bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microf racture Mechanisms of Dental Resin Composites Containing Spherically-shaped Filler Particles
Authors: Kim K.H. , Park J.H. , Imai Y. , Kishi T. 
Published: July 2017

The effects of spherically-shaped filler particles on bending strength, bending elastic modulus, and fracture toughness of resin composites were studied. The filler content was changed by 0, 20, 40, 60, and 70 wt%. Bending properties and fracture toughnesses were determined on three-point bending specimens. Acoustic Emission (AE), i.e., the elastic wave released from a localized source in the material, was detected by sensors of a high-sensitivity and low-noise resonance type during the fracture toughness test. Detected acoustic emission signals were analyzed for parameters such as amplitude, events, and locations. The fractured surf ace was examined by a scanning electron microscope. The bending strength and the fracture toughness showed almost the same trend in their increasing rates by filler content, but the elastic modulus showed a much higher increasing rate. A microfracture mechanism of the dental resin composites containing spherically-shaped filler particles is proposed based on the results obtained from the AE-releasing pattern, two-dimensional AE location, and fracture surface findings. In addition to the toughening effects of crack pinning and crack branching, which are observed in the usual commercial resin composites, crack-deflecting effects are confirmed in this new type of dental resin composites.
Effects of Dentin Surface Treatments on the Fracture Toughness and Tensile Bond Strength of a Dentin-Composite Adhesive Interface
Authors: Tam L.E. , Pilliar R.M. 
Published: July 2017

It has been proposed that the fracture toughness test provides an appropriate method for assessing the fracture resistance of the dentin-composite interface. The plane-strain fracture toughness test was therefore applied to a dentin-composite interface, with use of a specific dentinal adhesive, so that the effects of various dentin surface treatments on dentin-bond integrity could be studied. Interfacial fracture toughness (KIC) values were determined following 24 h and 180 days of specimen aging in distilled water at 37*C. Tensile bond strength (TBS) results following 24-hour aging were also obtained for comparison with the 24-hour KIC results. In general, the fracture resistance of the dentin-composite interface was highest when the dentin surface was conditioned with acid but not air-dried, intermediate when the dentin surface was conditioned with acid and subsequently air-dried, and lowest when the dentin was not conditioned with acid. The tensile bond strength results differed from the fracture toughness results in indicating differences in surface preparation effects and the type of interfacial failure observed.
Ethical Use of Animals
Authors: Bowen W.H. 
Published: July 2017

Based on old nursery rhymes, which are still in vogue, it is apparent that children from an early age receive ambivalent messages concerning relationships with animals. It is also apparent that we as a society have placed a hierarchical structure on animals; it is clear that we value a dog or a cat more than a mouse or a rat. Enormous strides in the prevention and treatment of disease have been made directly or indirectly as a result of experiments carried out on animals. Persons who conduct investigations using animals have an obligation to ensure that valid scientific questions are being explored, and that the minimum numbers of animals are used compatible with achieving a valid scientific result. Animals must always be cared for properly. Research involving induction of pain must receive particular attention. Finally, it is incumbent upon all scientists who use animals in their investigations to ensure that the public is kept fully informed of all scientific advances made by the use of animals.
Dye-enhanced Ablation of Enamel by Pulsed Lasers
Authors: Jennett E. , Motamedi M. , Rastegar S. , Frederickson C. , Arcoria C. , Powers J.M. 
Published: July 2017

Laser removal of dental hard tissue has been proposed as a replacement for or augmented approach to the dental handpiece. The main limitation for widespread usage of lasers in dentistry has been inefficient ablation of dental hard tissue, accompanied by potential laser-induced damage to the surrounding tissue. The research focuses on a novel approach for enhancement of tissue ablation and confinement of laser interaction to a small tissue volume by controlled placement of an exogenous dye on the enamel surface. Studies were done with both pulsed alexandrite and pulsed Nd:YAG lasers, with indocyanine green and India ink, respectively, used as photo-absorbers. These dye-enhanced laser processes demonstrated the feasibility of this technique for cavity preparation. While control studies produced little or no appreciable crater, average preparation depth for the dye-enhanced ablation was from 1 to 1.5 mm, with a diameter of approximately 0.6 mm. Knoop hardness measurements show that, surrounding the crater, there is a small annular region slightly softened by the laser action. SEM studies of the interior structure of the tooth did not show significant damage to the surrounding tissue. Temperature measurement studies indicated that the pulsed nature of the laser, combined with the photoabsorbing dye, effectively prevented significant temperature rise at the pulp. The remarkable effectiveness of this technique in creating cavity preparations and the absence of any notable collateral damage to the surrounding tissue suggest that dye-enhanced pulsed-laser ablation could be used as an alternative to the dental handpiece in selected procedures.
Prevalence and Distribution of Selected Occlusal Characteristics in the US Population, 1988–1991
Authors: Brunelle J.A. , Bhat M. , Lipton J.A. 
Published: July 2017

The inclusion of occlusal traits as part of the oral health component of the Third National Health and Nutrition Examination Survey, Phase 1, 1988–91, provided an opportunity to assess several occlusal characteristics in the US population: diastema ≥ 2 mm, alignment of lower and upper anterior teeth, posterior crossbite, overbite, and overjet. Household questionnaires asked whether the individual had ever received orthodontic treatment. Prevalence of clinical measures of occlusal characteristics and orthodontic treatment was estimated for over 7,000 sample persons from 8 to 50 years of age, representing approximately 150 million non-institutionalized people in the United States. These findings present the first estimates of occlusal status of the US non-institutionalized population in more than 25 years. Eight percent of the population had severe overbite of 6 mm or more. The average overbite was 2.9 mm. Maxillary diastemas ≥ 2 mm were observed in 19% of 8-11-year-olds, 6% of 12-17-year-olds, and 5% of adults 18-50 years old. Twenty-five percent and 22% of persons had zero mm of malalignment in maxillary and mandibular incisors, respectively. Conversely, 11% and 15% of persons had 6 mm or more displacement of maxillary and mandibular molars, respectively. Posterior crossbite affects less than 10% of this population, and less than 10% had overjet of 6 mm or more. Non-Hispanic black adults had the least amount of malalignment in mandibular incisors. Three times as many non-Hispanic blacks compared with non-Hispanic whites and Mexican-Americans had diastemas ≥ 2 mm. Comparisons with published data from the National Health Examination Survey (1966–70) indicated a 20% increase of 12-17-year-olds with overbite in the normal range (0-3 mm). Almost 20% of adults ages 18-50, as well as 18% of children, have had orthodontic treatment.
A Functional Approach to Lateral Fixation in Bilateral Abductor Cord Paralysis
Authors: Amedee Ronald G. , Mann Wolf J. 
Published: July 2017

A modification of the Clerf arytenoldopexy treatment for bilateral vocal cord paralysis is described; It consists of an external approach with complete unilateral division of the posterior cricoarytenoid and Interarytenold muscles. The entire arytenoid Is next mobilized and tilted laterally, then fixed Into position along the posterior margin of the thyroid cartilage by two or three permanent retention sutures. Careful placement of these sutures renders the laryngeal mucosa maximally undisturbed and Is largely responsible for the predictable results achieved with this technique. During the past 2 years, 18 patients received this static procedure, and 17 of 18 (94%) required a tracheotomy as part of the treatment because of a uniformly severe degree of glottic obstruction. All tracheotomy patients have been permanently decannulated (on an average) 14 days after surgery. The evaluation of each patient Included pre‐ and postoperative measurements of airway resistance that correlated well with the width of the posterior commissure, and proved Invaluable in successful decannulation efforts.
Electrophysiologic Assessment of Low‐Frequency Hearing: Sedation Effects
Authors: Palaskas Constantine W. , Wilson Michael J. , Dobie Robert A. 
Published: July 2017

Sixteen normal‐hearing adults were tested in both awake and sedated states for several evoked responses to low‐frequency stimuli. Responses obtained by cross‐correlation function, middle latency responses, and the 40‐Hz response proved most sensitive; all had mean thresholds of less than 20 dB normal hearing level for the awake‐alert state, but 40‐Hz and middle latency response mean thesholds were shifted about 10 dB under sedation. The cross‐correlation method seems to offer promise for pediatric auditory assessment.
Instant Slides of Radiographs for Lectures
Authors: Rothstein Stephen G. , Stewart Patricia L. 
Published: July 2017

High quality slides of radiographs may be made with a simple, fast, and inexpensive technique using Kodak Rapid Process Copy film. Lecture presentations may include a slide of a pertinent plain radiograph, computed tomography (CT) scan, or magnetic resonance imaging (MRI). Although these slides may be made with a 35 mm SLR camera and flash or with a 35 mm SLR camera and a lighted viewbox, an alternative method is available that is easy to perform, inexpensive, and can produce quality slides in as little as 30 minutes.
Progesterone Receptors in Carcinomas of the Upper Aerodigestive Tract
Authors: Berg Nicholas J. , Colvard Douglas S. , Neel H. Bryan , Weiland Louis H. , Spelsberg Thomas C. 
Published: July 2017

This study had three major goals: (1) to vigorously verify the presence of progesterone receptors in squamous cell carcinoma of the upper aerodigestive tract (HN‐SCC). Antiprogesterone receptor monoclonal antibodies revealed a distinct band at approximately 120 kilodaltons in samples taken from two of four patients with HN‐SCC. These results illustrate that progesterone receptor in HN‐SCC has the same molecular weight as progesterone receptor in normal human uterus and human breast cancer. Steroid specificity and saturability results support the evidence that it is true progesterone receptors that are measured and not other receptors or sex steroid‐binding globulins; (2) to confirm the biochemical function of progesterone receptors in HN‐SCC by assessing the binding of progesterone receptor to acceptor sites on chromosomes in the nucleus; and (3) to establish the clinical significance of progesterone receptor measurement. Patients with positive assays were more likely to be free of disease a mean of 6 months after resection. We used logistic regression to account for site of primary disease, grade of tumor, and stage of disease. This logistic regression was significant with a p = 0.014. Patients with a binding index greater than 2 (19 of 73 patients) were 4.34 times more likely to be free of disease than patients with negative assays.
Pathologic Correlation of the Unknown Solid Parotid Mass in Children
Authors: Camacho Alfonso E. , Goodman Max L. , Eavey Roland D. 
Published: July 2017

A parotid mass in a pediatric patient is stated to have an approximately 50% likelihood of being malignant.1,2 To evaluate our experience in light of this suggested incidence, we conducted a retrospective study, which included 22 patients treated over an 8‐year period, 1979 to 1987. Patients' ages ranged from 16 months to 19 years, and all patients presented with an unknown, solid parotid mass. One patient had a malignancy, mucoepidermoid carcinoma. Eight patients were diagnosed with benign pleomorphic adenoma. Thirteen patients had an inflammatory process consisting of one of the following conditions: Cat‐scratch disease (4); atypical mycobacteria (4); benign follicular hyperplasia of a lymph node (4); and toxoplasmosis (1). The histologic findings in this series suggest that unknown solid parotid masses that occur in children or adolescents are frequently the result of inflammatory conditions and are not likely to be malignant. We therefore recommend a reconsideration of the reputed estimation of malignancy in the parotid gland in children. The majority of pathologic conditions discovered, however, are still best diagnosed and treated by surgical excision.
A Biomechanical Comparison of Tibial Inlay and Tibial Tunnel Posterior Cruciate Ligament Reconstruction Techniques
Authors: McAllister David R. , Markolf Keith L. , Oakes Daniel A. , Young Charles R. , McWilliams Justin 
Published: July 2017

Background Most posterior cruciate ligament reconstruction techniques use a tibial bone tunnel, which results in an acute bend in the graft as it passes over the posterior portion of the tibial plateau. Hypothesis The tibial inlay technique will result in lower graft pretensions, less laxity, and less stretch-out after cyclic loading. Study Design Controlled laboratory study. Methods Graft pretensions necessary to restore normal laxity at 90° of knee flexion (laxity match pretension) and anteroposterior laxities at five knee flexion angles were recorded in 12 fresh-frozen knee specimens with bone-patellar tendon-bone posterior cruciate ligament graft reconstructions using both techniques and two femoral tunnel positions. Results When the graft was placed in a central femoral tunnel, the tibial tunnel reconstruction required an average 15.6 N greater laxity match pretension than the tibial inlay reconstruction. There were no significant differences in mean knee laxities between the tibial tunnel and tibial inlay techniques at any knee flexion angle; both reconstruction techniques restored mean knee laxity to within 1.6 mm of intact knee values over the entire flexion range. Conclusions There was no important advantage of one technique over the other with respect to the biomechanical parameters measured.
Arthroscopic Laser-Assisted Capsular Shift in the Treatment of Patients with Multidirectional Shoulder Instability
Authors: Favorito Paul J. , Langenderfer Matthew A. , Colosimo Angelo J. , Heidt Robert S. , Carlonas Richelle L. 
Published: July 2017

Background In recent years, various investigators have begun using lasers in the treatment of shoulder instability. Hypothesis Arthroscopic laser-assisted capsular shift is an effective treatment for patients with multidirectional shoulder instability. Study Design Retrospective cohort study. Methods We retrospectively identified 28 patients (30 shoulders) with multidirectional shoulder instability who were unresponsive to nonoperative management and who had undergone the laser-assisted capsular shift procedure. Twenty-five patients (27 shoulders) with an average follow-up of 28 months were available for review. All patients underwent a physical examination and completed a general questionnaire; the University of California, Los Angeles, shoulder rating scale; the Western Ontario Shoulder Instability Index; and the Short-Form 36 quality of life index. Results In 22 shoulders, results of the procedure were considered a success because the patients had no recurrent symptoms and at latest follow-up had required no further operative intervention. In five shoulders, results were considered a failure because of recurrent pain or instability and the need for an open capsular shift procedure. With recurrent instability as a measure of failure, the overall success rate was 81.5%. Conclusions Our results with laser-assisted capsular shift are comparable with the results of other open and arthroscopic techniques in relieving pain and returning athletes to their premorbid function.
Differences in Femoral Notch Anatomy between Men and Women
Authors: Charlton William P. H. , John Thomas A. St. , Ciccotti Michael G. , Harrison Nichol , Schweitzer Mark 
Published: July 2017

Background Research has shown that variations in femoral intercondylar notch morphometry may be a predisposing factor for noncontact anterior cruciate ligament injury. Hypothesis There are anatomic differences in the anterior cruciate ligament and femoral notch between men and women. Study Design Descriptive anatomic study. Methods Using magnetic resonance imaging, we performed a three-dimensional analysis of the femoral intercondylar notch morphometry to look for differences in femoral notch and anterior cruciate ligament volumes between men and women. Axial plane magnetic resonance imaging scans were performed on 96 knees in 48 asymptomatic subjects. Digital measurements were taken of femoral notch area, anterior cruciate ligament area, notch width, and bicondylar width, within defined parameters of the femoral notch. The notch and anterior cruciate ligament volumes were then calculated. Analysis of variance was performed using sex, height, and weight as covariates. Results The volume of the femoral notch was found to be statistically smaller in women compared with men; this difference was primarily related to height. A similar relationship was found for anterior cruciate ligament volume. A statistically significant correlation was found between femoral notch volume and anterior cruciate ligament volume; patients with smaller notches also had smaller anterior cruciate ligaments. Conclusions Our results suggest that there is a difference in femoral notch and anterior cruciate ligament volume between men and women, which, in turn, is related to differences in height and weight.
Retroversion of the Humerus in the Throwing Shoulder of College Baseball Pitchers
Authors: Osbahr Daryl C. , Cannon David L. , Speer Kevin P. 
Published: July 2017

Background Increased external rotation and decreased internal rotation have been noted to occur progressively in the throwing shoulder of baseball pitchers. Hypothesis Proximal remodeling of the humerus contributes to the rotational asymmetry between shoulders in pitchers. Study Design Descriptive anatomic study. Methods Both shoulders of 19 male college baseball pitchers were evaluated and retroversion of the humerus calculated by using the technique of Söderlund et al. Measurements were taken of passive glenohumeral external rotation at 0° and 90° of abduction and internal rotation at 90° of abduction under a 3.5-kg load. Subjects completed a questionnaire on the amount and duration of overhead throwing performed during the ages 8 through 16 years. Results All of the subjects had greater external rotation at 0° and 90° of abduction, decreased internal rotation at 90° of abduction, and greater retroversion of the humerus in their dominant compared with nondominant shoulders. A significant difference was found between dominant and nondominant external rotation at 0° and 90° of abduction, internal rotation at 90° of abduction, and retroversion of the humerus. In the dominant arm, there was a significant correlation between retroversion of the humerus and external rotation at 0° and 90° of abduction. There was also a significant correlation between the side-to-side difference in retroversion of the humerus compared with the side-to-side difference in external rotation at 90° of abduction. Conclusions Rotational changes in the throwing shoulder are due to bony as well as soft tissue adaptations.
Is Impingement the Cause of Jumper's Knee?
Authors: Schmid Marius R. , Hodler Juerg , Cathrein Philipp , Duewell Stefan , Jacob Hilaire A. C. , Romero José 
Published: July 2017

Background Chronic overload is considered the main cause of patellar tendinitis, but it has been postulated that impingement of the inferior patellar pole against the patellar tendon during knee flexion could be responsible. Hypothesis The role of the patellar pole in patellar tendinitis can be determined by dynamic magnetic resonance imaging. Study Design Case-control study. Methods We compared 19 knees with patellar tendinitis and 32 asymptomatic knees of age-matched subjects using an open-configuration magnetic resonance imaging system. Dynamic sagittal images were obtained from full extension to 100° of flexion with and without activation of the quadriceps muscle. The following measurements were made from the images: tendon-patella angle, anteroposterior diameter of the tendon, signal difference-to-noise ratio, the shape of the inferior patellar pole, and the location of the patellar tendon insertion. Results The tendon-patella angle was not significantly different between groups at any flexion angle, with or without quadriceps muscle activation. The insertion site of the patellar tendon differed significantly but not the shape of the inferior pole of the patella. The volume and the signal difference-to-noise ratio of zones of increased intratendinous signal as well as the anteroposterior diameter of the proximal patellar tendon were increased in symptomatic knees. Conclusions The relationship between the patella and the patellar tendon was identical in both groups; therefore, chronic overload seems to be a major cause of patellar tendinitis.
Shock Wave Therapy for Patients with Lateral Epicondylitis of the Elbow
Authors: Wang Ching-Jen , Chen Han-Shiang 
Published: July 2017

Background The results of both nonoperative and surgical treatments for lateral epicondylitis of the elbow have been inconsistent. Shock wave therapy has been shown to have a favorable short-term effect in treating this condition. Hypothesis Shock wave therapy is an effective treatment for patients with lateral epicondylitis of the elbow and long-term results will be as favorable as short-term ones. Study Design Case series. Methods The effect of shock wave therapy was investigated in 57 patients with lateral epicondylitis of the elbow. Forty-three patients (24 men and 19 women with an average age of 46 years) with 1 to 2 years of follow-up were included in this study. In addition, six patients were treated with a sham procedure as a control group. Each patient was treated with 1000 impulses of shock wave therapy at 14 kV to the affected elbow. A 100-point scoring system was used for evaluating pain, function, strength, and elbow range of motion. Results Twenty-seven elbows (61.4%) were free of complaints, 13 (29.5%) were significantly better, 3 (6.8%) were slightly better, and 1 (2.3%) was unchanged. In the control group, the results were unchanged in all six patients. There were no device-related problems and no systemic or local complications. Conclusions Shock wave therapy is a safe and effective modality in the treatment of patients with lateral epicondylitis of the elbow.