Preoperative Factors Associated with Anesthesia Failure for Patients Undergoing Nonsurgical Root Canal Therapy: A National Dental Practice-Based Research Network Study.

Introduction: The aim of this study was to identify preoperative factors associated with local anesthesia failure.

Methods: The National Dental Practice-Based Research Network (www.NationalDentalPBRN.

The effect of rotary instrumentation on dentin thickness in the danger zone of the MB2 canal of maxillary first molars.

The aim of this study was to measure the initial and remaining dentin thickness in the danger zone of the second mesiobuccal (MB2) canal of maxillary first molars after rotary instrumentation using cone beam computed tomography (CBCT) imaging. After determining initial dentin thickness, each sample was subjected to a standardized protocol of rotary instrumentation files: ProTaper Gold Sx Orifice Opener (maximum depth of 7 mm); Vortex Blue 15.04, 20.

Postoperative Pain after Treatment Using the GentleWave System: A Randomized Controlled Trial.

Introduction: Cleaning and shaping are necessary to allow for the delivery of irrigants and medicaments to the apical third of the canal. Standard treatment irrigation generally uses a conventional needle and some frequency of sonic activation. The GentleWave System (GWS; Sonendo, Inc, Laguna Hills, CA) combines irrigant delivery with multisonic activation.

Anatomic Analysis of Palatal Roots of Maxillary Molars Using Micro-computed Tomography.

Introduction: The morphology of the palatal root of maxillary first and second molars was analyzed and compared using micro-computed tomographic scanning.

Methods: Forty-seven extracted maxillary molars were scanned with a micro-computed tomographic device to analyze the palatal radicular dentin dimensions, canal working width, root length, canal curvature, lateral canals, and apical constriction anatomy. Quantitative data were analyzed with mean and standard deviation for first and second molars, respectively.

Mandibular Canal Location: Cone-beam Computed Tomography Examination.

Introduction: The increased use of implants and potential endodontic misadventures can lead to nerve damage. The purpose of this study was to use cone-beam computed tomography (CBCT) measurements to investigate mandibular canal (MC) location in relation to mandibular posterior teeth, the dimension of the buccal and lingual bone over the MC, the diameter of the MC, and the anterior loop location near the mental foramen.

Methods: CBCT scans from 106 patients (age, 18-69 years) were used to evaluate measurements from 636 teeth and respective MC areas.

Cone-beam Computed Tomography: Anatomic Analysis of Maxillary Posterior Teeth-Impact on Endodontic Microsurgery.

Introduction: It is imperative that the endodontic surgeon be knowledgeable of the anatomic dimensions of the surgical site. If cone-beam computed tomography is not available because of location/cost, it is prudent for the clinician to consult a knowledge base for the surgical site. An understanding of the root thickness of maxillary premolars and molars at the preferred level for root resection (3.

Electrical Pulp Testing: Sources of Error.

Introduction: Accurate identification and assessment of an inflamed or necrotic tooth is essentialfor endodontic treatment. The purpose of this research was to investigate possible sources of error associated with the use of the electric pulp tester (EPT).

Methods: Forty-six intact teeth (23 tooth pairs) in 22 patients were evaluated in vivo.

The Incidence of Furcation Region Patency in Molars Before and After Simulated Periodontal Therapy.

Purpose: To determine if there is increased bacterial communication through the furcation region in molar teeth after simulated periodontal therapy.

Methods: Sixty-five extracted first and second molars were accessed and the roots were sectioned 4 mm apical to the furcation. The canals and external suface of the root were sealed except the furcation region.

Spectrophotometric determination of irrigant extrusion using passive ultrasonic irrigation, EndoActivator, or syringe irrigation.

Introduction: Sodium hypochlorite (NaOCl) irrigation is critical to endodontic success, and several new methods have been developed to improve irrigation efficacy (eg, passive ultrasonic irrigation [PUI] and EndoActivator [EA]). Using a novel spectrophotometric method, this study evaluated NaOCl irrigant extrusion during canal irrigation.

Methods: One hundred fourteen single-rooted extracted teeth were decoronated to leave 15 mm of the root length for each tooth.

Palatal anesthesia: comparison of four techniques for decreasing injection discomfort.

Introduction: The aim of this study was to evaluate the patient's perceived pain response to injection and anesthetic deposition for the greater palatine nerve block.

Methods: Heft-Parker Visual Analog Scale (VAS) pain scale measurements were used to compare the following techniques for the injection: (1) control (no concurrent stimulation), (2) pressure, (3) pressure and topical anesthetic (20% benzocaine), and (4) pressure and cold (TFE). Forty-two volunteers, 21 male and 21 female, participated in the study.

An anatomical investigation of the mandibular second molar using micro-computed tomography.

Purpose: An understanding of root anatomy is an important foundation for providing successful endodontic treatment. The aim of this study was to use micro-computed tomography (micro-CT) to investigate the root anatomy of the mandibular second molar.

Methods: Eighteen mandibular second molars were scanned using micro-CT.

Effect of Ibuprofen on masking endodontic diagnosis.

Introduction: An accurate diagnosis is of upmost importance before initiating endodontic treatment; yet, there are occasions when the practitioner cannot reproduce the patient's chief complaint because the patient has become asymptomatic. Ibuprofen taken beforehand may "mask" or eliminate the patient's symptoms. In fact, 64%-83% of patients with dental pain take analgesics before seeing a dentist.

An anatomic investigation of the mandibular first molar using micro-computed tomography.

Introduction: The mandibular first molar is the most frequently endodontically treated tooth and is extremely anatomically challenging. The purpose of this micro-computed tomographic evaluation was to quantitatively investigate the morphology of the mandibular first molar to improve both orthograde and retrograde treatment.

Methods: Twenty-two mandibular first molars were scanned, reconstructed, and subjected to various linear measurements.

The effect of powder:liquid ratio and pre-mixing on sealing properties of Roth 801 sealer.

Objectives: To investigate the sealing ability of Roth 801 sealer mixed using two different powder/liquid ratios and prepared up to seven days prior to canal obturation.

Study Design: Of the 152 maxillary anterior teeth endodontically instrumented for this study, 144 were randomly assigned to the treatment group, and eight were assigned to the control group. Of the 144 teeth in the treatment group, 72 were obturated using gutta-percha and Roth 801 sealer mixed with a 10:1 ratio, while the remaining 72 were obturated with a sealer ratio of 7.

Mandibular first molar with six separate canals.

Introduction: Many anatomical variations can occur within the mandibular first molar. Commonly, 3-4 canals are located, but as many as 6-7 canals have been reported.

Methods: This report describes a case of a mandibular first molar with 6 separate canals (3 mesial and 3 distal) that was instrumented with conventional hand and rotary files and obturated by using a hybrid warm vertical compaction technique.

Challenges in regenerative endodontics: a case series.

Introduction: An immature tooth with pulpal necrosis and apical periodontitis presents a unique challenge to the endodontist. Endodontic treatment options consist of apexification, apical barriers, or more recently, revascularization. The purpose of this case series is to report three cases that used revascularization protocol as described by Banchs and Trope.

Identify and determine the metrics, hierarchy, and predictive value of all the parameters and/or methods used during endodontic diagnosis.

A Consensus Conference on Terminology was convened by the American Association of Endodontists in Chicago on Oct 3, 2008 to review solicited papers on focused questions. This paper addressed the question: Identify and determine the metrics, hierarchy, and predictive value of all the parameters and/or methods used during endodontic diagnosis. The best available clinical evidence was used to determine the sensitivity, specificity, and predictive value of pulpal and periapical testing methods and imaging technologies.

Evaluation of pretreatment analgesia and endodontic treatment for postoperative endodontic pain.

This study compares single-dose ibuprofen pretreatment for postoperative endodontic pain. Thirty-nine emergent patients were randomly assigned to 3 groups: placebo, ibuprofen tablets, or ibuprofen liquigels. Patients recorded their pain levels before and at the end of treatment, then every 6 hours for 24 hours after administration of the medications and standard endodontic treatment.

Effect of irrigants and cementum injury on diffusion of hydroxyl ions through the dentinal tubules.

This study measured hydroxyl ion diffusion through dentinal tubules into a bathing solution. Eighty single-canal, instrumented teeth were divided into 8 groups. Control groups 1 and 3 were irrigated with 10 mL 0.

Shaping abilities of two different engine-driven rotary nickel titanium systems or stainless steel balanced-force technique in mandibular molars.

The purpose of this study was to compare apical transportation, working-length changes, and instrumentation time by using nickel-titanium (Ni-Ti) rotary file systems (crown-down method) or stainless steel hand files (balanced-force technique) in mesiobuccal canals of extracted mandibular molars. The curvature of each canal was determined and teeth placed into three equivalent groups. Group 1 was instrumented with Sequence (Brasseler USA, Savannah, GA) rotary files, group 2 with Liberator (Miltex Inc, York, PA) rotary files, and group 3 with Flex-R (Union Broach, New York, NY) files.

The effect of ultrasonic post instrumentation on root surface temperature.

This study measured root surface temperature changes when ultrasonic vibration, with and without irrigation, was applied to cemented endodontic posts. Twenty-six, extracted, single-rooted premolars were randomly divided into two groups. Root lengths were standardized, canals instrumented, obturated, and posts cemented into prepared spaces.

Cemental tear: a case report of a rare root fracture.

A 79-yr-old female presented to the clinic for endodontic evaluation of an unresolved periodontal defect. The patient's dental history included extraction of tooth #30 with subsequent placement of two dental implants. The patient presented with a localized periodontal defect on the distal of tooth #29.

Leakage and sealer penetration in smear-free dentin after a final rinse with 95% ethanol.

Forty extracted maxillary incisors were decoronated, prepared in a crown-down fashion and randomly divided into two groups of 16 roots each. Remaining roots served as controls. Smear layer was removed with 17% EDTA followed by 5.

In vitro radiographic determination of distances from working length files to root ends comparing Kodak RVG 6000, Schick CDR, and Kodak insight film.

Previous studies suggest that digital and film-based radiography are similar for endodontic measurements. This study compared the accuracy and acceptability of measured distances from the tips of size #10 and #15 files to molar root apices in cadaver jaw sections using the newly developed Kodak RVG 6000, and the Schick CDR digital systems to digitized Kodak film. Standardized images were taken of files placed 0.