Abstract：
INTRODUCTION:Many studies have investigated the morphology of the mandibular molar, but the prevalence of the middle mesial (MM) canal in the mesial root of the mandibular molar is still the subject of controversy. In addition, in previous literature, a true MM canal has not been clearly distinguished from an isthmus between the mesiobuccal and mesiolingual canals. Therefore, the objectives of this study were 2-fold: METHODS: Ninety limited field of view cone-beam computed tomographic scans were observed. One hundred twenty-two mature mandibular first and second molars with no previous root canal treatment, no root resorption, and intact crowns were retrospectively evaluated. Data regarding the sex, age, presence of MM canals, and number of root canals in the mesial root were recorded. RESULT:Of the 122 teeth, 20 (16.4%) had true MM canals. The prevalence of MM canals was 26% in first molars and 8% in second molars (P < .05). The frequency of isthmi in the mesial roots was 64.7%. The frequency of isthmi was higher in second molars, but the difference was not statistically significant (P > .05). CONCLUSIONS:This study showed a high prevalence of mandibular molars with MM canals or isthmi. The detection and biomechanical cleaning of these areas during nonsurgical or surgical root canal treatment are critical.
journal_name
J Endodjournal_title
Journal of endodonticsauthors
Tahmasbi M,Jalali P,Nair MK,Barghan S,Nair UPdoi
10.1016/j.joen.2017.02.008subject
Has Abstractpub_date
2017-07-01 00:00:00pages
1080-1083issue
7eissn
0099-2399issn
1878-3554pii
S0099-2399(17)30248-0journal_volume
43pub_type
杂志文章abstract：:The authors reviewed the literature evaluating the antibacterial effectiveness of intracanal medicaments used in the management of apical periodontitis. A PICO (problem, intervention, comparison, outcome) strategy was developed to identify studies dealing with calcium hydroxide, phenolic derivatives, iodine-potassium ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/01.don.0000129959.20011.ee
更新日期：2004-10-01 00:00:00
abstract：:The purpose of this study was to evaluate the effect of occlusal load on the integrity of root canal obturation. Maxillary anterior teeth were cleaned, shaped, and obturated with either gutta-percha (GP)/AH Plus or Resilon/Epiphany. Afterwards, teeth were placed under 100 N force at 2 Hz for 22 hours in a 37 degrees C...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2008.01.022
更新日期：2008-04-01 00:00:00
abstract：:With the recent influx of osseointegrated endosseous implants in dentistry, attention has been drawn away from using endodontic stabilizers as a means of stabilizing and retaining teeth. It is our opinion that endodontic stabilizers should be considered in the treatment planning of seemingly nonretainable teeth. They ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/S0099-2399(06)81268-9
更新日期：1992-05-01 00:00:00
abstract：INTRODUCTION:The purpose of this study was to evaluate the antibacterial efficacy of silver nanoparticles (AgNPs) as an irrigant or medicament against Enterococcus faecalis biofilms formed on root dentin. METHODS:Dentin sections were inoculated with E. faecalis for 4 weeks to establish a standard monospecies biofilm m...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2013.08.022
更新日期：2014-02-01 00:00:00
abstract：:Bisphosphonates are commonly used in medicine to maintain bone density in patients with certain nonneoplastic diseases or cancers. A serious adverse effect of bisphosphonates that has substantial dental significance is osteonecrosis that appears to uniquely affect the mandible and maxilla without occurring in other bo...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/01.don.0000186481.96169.cd
更新日期：2005-11-01 00:00:00
abstract：:The sealing properties of three temporary restorative materials, Cavit, IRM, and a polycarboxylate-based cement, Ultratemp Firm, were investigated in vitro. Standardized access cavities were prepared in 45, intact, extracted, human molars. The teeth were randomly assigned to three groups and the access openings filled...
journal_title：Journal of endodontics
pub_type： 临床试验,杂志文章,随机对照试验
doi：10.1097/01.don.0000121610.63000.f2
更新日期：2004-08-01 00:00:00
abstract：:The objective of this study was to assess and compare canal blockages and apical extrusion of dentin debris during canal shaping with eight preparation techniques. A total of 208 canals in extracted human teeth were prepared by one operator using one type of file. The techniques included were standardized, stepback wi...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/s0099-2399(06)80443-7
更新日期：1995-03-01 00:00:00
abstract：:The occurrence of Enterococcus faecalis in root canals of previously root filled teeth with apical periodontitis requiring retreatment was studied in Lithuanian patients. Twenty-five asymptomatic teeth were included in the study. Avoiding contamination microbiological samples were taken from the canals before and afte...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/00004770-200010000-00004
更新日期：2000-10-01 00:00:00
abstract：INTRODUCTION:Complementary methods of anatomic diagnosis, including cone-beam computed tomographic (CBCT) imaging, may be useful in the diagnosis of mesiobuccal (MB) canals of maxillary molars. METHODS:Thirty-five maxillary first molars were subjected to ex vivo analysis and 4 CBCT protocols: i-CAT Classic (Imaging Sc...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2016.12.011
更新日期：2017-05-01 00:00:00
abstract：:The finite element method was used to compare stresses along the inner canal wall in four two-dimensional models of an average maxillary central incisor. The four models evaluated were an intact incisor, an endodontically treated incisor, an endodontically treated crown-restored incisor, and a cylindrical post and cro...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/S0099-2399(06)81210-0
更新日期：1992-11-01 00:00:00
abstract：:Irreversibly inflamed pulp (IIP) constitutes both a pathophysiologic and a diagnostic challenge. Gingival crevicular fluid (GCF) samples were obtained with Periopaper strips from IIP and adjacent and contralateral teeth for interleukin-8 (CXCL8) and tumor necrosis factor-alpha (TNF-alpha) measurements. Pain intensity ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2007.10.022
更新日期：2008-02-01 00:00:00
abstract：:The cleaning capacity of manual and rotary instrumentation techniques in mesial-distal flattened canals was studied by morphometric analysis. Twenty human mandibular incisors were divided into two groups of 10 teeth each: group 1, crown-down technique with rotary instrumentation using ProFile .04; group 2, crown-down ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/00004770-200205000-00004
更新日期：2002-05-01 00:00:00
abstract：INTRODUCTION:The purpose of this study was to assess the ex vivo torsional performance of a novel rotary system in small root canals after 2 different glide path preparations. METHODS:Each independent canal of 8 mesial roots of mandibular molars was randomly assigned to achieve a reproducible glide path with a new set...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2016.10.034
更新日期：2017-03-01 00:00:00
abstract：INTRODUCTION:Apical surgery is frequently indicated in maxillary first molars. Occasionally, a vascular anastomosis in the lateral maxillary sinus wall can be observed during surgery. The aim of this study was to examine the distance between the vascular bone channel (VBC) and the root apices of maxillary first molars ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2019.09.004
更新日期：2019-12-01 00:00:00
abstract：INTRODUCTION:The purpose of this study was to evaluate the incidence and mode of WaveOne (Dentsply Tulsa Dental Specialties, Tulsa, OK) instrument defects after single use at different endodontic clinics. METHODS:A total of 438 WaveOne instruments were collected after clinical use from the 4 specialist clinics over a ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2015.10.008
更新日期：2016-02-01 00:00:00
abstract：:The aim of this laboratory based study was to determine the shaping ability of Lightspeed nickel-titanium rotary instruments in simulated root canals. A total of 40 canals with four different shapes in terms of angle and position of curve were prepared with Lightspeed instruments using the stepback technique recommend...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/S0099-2399(97)80347-0
更新日期：1997-12-01 00:00:00
abstract：INTRODUCTION:In recent years, the inflammasome has been determined to play an important role in inflammatory diseases. However, the role of the inflammasome in pulpitis remains unclear. Absent in melanoma 2 (AIM2) is a type of inflammasome that recognizes cytosolic double stranded DNA and forms a caspase-1-activating i...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2013.07.003
更新日期：2013-11-01 00:00:00
abstract：:The objective of this study was to compare the effectiveness of F-files and ultrasonics to remove the smear layer from instrumented root canals when irrigated with sodium hypochlorite and EDTA. Sixty healthy human premolar teeth were instrumented with ProTaper file series to F3, and the canals were enlarged with Profi...
journal_title：Journal of endodontics
pub_type： 杂志文章,随机对照试验
doi：10.1016/j.joen.2008.07.006
更新日期：2008-10-01 00:00:00
abstract：INTRODUCTION:We evaluated the effect of various antimicrobials used in endodontic regeneration on a 3-week-old Enterococcus faecalis biofilm. METHODS:E. faecalis biofilm was grown on standardized dentin samples for 3 weeks. Infected dentin samples were randomized into 8 experimental groups (n = 8) and treated with cal...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2015.09.023
更新日期：2016-02-01 00:00:00
abstract：:The aim of this study was to evaluate the time required by four different root canal medications coupled with the temporary filling material Cavit (ESPE, Seefeld, Germany) to prevent penetration of bacteria into the root canal. There were 145 roots prepared in a standardized manner. Four groups with 15 samples each we...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2005.10.023
更新日期：2006-02-01 00:00:00
abstract：:This study evaluated the effect of three post surface treatments on quartz-fiber post (a) retention and (b) morphology. A control group was not treated. Different treatments were performed for the other posts: silanization; etching by hydrofluoric acid 9.5%; sandblasting with 50 microm Al2O3. Two specimens of each gro...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2006.10.015
更新日期：2007-03-01 00:00:00
abstract：INTRODUCTION:This study compared the efficacy of a reciprocating single-instrument system and a rotary multi-instrument system followed by a supplementary approach with a finishing instrument in removing the filling material from curved canals during retreatment. METHODS:Forty mesial canals from extracted mandibular m...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2016.04.007
更新日期：2016-07-01 00:00:00
abstract：:The current external inflammatory root resorption treatment protocol, which uses calcium hydroxide dressing, usually comprises multiple and long-term applications. In addition to the need for multiple appointments for calcium hydroxide replacement, the long-term maintenance of this compound in the root canal weakens d...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2015.03.019
更新日期：2015-09-01 00:00:00
abstract：:This case series reports the outcomes of 8 patients (ages 9-14 years) who presented with 9 immature permanent teeth with pulpal necrosis and apical periodontitis. During treatment, 5 of the teeth were found to have at least some residual vital tissue remaining in the root canal systems. After NaOCl irrigation and medi...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2008.03.023
更新日期：2008-07-01 00:00:00
abstract：INTRODUCTION:This study aimed to evaluate the frequency of dentinal microcracks observed after root canal preparation with 2 reciprocating and a conventional full-sequence rotary system using micro-computed tomographic analysis. METHODS:Thirty mesial roots of mandibular molars presenting a type II Vertucci canal confi...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2014.02.019
更新日期：2014-09-01 00:00:00
abstract：:The purpose of treating furcal perforation is to seal the artificial communication between the endodontic space and the periradicular tissue to prevent alveolar bone resorption and damage to the periodontal ligament. These complications are not infrequent in cases of furcal and/or old perforations, which show a worse ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2008.05.019
更新日期：2008-09-01 00:00:00
abstract：INTRODUCTION:The aim of this study was to assess the root canal configurations in permanent mandibular lateral incisors (PMLIs) and the correlation between the root canal configurations of PMLIs with the appearance of a distolingual root (DLR) in permanent mandibular first molars (PMFMs) using cone-beam computed tomogr...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2017.08.027
更新日期：2018-01-01 00:00:00
abstract：:Ten extracted human maxillary first molars were selected with a variety of root curvatures. The distofacial roots were resected and the mesiofacial canals were instrumented to a size #25 K file. Three techniques were used to introduce Ca(OH)2 paste into the instrumented canals. These techniques were evaluated for thei...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/s0099-2399(06)81220-3
更新日期：1992-08-01 00:00:00
abstract：:The external cervical root resorption associated with intracoronal bleaching of pulpless teeth can be a devastating lesion. It often cannot be repaired. To prevent this problem, increasing attention has been focused on placing a barrier between the pulp chamber and the endodontic filling material. The objective of thi...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/s0099-2399(06)80822-8
更新日期：1994-06-01 00:00:00
abstract：:This study compared the quality of obturation of high- and low-temperature thermoplasticized injectable gutta-percha techniques and standard lateral condensation. A new model system was developed to more closely simulate the clinical environment. All obturations were performed in this same model which allowed direct c...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/S0099-2399(06)81863-7
更新日期：1991-06-01 00:00:00
