. Root- end filling materials were placed in 3mm ultra sonic retro preparations. Samples and microleakage model system were sterilized in autoclave. The apical 3-4 mm of the roots were immersed in phenol red with 3% lactose broth culture medium. The coronal access of each specimen was inoculated every 24h with a suspension of Streptococcus sanguis (ATCC 10556). Culture media were observed every 24h for colour change indicating bacterial contamination for 60 days. Statistical analysis was performed using log- rank test with P<0.05 as the limit of significance.

Results: At the end of study 50%, 56.25%, 56.25% and 50% of specimens filled with Gray Pro Root MTA, White Pro Root MTA. Root MTA and Portland Cement (type I) had evidence of leakage respectively. The mean leakage time was 37.19±6.29, 36.44±5.81, 37.69±5.97 and 34.81±6.67 days respectively. Statistical analysis of data showed no significant difference among the leakage (amount and mean leakage time) of the four tested root- end filling materials (P=0.9958).

Conclusion: Based on the results of this study, there were no significant differences in leakage among the four tested groups at 60 days. The results suggest that Root MTA and Portland Cement can be used as less expensive root filling materials.

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Background and Aim: External apical root resorption is a common iatrogenic consequence of orthodontic treatment. Much controversy exists in the literature about changes in root lengths at post treatment periods. Although many practitioners believe that resorption becomes stable after active treatment, quantitative data are scarce. The purpose of this study was to determine quantitative changes in root lengths of maxillary incisors during fixed orthodontic post treatment period, and to assess if it is influenced by gender and factors related to active treatment.

Materials and Methods: This was a case cross over study, performed on 80 patients (52 females and 28 males) aged between 13 and 22 years. At debonding stage and beginning of retention phase of fixed orthodontic treatment, Hawley type retainer was fabricated for maxillary arch. Periapical radiographs of maxillary incisors using standard parallel technique were obtained immediately after debonding, and 3 and 7 months later. Crown and root lengths of maxillary incisors were measured using computer program. Changes in root lengths were calculated considering correction factors. Also associations between some factors and the change in root lengths during post treatment periods were assessed. These included gender, type of treatment plan (non extraction/extraction), technique (standard edgewise/straight-wire edgewise) and duration of active treatment (less than 2 years/2 years and more). T-test and 4-way ANOVA were used for statistical analysis with P0.05 as the limit of significance.

Results: No significant relation was found between apical root resorption of maxillary central incisors and time elapsed after treatment. Significant relation was observed between apical root resorption of maxillary lateral incisors and the length of post treatment period. No significant relation was found between root length changes of maxillary incisors during post treatment period and gender, type of treatment plan, technique, and the length of active treatment period (P 0.05).

Conclusion: Considering the general process of root length reduction in maxillary lateral incisors during post treatment period, establishment of preventive measures is emphasized.

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Background and Aim: Determining correct working length in root canal therapy is of great importance in successful treatment. The purpose of this study was to compare the accuracy of two electronic apex locators of fourth generation, Raypex4 and Apit7, in determining working length in vivo.

Materials and Methods: In this test evaluation study performed at Dental School of Tehran University, a total of 32 single canal vital teeth planned for extraction because of orthodontic and prosthetic reasons were selected. Working length determination by each of the two electronic apex locators was performed by two different dentists. These measurements were compared with direct visual measurement after tooth extraction. The dentists working with devices and the endodontist who determined the working length of the extracted teeth as well as the statistician, all were blind regarding the results. The data were compared using binominal distribution test with P<0.05 as the limit of significance.

Results: The accuracy of actual length determination of Raypex4 was 68.8% in the limit of ± 0.5 and 83.3% in the limit of ±1. From the actual length measurements, 75.1% were within the tolerance of +0.5 to-1. The accuracy of the working length determination by Raypex4 was 68.8% within the tolerance of ± 0.5 and 84.3% within the tolerance of ± 1. Taking the tolerance of + 0.5 to -1 mm into account, the accuracy of the instrument was about 78.8%. The accuracy of actual length determination of Apit7 was 65.7% in the limit of ±0.5 and 78.3% in the limit of ±1. Compared to the visual length determination, 78.8% of the actual length measurements were within the tolerance of +0.5 to-1. The accuracy of the working length determination was 62.6% within the tolerance of ±0.5 and 81.3% within the tolerance of ±1. Taking the tolerance of + 0.5 to -1 mm into account, the accuracy of the instrument was about 75.1%.

Conclusion: Raypex4 and Apit7 had similar accuracy in determining the actual length. However, they still can not replace the routine methods of actual length determination.

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Background and Aim: Achieving appropriate seal in canal obturation is the main goal of endodontic therapy. However, in some cases, it can not be obtained by non-surgical procedures alone. Retrograde surgery is one of the most common procedures in endodontics. Apical seal improvement can be obtained by root end filling and decreasing the root end resection angle (bevel angle). The aim of this study was to investigate the role of bevel angle on apical microleakage following the use of amalgam and MTA as root end filling materials.

Materials and Methods: In this experimental study, 128 extracted human teeth were instrumented and obturated by lateral condensation technique. The teeth were divided into two groups and the apical root resection was performed by high speed fissure bur (one group perpendicular to the long axis of the teeth and the other 45 to the long axis. The 3 mm root end cavity was prepared by ultrasonic device. Each group was divided into two subgroups: One filled with amalgam and the other with MTA. Teeth were incubated for 72 h, covered by two layers of nail polish (except for apical 3mm) and submerged in methylene blue for 48 h. Teeth were washed under tap water and mesiodistally dissected by low speed disc. Dye penetration was evaluated by stereomicroscope. Data were analysed by two way ANOVA and Tukey tests with p<0.05 as the limit of significance.

Results: The results showed that retrofill material type had a significant effect on microleakage and MTA was superior to amalgam in this respect. Bevel angle failed to show any significant effect on apical microleakage.

Conclusion: Based on the results of this study, it seems that the use of MTA instead of amalgam in clinical practice can improve the success rate of endodontic surgery whereas the bevel angle can be determined based on the status of each individual case However, increasing the bevel angle seems to increase microleakage due to exposure of more dentinal tubules.

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Taurodontism is a rare dental anomaly in which the involved tooth has enlarged and elongated body and pulp chamber with apical displacement of the pulpal floor. Endodontic treatment of these teeth is challenging because it requires identifying the number of root canals. A case of bilateral involvement of maxillary first molar teeth is presented. Endodontic treatment of the right maxillary first molar with taurodontism was indicated due to irreversible pulpitis. In this article, we described the procedure of root canal therapy for this case.

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Background and Aim: The structural rehabilitation of a pulpless tooth is critically important to ensure a successful restorative outcome following endodontic treatment. A post and core is often indicated for the retention and reinforcement of the final restoration. But, the clinical situation is significantly challenging if the root exhibits immature development or there is a thin root wall that can compromise the prognosis for a long- term successful treatment. The purpose of this in vitro study was to evaluate different methods of intraradicular reinforcement in structurally compromised roots.

Materials and Methods: In this experimental study, seventy two extracted intact maxillary central incisors with similar size, shape and root anatomy were selected. After root canal therapy in 60 teeth, an acrylic laboratory bur was used to thin the cervical area and simulate the thin dentinal walls of immature teeth. The preparation was performed through the palatal access and extended 5mm apical to CEJ. The remaining 12 teeth remained unprepared to serve as positive control group. Cases were randomly divided into six groups of 12 teeth each and restored as follows. In the 12 cervically unprepared teeth (positive controls) the composite resin with dentin bonding agent (DBA) was placed in access cavity and cured for 120 seconds. This technique was also applied to other groups when the access was restored with composite. In the second group, the access cavity was restored with composite only to the level of CEJ. In the third group the cervically prepared teeth were reinforced with cement resin (Enforce) and a prefabricated post was placed in 5mm apical to the CEJ. In the fourth group, the cervically prepared teeth were reinforced with composite resin and DBA by a clear plastic post. In the fifth group the cervically prepared teeth were reinforced with composite resin and dba and a cast post. In the sixth group the cervically prepared teeth were restored with composite resin and dba with a prefabricated post. All of the specimens were mounted by rubberized technique and tested in the Instron universal testing machine. The fracture loads in samples were analyzed with ANOVA and Duncan tests with p<0.05 as the limit of significance.

Results: Significant differences in fracture resistance were observed between the first and second groups compared with others. The highest fracture resistance values were recorded for first group while the lowest were registered for the second group. Fracture resistance of the third, fourth and fifth groups had no significant statistical differences with others and fracture resistance of sixth group was the highest with significant difference (P<0.05).

Conclusion: From this study, it may be concluded that the use of a dba and a composite resin in thin-walled roots reinforces the immature teeth and facilitates the use of post.

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Background and Aim: Mineral Trioxide Aggregate (MTA) is a material used in many endodontic problems. Recently a number of studies, have reported that Portland Cement (PC) and MTA have similar physical, chemical and biologic properties. In addition, a material known as Root MTA which is produced in Iran has been claimed to have similar properties to Pro Root MTA. If these claims are true, possible use of PC and Root MTA in clinic instead of Pro Root MTA will be quite cost effective. The aim of this study was to investigate the toxicity of Pro Root MTA, Root MTA and Portland Cement on L929 mouse fibroblasts.

Materials and Methods: In this experimental study 0, 4, 24 hours and 7 days' extracts of materials were transferred to cell culture plates containing L929 fibroblasts. After 24 hours incubation, cells were stained by Neutral Red (NR), and optical density (OD) of each cell was read with ELISA reader. Data were analyzed using Tukey HSD and one way analysis of variance. P<0.05 was considered as the level of significance.

Results: In all surveyed groups and negative control group, at all time points separated cells from the base of the well were round. Refraction which is a characteristic of cellular death was not observed, whereas the separated cells from the base of well in positive control group showed refractional characteristic.

Conclusion: Based on the findings of this study Pro Root MTA, PC and Root MTA have the same biocompatibility. PC seems to have the potential to be used in the same clinical situation as MTA. However in order to replace MTA with these less expensive materials more in vitro and in vivo studies are suggested.

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Background and Aim: Root filling materials are usually in close contact with living tissues. So their biological properties like mutagenicity and cytotoxicity are important. These properties help us determine the potential damage to periapical tissues, or potential DNA mutations, and malignant transformation of the cells. The aim of this study was to evaluate the mutagenicity and cytotoxicity of four root canal sealers: AH Plus (Dentsply, DeTrey), Ketac-Endo Aplicap (3M ESPE), Sankin Apatite III (Sankin K.K), and Tubli-Seal EWT (Kerr).

Materials and Methods: In this experimental in vitro study fresh and set specimens from AH Plus, Ketac-Endo Aplicap, Sankin Apatite III, and Tubli-Seal EWT were immersed in culture medium for 1, 2 and 7 days. Cytotoxicity was assessed using tetrazolium bromide reduction assay (MTT) after 1, 2 and 7 days exposure of diluted extracts to L929 cells. Extracts of sealers in phosphate buffer saline (PBS) were used to examine the mutagenic effects by sos-umu test according to standard procedures. Data were analyzed using one way ANOVA, Kruskall Wallis, Mann Whitney and Post hoc tests with P<0.05 as the level of significance.

Results: Extracts of all freshly mixed sealers were cytotoxic. Ketac-Endo Aplicap and Sankin Apatite III showed the lowest toxicity respectively and Tubli-Seal EWT the highest. In contrast to other sealers, the cytotoxicity of Tubli-Seal showed no decrease with time. -galactosidase did not increase significantly thus none of the sealers showed mutagenic effects.

Conclusion: Based on the results of this study, Tubli-Seal EWT showed the highest cytotoxicity with time. Other sealers showed decreasing cytotoxicity with time. No mutagenicity effects was observed in none of  tested materials.