Original Article

Apical sealing ability of MTA in liquid to powder ratios and packing methods

Ehsan Oraie, Amir Reza Ghassemi, Gholamhosein Eliasifar, Masoumeh Sadeghi, Arash Shahravan

Iranian Endodontic Journal, Vol. 7 No. 1 (2012), 30 December 2011 , Page 5-9

Introduction: In apical surgery, after apicoectomy and retro-preparation of canal, a retrofil material is applied to seal the apical region of the root canal. Mineral trioxide aggregate (MTA) is the gold standard material for this purpose. Changing water/powder ratios of MTA affects its properties. The purpose of this in vitro study was to determine the effect of liquid/powder ratio of retrofil MTA on apical dye leakage, and also compare two packing techniques for MTA.


The effect of one-step or two-step MTA plug and tooth apical width on coronal leakage in open apex teeth

Zohreh Khalilak, Tabasom Vali, Farzad Danesh, Mehdi Vatanpour

Iranian Endodontic Journal, Vol. 7 No. 1 (2012), 30 December 2011 , Page 10-14

Introduction: Mineral trioxide aggregate (MTA) has been suggested as an effective material for apical barrier, forming an effective seal against bacterial leakage in teeth with open apices. MTA needs moisture for setting; which can come from the apical region or a moist cotton pellet. This study was intended to compare bacterial leakage in one- and two-step MTA apical barrier technique in open apices with different diameters.

Materials and Methods: The root canals of 52 extracted human maxillary incisors were prepared and open apices in two different diameters of 1 and 1.4 mm were created. The samples put in experimental groups randomly. A 4-mm thickness of MTA was placed as apical barrier for both one- and two-step methods. In one-step groups (1.4 mm diameter; n=12 and 1 mm diameter; n=12), the samples were obturated immediately after placing MTA plug. For two-step groups (1.4 mm diameter; n=12 and 1 mm diameter; n=12), a moist cotton pellet was placed over the MTA plug for 3 days before root canal obturation. Four samples served as positive/negative control groups. After one week, microleakage was evaluated using bacterial penetration technique and results were statistically analyzed utilizing SPSS software and Chi-square test.

Results: In one-step technique 13 and in two-step technique 12 samples showed bacterial leakage. There was no statistically significant differences between two techniques (Chi square, P=1). The difference between the results related to 1 and 1.4 mm apical foramens was also not significant (P=1). Also 12 and 13 samples showed bacterial contamination in teeth with 1 mm and 1.4 mm apical foramens, respectively (P=1).

Conclusion: It seems that leakage of MTA apical plug using one- and two-step technique is comparable; however, in vivo investigations are highly recommended for more accurate results.

Effect of calcium hydroxide and chlorhexidine medicaments on the apical seal

Mahmoud-Reza Hamidi, Elham Mahmoudi, Ali-Akbar Moghadamnia, samir zahedpasha

Iranian Endodontic Journal, Vol. 7 No. 1 (2012), 30 December 2011 , Page 15-19

Introduction: Leakage of the root canal system is an importent consideration when placing an intracanal medicament. The aim of this in vitro study was to compare the effect of calcium hydroxide and 1% chlorhexidine gel as intracanal medicaments on tooth apical seal.

Materials and Methods: Seventy extracted, single-rooted maxillary anterior teeth were divided into the three experimental groups (n=20). All root canals were instrumented with step-back technique and divided into three groups. Group 1 had root canal dressing with calcium hydroxide; group 2 had root canal dressing with 1% chlorhexidine gel and group 3, did not receive a dressing. The roots were incubated in 100% humidity at 37°C for 7 days. After removing the dressings, all canals of the experimental groups were obturated using a cold lateral condensation technique. The root surfaces of all specimens were coated with two layers of nail varnish, except for the 2 mm surrounding the apical foramen. Apical sealing ability was assessed by dye leakage method and the specimens were examined under a stereo-microscope. Dye penetrations were measured and analyzed using ANOVA and post-hoc Tukey test.

Results: Calcium hydroxide group had the least frequency of apical leakage at 2 mm level (0.46±0.40 mm), whilst chlorhexidine group showed the greatest apical leakage (0.86±0.42 mm). There was statistical difference between group 1 and 2 (P<0.05), but no statistical difference between group 1 and 3, or between groups 2 and 3 (P>0.05).

Conclusion: Intracanal calcium hydroxide medicament may decrease apical leakage of gutta-percha root fillings when AH26 sealer is used; chlorhexidine may increase the leakage.



Coronal sealing ability of three temporary filling materials

Mandana Naseri, Zohreh Ahangari, Mahyar Shahbazi Moghadam, Manijeh Mohammadian

Iranian Endodontic Journal, Vol. 7 No. 1 (2012), 30 December 2011 , Page 20-24

Introduction: Providing adequate coronal seal of temporary filling materials is critical for the success of root canal therapy. The aim of this in vitro study was to compare coronal seal ability of three restorative materials over different periods of time.

Materials and Methods: Ninety-eight molar teeth were selected. Once access cavities were prepared, teeth were divided randomly into three time groups (1 day, 1 week, and 4 weeks). Each group was then subdivided into three groups of 10 teeth. Each subgroup was restored using one of three restorative materials including Coltosol, Cavizol and Zonalin and then incubated in distilled water at 37ºC. The samples were then immersed in 2% methylene blue dye. After rinsing and drying, teeth were sectioned longitudinally and examined for dye penetration. Kruskal-Wallis and Mann Whitney U tests were used to analyze the data.

Results: All experimented materials showed increasing leakage from the 1st day to the 4th week. Zonalin showed more leakage than Coltosol and Cavizol at each time interval (P<0.05), but there was no significant difference between Coltosol and Cavizol.

Conclusion: Coltosol and Cavizol are suitable temporary materials for up to 1 week.

Microleakage comparison of four dental materials as intra-orifice barriers in endodontically treated teeth

Hamid Reza Yavari, Mohammad Samiei, Shahriar Shahi, Mohammad Aghazadeh, Farnaz Jafari, Majid Abdolrahimi, Saeed Asgary

Iranian Endodontic Journal, Vol. 7 No. 1 (2012), 30 December 2011 , Page 25-30

Introduction: The aim of this in vitro study was to compare polymicrobial microleakage of calcium enriched mixture (CEM) cement, mineral trioxide aggregate (MTA), amalgam, and composite resin as intra-orifice sealing materials.

Materials and Methods: Seventy single-rooted mandibular premolars were instrumented and obturated by cold lateral compaction technique. The teeth were randomly divided into four experimental groups according to used material: CEM, MTA, amalgam and composite resin (n=15) and two control groups (n=5). In experimental groups, 2 mm of coronal gutta-percha was removed and replaced with the study material. All the teeth were mounted in a two-chamber apparatus and the coronal portion was exposed to human saliva. The day the turbidity occurred was recorded for each sample. Data were analyzed using one-way ANOVA.

Results: The negative control group showed no leakage while the average microleakage time in the positive control group was 3.5 days. The average bacterial leakage times for amalgam, composite resin, MTA, and CEM groups were 27.42±3.6, 29.35±3.15, 52.57±2.87, and 50.42±2.73 days, respectively. There was no significant difference between CEM and MTA groups (P=0.27) and also between amalgam and composite resin groups (P=0.36). However, in term of average leakage time, MTA and CEM groups exhibited significant differences with amalgam and composite resin groups (P<0.001).

Conclusion: According to the results of the present in vitro study, in terms of coronal sealing in endodontically treated teeth, CEM and MTA are more effective than amalgam and composite resin.

An in vitro study of mesiobuccal root thickness of maxillary first molars

bahareh dadresanfar, Yasaman Ravandoust, Mohammad Najafi, Bahareh Dadresanfar

Iranian Endodontic Journal, Vol. 7 No. 1 (2012), 30 December 2011 , Page 31-35

Introduction: Understanding the internal anatomy of root canal system can significantly influence outcomes of root canal treatment. The aim of this in vitro study was to measure the thickness of mesiobuccal root at different levels in maxillary first molars. Materials and Methods: In this cross-sectional study, forty extracted human maxillary first molars were radiographed; accordingly, the mesial and distal root thicknesses of mesiobuccal (MB) roots were measured at four parallel horizontal levels. The samples were sectioned at the measured levels and then sections were scanned and saved in the computer. Buccal (B), Palatal (P), Mesial (M) and Distal (D) aspects of root thicknesses in single-canalled roots were measured. In two–canalled mesiobuccal roots, Distobuccal (DB) and Distopalatal (DP) aspects were evaluated alongside other measurements. Average radicular thickness in each aspect and each level was compared using ANOVA and t-test. Results: A total of 25 had two canals and 15 had one canal in MB root. In single-canalled roots M and D aspects were the thinnest whereas in two-canalled samples, the thicknesses of DP and DB aspects were significantly less than others (P<0.001). The B and P had the greatest thicknesses in all the samples. Conclusion: The results showed that special attention should be paid to "danger zone” areas of mesiobuccal maxillary first molar roots in order to avoid technical mishaps.

Case Report

Management of single-rooted maxillary central incisor with two canals: A case report

anantanarayanan krishnamurti, natanasabapathy velmurugan, suresh nandini

Iranian Endodontic Journal, Vol. 7 No. 1 (2012), 30 December 2011 , Page 36-39

The aim of this study was to report the endodontic management of right maxillary central incisor having two canals with Vertucci canal configuration type IV. Internal morphology of root canals is variable and often complex. Therefore, to achieve a technically satisfactory endodontic outcome, the clinician must have adequate knowledge of the internal canal morphology and its variations in order to debride and obturate the root canal system thoroughly.

Surgical alternative for treatment of vertical root fracture: A case report

Emmanuel João Nogueira Leal da Silva, Gustavo Romão dos Santos, Renato Liess Krebs, Tauby de Souza Coutinho-Filho

Iranian Endodontic Journal, Vol. 7 No. 1 (2012), 30 December 2011 , Page 40-44

Vertical root fracture (VRF) has been a great challenge in dentistry; most fractures often result in tooth extraction. Inflammation of tissues around the fractured root is the main reason for tooth extraction. Based on the strategic importance of some fractured teeth, treatment may be necessary and often complicated. However, performing a proper repair or even splinting the fractured segments may result in tooth preservation. Accordingly, in this case we report a new method for fractured tooth preservation. The surgical exposition of the fracture tooth was carried out through the radicular portion of the element via ultrasonic preparation, filling with composed resin and a synthetic hydroxyapatite graft. All these were performed around the tooth which received five sections of low-power laser. The patient was followed for two years with no signs or symptoms of inflammation and gingival recession. In conclusion, the used treatment protocol could be considered as a promising approach for VRF treatment, especially in cases where there is advanced or moderate bone loss in the surrounding sites of the fractured tooth.


Published endodontic articles in PubMed-indexed journals from Iran

Saeed Asgary, Sedigeh Sabbagh, Mohammad Jafar Eghbal

Iranian Endodontic Journal, Vol. 7 No. 1 (2012), 30 December 2011 , Page 1-4

Introduction:  The aim of this survey was to illustrate statistical information about endodontic research published in pubmed index journals from the different universities of Iran.

Materials and Methods: A PubMed search was performed to retrieve the endodontic publications of authors affiliated to different universities of Iran. Abstracts were reviewed and unrelated articles were omitted. Citation of each article was obtained from Scopus and Google scholar databases. Data were extracted and transferred to Microsoft Excel to determine the related scintometric indicators.

Results: A total of 307 papers were found according to the defined criteria which shows considerable increase from 2 papers in 1992 to 54 in 2011. Majority of the papers (48%) were related to in vitro studies; this number was 33% for in vivo surveys. Meta-analysis, systematic review and clinical trial constituted 10% of all publications. The average number of authors for the overall publications was 3.84; majority of articles (20%) were written by three authors. The average number of citation from Google Scholar (8.93) was higher than those from Scopus (4.74). Most of the endodontic articles originated from the Mashad University of Medical Sciences (16%).

Conclusion: Endodontic publication from different universities in Iran has considerably in creased, showing that research in becoming more important.