Surgical management of a failed internal root resorption treatment: a histological and clinical report

This article presents the successful surgical management of a failed mineral trioxide aggregate (MTA) orthograde obturation of a tooth with a history of impact trauma and perforated internal root resorption. A symptomatic maxillary lateral incisor with a history of perforation due to internal root resorption and nonsurgical repair using MTA was referred. Unintentional overfill of the defect with MTA had occurred 4 yr before the initial visit. The excess MTA had since disappeared, and a radiolucent lesion adjacent to the perforation site was evident radiographically. Surgical endodontic retreatment was performed using calcium enriched mixture (CEM) cement as a repair material. Histological examination of the lesion revealed granulation tissue with chronic inflammation, and small fragments of MTA encapsulated within fibroconnective tissue. At the one and two year follow up exams, all signs and symptoms of disease had resolved and the tooth was functional. Complete radiographic healing of the lesion was observed two years after the initial visit. This case report illustrates how the selection of an appropriate approach to treatment of a perforation can affect the long term prognosis of a tooth. In addition, extrusion of MTA into a periradicular lesion should be avoided.

scientometric study of pubmed-indexed endodontic articles: a comparison between Iran and other regional countries

Based on Iran's 20-year prospective national vision document, Iran may be seen as the most developed country in science and technology in the region by 2025. In this report, bibliometric indicators are used to compare the research productivity in endodontics between Iran and 28 selected Asian countries. Medical Subject Headings keyword-searching of PubMed up to 2012 was conducted to compare the scientific publications in Iran and neighboring countries [Middle East, Middle Asia, Caucasus and EMRO countries]. Highest 5 PubMed-indexed endodontic journals were also searched to retrieve the number of published articles of the top five countries. Data were extracted, tabulated and compared to identify the ranks as well as trends. The results confirm that there are many differences in scientific endodontic publications between the studied countries; Iran ranked second in endodontic research productivity compared to Turkey in 2011. However, Iran attained first place in 2010 as well as the most positive publication trend in PubMed-indexed endodontic journals. Although Iran was in second rank in the region last year, the positive trend in published endodontic research papers is considered a sign of future success in acquiring Iran's vision

Published endodontic articles in PubMed-indexed journals from Iran

The aim of this survey was to illustrate statistical information about endodontic research published in pubmed index journals from the different universities of Iran. 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. 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. The 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%]. Endodontic publication from different universities in Iran has considerably increased, showing that research is becoming more important

Comparison of bacterial and dye microleakage of different root-end filling materials

The provision of an effective apical seal is an essential factor when choosing an appropriate material for success of root-end surgeries. Root-end resection, preparation and obturation should provide an adequate apical seal. The aim of this in vitro study was to investigate bacterial and dye microleakage of four different root-end filling materials and compare the efficacy of these two methods. Fifty-six single-rooted teeth with intact and straight roots were randomly assigned into four study groups of 12 each and two control groups of three each. After decoronation, root canals were prepared up to file size #40 using step back technique; then, they were filled with gutta-percha and AH26 sealer. Root-ends were resected 3 mm above the root-end and 3 mm deep cavities were prepared. Root-end cavities were filled with amalgam, Root Mineral Trioxide Aggregate [Root MTA], White ProRoot MTA [WMTA], and calcium enriched mixture [CEM] cement. Bacterial leakage was investigated in Trypticase Soy Broth [containing Enterococcus faecalis] after 70 days and 1% methylene blue dye leakage was assessed after 72 hours. Complete dye leakage was checked using stereomicroscope [[x]40]. Data were statistically analyzed using Fisher Exact test. For pair comparison between the two methods Kapa agreement was utilized. After 70 days there was 100% bacterial leakage in amalgam, and CEM cement, 91.7% in WMTA, and 75% in Root MTA. This difference was not significantly different. The difference in complete dye leakage was also not significant [WMTA and CEM cement 16.7%, Amalgam and Root MTA 33.3%]. There was no significant measure of agreement between dye and bacterial penetration along root-end fillings. CEM cement was not significantly different from currently used retrofilling materials e.g. WMTA

Microleakage of CEM cement in two different media

Sealing ability of root-end filling materials is of great importance. It can be investigated by measuring microleakage. The purpose of this in vitro study was to evaluate microleakage of calcium enriched mixture [CEM] cement in two different media including phosphate buffer solution [PBS] and distilled water. Twenty single-rooted human teeth were selected. All teeth were root-end filled with CEM cement. Samples were divided into two groups of 10 each and were placed in PBS or distilled water. The microleakage was measured after 12 and 24 h, 14 and 30 days with Fluid Filtration device. Data were statistically analyzed by repeated measures test. Sealing ability of CEM cement was significantly superior in PBS compared to distilled water [P<0.05]. This study also showed that time had no significant effect on the sealing ability of CEM cement. Media can significantly affect the microleakage of CEM cement. PBS can provide more phosphorous ions for hydroxyapatite formation of CEM cement; therefore, CEM cement can seal more effectively with PBS

Coronal and apical sealing ability of a new endodontic cement

This in vitro study aims to evaluate the coronal and apical sealing ability of gutta-percha [GP] root filling used with either mineral trioxide aggregate [MTA], new endodontic cement [NEC] or AH26 as filler/sealers. Forty eight single-rooted extracted teeth were selected, decoronated and then instrumented. Samples were randomly divided into three experimental [n=12] and two control groups [n=6]. In group 1, root canals were filled using lateral condensation technique [L]; while single cone technique [S] was used for groups 2 and 3. AH26, MTA and NEC were the root canal sealer/fillers in groups 1, 2 and 3, respectively. Samples were immersed in 1% methylene-blue dye and then independently centrifuged apically and coronally. The roots were split longitudinally and linear extent of dye penetration was measured with a stereomicroscope from apical and coronal directions. Data were analyzed using One-way ANOVA and T-test. No statistical differences in mean apical dye penetration between groups LGP/AH26, SGP/MTA and SGP/NEC were found; SGP/NEC group showed significantly less coronal dye penetration [P<0.001]. Considering the limitations of this in vitro study, it was concluded that the simple single cone technique with NEC can provide favorable coronal and apical seal

Prevalence of referred pain with pulpal origin in the head, face and neck region

This study was designed to evaluate the prevalence of referred pain with pulpal source in the head, face and neck region among patient referred to Dental school of Shahid Beheshti University MC, Tehran, Iran in 2004. In this cross-sectional study, 100 patients [55 males and 45 females] referred to oral medicine department of Shahid Beheshti Dental School evaluated via clinical and radiographic examination to seek their pain sources and sites. Inclusion criteria were report of pain and a dental clinician accomplished detection of pain origin. Exclusion criteria were non-odontogenic painful diseases, advanced periodontal disease, and substantial carious lesions. Visual analogue scale[VAS] was used to score pain intensity; meanwhile the patients were asked to mark the painful sites on an illustrated head and neck mannequin. Sixty-five percent of patients reported pain in sites which diagnostically differed from the pain source. According to statistical analysis, duration [P 0.05]. The prevalence of referred pain with pulpal origin in the head, face and neck region is moderately high which requires precise diagnosis by dental practitioners. Some hallmarks of irreversible pulpitis [e.g. spontaneous and persistent pain after elimination of stimulus] are related to pain referral

Stress distribution changes after root canal therapy in canine model: a finite element study

The fracture strength of endodontically treated teeth compared to vital ones has long been a source of controversy. It is not clear how root canal therapy affects the stress distribution in teeth. The purpose of this study was to evaluate the changes in stress distribution after root canal therapy in a human maxillary canine by finite element analysis [FEM]. Two 3D FEM models of a maxillary canine were created; one represented a virgin tooth and the other represented the same tooth after root canal therapy. A single force of 14.1 N was applied 45 degrees to horizontal plane to the center of the palatal surface; stress distribution was then analyzed in both models. SEQV [VonMises stress] analysis demonstrated an obvious decrease after root canal therapy and the regions near cementoenamel junction [CEJ] showed the highest displacement. The endodontically treated tooth demonstrated higher deflection than the vital one. Maximum stress and displacement was repeatedly found in the cervical area, hence more emphasis should be placed on the reinforcement of this region