Effect of access cavities on the biomechanics of mandibular molars: a finite element analysis.

Introduction: This study aimed to predict the fracture resistance of a mandibular first molar (MFM) with diverse endodontic cavities using finite element analysis (FEA).

Methods: Five experimental finite element models representing a natural tooth (NT) and 4 endodontically treated MFMs were generated. Treated MFM models were with a traditional endodontic cavity (TEC) and minimally invasive endodontic (MIE) cavities, including guided endodontic cavity (GEC), contracted endodontic cavity (CEC) and truss endodontic cavity (TREC).

Role-play in Endodontic Teaching: a Case Study.

Objective: To investigate the role of the application of role-play in endodontic study in improving the communication skills of Chinese dental undergraduates prior to their direct interactions with patients at the Fourth Military Medical University’s School of Stomatology, China. Methods: Students were recruited from the 5-year bachelor’s programme (n = 36) and randomly divided into six groups, and from the 8-year DDS programme (n = 10) and randomly divided into two groups to participate in the role-play training. Cases selected randomly from the case pool were distributed to the groups.

Melatonin attenuates inflammation of acute pulpitis subjected to dental pulp injury.

Acute pulpitis (AP), one of the most common diseases in the endodontics, usually causes severe pain to the patients, which makes the search for therapeutic target of AP essential in clinic. Toll-like receptor 4 (TLR4) signaling is widely involved in the mechanism of pulp inflammation, while melatonin has been reported to have an inhibition for a various kinds of inflammation. We hereby studied whether melatonin can regulate the expression of TLR4/NF-ĸB signaling in the pulp tissue of AP and in human dental pulp cells (HDPCs).

[Defects in 2061 discarded ProTaper handfiles after clinical use].

Purpose: To explore the mechanism of failure of ProTaper NiTi handfiles during root canal preparation.

Methods: A total of 2061 discarded ProTaper handfiles were collected after clinical use. The files were studied under stero-microscope to determine the type of defect.

[A micro-computed tomographic analysis of the apical anatomy of permanent three-rooted mandibular first molars].

Objective: To investigate the anatomic features of the root apexes of permanent three-rooted mandibular first molars.

Methods: A total of 122 permanent mandibular first molars of Han Chinese patients were collected. Twenty three-rooted and 25 two-rooted molars were scanned by micro-CT and then reconstructed three-dimensionally.

Two-week extrinsic stain removal efficacy of a sodium fluoride dentifrice with high cleaning silica: results from two randomized, controlled clinical trials.

Purpose: To evaluate a stannous-containing sodium fluoride dentifrice with high cleaning silica and polychelation technology (test dentifrice) compared to a currently marketed whitening dentifrice, which carries the ADA Seal of Acceptance for whitening, for its efficacy in removing existing natural stain over a 2-week period.

Methods: Two independent, randomized, positive-controlled, 2-treatment, parallel group, double-blind, 2-week studies with identical protocols were conducted in China. At baseline, subjects received an oral soft tissue (OST) examination followed by a Lobene stain examination.

The desensitizing efficacy of a novel stannous-containing sodium fluoride dentifrice: an 8-week randomized and controlled clinical trial.

Purpose: To assess the efficacy of a novel stannous-containing dentifrice in the reduction of dentin hypersensitivity when compared to a marketed positive control dentifrice.

Methods: An 8-week, single-center, randomized, parallel group, two-treatment, double-blind clinical study was conducted in a generally healthy adult population with moderate thermal and tactile dentin hypersensitivity. A total of 60 adults were enrolled into the study.

[The use of dental papillae cells and millipore filter for bioengineered dentin].

Objective: To observe the ability of SD rat dental papillae cells forming dentin-like structure induced by millipore filter combined with transforming growth factor-β(1) (TGF-β(1)).

Methods: The first passage SD rat dental papillae cells were enzymatically dissociated and centrifuged to obtain a cell mass. The cell mass was seeded on the millipore filter combined with TGF-β(1).

Novel immunohistochemical monoclonal antibody against human XBP-1.

The X-box binding protein-1(XBP-1) is a 29 kDa protein belonging to the basic region/leucine zipper (bZIP) family of transcription factors. Previous studies showed that XBP-1 mediated a wide range of responses in B-cell differentiation, unfolded protein response (UPR), and tumorigenesis. For these reasons, it is believed that XBP-1 would be a novel therapeutic target in some pathogenic processes.

Stress distribution in molars restored with inlays or onlays with or without endodontic treatment: a three-dimensional finite element analysis.

Statement Of Problem: Previous research into the strength of endodontically treated or vital teeth restored with inlays or onlays has not determined which restoration method and material provide the most favorable stress distribution upon loading.

Purpose: The purpose of this study was to calculate the von Mises stresses in a mandibular first molar using a 3-dimensional (3-D) finite element model. Models compared endodontically treated and vital teeth, a variety of restorative materials, and the use of either inlays or onlays to restore teeth.

[Establishment and application of an in vitro model for apatite crystal mineralization].

Objective: To establish an in vitro model for the apatite crystal mineralization. To evaluate the influences of bovine serum albumin (BSA) and fluoride to the mineralization of apatite crystal.

Methods: The model was constructed using cation selective membrane (CMV) and dialysis membrane.

[Influence of luxS of Streptococcus mutans on biofilm of dental plaque].

Objective: To construct luxS mutant aften luxS gene of Streptococcus mutans (S. mutans) was knocked out, and examine their ability of biofilm formation.

Methods: A recombinant plasmid containing the flanking fragment of luxS of S.