Journal of Dental Medicine

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.

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.

Background and Aim: Several materials have been introduced for retrograde fillings, pulp capping and sealing root perforations, but their biological effect on vital tissues and cells is not clear. The purpose of this study was to evaluate the reaction of human periodontal ligament fibroblasts to four root canal filling materials: Pro Root MTA, Root MTA, Portland cement and amalgam.

Materials and Methods: In this experimental study, impacted or semi impacted third molar teeth were extracted in aseptic conditions and tissues around the roots were used to obtain fibroblast cell line. After proliferation, cells were cultured in chamber slides and extracts of materials were added to wells. Fibronectin, type I collagen and TGF-  expression were measured by immunocytochemistry method. Data were analyzed by SPSS 11.0 using one way ANOVA and Tukey test. P<0.05 was considered as the limit of significance.

Results: Collagen I expression was higher in Pro Root MTA group after 24 hours (p<0.05) and in Portland cement group and positive controls after 48  hours. Portland cement group showed the highest expression of collagen after 1 week. There was no significant difference in fibronectin expression after 24 hours. After 1 week the highest expression of fibronectin was seen in Portland cement, Root MTA and Pro Root MTA groups. TGF-  expression was higher in amalgam, Root MTA and Pro Root MTA specimens after 24 hours and was the highest in Pro Root MTA group after 48 hours.

Conclusion: Based on the results of this study, Portland cement and Root MTA are comparable with Pro Root MTA and better than amalgam regarding their effects on human periodontal ligament fibroblasts.

Background and Aim: Three Dimensional obturation of root canal is one of the main goals of root canal therapy to preserve health or reach the regeneration or healing of periapical tissues. Root end filling materials are used in numerous situations to reach the mentioned goals. One of the common root end- filling materials is mineral trioxide aggregate (MTA) which the foreign and Iranian ones are different in their prices. The aim of this study was to compare the rat connective tissue reaction to Iranian and foreign MTA.

Materials and Methods: This was an animal study in which 40 rats were divided into 5 groups of each 8. The polyethylene tubes filled with foreign (Pro Root MTA) and Iranian (Root MTA) white MTA and were implanted in subcutaneous connective tissue. Similarly, the empty tubes were inserted in subcutaneous connective tissue as control group. The samples were examined histologically after 7, 14, 30, 60 and 90 days and were scored as followings: 0, was characterized to samples without inflammatory cells without inflammatory reaction 1, for samples with less than 25 inflammatory cells mild inflammatory reaction. 2, for samples with 25 to 125 inflammatory cells moderate inflammatory reaction and 3, for ones with more than 125 inflammatory cells severe inflammatory reaction. The data were analyzed using Kruskal-Wallis test and p<0.05 was considered as the level of significance.

Results: In general, inflammatory reactions were reduced in all groups. Experimental groups had moderate to severe inflammation in the 7th day which had significant difference with the control group having mild to moderate inflammation (p=0.04). There was not any significant differences between experimental and control group in 14th, 30th, 60th and 90th days (p>0.05).

Conclusion: Based on the findings of this investigation, inflammatory subcutaneous connective tissue reaction to Iranian (Root MTA) and foreign (Pro Root MTA) MTA was the same.

Background and Aim: Several agents were used for pulpotomy in primary molars. Formocresol is the most common drug in this procedure. In some studies it has been shown that, this material has potential some side effects, so it is essential to find other alternatives. The aim of this study was to evaluate clinical and radiographic success rates of mineral trioxide aggregate and formocresol.

Materials and Methods: In this randomized clinical trial study, 70 carious primary teeth of 4 to 7-year-old children were pulpotomized, and remaining pulp was dressed with Root MTA and formocresol. The clinical and radiographic follow up evaluations were performed at 6, 12 months by a blind dentist. The data were analyzed by Fisher's exact test.

Results: At the end of 1-year follow-up period, in formocresol group sinus tract and tenderness to percussion were seen in 2 teeth, internal resorption was seen in 1 tooth, and furcation radiolucency was seen in 2 teeth. Clinical and radiographic signs of failure were not seen in any case of (Iranian) Root MTA group.

Conclusion: Based on the results of this study, Iranian MTA can be used for pulpotomy in primary molars.