Abstract：
:The anatomy of third molars has been described as unpredictable. However restorative, prosthetic, and orthodontic considerations often require endodontic treatment of third molars in order for them to be retained as functional components of the dental arch. The purpose of this study was to investigate and characterize the anatomy of maxillary and mandibular third molars. One hundred fifty maxillary and 150 mandibular extracted third molars were vacuum-injected with dye, decalcified, and made transparent. The anatomy of the root canal system was then recorded. Seventeen percent of mandibular molars had one root (40% of which contained two canals), 77% had two roots, 5% had three roots, and 1% had four roots. Teeth with two roots exhibited highly variable canal morphology, containing from one to six canals, including 2.2% that were "C-shaped." Fifteen percent of maxillary molars had one root, 32% had two roots, 45% had three roots, and 7% had four roots. Teeth with one root demonstrated the most unusual morphology, with the number of canals varying from one to six. An in vivo study of the canal morphology of treated third molars is suggested to provide the practitioner with an understanding of the clinical implications of third molar root anatomy.
journal_name
J Endodjournal_title
Journal of endodonticsauthors
Sidow SJ,West LA,Liewehr FR,Loushine RJdoi
10.1097/00004770-200011000-00011keywords:
subject
Has Abstractpub_date
2000-11-01 00:00:00pages
675-8issue
11eissn
0099-2399issn
1878-3554pii
S0099-2399(05)60815-1journal_volume
26pub_type
杂志文章abstract：:The diameter of nine sizes of three brands of endodontic spreaders was measured at D1 and D16 and compared with corresponding sizes of six brands of accessory gutta-percha cones. Two evaluators independently measured 20 randomly selected samples of each size of finger spreader and accessory gutta-percha cone. A standa...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/S0099-2399(07)80153-1
更新日期：1991-01-01 00:00:00
abstract：:Amalgam cores with cemented dowels are commonly used to restore endodontically treated teeth. These restorations were widely studied for their mechanical properties; however, less is known about their sealing ability. The effect of the cement type used for the dowel and that of a bonding agent application were studied...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/00004770-200104000-00015
更新日期：2001-04-01 00:00:00
abstract：INTRODUCTION:The study compared Twisted File (TF) with 3 traditionally manufactured systems to determine whether changes in the manufacturing process improved the cyclic fatigue resistance. METHODS:Four rotary file systems, (1) ProFile (PF), (2) Mtwo, (3) K3, and (4) TF, were tested in artificial canals with 45° and 9...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2011.12.034
更新日期：2012-04-01 00:00:00
abstract：:Ultrasonic instruments are a valuable asset for removing intraradicular posts from root canals before nonsurgical endodontic therapy. The purpose of this study was to evaluate the relative efficacy of post removal by ultrasonic and sonic devices. Fifty extracted teeth were instrumented and obturated. The canals were p...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/S0099-2399(06)80044-0
更新日期：1994-10-01 00:00:00
abstract：:Type IV matrix metalloproteinases (MMPs) are members of the family of MMPs and are thought to play an important role in degradation of extracellular components. Human pulp cells can secrete and produce these enzymes. Recent evidence shows that MMPs may play a role in pulpal inflammation. To date little is known regard...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/00004770-200111000-00007
更新日期：2001-11-01 00:00:00
abstract：:Advanced glycation end products (AGEs) have been found to play a role in inflammation and vascular complications. The receptor for AGE (RAGE) is expressed on many cells and is up-regulated during inflammation. To date, RAGE expression or its correlation with nuclear factor kappa beta (NF-kappabeta) expression has not ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2008.02.013
更新日期：2008-06-01 00:00:00
abstract：:The oral region comprises 1% of the total body area, yet it accounts for 5% of all bodily injuries. In preschool children, oral injuries make up as much as 17% of all bodily injuries. The incidence of traumatic dental injuries is 1%-3%, and the prevalence is steady at 20%-30%. The annual cost of treatment is US $2-$5 ...
journal_title：Journal of endodontics
pub_type： 杂志文章,评审
doi：10.1016/j.joen.2012.11.021
更新日期：2013-03-01 00:00:00
abstract：:The aims of this study were to identify microorganisms on the surface of gutta-percha (GP) cones using a polymerase chain reaction (PCR) and to evaluate the sterilization effect of 5.25% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX), and ChloraPrep on these bacteria. Alterations of the surface texture and physic...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2007.01.019
更新日期：2007-05-01 00:00:00
abstract：INTRODUCTION:This study aimed to evaluate the precision of electronic apex locators (EALs) in locating the apical constriction (AC) during a root canal treatment compared with a histologic evaluation of the AC as well as the effects of possible influencing factors by means of a systematic review of the literature and m...
journal_title：Journal of endodontics
pub_type： 杂志文章,meta分析,评审
doi：10.1016/j.joen.2015.08.012
更新日期：2015-11-01 00:00:00
abstract：INTRODUCTION:A major complication after endodontic treatment is persistent pain on biting or chewing. Although unsuccessful endodontic treatment can account for such pain, pain to chewing and biting can also be a result of an unsupported or propagated crown fracture. Crown fractures that extend apically result in deter...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2014.06.021
更新日期：2015-01-01 00:00:00
abstract：INTRODUCTION:The introduction of nickel-titanium (NiTi) files into clinical practice has improved the quality of canal shaping, but increasing the curvature of the root canal (or the diameter of the master instrument that prepares the full working length) could result in more transportation, straightening, and aberrati...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2011.06.030
更新日期：2011-10-01 00:00:00
abstract：INTRODUCTION:The aim was to present a novel surgical technique using virtually preplanned 3-dimensional (3D)-printed templates for guided osteotomies. These were to ensure atraumatic uncovering of a severely impacted donor tooth including guided drilling of the recipient alveolus followed by a secure autotransplantatio...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2020.07.024
更新日期：2020-07-29 00:00:00
abstract：INTRODUCTION:Interferon regulatory factor 8 (IRF8) is a critical transcription factor in innate immune responses that regulates the development and function of myeloid cells. Human periapical lesions are caused by endodontic microbial infections. However, the presence of IRF8 in human periapical lesions remains elusive...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2018.04.015
更新日期：2018-08-01 00:00:00
abstract：INTRODUCTION:An ideal root canal sealer creates a bacteria-resistant seal and exhibits antimicrobial activity, biocompatibility, and osteoconductivity. The aim of this study was to assess the effects of 3 root canal sealers on cell viability, inflammatory response, and osteogenic potential in MC3T3-E1 cells. METHODS:A...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2018.09.006
更新日期：2019-01-01 00:00:00
abstract：:The polymerase chain reaction (PCR) is an innovative nucleic acid-based assay that has the highest sensitivity of any microbiological technique for the detection of bacteria. The purpose of this study was to use PCR to detect the presence of specific species of bacteria in samples collected from two geographical locat...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/00004770-200403000-00004
更新日期：2004-03-01 00:00:00
abstract：INTRODUCTION:This study was conducted to evaluate and compare the fracture resistance of roots obturated with various contemporary canal-filling systems. METHODS:Fifty single-rooted extracted mandibular premolars were decoronated to obtain 13-mm root segments. Ten roots were left unprepared and unfilled (negative cont...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2011.08.008
更新日期：2011-11-01 00:00:00
abstract：:The purpose of this study was to compare the reinforcement and strengthening ability of Resilon, gutta-percha, and a self-curing composite resin (Bisfil 2B) in endodontically treated roots of immature teeth. Sixty single rooted teeth were divided into five groups of 12 teeth each. Teeth in all groups except the negati...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2005.08.001
更新日期：2006-04-01 00:00:00
abstract：:Primary intraosseous salivary gland tumors are rare, with mucopidermoid carcinoma being the most frequent histotype. The authors present a case of adenoid cystic carcinoma, located in the mandibular incisor region, associated with pain. Endodontic treatment resulted in increased pain and progressive mandibular expansi...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/00004770-200012000-00026
更新日期：2000-12-01 00:00:00
abstract：:Immune and nervous systems play key roles in periapical pathosis; however, their spatial associations, which may be a prerequisite for paracrine interactions in the progression of periapical lesions, remain to be examined. In this study we examined the distribution and frequency of spatial associations between major h...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2006.08.014
更新日期：2007-02-01 00:00:00
abstract：:The purpose of this study was to evaluate the effect of citric acid and EDTA solutions on the microhardness and the roughness of human root canal dentin. Forty-five human teeth sectioned longitudinally were used. Specimens were randomly divided into three groups of 30 teeth each and were treated as follows: (a) one mo...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/01.don.0000136212.53475.ad
更新日期：2005-02-01 00:00:00
abstract：INTRODUCTION:This clinical study was conducted to measure the endotoxin levels in infected root canals (RCs) and exudates related to acute apical abscesses (AAAs). In addition, the effectiveness of RC procedures in reducing the endotoxin levels in RCs was monitored. METHODS:Paired samples of infected RCs and exudates ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2013.10.008
更新日期：2014-02-01 00:00:00
abstract：INTRODUCTION:Alkaline phosphatase (ALP) plays an important role in inducing mineralization events in the dental pulp. This study investigated and compared the ALP levels in healthy and inflamed pulp in young and old human pulp. METHODS:Tissue samples were collected from young (<30 years) and old (>60 years) donors. In...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2015.10.003
更新日期：2016-01-01 00:00:00
abstract：INTRODUCTION:This study aimed at evaluating the bond strength to root dentin of 2 mineral trioxide aggregate (MTA)-based sealers (Endo-CPM sealer and MTA Fillapex) and of 1 epoxy resin-based sealer (AH Plus sealer). METHODS:Forty-five extracted human teeth with single roots were prepared by using the step-back techniq...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2011.10.018
更新日期：2012-02-01 00:00:00
abstract：:The denaturation temperature (T(d)) of dentin collagen in mineralized versus demineralized teeth was examined as a function of dentin age and the extent of dehydration. Using differential scanning calorimetry, T(d) of mineralized dentin was shown to be between 160 degrees C to 186 degrees C, depending on whether it wa...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2005.10.062
更新日期：2006-07-01 00:00:00
abstract：INTRODUCTION:The aim of this study was to compare the shaping ability of 4 different nickel-titanium systems, considering their variation in alloy treatment, kinematics, and design, used to prepare canals with severe curvature using micro-computed tomographic analysis. METHODS:Thirty-two mesial roots of mandibular mol...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2019.02.018
更新日期：2019-06-01 00:00:00
abstract：:Ninety-six human molars were accessed. After flattening of the occlusal surface and removal of the apical two-thirds of the roots, the remaining canal space was instrumented by conventional methods. The teeth were divided into six groups of 15 teeth with three positive and three negative controls. The six experimental...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/S0099-2399(06)80078-6
更新日期：1994-12-01 00:00:00
abstract：:Apical periodontitis was induced in Wistar rats by exposing the pulp chamber of right mandibular first molars to the oral environment. Animals were killed 0, 5, 10, 15, 20, 30, 60, and 80 days after lesion induction. Microradiographic and automated image analysis showed that the lesions expanded significantly in a tim...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/00004770-200006000-00007
更新日期：2000-06-01 00:00:00
abstract：INTRODUCTION:Calcium hydroxide (CH) and nano-calcium hydroxide (NCH) as intracanal medicaments may affect the physical and chemical properties of dentin. The aim of this investigation was to evaluate the effects of CH and NCH on the microhardness and superficial chemical structure of radicular dentin. METHODS:In this ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1016/j.joen.2019.06.002
更新日期：2019-09-01 00:00:00
abstract：:Biofilm mode of growth is a strategy in microorganisms to survive harsh growth conditions. Although previous studies have established the ability of Enterococcus faecalis to survive postendodontic environmental conditions, the effect of such conditions on the ultrastructural and physiochemical features of E. faecalis ...
journal_title：Journal of endodontics
pub_type： 杂志文章
doi：10.1097/01.don.0000164855.98346.fc
更新日期：2005-12-01 00:00:00
abstract：INTRODUCTION:The purpose of this systematic review was to compare the clinical and radiographic outcomes of nonsurgical retreatment with those of endodontic surgery to determine which modality offers more favorable outcomes. METHODS:The study began with targeted electronic searches of MEDLINE, PubMed, and Cochrane dat...
journal_title：Journal of endodontics
pub_type： 杂志文章,meta分析,评审
doi：10.1016/j.joen.2009.04.023
更新日期：2009-07-01 00:00:00
