Evaluation of a Custom Made Pulse Oximeter Dental Probe in Detecting Pulp Vitality: A Clinical study

The aim of the study was to design and develop a probe that adapts to the contour of the permanent central incisor and to evaluate its efficiency in detecting the vascular integrity of human teeth and to compare it with the electric pulp tester. The newly designed probe was able to adapt to the contour of the central incisor and was stable in its position without the operator holding it. It was used to evaluate pulp vascularity on 185 subjects of which 175 subjects were in the study group and 10 in the control group. The result obtained was also compared with the results of the electric pulp tester. The conclusions derived from the results of this study are: 1. The newly developed probe and the NONIN hand held pulse oximeter were able to detect the blood flow in the tooth of the study group and recorded values which were lower than the finger readings. 2. Oxygen saturation values of the tooth compared to the Oxygen saturation values of the finger was statistically significant with a p value of 0.016. 3. Oxygen saturation values of the tooth compared to the electric pulp tester values was statistically significant was with a p value of 0.045. Consistent pulse oximetry readings detected by the newly developed probe in this study have confirmed the pulsatile blood flow and its oxygen saturation in tooth. Moreover this study shows that pulse oximetry is an effective, objective and a non- invasive method for the clinician to determine pulp vitality of the permanent incisors. It can also be used in primary and immature permanent teeth where patient co -operation and incomplete pulp innervations reduces the effectiveness and reliability of thermal and electric pulp testers. Further study in the probe design which could be used universally for all teeth is in progress and its success will be a boon for the diagnosis of pulp vitality

Comparative outcomes between HIV positive and negative endodontic patients

Purpose: To compare the presenting symptoms and the outcomes of root canal therapy between HIV positive and HIV negative endodontic patients over a 6-12 month period. Methods: Fifty-nine HIV negative and 46 HIV positive patients presented for endodontic treatment. Signs and symptoms were noted and compared for both groups of patients, together with demographic data and CD4 counts for the HIV positive patients. Endodontic procedures were evaluated after an 18-month period. Endodontic treatment was assessed using clinical factors (palpation, percussion, sensitivity to hot and cold, swellings, excessive bleeding), and radiographic factors (periapical radiolucency, root resorption, periodontal ligament space). Results: There was no statistically significant difference in the preoperative presenting symptoms of endodontic infections/conditions between HIV positive and HIV negative patients. The prevalence of radiographic caries in the presenting teeth was only 24% in the HIV positive patients compared with 95% in the HIV negative patients. For the HIV positive patients, the treatment time required to resolution of the endodontic infection was nearly twice (113 minutes) that of the HIV negative patients (52 minutes). Amongst the HIV positive patients still experiencing symptoms at 18 months, pain was more severe in those patients with lower CD4 counts (significance at the 90% level of confidence). Conclusion: Within the limitations of this study the following conclusions emerge: 1. Although the success rate was lower over the period of this study in HIV positive patients, the rate is sufficiently high to warrant treatment. 2. Patients who are HIV positive may present with more severe symptoms and during treatment more bleeding may be expected. 3. In keeping with best practice for immuno-compromised patients, it would be advantageous to put HIV positive patients on antibiotic cover during treatment. 4. The process of anachoresis may explain the high incidence of endodontic infections in teeth with no history of trauma or caries in the HIV positive group

Space benefits: The secondary application of aerospace technology in other sectors of the economy

Over 580 examples of the beneficial use of NASA aerospace technology by public and private organizations are described to demonstrate the effects of mission-oriented programs on technological progress in the United States. General observations regarding technology transfer activity are presented. Benefit cases are listed in 20 categories along with pertinent information such as communication link with NASA; the DRI transfer example file number and individual case numbers associated with the technology and examples used; and the date of the latest contract with user organizations. Subject, organization, geographic, and field center indexes are included

Automatic stimulus breaker for electric dental pulp tester using pain response

The pulp test provides a means of examining the vitality of dental pulp using physical or chemical stimulation. During electrical pulp testing, an electrical current stimulates the intradental nerve, which may be painful and stressful to patients. The study involved measurement of the electromyogram (EMG) from the anterior belly of the digastric muscle, finger movement and voice response during electrical pulp testing. The excessive stimulus time from the onset time of response (EMG, voice and finger movement) to the end of the stimulation was obtained. The results indicated that the responses occurred in the order: EMG, finger and voice. Based on these results, an automatic stimulus shut-off circuit was developed using the above-mentioned responses to stimulus during electric pulp testing. Excessive stimulus time was reduced by prompt switching-off of the pulp tester output, 64 ms on average after the first detected response (EMG). Consequently, excessive stimulus times were reduced by 284 and 152 ms on average for the subject and examiner disconnection, respectively, using the developed automatic shut-off circuit. Therefore it was possible to minimise pain and stress by reducing excessive pulp stimulation.restrictio

Chapter 34 - Biocompatibility of nanocellulose: Emerging biomedical applications

Nanocellulose already proved to be a highly relevant material for biomedical applications, ensued by its outstanding mechanical properties and, more importantly, its biocompatibility. Nevertheless, despite their previous intensive research, a notable number of emerging applications are still being developed. Interestingly, this drive is not solely based on the nanocellulose features, but also heavily dependent on sustainability. The three core nanocelluloses encompass cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs), and bacterial nanocellulose (BNC). All these different types of nanocellulose display highly interesting biomedical properties per se, after modification and when used in composite formulations. Novel applications that use nanocellulose includewell-known areas, namely, wound dressings, implants, indwelling medical devices, scaffolds, and novel printed scaffolds. Their cytotoxicity and biocompatibility using recent methodologies are thoroughly analyzed to reinforce their near future applicability. By analyzing the pristine core nanocellulose, none display cytotoxicity. However, CNF has the highest potential to fail long-term biocompatibility since it tends to trigger inflammation. On the other hand, neverdried BNC displays a remarkable biocompatibility. Despite this, all nanocelluloses clearly represent a flag bearer of future superior biomaterials, being elite materials in the urgent replacement of our petrochemical dependence

The Plastics Collection Reference Packet

This reference packet is an informational tool to support further research into the history of plastics—whether interested in companies, individuals within the plastics industry\u27s history, historical plastics materials, essays, and more. All content featured within this packet was previously published on the former plastics.syr.edu website as part of a Syracuse University Libraries and Special Collections Research Center (SCRC) partnership established in 2007 with the Plastics Pioneers Association (PPA)—an association of plastics industry professionals interested in preserving the plastics industry\u27s past