Abstract:
:The aim of this study was to investigate fracture patterns occurring when a human upper central incisor is subjected to impact loadings at various angles. A two-dimensional finite element (FE) model of the maxillary incisor and surrounding tissues was established. The structural damping factor for the tooth was then calculated and assigned to the model. Dynamic FE analysis was performed to stimulate the associated impacts. Time-dependent traumatic forces at 0 degrees, 45 degrees, and 90 degrees labially to the long axis of the tooth were applied to the model. Von Mises's equivalent stress contours within the FE models were calculated. Our results indicated that tooth damping lagged behind peak stress by 0.05 ms. In addition, we found that impact direction played an important role in terms of outcome for the fractured incisor. These results can, in part, explain the mechanisms underlying the alternative outcomes when upper incisors are subjected to impact.
journal_name
J Endodjournal_title
Journal of endodonticsauthors
Huang HM,Ou KL,Wang WN,Chiu WT,Lin CT,Lee SYdoi
10.1097/01.don.0000157992.29221.41keywords:
subject
Has Abstractpub_date
2005-10-01 00:00:00pages
723-7issue
10eissn
0099-2399issn
1878-3554pii
S0099-2399(06)61093-5journal_volume
31pub_type
杂志文章abstract::Pulp regeneration is a biologic process occurring under specific circumstances. An endodontic treatment modality to accomplish pulp regeneration has emerged based on the response of undifferentiated cells that are often referred to as stem cells. The treatment itself is currently empirical based on clinicians' thought...
journal_title:Journal of endodontics
pub_type: 杂志文章,评审
doi:10.1016/j.joen.2014.01.017
更新日期:2014-04-01 00:00:00
abstract:INTRODUCTION:Nonequilibrium plasma has been reported to effectively kill Enterococcus faecalis in endodontic biofilm compared with chlorhexidine digluconate (CHX). The purpose of this study was to evaluate the antimicrobial in vitro activity of modified nonequilibrium plasma with CHX against E. faecalis and multispecie...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2013.06.027
更新日期:2013-11-01 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:The aim was to assess the association of inducible costimulator (ICOS) and ICOS ligand with bone destruction in apical periodontitis (AP). METHODS:Specimens from patients presenting with AP were obtained during apicoectomy and subjected to histopathologic analysis and molecular assessment of ICOS/ICOS lig...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2019.03.018
更新日期:2019-07-01 00:00:00
abstract::Inflammatory myofibroblastic tumors (IMTs) are rare. IMTs of the head and neck occur in all age groups, from neonates to old age, with the highest incidence occurring in childhood and early adulthood. An IMT has been defined as a histologically distinctive lesion of uncertain behavior. This article describes an unusua...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2015.09.006
更新日期:2015-12-01 00:00:00
abstract::Various classes of immunoglobulins have been found in human periapical lesions. The specificity of secreted antibodies against antigens egressing from the root canal system has yet to be thoroughly investigated. The purpose of this study was to test the specificity of antibodies present in human periapical lesions. Hu...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/S0099-2399(06)81923-0
更新日期:1991-05-01 00:00:00
abstract::This study compared a tapered, calibrated spreader/plugger instrument (M-series) to noncalibrated spreaders and pluggers in achieving apical condensation of gutta-percha in 20 single-rooted human teeth. The distances between the tip of the instruments and the tip of the master gutta-percha were measured. Results showe...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/S0099-2399(06)80680-1
更新日期:1993-04-01 00:00:00
abstract:INTRODUCTION:Proteinases play pivotal roles in Candida albicans infections. Although the yeast can colonize the pulpal environment, there is no information about the enzymatic profile of this organism. This in vitro study aimed to determine the proteolysis levels and to investigate differences in the expression of aspa...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2015.01.012
更新日期:2015-06-01 00:00:00
abstract:INTRODUCTION:The dental pulp is highly vascularized and innervated tissue that is uniquely designed, being highly biologically active, while being enclosed within the calcified structure of the tooth. It is well-established that the dental pulp vasculature is a key requirement for the functional performance of the toot...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2020.06.033
更新日期:2020-09-01 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::Increased levels of interleukin-1 (IL)-1, tumor necrosis factor-alpha (TNF-alpha), IL-6, and prostaglandin E2 (PGE2) have been detected in inflamed pulp tissue. To gain further insight into the molecular pathogenesis of pulpitis, we investigated the effects of IL-1alpha or TNF-alpha and PGE2, either alone or in combin...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1097/00004770-200203000-00013
更新日期:2002-03-01 00:00:00
abstract:INTRODUCTION:A 3-antibiotic combination (3Mix) has been widely used in regenerative endodontics. Recent studies recommend that a safe concentration of 3Mix is in the range of 0.39 μg/mL and 1 mg/mL because higher concentrations may limit tissue regeneration. The aim of this study was to determine the regenerative capac...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2013.09.027
更新日期:2014-03-01 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:INTRODUCTION:Alkaline-tolerant bacteria in primary infected root canals could have enhanced survival capacity against antimicrobials commonly used in root canal treatment. The aims of this study were to isolate and characterize alkaline-tolerant bacteria before endodontic treatment (S1), after chemomechanical root cana...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2014.12.003
更新日期:2015-04-01 00:00:00
abstract:INTRODUCTION:Prilocaine plain has a high pH and concentration (4%), which could decrease the pain of injection and increase success. The purpose of this study was to compare pain associated with anesthetic solution deposition and the degree of pulpal anesthesia obtained with the combination of prilocaine and lidocaine ...
journal_title:Journal of endodontics
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.joen.2018.01.004
更新日期:2018-05-01 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:Culture-independent studies have revealed a broad spectrum of oral bacterial taxa that may be associated with disease. This study investigated the prevalence of three new candidate oral pathogens: Prevotella baroniae, Prevotella multisaccharivorax, and as-yet-uncultivated Bacteroidetes oral clone X083 in p...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2009.05.033
更新日期:2009-10-01 00:00:00
abstract::Twenty-one teeth with clinically asymptomatic periapical pathosis (class 3) were extracted and the isolation, identification, and localization of bacteria in the root apex were examined. Mixtures involving several bacteria were isolated from more than 60% of the cases. Scanning electron microscopy revealed bacterial m...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/S0099-2399(07)80216-0
更新日期:1990-11-01 00:00:00
abstract:INTRODUCTION:Mineral trioxide aggregate (MTA) and calcium silicate (CS) cements exhibit acceptable levels of cytocompatibility. The aim of the present study was to evaluate MTA and CS cement genotoxicity in a human osteosarcoma cell line (MG63). METHODS:A mitochondrial colorimetric assay was used to evaluate the MG63 ...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2010.03.039
更新日期:2010-07-01 00:00:00
abstract::Plasminogen activator converts plasminogen to plasmin, and plasmin activates the latent matrix metalloproteinases. Tissue plasminogen activator (t-PA) is one of the important proteolysis factors present in human inflamed tissues. However, few studies reported on the mechanisms of tissue destruction via a t-PA proteoly...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1097/00004770-200302000-00007
更新日期:2003-02-01 00:00:00
abstract:INTRODUCTION:The purpose of this study was to compare the efficacy of the cutting ability of two different instruments, concerning changes in the dentin thickness removed and root canal volume, by using multislice computed tomography scanning. METHODS:Thirty single-rooted mandibular premolars were divided into two equ...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2011.03.036
更新日期:2011-08-01 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::Orthodontic tooth movement has been implicated in secondary changes to the dental pulp. The purpose of this study was to correlate the effects of orthodontic tooth movement on the dental pulp by histomorphometric parameters. Four groups, each consisting of 36 male adult Sprague-Dawley strain rats, were studied with di...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/S0099-2399(06)81034-4
更新日期:1993-01-01 00:00:00
abstract::The aim of this study was to measure root-dentin microhardness after instrumentation with two types of files and using irrigation with 2.5% sodium hypochlorite. Thirty roots were instrumented with irrigation: 10 roots had the pulp extirpated only; 10 roots were instrumented with stainless steel files, and 10 roots wer...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1097/00004770-200204000-00012
更新日期:2002-04-01 00:00:00
abstract:INTRODUCTION:Pulp capping materials allow healing of injured pulp with a layer of reparative dentin. Glucose is needed to cure the injured area. Glucose is transported by glucose transporter (Glut) 2 and Glut4, which are transmembrane proteins that act as gatekeepers. We hypothesized that the transport of glucose via G...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2019.10.003
更新日期:2020-01-01 00:00:00
abstract:INTRODUCTION:The purpose of this study was to compare centering ability and apical canal transportation of K-files (KF), ProGlider (PG), and G-Files (GF) after glide path enlargement in curved canals by using micro-computed tomography. METHODS:Thirty canals each were randomly assigned to KF, GF, and PG. Teeth were sca...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2016.04.005
更新日期:2016-07-01 00:00:00
abstract::This study sought to evaluate the influence of apical enlargement on the sealing ability of vertical compaction. Sixty anterior teeth were used. Half of these teeth were prepared to a size 25 file and the other half to a size 40 file. Then vertical compaction was performed. Apical microleakage was determined using pre...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/S0099-2399(06)80091-9
更新日期:1994-07-01 00:00:00
abstract:INTRODUCTION:The inferior alveolar nerve (IAN) injection is 1 of the most commonly administered and useful injections in the field of dentistry. Practitioners use intraoral anatomic landmarks, which vary greatly among patients. The objective of this study was to assist practitioners by identifying a range of normal var...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2015.12.009
更新日期:2016-03-01 00:00:00
abstract::Previous dye leakage studies have shown that mineral trioxide aggregate leaks significantly less than other commonly used root-end filling materials. This study determined the time needed for Staphylococcus epidermidis to penetrate a 3-mm thickness of amalgam, Super-EBA, Intermediate Restorative Material (IRM), or min...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/s0099-2399(06)80433-4
更新日期:1995-03-01 00:00:00
abstract:INTRODUCTION:The aim of this study was to evaluate porcine palatal mucosa dissolution by sodium hypochlorite (NaOCl) with or without an auxiliary dissolving agent containing glycocholic acid and a mixture of surfactants (Keratobacter [KB]; Saint Joseph DID, Valencia, Spain). METHODS:One hundred forty samples were obta...
journal_title:Journal of endodontics
pub_type: 杂志文章
doi:10.1016/j.joen.2018.01.007
更新日期:2018-05-01 00:00:00