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Objective To investigate the effect of endodontic instrumentation on fracture susceptibility of root dentin using experiments and stress analysis. Methods Root canals of lower premolars were enlarged with different tapers. After, teeth were cut into 2-mm sections. A metal rod of the same taper was pushed through the center of the sections using a universal test system to fracture them. The fracture load was determined from the peak load on the load-displacement curve. To determine fracture-causing stress, an axisymmetric FE model was created. An analytical solution was developed to understand the relationship between fracture load, geometrical and material parameters. Results For the same taper, increased root canal diameter did not lead to reduced fracture load. Both analytical and FE solutions showed positive linear relationship between fracture load and enlarged root canal diameter. The hoop stress was maximum at inner surface of enlarged root canal and reduced with increasing radial distance from the center. Bending of sections introduced further nonuniform stresses along the depth. Predictions for the fracture load based on the maximum hoop stress were closest to experimental values; however, account must be taken of the variation in fracture stress of dentin along the root length. Significance Our results rejected the hypothesis that fracture load of root dentin sections reduced with endodontic instrumentation size. However, the stress distributions in whole endodontically treated teeth are more complicated. Thus, caution is necessary when using thin root sections to investigate the effect of endodontic instruments on vertical root fracture.

Introduction The aim of this study was to evaluate the effect of different access opening restorative materials on crown retention. Methods Thirty-eight extracted molars were mounted in resin and prepared for porcelain fused to metal (PFM) crowns. The crowns were fabricated and cemented with zinc phosphate, and the force to displace it was measured with a tensile-testing machine before and after endodontic access preparations. The endodontic access area, crown preparation axial wall, and preparation surface area were measured for comparison. The crowns were then recemented, and access openings were restored with either amalgam or composite before displacement force was remeasured. The restorative material was removed from each access opening; access area was measured and restored again (amalgam with composite or fiber post with composite) for displacement force to be remeasured. Paired t test was used to compare the means of displacement between groups. One-way analysis of variance was used to compare the mean outcome measure within the groups. Results Statistical analyses showed retention after unfilled access was significantly lower than intact crowns. Amalgam, composite, amalgam + composite, and fiber post + composite increased retention beyond the original value. There was no statistical difference among the different restorative protocols. Qualitative results indicate that the restorative material remains in the crown after displacement regardless of the material used to restore the access. Conclusions The results from this study suggest that an endodontic access cavity decreases retention of a PFM crown. However, subsequent restoration with amalgam, composite, amalgam + composite, or post + composite may increase the original retention of the crown.

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 (3.0–3.6 mm), bone thickness over these roots, and the proximity of each root apex to the maxillary sinus will help the surgeon before and during the surgical procedure. Methods Cone-beam computed tomography scans from 155 patients were used to evaluate measurements from 505 teeth and respective areas. Results (1) Buccal bone was thinnest over the buccal root of the 2-rooted first premolar (0.66 mm) and the mesiobuccal (MB) root of the first molar (0.84 mm) and thickest over the MB root of the second molar (1.91 mm). (2) The palatal bone was thinnest over the palatal root of the maxillary first molar (1.24 mm) and thickest over the single-rooted second premolar (3.26 mm). (3) The longest distances to complete resection were found for the 2-rooted first and second premolars (8.81 mm and 9.14 mm, respectively) and the MB root of the second molar (7.40 mm). (4) The MB root of the second molar had the closest proximity to the sinus floor, with an average distance of 0.66 mm. Conclusions An understanding of the maxillary posterior tooth anatomy for apical resection is beneficial to the endodontist.

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. Eighteen mandibular second molars were scanned using micro-CT. Images were reconstructed, and measurements and observations were recorded regarding pulpal floor anatomy, canal configuration, root wall thickness along the root, presence of calcifications in the pulp chamber and in canals, and apical anatomy. The most frequently found mesial root canal configuration was Vertucci Type 7 (1-2-1-2), which was seen in 33.3 % of samples. Distal canals were most frequently Vertucci Type 1 (one canal), with 61.1 % of samples showing this configuration. 11.1 % of samples had two canals, 44.4 % of samples had three canals, 33.3 % of samples had four canals, and 11.1 % of samples had five canals at some point along the length of the roots. Average root wall thickness between the mesiobuccal canal and the furcation was 1.23 mm. Mesiolingual canal root wall thickness was on average 1.29 mm, and the distal root furcation wall thickness averaged 1.41 mm. 77.8 % of samples had calcifications present in both the pulp chamber and within the canals.

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. The purpose of this study was to examine the possible “masking” effect of ibuprofen on endodontic diagnostic tests. Methods Forty-two patients with endodontic pain underwent testing (cold, percussion, palpation, and bite force measurement) and then received either placebo or 800 mg ibuprofen. Both patients and operators were blinded to the medication received. One hour later, diagnostic testing was repeated and compared with pretreatment testing. Results Ibuprofen affected testing values for vital teeth by masking palpation 40%, percussion 25%, and cold 25% on affected teeth with symptomatic irreversible pulpitis and symptomatic apical periodontitis. There was no observed masking effect in the placebo group on palpation, percussion, or cold values. When nonvital teeth were included, the masking effect of ibuprofen was decreased. However, little masking occurred with the bite force measurement differences. Conclusions Analgesics taken before the dental appointment can affect endodontic diagnostic testing results. Bite force measurements can assist in identifying the offending tooth in cases in which analgesics “mask” the endodontic diagnosis

Introduction Most radiolucent jaw lesions are benign and resolve with proper diagnosis and treatment. However, a small percentage of radiolucent jaw lesions are malignant and more difficult to manage. Methods A biopsy of the radiolucent jaw lesion associated with swelling after nonsurgical root canal therapy was submitted. Results The lesion had the combined diagnosis of diffuse large B-cell lymphoma with cystic involvement. The patient has since undergone radiation and chemotherapy treatments. Recall appointments indicate healing of the lesion, and no other areas of lymphoma have been found. Conclusions The existence of a nonhealing radiolucent jaw lesion emphasizes the importance of an early, definitive diagnosis with biopsy.

Introduction Dental pain originating from the maxillary sinuses can pose a diagnostic problem. Periapical lesion development eliciting inflammatory changes in the mucosal lining can cause the development of a sinusitis. The purpose of this study was to describe the radiographic characteristics of odontogenic maxillary sinusitis as seen on cone-beam computed tomography (CBCT) scans and to determine whether any tooth or any tooth root was more frequently associated with this disease. Methods Eighty-two CBCT scans previously identified as showing maxillary sinus pathosis were examined for sinusitis of odontogenic origin in both maxillary sinuses. Results One hundred thirty-five maxillary sinusitis instances with possible odontogenic origin were detected. Of these, 37 sinusitis occurrences were from nonodontogenic causes, whereas 98 instances were tooth associated with some change in the integrity of the maxillary sinus floor. The average amount of mucosal thickening among the sinusitis cases was 7.4 mm. Maxillary first and second molars were 11 times more likely to be involved than premolars, whereas either molar was equally likely to be involved. The root most frequently associated with odontogenic sinusitis is the palatal root of the first molar followed by the mesiobuccal root of the second molar. Conclusions Changes in the maxillary sinuses appear associated with periapical pathology in greater than 50% of the cases. Maxillary first or second molar teeth are most often involved, and individual or multiple roots may be implicated in the sinusitis. The use of CBCT scans can provide the identification of changes in the maxillary sinus and potential causes of the sinusitis.

Introduction Orofacial pain is a common encounter in dentistry (affecting 12% of the population) and is a primary reason for patients seeking emergency care. Dentists often prescribe oral analgesics, which have disadvantages of decreased absorption rates and delayed onset. Intranasal (IN) delivery takes advantage of a large surface area of mucosal tissue for rapid absorption. The purpose of this study was to evaluate the efficacy of IN ketorolac for endodontic pain using a randomized, double-blind, placebo-controlled parallel design study. Methods Twenty-two patients presenting with moderate to severe endodontic pain were selected to receive IN treatment with placebo (n = 11) or ketorolac (n = 11) 30 minutes before endodontic treatment was started and immediately after the completion of endodontic treatment. Baseline pain levels were recorded before IN treatment. Pain levels were also recorded at 15 and 30 minutes after the initial IN dosing (before endodontic treatment); 30 minutes after completion of endodontic treatment; and 4, 8, and 12 hours after the initial IN spray. Primary analysis was a repeated-measures analysis of variance. Results IN ketorolac alone or with endodontic treatment showed significantly better pain relief compared with IN placebo spray alone or with endodontic treatment at 30 minutes after the first or second intranasal dose and at 4 hours after the first intranasal dose (P = .03). Conclusions These results suggest that IN ketorolac may provide a novel and efficacious method for pain relief in endodontic pain patients.

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. Each case presented its own special circumstances and challenges. The lessons learned from each case provided guidance for more predictable outcomes on subsequent cases. Methods Six immature teeth with apical periodontitis (in three patients) were treated via the revascularization protocol using irrigants, a triple antibiotic paste, and a coronal seal of mineral trioxide aggregate and composite. Results For follow-up, all six teeth showed resolution of periapical radiolucencies, whereas three of six teeth showed continued root development. Two teeth displayed a positive response to vitality testing. Conclusions Results from this case series show that revascularization is a technically challenging but effective treatment modality for the immature tooth with apical periodontitis. Based on this case series, the following recommendations are made to help with the revascularization technique: (1) clinicians should consider the use of an anesthetic without a vasoconstrictor when trying to induce bleeding, (2) a collagen matrix is useful for the controlled placement of MTA to a desired and optimal level, (3) patients/parents should be informed about the potential for staining, especially in anterior teeth when the paste contains minocycline, and (4) patient/parent compliance with the necessary multiple appointment treatment plan may be significant for case selection.

Surgical endodontics involving root resection/apical fill are often performed when retreatment by orthograde endodontic procedures are not possible. Because of the potential presence of accessory canals within the root, a preferred minimal root resection level should be investigated for the removal of the majority of these canals. One hundred fifty-three extracted, uninstrumented, mesiobuccal roots from first and second maxillary molars were examined for the presence of accessory canals, canal isthmus, and canal wall thickness. Three hundred ninety accessory canals were identified, with 80% of these canals located within 3.64 mm of the apex of the tooth. Canal isthmus was often not evident until 3.12 mm of the root was resected, with canal wall thickness only approximating 1 mm thick. The observations here suggest a minimal resection level to 3.6 mm for accessory canal incidence, canal isthmus detection, and canal wall thickness and provide a better understanding of maxillary mesiobuccal (MB) root anatomy for retrograde root resection/apical filling.

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. Pre- and postoperative radiographs were superimposed to measure loss of working length and apical transportation as shown by changes in radius of curvature and the long-axis canal angle. Sequence rotary files, Liberator rotary files, and Flex-R hand files had similar effects on apical canal transportation and changes in working length, with no significant differences detected among the 3 groups. Hand instrumentation times were longer than with either Ni-Ti rotary group, whereas the rotary NiTi groups had a higher incidence of fracture.

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).Forty-six intact teeth (23 tooth pairs) in 22 patients were evaluated in vivo. For the tooth pairs, one tooth had to have been previously endodontically treated and restored with a class II amalgam restoration. The restoration was required to have proximal contact with a class II amalgam of another vital posterior tooth. EPT was performed on pulpless and vital teeth for experimental groups (enamel, restoration, contacting, or isolated).The highest rate of false positive responses (82%) was found in the pulpless restored contacting group, suggesting that EPT impulses are able to travel through proximal metallic contacts and stimulate teeth distant from the EPT probe. All vital tooth groups had a high rate of positive responses with no significant diferences.If a tested tooth contains an interproximal restoration contacting adjacent restorations or the gingival, the teeth must be isolated (rubber dam) and the EPT probe should be placed in a region suspected to have uninterrupted tubule paths to the pulp.

To determine if there is increased bacterial communication through the furcation region in molar teeth after simulated periodontal therapy.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. In Phase I, the teeth were sterilized and then suspended in Rogosa SL broth. A broth containing Lactobacillus casei was placed in the pulp chamber. The Rogosa SL broth in the bottom chamber was monitored daily for 30 days for turbidity, and once turbidly was noted, the broth was plated to confirm the presence of L. casei. In Phase II, the furcation regions were scaled and cementum removed, the teeth were sterilized, and the microbial leakage was repeated.The Phase I and Phase II median times to turbidity were 9.5 days and 4 days, respectively, and the difference was statistically significant (p = 0.0035). Phase I turbidity rate was 86.5%, and Phase II was 92.3%, which was not statistically significant (p = 0.25).The root canal system communicated with the furcation region an average of 86.5% and 92.5% after scaling and root planing during the 30 days of the experiment. The time of leakage between the two groups decreased from 9.5 to 4 days (p = 0.0035).Periodontal instrumentation of the furcation region in molar teeth can increase the risk of bacterial contamination by 39% while shortening the time for bacterial penetration in teeth with exposed dentin or furcation canals. accessory canals, scaling, and root planing.

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. Results Respective locations of MC to teeth (buccal, inferior, or lingual) were as follows: second molar (57% buccal, 40% inferior, and 3% lingual), first molar (18% buccal, 55% inferior, and 27% lingual), and second premolar (33% buccal, 55% inferior, and 11% lingual). Buccal bone thickness over the MC was thickest at mesial root of second molars and thinnest over the second premolar (5.4 versus 2.6 mm). The lingual bone next to the MC was thickest over the second premolar and thinnest at distal root of first molars (3.8 versus 1.7 mm). The average diameter of the MC along the length of the canal from second molar to second premolar was 3.03 mm on left and 2.91 mm on right. The anterior loop was present in 10.4% of patients, with the average depth below bone of 13.43 mm. The anterior loop was more often seen on the left side than right and occurred bilaterally 50% of the time. Conclusions Mandibular bone thickness, nerve location, and dimension data all contribute to a useful knowledge base for practitioners. The application of CBCT imaging techniques aids in the surgical treatment, while offering advantages over conventional periapical and panoramic films.

Initial root canal treatment and the replacement of a single tooth with an implant are both viable treatment options, but various success rates have been reported for each treatment modality. This retrospective study compared 196 implant restorations and 196 matched initial nonsurgical root canal treatment (NSRCT) teeth in patients for four possible outcomes: success, survival, survival with subsequent treatment intervention and failure. Cross classifications/tabulations were analyzed using Pearson's chi2 test for association of the two classifications (endodontic vs implant and outcome). Polytomous regression with likelihood ratio tests were used in testing association with tooth location and outcome. Outcomes were as follows for implants and NSRCT respectively: success 73.5% and 82.1%; survival with no intervention 2.6% and 8.2%; survival with intervention 17.9% and 3.6%; and failure 6.1% and 6.1%. Location of the restoration in the mouth did not affect outcome. This study suggests that restored endodontically treated teeth and single tooth implant restorations have similar failure rates, although the implant group showed a longer average and median time to function and a higher incidence of postoperative complications requiring subsequent treatment intervention.

Objective To explore the potential of detecting the level of proinflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha), interleukin-1-alpha (IL-1-alpha), IL-6, and IL-8 in whole unstimulated saliva (WUS) in monitoring the therapeutic effects of topical dexamethasone on these salivary cytokines in subjects with erosive oral lichen planus (OLP). Study design Thirteen definitively diagnosed OLP subjects were enrolled in the study as were 13 age- and sex-matched controls. The OLP subjects were treated with 0.1% dexamethasone oral rinse for 6 weeks. Prior to treatment and at the end of clinical trial, the visual analog scale (VAS) for symptoms was recorded, WUS was collected and these proinflammatory cytokines were analyzed by ELISA. Results Following the dexamethasone treatment, the levels of TNF-alpha, IL-1-alpha, IL-6, and IL-8 were decreased significantly, and IL-1-alpha and IL-8 were detected at a level without a statistically significant difference from controls. VAS value was decreased significantly and was found to significantly correlate with the decrease in IL-1-alpha and IL-8 levels. Conclusions These preliminary results indicate that salivary analysis of NF-kappaB-dependent cytokines may be applied to monitoring the therapeutic response of OLP.

Objective Calcium hydroxide (Ca(OH)2) has been used in endodontics as an intracanal medicament due to its antimicrobial effects and its ability to inactivate bacterial endotoxin. The inability to totally remove this intracanal medicament from the root canal system, however, may interfere with the setting of eugenol-based sealers or inhibit bonding of resin to dentin, thus presenting clinical challenges with endodontic treatment. This study used a chemical titration method to measure residual Ca(OH)2 left after different endodontic irrigation methods. Material and Methods Eighty-six human canine roots were prepared for obturation. Thirty teeth were filled with known but different amounts of Ca(OH)2 for 7 days, which were dissolved out and titrated to quantitate the residual Ca(OH)2 recovered from each root to produce a standard curve. Forty-eight of the remaining teeth were filled with equal amounts of Ca(OH)2 followed by gross Ca(OH)2 removal using hand files and randomized treatment of either: 1) Syringe irrigation; 2) Syringe irrigation with use of an apical file; 3) Syringe irrigation with added 30 s of passive ultrasonic irrigation (PUI), or 4) Syringe irrigation with apical file and PUI (n=12/group). Residual Ca(OH)2 was dissolved with glycerin and titrated to measure residual Ca(OH)2 left in the root. Results No method completely removed all residual Ca(OH)2. The addition of 30 s PUI with or without apical file use removed Ca(OH)2 significantly better than irrigation alone. Conclusions This technique allowed quantification of residual Ca(OH)2. The use of PUI (with or without apical file) resulted in significantly lower Ca(OH)2 residue compared to irrigation alone.

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.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. A bilateral model was used on each patient to give an injection on each side of the palate with two different techniques followed by the next appointment (or = two weeks later), when the two other injection techniques were used. Following injection given in the supine position, the patients were returned to an upright position and asked to rate their pain on a VAS.Pain upon needle insertion appears less than that of anesthetic deposition. There was no statistically significant difference in perceived pain response among the four techniques, the visit, the order, the side, or patient gender at either time point. Following the application of Endo Ice, 81% of participants reported a sore on their palate occurring two to 48 hours after cold application and persisting for one to 10 days. The pain score for this injection had a mean value of 30% (51.4/170).This prospective, single-blind study evaluating three injection techniques to reduce posterior palatal injection pain to a control injection method showed no significant reduction in pain with any of the three techniques. Furthermore, 1,1,1,2-tetrafluoroethane placed with pressure for 10 seconds appeared injurious to the oral mucosa.

Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter that is elevated in inflamed human dental pulp. Because GABA agonists are antihyperalgesic in other tissue, it is possible that GABA agonists have similar effects in dental pulp assuming that this tissue contains GABA receptors. We tested the hypothesis that dental pulp contains functional GABA(B) receptors using a GTPgamma35S binding assay. This is a functional assay because GTPgamma35S will be bound to cell membranes only when activation of metabotropic receptors has lead to binding and activation of their associated G(alpha)-proteins via release of GDP and binding of the GTPgamma35S. Baclofen, a GABA(B) agonist, evoked GTPgamma35S binding in both human and bovine dental pulp. This was mediated by the GABA(B) receptor because it was blocked by the selective antagonist phaclofen in both tissues. The presence of GABA and its receptor, GABA(B), suggests that this system may be relevant in the production or management of endodontic pain.

The adrenal cortex is innervated by afferent fibers that have been implicated in affecting cortical steroidogenesis. Modulation of neurotransmitter release from afferents may represent a regulatory system for the control of adrenal cortical function. The present studies validate an in vitro superfusion technique for adrenal capsules employing the drug capsaicin, which activates a subset of afferent fibers and induces the release of calcitonin gene-related peptide (CGRP). Capsaicin-evoked CGRP release from adrenal afferents was blocked by capsazepine, a competitive antagonist for the capsaicin receptor, or by removal of extracellular calcium. Exogenous ACTH prevented capsaicin-evoked CGRP release, elevated basal aldosterone release, and prevented capsaicin-induced reduction in aldosterone release. Immunolabeling for the recently cloned capsaicin vanilloid receptor 1 demonstrated its presence in adrenal nerves. These results show that in vitro superfusion of adrenal capsules can be used to characterize factors that modulate neurotransmitter release from adrenal afferents. Furthermore, the results suggest that activation of adrenal afferents in vivo may attenuate aldosterone steroidogenesis and that high levels of ACTH may prevent this phenomenon.

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. Cleaning and shaping of the teeth were completed using standardized hand and rotary instrumentation to an apical file size #40/0.04 taper. Roots were sealed (not apex), and 54 straight roots (n = 18/group) and 60 curved roots (>20° curvature, n = 20/group) were included. Teeth were irrigated with 5.25% NaOCl by 1 of 3 methods: passive irrigation with needle, PUI, or EA irrigation. Extrusion of NaOCl was evaluated using a pH indicator and a spectrophotometer. Standard curves were prepared with known amounts of irrigant to quantify amounts in unknown samples. Results Irrigant extrusion was minimal with all methods, with most teeth showing no NaOCl extrusion in straight or curved roots. Minor NaOCl extrusion (1–3 μL) in straight roots or curved roots occurred in 10%–11% of teeth in all 3 irrigant methods. Two teeth in both the syringe irrigation and the EA group extruded 3–10 μL of NaOCl. Conclusions The spectrophotometric method used in this study proved to be very sensitive while providing quantification of the irrigant levels extruded. Using the PUI or EA tip to within 1 mm of the working length appears to be fairly safe, but apical anatomy can vary in teeth to allow extrusion of irrigant.

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.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 7.5:1. Within both treatment groups, the teeth were further subdivided into six groups of 12 teeth based upon the amount of time between sealer mixing and canal obturation, which varied from 0 days to seven days. Teeth were analyzed with fluid filtration either immediately after obturation or 14 weeks after obturation. The data were analyzed using a three-way analysis of variance.For teeth tested at the time of obturation, leakage decreased for older sealer, p0.0001. After the 14-week storage period, there was no significant difference in leakage. No significant differences were noted between either powder/liquid ratios.Pre-mixed Roth 801 sealer maintained an apical seal when prepared up to seven days prior to canal obturation. Varying the powder/liquid ratio of Roth 801 sealer did not significantly affect the apical seal.

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 average, standard deviation, and standard error of the mean of each linear measurement were calculated, and the mode for each nominal data category was determined. Results/Conclusions The furcal aspect of the entire mesial root should be considered a “danger zone.” Mesial canals were found to be much more variable than distal canals in morphology, whereas the relative position of the orifices of the mesial canals was relatively consistent at 1.5 mm from the pulpal floor. Root-end resection of 3 mm would remove the majority of lateral canals and apical ramifications.

Odontogenic pain often involves inflammation of dental pulp tissue. Dental pulp is highly innervated with a subpopulation of sensory neurons containing neuropeptides. Substance P, released from afferent fibers (e.g. nociceptors) is associated with the development of neurogenic inflammation. In this study, we tested the hypothesis that irreversible pulpitis is associated with increased activity of peptidergic neurons, as measured by increased pulpal levels of immunoreactive substance P (iSP). We determined in vivo pulpal levels of immunoreactive substance P in human teeth with a diagnosis of normal pulp or irreversible pulpitis using CMA/20 microdialysis probes inserted into vital pulps of 24 teeth from 21 patients. Probes were perfused with a modified Locke-Ringer's buffer and immunoreactive substance P levels in the dialysate were measured using a radioimmunoassay. Mean extracellular levels of immunoreactive substance P were significantly higher (8-fold) in teeth diagnosed with irreversible pulpitis than immunoreactive substance P levels in dental pulp diagnosed as normal (147.7 +/- 34.0 pM versus 18.2 +/- 6.2 pM). These observations suggest that biochemical measures of inflammatory mediators exhibit significant change during irreversible pulpitis and may contribute to clinical signs and symptoms.

Introduction Patients with irreversible pulpitis occasionally present with a chief complaint of sensitivity to heat. To appropriately diagnose the offending tooth, a variety of techniques have been developed to reproduce this chief complaint. Such techniques cause temperature increases that are potentially damaging to the pulp. Newer electronic instruments control the temperature of a heat-testing tip that is placed directly against a tooth. The aim of this study was to determine which method produced the most consistent and safe temperature increase within the pulp. This consistency facilitates the clinician's ability to differentiate between a normal pulp and irreversible pulpitis. Methods Four operators applied the following methods to each of 4 extracted maxillary premolars (for a total of 16 trials per method): heated gutta-percha, heated ball burnisher, hot water, and a System B unit or Elements unit with a heat-testing tip. Each test was performed for 60 seconds, and the temperatures were recorded via a thermocouple in the pulp chamber. Analysis of the data was performed by using the intraclass correlation coefficient. Results The least consistent warming was found with hot water. The heat-testing tip also demonstrated greater consistency between operators compared with the other methods. Hot water and the heated ball burnisher caused temperature increases high enough to damage pulp tissue. Conclusions The Elements unit with a heat-testing tip provides the most consistent warming of the dental pulp.

Practitioners should be aware of the occurrence rate and usual location of radiolucent jaw lesions. The aims of this study were to examine the frequency and location of radiolucent jaw lesions, including apical granulomas, apical cysts, keratocystic odontogenic tumors (KOTs), central giant cell lesions (CGCLs), ameloblastomas, and metastatic lesions, that were submitted for biopsy along with associated demographics.Biopsy diagnoses from 9,723 lesions (submitted between 1992 and 2006) were included in this study. Data on lesion location as well as patient demographics were evaluated.Thirty types of radiolucent jaw lesions were classified. Nonhealing apical granulomas (40.4%) and cysts (33.1%) occurred at similar rates and together totaled 73% of all biopsied lesions. The majority of reported granulomas and cysts occurred in the anterior maxilla (36% in each category). The frequency of KOTs (8.8%), CGCLs (1.3%), ameloblastomas (1.2%), and metastatic lesions (1%) are to be noted along with their location, which was predominately in the posterior mandible. The occurrence of apical cysts, ameloblastomas, KOTs, and metastatic lesions were seen slightly more in men, at 56%, 54%, 55%, and 68%, respectively. The occurrence of CGCLs was seen slightly more in women at 56%, whereas apical granulomas were equally present in men and women.Most nonhealing lesions submitted for biopsy were classified as granulomas or cysts (73%) often from the anterior maxillary jaw. Nonhealing radiolucent jaw lesions other than granulomas or cysts were reported over 20% of the time and may have more severe pathological implications, suggesting the value of differential diagnoses.

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. Results Recall examination as far as 3 years post-treatment found no sensitivity to percussion or palpation and recall radiographs after treatment show resolution of the previous apical periodontitis. Conclusions The existence of such teeth as these underlies the importance of looking for additional canals.

Introduction Studies to examine sex differences in response to pain have suggested that females exhibit lower threshold responses to painful stimuli and that threshold response varies greatly at different stages of the menstrual cycle. Additional studies suggest that sex differences may be caused by societal sex roles or differences in anxiety responses by men and women. Objective The purpose of this study was to evaluate biologically evident sex differences in male and female rats chronically treated with a systemic algogen, the nerve growth factor (NGF), by measuring neuropeptides (calcitonin gene–related peptide) content and release from isolated dental pulp. Methods Rats were injected subcutaneously every other day with either murine NGF (1 mg/kg) or vehicle for 7 or 13 days. Isolated incisor pulp tissue was evaluated from these male and female rats (n = 96). Capsaicin-evoked neurosecretion of CGRP and tissue content were measured using a previously validated radioimmunoassay. Results Dental pulp from female rats at 7 days showed significantly increased capsaicin-evoked immunoreactive CGRP release (>50% increase) compared with tissue from male rats. After 13 days, this release was significantly increased only in NGF-treated female rats (3-fold increase) when compared with control females or both male groups. The CGRP content in tissue from both female groups was also significantly increased after 7 days of treatment (>3 fold), but after 13 days this content was only significantly increased in tissue from NGF-treated female rats ( P = .0001). Conclusions These data suggest that sex differences affect the role of NGF in the modulation of inflammation through the regulation of peripheral neuropeptide release and content.

Knowledge of the inferior alveolar nerve (IAN) position is important in avoiding nerve damage during invasive dental procedures. Because the exact position of the nerve bundle can vary in patients, this study evaluated the distance from the apices of mandibular premolar and molar teeth to the superior border of the mandibular canal.Cone-beam computed tomography (CBCT) scans from 139 patients were analyzed to evaluate the proximity of the mandibular canal to the root apices of 743 mandibular second premolar and first and second molar teeth. Subjects were subgrouped by age and sex. A random intercept model was used to account for multiple measurements within a patient.In all groups, root apices of the mandibular second molars were closer to the mandibular canal than other teeth. The mesial root of the second molar was closer to the nerve in female patients compared with male patients. Root apices in younger patients (18 years) were generally closer to the mandibular canal than in older patients.The CBCT scan is an accurate, noninvasive method to evaluate the position of the mandibular canal. The variable position of this structure between patients suggests the need for CBCT to determine the proximity of the nerve bundle before attempting invasive treatment in this area. Dental practitioners should consider potential differences of mandibular canal position as a result of age and gender when performing these procedures in this area.

Introduction To increase our understanding of the root canal system, we examined the mesiobuccal (MB) roots of maxillary first and second molars, which are considered to be one of the most complex root canal systems. Methods Uninstrumented MB roots from 153 teeth were imbedded, sectioned, and observed at 8× using a stereomicroscope for main canal numbers, isthmus presence, and dimensional size of canals and dentin walls. Results The number of canals observed in maxillary first and second molars was 20% and 38.1% for one canal, 79.8% and 60.3% for two canals, and 1.1% and 1.6% for three canals, respectively. The buccal canal was larger than lingual or middle canals at all levels of the root. The average distance between the two main canals was 1.2 ± 0.6 mm in first molars and 1.78 ± 0.6 mm in second molars. Isthmus tissue increased greatly at 3.6 mm from the apex, suggesting optimal root resection at this level. Little differences in thickness between mesial and distal canal walls were seen until reaching the coronal sections of the root where the average canal wall thickness was found to be thinner (33%) on the distal, suggesting a “danger zone” for maxillary molars at a level where the root joins the crown of the tooth. Conclusions The observations made here provide a more precise understanding of the maxillary MB root system. Orthograde and retrograde root canal therapy might be improved with a comprehensive understanding of pulpal morphology throughout the entire MB root.

Introduction Endodontic pain patients sometimes have difficulty in accurately identifying the painful tooth. We determined the frequency in which patients presenting with endodontic pain can correctly localize the painful tooth and the effect of periradicular symptoms. Methods The frequency of localization of the painful tooth in 79 endodontic emergency patients was assessed by using patient and dentist assessment of presenting pain along with the verbal numeric rating scale (VNRS). Results The results show that patients presenting with odontogenic pain can localize the painful tooth 73.3% of the time. Patients experiencing periradicular pain can localize the painful tooth (89%) significantly more often than patients with pain without periradicular symptoms (30%, p Conclusions The presence of periradicular pain increases the accuracy of pain localization. The VNRS is highly correlated with other pain scales and is an acceptable inital pain-assessment tool for endodontic emergency patients.

Chlorhexidine (CHX) is effective in treating oral bacterial infections. The solubility was shown to be highly dependent on the salt present in solution. Gluconate enhances the amount of CHX diacetate in solution possibly through mixed micelles formation, because the solubility product is such that the concentration of CHX will exceed the critical micelle concentration. However, only low concentrations of CHX dichloride can be obtained, which is not appreciably solubilized by gluconate ions. The low concentration of CHX that can be achieved in physiological concentrations of chloride in the oral cavity may be problematic for dental, slow release formulations.

Purpose Chlorhexidine (CHX), a chemical antiseptic, is known to bind to dentin and has been shown to be effective in treating bacterial infections caused by microbes. The solubility and aggregation properties of CHX salts were determined to guide the development of a sustained release formulation for long-term disinfection. Methods The amount of CHX in solution was determined as a function of counterion concentration (chloride, acetate (Ac) or gluconate (G)) by UV spectrophotometry at 255 nm. The weight average molecular weight was determined from the angular dependence of the scattered light. Proton NMR spectroscopy was used to investigate the dependence of the peak intensity and chemical shift on solution concentration and diffusion measurements were performed by Fourier-transform pulsed-field gradient spin-echo (PFG-SE) 1 H NMR. Results The observed CHX concentration was highly dependent on the type and concentration of salt present in solution with the greatest CHX concentration achieved with gluconate, moderate to low with diacetate, and very low with dichloride solutions. Addition of sodium gluconate enhanced the amount of CHX-Ac 2 in solution; however, only low concentrations of chlorhexidine can be achieved in the presence of chloride ions. For solutions of CHX-G 2 , the aggregate number appeared to range from a dimer at 40 mM to perhaps a pentamer at 150 mM. In contrast, no aggregation of CHX-Cl 2 or CHX-Ac 2 was detected, which was corroborated by diffusion NMR results. The change in chemical shift of protons is consistent with association of the phenyl group of one CHX with the hexamethylene chain of a second CHX. Based on the analysis of NMR peak intensities of CHX, gluconate, and acetate in saturated solutions, it appears that solubilization of the diacetate species occurs within digluconate aggregates, since the solubility product of chlorhexidine diacetate is such that the concentration of CHX will exceed the critical micelle concentration (CMC). However, no solubilization of CHX-Cl 2 occurs because the solubility product falls below the CMC. Conclusions The low concentration of CHX that can be achieved in physiological concentrations of chloride in the oral cavity may be problematic for dental and slow release formulations. Achieving a high concentration of CHX appears to require that the monomer be present at a concentration greater than that required to produce self-association.

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. Pain evaluations by using 3 pain scales (visual analog scale [VAS], category, and Heft-Parker) were highly correlated, suggesting the rationale for only using one pain scale in pain studies. No significant differences in postoperative pain levels were found between either single-dose ibuprofen formulation or the placebo control group (P = .84). Patients treated with calcium hydroxide versus obturation did not differ in postoperative pain levels (P = .44). This study suggests that single-dose pretreatment analgesia alone in endodontic pain patients will not significantly reduce postoperative pain below the reduction in pain from endodontic treatment.

The purpose of this prospective clinical trial was to investigate the analgesic efficacy of three oral medication groups on postoperative endodontic pain in male and female dental patients, with an emphasis on analgesic differences between the sexes. Forty-three patients were administered ibuprofen 600 mg, placebo, or pentazocine 50 mg/0.5 mg naloxone in a randomized, double-blinded manner. Beginning immediately after endodontic treatment, patients took the assigned medication every 6 hours for 24 hours and recorded their degree of discomfort on a 100-mm visual analog scale. Statistical analysis of the data showed that ibuprofen 600 mg provided statistically significantly greater analgesia than placebo at 6 and 12 hours (P = 0.0014 and 0.0024), and pentazocine/naloxone provided statistically significantly greater analgesia than placebo at 12 hours (P = 0.0084). Sex-dependent differences were noted within the pentazocine/naloxone group, which showed significantly greater analgesia in females compared with males (P = 0.007).

To evaluate the speed (efficiency) and effectiveness of 3 different fiber post removal systems.Fiber posts (D.T. Light-Post no. 1 [Bisco Dental] and ParaPost FiberLux no. 5 [Coltène/Whaledent]) were cemented into 60 single-rooted teeth after endodontic therapy and post space preparation were completed. Three methods of fiber post removal were evaluated-D.T. Light-Post removal kit, the Kodex twist/Tenax ParaPost fiber post removal drill kit, and a combination of diamond bur/Peeso reamer.The efficiency to remove either fiber post was not significantly different, nor was efficiency of any of the 3 post removal systems significantly different. For effectiveness, no difference was observed between post types, but effectiveness was higher with the diamond bur/Peeso reamer compared with the Kodex twist/Tenax ParaPost drills, which in turn was more effective than the D.T. Light-Post removal kit.Fiber posts are efficiently removed by all 3 methods, but effectiveness of removal is higher using the diamond bur/Peeso reamer.

Nerve growth factor (NGF) plays an important role in inflammation and pain and has been suggested to regulate the responsiveness and sensitivity of nociceptive fibers. However, no study has evaluated whether chronic NGF alters the exocytotic capacity of peripheral terminals of peptidergic fibers. To test this hypothesis, rats were injected subcutaneously every other day with either murine recombinant NGF (mNGF; 1.0 mg/kg) or vehicle for 7 days; or mNGF (0.1 mg/kg), mNGF (1 mg/kg) or vehicle every other day for 13 days. Treatment of rats with NGF over a 13-day period produced a significant increase in capsaicin-evoked iCGRP release from isolated biopsies of hindpaw skin, as assessed by in vitro superfusion and RIA. This effect was dose-dependent and exhibited a temporal requirement, because the enhancement was only observed after 13 days of treatment and was not evident after 7 days of treatment. This NGF enhancement of capsaicin-evoked iCGRP release was not due solely to increases in peripheral iCGRP content since only the 1 mg/kg dose of NGF elevated cutaneous pools of iCGRP, whereas both doses significantly increased capsaicin-evoked peptide release. Moreover, NGF also enhanced capsaicin-evoked thermal hyperalgesia under similar dose- and time-related conditions. Collectively, the chronic administration of NGF not only increases capsaicin-evoked hyperalgesia, but also significantly primes peripheral fibers to enhanced peptidergic exocytosis following activation of the capsaicin receptor. Collectively, these data are consistent with the hypothesis that persistently elevated NGF levels may contribute to enhanced neurogenic regulation of inflammatory and wound healing processes in injured tissue.

To explore the feasibility of detection of the level of NF-κB-dependent cytokines in oral fluids from patient with oral lichen planus (OLP) for clinical application, 13 OLP subjects were enrolled in the study as were 13 age–sex-matched controls. In each subject, the whole unstimulated saliva (WUS), mixture of saliva and isotonic saline oral rinse (Saliva-NaCl), and lesion tissue transudates (TT) were collected by standard techniques. The level of cytokines, TNF-alpha, IL-1-alpha, IL-6, and IL-8 in three types of oral fluids was determined by ELISA. In the three types of oral fluids, a significantly higher level of these cytokines was detected in OLP patients than in normal controls. These results indicate that NF-κB-dependent inflammatory cytokines may be detected at increased levels in certain oral fluids which may have diagnostic and prognostic potential for monitoring disease activity and making therapeutic decisions in patients with OLP.

To evaluate the effect of sealer, dentin bonding agent, and root region on the push-out bond strengths of three tooth colored posts.24 extracted human single rooted maxillary central incisors and canines were endodontically-treated using gutta percha and Roth's 801 or AH26 sealer. Posts (Cosmopost, Fibrekor, or Parapost Fiber White) were placed using one of two adhesive systems (Parapost Cement Conditioner with Parapost Cement, or One-Step with Hi-X Post self-cure resin cement). The push-out test was performed on different sections of the root to measure bond strengths.Cosmopost showed significantly lower mean bond strengths than either Fibrekor or Parapost. Bond strengths of the posts in the crown section were significantly higher than those in any of the three root areas measured. Neither the eugenol-containing sealer nor the bonding agent type had any effect on bond strength. Post type and root region significantly affected bond strength while sealer type or bonding agent had no effect on bond strength.

The effect of systemic nerve growth factor (NGF) on neuropeptide content and capsaicin-evoked release of neuropeptide from in vitro spinal cord dorsal horn slices was examined. Rats were injected subcutaneously every other day with murine NGF (mNGF) 1 mg/kg or saline for 7 days, or mNGF 0.1/kg, mNGF 1 mg/kg or saline for 13 days. Lumbar dorsal horn slices of the rat spinal cord from all groups showed a significant increase in immunoreactive calcitonin gene-related peptide (CGRP) release upon exposure to capsaicin. This release was enhanced in rats pretreated with mNGF 1 mg/kg for 7 days, but not after 13 days. No enhancement was seen after 7 or 13 days in any treatment group for immunoreactive substance P release. Upon examination of neuropeptide content in dorsal horn, no significant differences were noted between treatment groups. The increased iCGRP release from dorsal horn slices suggests a preferential release of CGRP and provides further evidence that NGF indirectly plays a role in the modulation of inflammation through the regulation of neuropeptide release.

Alpha adrenergic agonists (e.g. vasoconstrictors) represent one of the most commonly used drug classes in dentistry. Although adrenergic agonists have potent vascular effects, recent studies suggest that capsaicin-sensitive nociceptors may express adrenoceptors, suggesting that these drugs may directly modulate the function of an important class of pain-signaling neurons in peripheral tissues. In this study, we tested the hypothesis that adrenergic agonists inhibit activation of peripheral terminals of capsaicin-sensitive fibers innervating dental pulp. Pretreatment with epinephrine or clonidine significantly inhibited capsaicin-evoked release of immunoreactive calcitonin gene-related peptide from superfused bovine dental pulp. These studies suggest that adrenergic agonists may reduce postoperative pain in part via a direct inhibition of capsaicin-sensitive nociceptors. This finding may lead to the development of selective, peripherally acting, adrenergic analgesics. Moreover, because neuropeptide release alters blood flow, it is possible that the vascular effects of these drugs are caused by both vasoconstriction and inhibition of peripheral neuropeptide release.

Neurotransmission from sympathetic and peptidergic afferent fibers participates in the regulation of pulpal blood flow (PBF) via opposing effects. In this study, we directly tested the hypothesis that activation of pulpal sympathetic terminals inhibits exocytosis of immunoreactive calcitonin gene-related peptide (iCGRP) from peptidergic afferents innervating bovine dental pulp. The results demonstrate that norepinephrine inhibits capsaicin-evoked iCGRP release. The application of α-adrenergic antagonists (phentolamine or phenoxybenzamine) increased spontaneous release of iCGRP. Moreover, administration of agents that evoke the release of sympathetic neurotransmitters (guanethidine or reserpine) inhibited capsaicin-evoked iCGRP release. Collectively, these results indicate that sympathetic neurotransmission inhibits exocytosis from pulpal peptidergic afferent fibers. Analysis of these data supports the hypothesis that peripheral sympathetic vasomotor control may operate by a direct mechanism (vasoconstriction) as well as by an indirect mechanism ( e.g., inhibition of exocytosis from afferent fibers). Since capsaicin-sensitive neurons are nociceptors, it is possible that certain sympathetic neurotransmission may modulate pain.

Previous studies have suggested that neurotransmitter substances from the sympatho-adrenomedullary system regulate pulpal blood flow (PBF), in part, by the inhibition of vasoactive neuropeptide release from pulpal sensory neurons. However, no study has evaluated the role of β-adrenoceptors. We evaluated the hypothesis that activation of β-adrenoceptors inhibits immunoreactive calcitonin gene-related peptide (iCGRP) release from capsaicin-sensitive nociceptive neurons via in vitro superfusion of bovine dental pulp. Either norepinephrine or epinephrine inhibited capsaicin-evoked iCGRP. The norepinephrine effect was blocked by the selective β2-adrenoceptor antagonist, ICI 118,551, but not by pre-treatment with the selective β1-adrenoceptor antagonist, atenolol. In addition, application of albuterol, a selective β2-adrenoceptor agonist, significantly blocked capsaicin-evoked release of iCGRP. Collectively, these studies demonstrate that activation of β2-adrenoceptors in dental pulp significantly reduces exocytosis of neuropeptides from capsaicin-sensitive nociceptors. This effect may have physiologic significance in regulating PBF. Moreover, since capsaicin selectively activates nociceptors, β2-adrenoceptor agonists may have clinical utility as peripherally acting therapeutics for dental pain and inflammation.

Bradykinin is a potent mediator of pain and inflammation. To examine extracellular levels of bradykinin in human dental pulp, CMA/20 microdialysis probes were inserted into the pulp tissue of 22 teeth diagnosed with normal pulp or with irreversible pulpitis before their extraction or endodontic therapy. Probes were perfused with a modified Locke-Ringer's buffer and bradykinin levels in the dialysate evaluated using a radioimmunoassay. Mean extracellular levels of bradykinin within pulp tissue diagnosed with irreversible pulpitis were significantly higher (262.26 +/- 83.79 fmol/ml) than that found within normal pulp (19.41 +/- 6.47 fmol/ml). Highest levels of bradykinin were detected in pulp tissue diagnosed with irreversible pulpitis when the patient had reported pain in the past, compared with patients who were in pain just before their visit. These observations suggest that the bradykinin system is activated during pulpitis and may contribute to pain and inflammation.

Mediators produced during inflammation are responsible for hyperalgesia and expression of neurotransmitters and receptors in the nervous system. The production of bradykinin (BK) and the prostaglandins (PGs) may regulate initiation of pain. This study tested the hypothesis that BK and prostaglandin E2 (PGE2) have a positive interaction in evoking neurosecretion of immunoreactive calcitonin gene-related peptide (iCGRP). Bovine dental pulp was prepared and stimulated by the superfusion method with BK alone and in combination with PGE2. Kinin receptor antagonists to bradykinin-evoked release of iCGRP were also tested. Also tested was the hypothesis that dental pulp contains cither the B, or B2 or both BK receptors. Results showed that PGE2 enhanced BK-evoked iCGRP release by more than 50%. Western immunoblots revealed detectable B, receptor protein with no detectable B1 receptor protein. We conclude that BK evokes iCGRP release from bovine dental pulp which is enhanced by a positive interaction with PGE2. Neurosecretion is evoked from isolated terminals of dental pulp fibers via the bradykinin B2 receptor-dependent mechanism.

Effective management of endodontic pain represents a continuing challenge. In this study, we evaluated the efficacy of flurbiprofen and a novel centrally acting analgesic, tramadol, alone and in combination, for reducing pain in endodontic emergency patients. Patients (n = 49) were administered a local anesthetic and underwent pulpectomy. They were then administered, on a double-blind basis, either: (i) placebo (one capsule to start and then every 6 h); (ii) flurbiprofen (100 mg loading dose and then 50 mg every 6 h); (iii) tramadol (100 mg loading dose and then 100 mg every 6 h); or (iv) the combination of flurbiprofen and tramadol (as above). Pulpectomy combined with placebo medication resulted in a 50% reduction in pain by 24 h (p < 0.01). Patients treated with flurbiprofen and tramadol reported less pain, compared with placebo treatment at 6 and 24 h (p < 0.01 for both). These results suggest that a nonsteroidal anti-inflammatory drug/opiate combination, together with endodontic therapy, may be useful in the management of endodontic pain.

The rat adrenal capsule and cortex are innervated by primary afferent neurons that contain neuropeptides, including calcitonin gene-related peptide (CGRP; 1). Furthermore, CGRP has been implicated in modulating adrenal cortical function (2–5). These results suggest that factors influencing the release of CGRP from these fibers may represent an additional regulatory system for modulation of adrenal cortical function in vivo. In the present study, we used an in vitro superfusion technique to pharmacologically characterize the release of immunoreactive CGRP (iCGRP) from adrenal capsular sensory fibers. These studies employed capsaicin, the pungent principle of hot peppers, which selectively activates a subset of nociceptive primary afferent neurons (6). In addition, the effects of capsaicin on aldosterone biosynthesis by adrenal capsules were assessed.Briefly, adrenal glands were quickly removed from male, Sprague-Dawley rats (250-275g) and decapsulated. The adrenal capsules were then placed into superfusion...

Initial root canal therapy and implant placement are both common treatment modalities, and, as such, prognostic factors that influence the treatment outcomes of these two restorations should be identified. In a retrospective chart review, 196 implant restorations and 196 matched initial nonsurgical root canal treated (NSRCT) teeth in patients were evaluated for four possible outcomes-success, survival, survival with intervention, and failure. Results showed that smokers had fewer successes and more failures in both groups (p = 0.0001), whereas NSRCT outcomes were affected by periradicular periodontitis (p = 0.001), post placement (p = 0.013), and overfilling (p = 0.003). Outcomes for both groups were not significantly affected by diabetes, age, or gender. Implant group outcomes were not affected by implant length (from 10 to 16 mm), diameter (from 3.25 to 5.5 mm), or an adjacent endodontically treated tooth, nor were NSRCT outcomes affected by the number of appointments for the procedure.

Although pulpal neuropeptides such as calcitonin gene-related peptide and substance P may mediate neurogenic inflammation, little is known about the regulation of neuropeptide release from dental pulp. This article describes an in vitro method for superfusing dental pulp which permits the study of mechanisms regulating the release of immunoreactive CGRP (iCGRP). Tissue extracts from bovine dental pulp dilute in parallel to authentic calcitonin gene-related peptide and substance P peptide standards when assayed by radioimmunoassay. Pulpal levels of iCGRP were 17-fold greater than levels of immunoreactive substance P. Administration of a potassium pulse evoked a significant release of iCGRP from dental pulp (155 +/- 21 fmol/g/9 min) as compared with iCGRP spontaneously released from concurrent control chambers (18 +/- 11 fmol/g/9 min). The in vitro superfusion of pulp tissue may serve as a useful method for identifying peripherally acting drugs which modulate nociceptor secretory activity and for determining their mechanisms of action.