Cardiac Platypnea-Orthodeoxia Syndrome: A Rare Case of Flow-Directed, Right-to-Left Shunt via a Patent Foramen Ovale Exacerbated by Aortic Root Enlargement.

Cardiac platypnea-orthodeoxia is a unique clinical syndrome characterized by dyspnea and deoxygenation when moving from a supine to an upright position. In this case report, we detail the experience of a 78-year-old male with persistent hypoxemia following a paradoxical embolic ischemic stroke. Despite proper management of his respiratory symptoms, the patient continued to be affected by marked dyspnea and hypoxemia, particularly when upright or in a right-sided decubitus position. Subsequent investigation revealed that his hypoxemia was a result of cardiac platypnea-orthodeoxia syndrome (POS). This condition was attributed to the enlargement of his aortic root and ascending aorta, coupled with a counterclockwise rotation of the heart axis. These factors facilitated a flow-directed, right-to-left interatrial shunt through a patent foramen ovale, even in the absence of elevated right heart pressures.

Successful Treatment of Severe Paravalvular Leak by Repositioning a Self-Expandable Percutaneous Aortic Valve Bioprosthesis (Evolut PRO+) Using the "Double Snare" Technique.

Significant (moderate or severe) paravalvular leak (PVL) after transcatheter aortic valve replacement (TAVR) remains a common phenomenon and has been associated with decrease survival and quality of life. Transcatheter valve embolization and migration (TVEM) is a rare post-TAVR complication that can occur in 1% of cases and has been associated with worse patient outcomes. Valve embolization or migration into the left ventricle can result in significant PVL causing hemodynamic instability, shock, heart failure, and hemolytic anemia. Although this complication most commonly occurs in the acute setting (90%) within 4 hours of TAVR, it can also present late (4 hr-43 days later) in 10% of cases. There are no clear guidelines as to how this condition should be managed; however, several percutaneous bailout techniques exist that can ultimately spare the patient from emergent cardiovascular surgery. We present a rare case of late ventricular transcatheter aortic valve migration 3 days after TAVR causing severe PVL and heart failure symptoms that was successfully treated using the percutaneous "double snare" technique.

Doses in eye lens, thyroid, and gonads, due to scattered radiation, during a CT radiodiagnosis study.

X-ray images used for radio-diagnosis are very useful to evaluate the progress of a treatment or to have a better diagnosis. However, during the interaction between the incoming X-ray beam and the body surface, part of the radiation is scattered out reaching other parts of the body delivering an undesirable dose. In this work the dose in eye lenses, thyroid, and gonads of a solid water phantom was measured using thermoluminescent dosimeters, while a Computer Tomography of the torso was obtained. With the measured absorbed dose the effective dose was calculated. Thus, the effective dose in the eye lens, thyroid, and gonads is approximately 57, 214 and 9 µSv respectively. The largest effective dose was on that area located nearest to the region where the radiation is scattered.

H*(10) due to scattered radiation on the cancer-patient bodies treated with Tomotherapy.

The ambient dose equivalent has been measured on the walls of a bunker with a 6 MV TomoLINAC, which was designed to have a conventional 18 MV LINAC. The ambient dose equivalent is due to scattered photons on patient bodies during cancer treatment. Measurements were carried out with thermoluminescent dosimeters that were fixed, at the isocentre plane, on the primary and secondary barriers, the maze, and on the TomoLINAC surface. Measurements were repeated three times, in each time dosimeters were on place during seven working days, where approximately 50 patients were treated per day. Ambient dose equivalent at each location was normalized to the total dose applied during the measuring time. The primary and secondary concrete barriers are thick enough to reduce the dose to safe values.

Buffered 1% Lidocaine With Epinephrine Can Be as Effective as Nonbuffered 2% Lidocaine With Epinephrine for Maxillary Field Block.

PURPOSE: Buffering local anesthetics with epinephrine (Epi) offers clinicians options not often considered. This study assessed outcomes for pulpal anesthesia, pain on injection, and time to midface numbness for buffered 1% lidocaine with 1:100,000 Epi versus nonbuffered 2% lidocaine with 1:100,000 Epi. MATERIALS AND METHODS: In this trial with a randomized, crossover design, buffered 1% lidocaine was compared with nonbuffered 2% lidocaine. Subjects were adult volunteers who served as their own controls. The predictor variables were alternate drug formulations. The outcome variables were subjects' responses to cold and electric pulp testing (EPT) stimulation of the maxillary first molar and canine, pain levels during the injection, and time to midface numbness. After maxillary field blocks with 40 mg of buffered lidocaine or 80 mg of nonbuffered lidocaine, subjects reported pain on injection and responses of the maxillary first molar and canine after cold and EPT stimulation. Teeth were tested before field block and at 30-minute intervals until a positive response was detected. Two weeks later, subjects were tested with the alternate drug combinations. For all outcome variables, assessment of treatment difference, calculated as 1% buffered minus 2% nonbuffered, was performed with the Wilcoxon rank sum test with significance at P < .05. RESULTS: More of the 24 subjects were women and Caucasian. The median age was 23.5 years (interquartile range, 21, 25 years), and the median body weight was 155 lb (interquartile range, 128.5, 176.5 lb). Pain levels during the injection were significantly lower for 1% buffered lidocaine, with P = .04. Times to response after injection were not significantly different between the 2 drug formulations for the cold test on a molar, with P = .08, or the cold test on a canine, with P = .22. However, times to response were significantly longer for nonbuffered drugs for EPT on the molar and canine, both with P = .01. CONCLUSIONS: Buffering 1% lidocaine with 1:100,000 Epi reduces the pain on injection with a maxillary field block and results in similar lengths of pulpal anesthesia tested with a cold stimulus as compared with nonbuffered 2% lidocaine with 1:100,000 Epi.

Buffered 1% Lidocaine With Epinephrine Is as Effective as Non-Buffered 2% Lidocaine With Epinephrine for Mandibular Nerve Block.

PURPOSE: To assess outcomes for pulpal anesthesia and pain on injection for buffered 1% lidocaine with 1:100,000 epinephrine (EPI) versus non-buffered 2% lidocaine with 1:100,000 EPI. PATIENTS AND METHODS: In a randomized cross-over trial approved by the institutional review board, buffered 1% lidocaine with 1:100,000 EPI was compared with non-buffered 2% lidocaine with 1:100,000 EPI. After mandibular nerve block with buffered lidocaine 40 mg or non-buffered lidocaine 80 mg, patients reported responses at the mandibular first molar and canine after cold and electrical pulp testing (EPT). Patients also reported pain on injection with a 10-point Likert-type scale. Teeth were tested before nerve block and at 30-minute intervals until a positive response returned. Two weeks later, patients were tested with the alternate drug combinations. The same outcomes were assessed. Predictor variables were alternate drug formulations. Outcome variables were patients' responses to cold and EPT stimulation of the mandibular first molar and canine and pain on injection. An assessment of treatment difference was performed using Wilcoxon rank-sum tests with Proc NPAR1WAY (SAS 9.3, SAS Institute, Cary, NC). Significance was set at a P value less than .05. RESULTS: Fifty-seven percent of patients were women and 43% were men. Seventy percent were Caucasian, 17% were African American, and 13% had another ethnicity. Median age was 25 years (interquartile range [IQR], 21-26 yr) and median body weight was 140 lbs (IQR, 120-155 lbs). After the cold test and EPT, the time to sensation return for the molar or canine was not statistically different between the 2 drug formulations. Patients reported significantly lower pain scores with the buffered versus non-buffered drug (P < .01). CONCLUSIONS: After mandibular nerve block, buffered 1% lidocaine with EPI can produce similar clinical outcomes for duration of pulpal anesthesia as non-buffered 2% lidocaine with EPI and lower pain on injections, which are a potential benefit to patients.

Cone-beam Computed Tomography Uses in Clinical Endodontics: Observer Variability in Detecting Periapical Lesions.

INTRODUCTION: The accurate interpretation of a cone-beam computed tomographic (CBCT) volume is critical in identifying the presence of disease correctly and consistently. The aim of this clinical study was to determine the effect of experience level on the detection of periapical lesions in CBCT volumes. METHODS: CBCT volumes of 22 maxillary molars were interpreted by 3 endodontic faculty, 3 endodontic residents, and 3 dental students. These groups were compared with the consensus opinion of 2 experienced oral and maxillofacial radiologists. The observers determined the presence or absence of apical radiolucencies for each root using a 5-point Likert scale. RESULTS: Compared with the radiologists, the average weighted kappa value for endodontic faculty was 0.49, for endodontic residents it was 0.35 and for dental students it was 0.32. Intrarater reliability for each group showed endodontic faculty having the highest average weighted kappa value of 0.68 followed by endodontic residents (0.48) and dental students (0.28). CONCLUSIONS: Clinicians' experience level appears to be correlated with their ability to correctly diagnose periapical disease in CBCT volumes. In addition, experience leads to better inter-rater reliability. In neither of these 2 categories was agreement found to be excellent, suggesting that more can be done to improve the CBCT interpretation skills of clinicians at various levels of experience.

Genotoxic assessment of the copper chelated compounds Casiopeinas: Clues about their mechanisms of action.

Casiopeinas is the generic name of a group of copper chelated complexes designed to be used as antineoplastic. Some of these compounds have shown promising results, and in fact, one of them named Casiopeina III-ia has completed preclinical trials and is ready to start clinical phase I in Mexico. As part of the tests that have to be done to every molecule intended to be used in humans, bacterial assays are required because of their sensitivity, speed and reproducibility and among them, Ames test and the SOS Chromotest are widely used to evaluate DNA damage. With the aim to contribute to complete safety information related to genotoxicity and support the hypothesis about their mode of action, four different Casiopeinas (Cas II-gly, Cas III-Ea, Cas III-ia and Cas III-Ha) were tested for genotoxicity with these assays, as well as differential cytotoxicity upon Escherichia coli mutants defectives in some DNA repair mechanisms. However, although it is well known that these molecules produce DNA breakage, the results of the Chromotest and Ames test were negative. Despite this is controversial, a possible explanation is that there is a direct interaction between DNA and the Casiopeinas tested.

Utilization of blended learning to teach preclinical endodontics.

Blended learning (BL) is the integration of classroom learning with an online environment. The purpose of this study was to determine whether dental students who experienced BL in a preclinical endodontic course demonstrated better manual skills, conceptual knowledge, and learning experience compared to those experiencing traditional learning. All eighty-one students (100 percent) in a preclinical endodontics course agreed to participate and were assigned to either the traditional or BL group. A root canal procedure was used to determine the level of manual skills gained by each group. Pre- and post-intervention quizzes were given to all students to evaluate conceptual knowledge gained, and the students' perspectives on the methods were evaluated with a survey. The BL group scored better than the traditional group on the manual skills exercise at a statistically significant level (p=0.0067). There were no differences in the post-intervention quiz scores between the two groups, and the students' opinions were positive regarding BL. With BL, the students were able to learn and demonstrate dental skills at a high level.

Access to endodontic care in North Carolina public health and Medicaid settings.

OBJECTIVES: The purpose of this study was to investigate issues related to access to endodontic care in North Carolina for individuals who used dental public health resources such as public health clinics (PHCs) or private practices that accept Medicaid or other government-sponsored reimbursement programs private practices that accept Medicaid (PPM). METHODS: Surveys were sent to 1,195 dentists regarding frequency and type of endodontic conditions encountered, treatments provided, and perceived barriers to care. Results were analyzed using logistic regression with the level of significance set at 0.05. RESULTS: Five hundred forty-six surveys were returned for a 45.7% response rate. Of the respondents, 79% reported frequently encountering an endodontic condition, but only 34% reported performing any type of definitive endodontic procedure. Graduates after the year 2000 were significantly more likely to perform definitive endodontic procedures (P < 0.05). Lack of insurance was the greatest barrier to care with 89% considering it a moderate to major barrier, followed by cost of the endodontic treatment (87%) and cost of the restoration following treatment (86%). PPMs were more likely to consider cost and insurance a major barrier (P < 0.05). CONCLUSIONS: In North Carolina public health and Medicaid settings, the frequency of endodontic treatments provided was much lower than the frequency of endodontic conditions encountered that might have benefited from treatment. Graduation year was the best indicator for the provision of root canal therapy. Additionally, treatment patterns and perceptions of barriers to care are different for PHCs and PPMs.

Comparative Resistance of AH26 and a New Sealer Prototype to a Bacterial Challenge.

Objective. This study compared the leakage resistance of a New Sealer Prototype (NSP) with a traditional sealer (AH 26) in Resilon-filled roots subjected to a bacterial challenge. Study Design. 41 roots were instrumented to ISO size 50 apically. Group 1 (n = 20) contained Resilon and AH 26 sealer and roots in group 2 (n = 21) contained Resilon and NSP. Roots were embedded in a dual-chamber model with the upper chamber containing Streptococcus mutans inoculum. Evidence of bacterial penetration was observed for 1 month. Fisher's Test was used to analyze the data. Results. 8 of 20 roots (40%) in the AH 26 group demonstrated leakage whereas 3 of 21 roots (14%) in the NSP group leaked. The difference in leakage rates was not statistically significant (P = 0.053). Conclusion. The traditional sealer (AH 26) demonstrated increased leakage rates compared to the New Sealer Prototype (NSP), but the difference did not reach statistical significance in this study.

Evaluating the paper point technique for locating the apical foramen after canal preparation.

OBJECTIVE: Despite not having been formally evaluated in the endodontic literature, claims have been made regarding the acceptability of the paper point technique (PPT) in estimating the location of the apical foramen (AF). Our aim was to investigate the repeatability and accuracy of PPT in estimating AF location in a cohort of dental patients. STUDY DESIGN: Root canals with

Aromaticity at the water-hydrocarbon core interface of the membrane: consequences on the nicotinic acetylcholine receptor.

Almost all lipid-exposed transmembrane domains of integral proteins contain aromatic residues flanking the hydrophobic segment of the domains. These residues generally reside close to the carbonyl region of the membrane, and several structural and functional roles have been associated to these residues. Although the roles and physicochemical reasons for aromatic preference have been extensively studied using model systems, few studies have been done in a native membrane system. To gain insight about the mechanistic implication for this aromatic preference, we selected position alpha F426 of the muscle-type nicotinic acetylcholine receptor (nAChR). alpha F426 is a lipid-exposed residue at the extracellular segment of the alpha M4 transmembrane domain and is highly conserved among different nAChR subunits and species. We used site-directed mutagenesis, alpha-Bungarotoxin-binding assay, and two-electrodes voltage clamp in Xenopus laevis oocytes to characterize mutations at position alpha F426, which impart different physicochemical properties like volume, polarity, hydrogen bonds, aromaticity and net electrical charge. All mutations except the aromatic residues resulted in a significant reduction of the nAChR cell-surface levels and the macroscopic currents to acetylcholine. These results suggest that position alpha F426 contributes to structural stability and open-close transitions of the nAChR. Finally, the present study also provides information about how intermolecular interactions at position alpha 426 modulate open-close transitions of the nAChR.

A six year evaluation of cracked teeth diagnosed with reversible pulpitis: treatment and prognosis.

The purpose of this investigation was to report on the clinical outcomes of cracked teeth diagnosed with reversible pulpitis (RP). Eight thousand one hundred seventy-five patients referred for evaluation and treatment during a 6-year period had medical and dental histories, radiographs, pulpal and periapical diagnosis, periodontal probings, direct identification of crack(s) with transillumination, and biting responses on various cusps recorded. All data were stored daily in a database. All cases were treatment planned according to the pulpal and periapical diagnosis. Cases with RP were treatment planned for crowns only, regardless of periapical diagnosis. All patients were recalled at 1 year unless root canal treatment was needed before the anniversary. Results indicated that cracks were identified in 9.7% (796 of 8175) of all teeth evaluated during this time period. Of 127 patients specifically diagnosed with RP, 27 converted to irreversible pulpitis (N = 21) in 58 days or to necrotic pulp (N = 6) in 149 days. To date, none of the original remaining 100 cases of RP have required root canal treatment. The outcomes of this study suggest that if a marginal ridge crack is identified early enough in teeth with a diagnosis of RP and a crown is placed, root canal treatment will be necessary in about 20% of these cases within a 6-month period.

Effectiveness of mouthguards in reducing neurocognitive deficits following sports-related cerebral concussion.

Although it is widely accepted that mouthguards decrease the incidence of dental injuries, there is a controversy among sports medicine professionals as to the effectiveness of mouthguards in decreasing the incidence or severity of sports-related cerebral concussion (SRCC). While some experimental data suggest that this may be the case, there exist a number of reports suggesting that mouthguards do not serve this purpose. These conclusions have been drawn, however, without actually measuring the extent of neurocognitive dysfunction in athletes following sports-related concussion. The purpose of this study was to determine whether mouthguard use reduces the neurocognitive and symptomatic impairments that follow an injurious episode of SRCC. Preseason baseline data were collected as part of an ongoing clinical program that uses a computerized neurocognitive test to assess various faculties of brain function and symptoms reported at the time of testing. Follow-up testing from 180 student-athletes who had sustained an SRCC was analyzed for the purpose of this study. These athletes were separated into one of two groups: those who reported using mouthguards and those who did not. Neurocognitive testing was accomplished using the Immediate Post-Concussion and Assessment Test (ImPACT). Results suggest that neurocognitive deficits at the time of the athletes' first follow-up assessment did not differ between mouthguard users and non-users, suggesting that mouthguard use does little to reduce the severity of neurocognitive dysfunction and onset of symptoms following sports-related head trauma. However, an interesting finding in this study was that athletes experienced significantly lower neurocognitive test scores and reported higher symptom scores following SRCC regardless of mouthguard use. This emphasizes a thorough clinical evaluation of athletes that have sustained an SRCC. Although it was found in this study that mouthguard use does not decrease the severity of concussion, it is important to note that the use of mouthguards is paramount in reducing maxillofacial and dental trauma and their use should continue to be mandated by athletic associations and supported by all dental and sports medicine professionals.

In vitro assessment of local computed tomography for the detection of longitudinal tooth fractures.

OBJECTIVE: To test the accuracy of local computed tomography (LCT) in detecting longitudinal fractures in comparison with conventional periapical radiographs. STUDY DESIGN: Longitudinal fractures were induced in 30 of 60 teeth. The teeth were placed in a dry dentate mandible with soft tissue simulation. A laboratory LCT unit was used to acquire 180 basis projections with 1 degree separation along a 180 degree arc. Conventional radiographs served as the control modality. Correlated axial, coronal, and sagittal views were presented to 10 observers. The observers determined the presence of a root fracture by using a 5-point receiver operating characteristic confidence scale. RESULTS: The mean A(z) for LCT was 0.91 (SD = 0.07). The mean A(z) for conventional radiography was 0.70 (SD = 0.07). The difference between the modalities was statistically significant (analysis of variance: P < .0002), whereas the differences between the observers was not (analysis of variance: P = .319). CONCLUSION: Local CT significantly improves the detection of longitudinal fractures in vitro compared with conventional periapical radiography.

Perflutren microspheres for contrast echocardiography in a bloody pericardiocentesis.

We report the cases of 2 patients who presented with clinical and echocardiographic evidence of cardiac tamponade. Therapeutic echocardiographic-guided pericardiocentesis yielded bloody fluid. In both patients, Definity perflutren lipid microspheres were used for echocardiographic contrast, which helped to assess the needle's location. To the best of our knowledge, this is the 1st reported use of perflutren microspheres for this purpose.

Prosthetic valve endocarditis.

Prosthetic valve infective endocarditis represents a defined pathological entity which follows an epidemiological and nosological pattern in accordance to an arbitrary classification. Chronologically it is divided into the entities of early and late prosthetic valve endocarditis, each with its own unique characteristics. The clinical features, complications and diagnosis do not vary much from native valve endocarditis. There are clear and precise indications to aid in the diagnosis and treatment of this entity which differ from native valve endocarditis.

Effect of root canal filling/sealer systems on apical endotoxin penetration: a coronal leakage evaluation.

Endotoxin, elaborated by gram-negative organisms, is an important factor in apical periodontitis. The objective of this study was to evaluate the magnitude of endotoxin penetration through root canal treated teeth using a dual chamber model system. Forty-four maxillary anterior teeth were prepared endodontically and canals filled either by lateral condensation or a warm thermoplasticized technique in combination with either Roth's 801 or AH 26 sealer. Teeth were suspended in the model system with a mixed anaerobic bacterial suspension in the upper chamber and HBSS in the lower chamber. The QCL-1000 LAL assay was used to measure endotoxin at 0, 1, 7, 14, and 21 days. Response feature analysis using trapezoidal area under the curve was performed; the four treatment groups were compared using nonparametric methods. Groups differed (p = 0.028), with thermoplasticized root canal filling/Roth's 801 sealer permitting the least apical endotoxin penetration. Results suggest that Roth's 801 sealer may have a role in inhibiting endotoxin penetration.

A comparison of dental services received by Medicaid and privately insured adult populations.

BACKGROUND: Few studies have compared differences in dental care utilization rates between a publicly and a privately insured adult population in the same geographic area. The authors conducted this study to compare the demographic characteristics and use of dental services for enrollees in the Iowa Medicaid program and in the Delta Dental Plan of Iowa. The focus was on the overall use of dental services, with an emphasis on the use of tertiary care services such as endodontic therapy and tooth extraction services. METHODS: The authors used insurance claims data for adults aged 21 to 64 years who were enrolled in Delta Dental of Iowa and the Iowa Medicaid program for fiscal year 1998. They calculated utilization of dental services rates by type of dental procedure. RESULTS: In fiscal year 1998, 69.3 percent of Delta Dental enrollees and 27.2 percent of Medicaid enrollees had a dental visit. More than 90 percent of those in both populations with a dental visit had used preventive dental services during the year. Medicaid users were nearly twice as likely as Delta Dental enrollees to receive endodontic therapy (9.9 percent versus 5.0 percent, respectively) and nearly four times as likely to have had a tooth extracted (27.4 percent versus 7.1 percent, respectively). CONCLUSIONS: Privately insured enrollees were more likely to use dental services that were Medicaid enrollees. The greater use of tertiary care services by the Medicaid population than by the privately insured population is indicative of a lower oral health status for this group at the time they sought care, even though it was a much younger group of adults. PRACTICE IMPLICATIONS: The oral health status of low-income adults enrolled in Medicaid could benefit greatly from higher use of routine preventive dental services and earlier treatment of oral diseases to prevent the substantial need for preventable tertiary care services.