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BACKGROUND Hyperoxemia (arterial oxygen tension >100 mm Hg) may occur in critically ill patients and have effects on mixed venous saturation (SvO2 ) and on Fick-based estimates of cardiac output (CO). We investigated the effect of hyperoxemia on SvO2 and on assessments of CO using the Fick equation. METHODS Yorkshire swine (n = 14) were anesthetized, intubated, and paralyzed for instrumentation. SvO2 (co-oximetry) and tissue oxygen tension (tPO2 , implantable electrodes) in brain and myocardium were measured during systematic manipulation of arterial oxygen tension (PaO2 ) using graded hyperoxia (fraction of inspired oxygen 0.21 → 0.8). Secondarily, oxygen- and carbon dioxide-based estimates of CO (FickO2 and FickCO2 , respectively) were compared with measurements from a flow probe placed on the aortic root. RESULTS Independent of changes in measured oxygen delivery, cerebral and myocardial tPO2 increased in proportion to PaO2 , as did SvO2 (P

Background Measurement of cerebral venous oxyhemoglobin saturation (ScvO 2 ) is considered a gold standard in assessing the adequacy of tissue oxygen delivery (DO 2 ) after the stage 1 palliation (S1P), with SvO 2 2 . Regional oxygenation index (rSO 2 ) based on near-infrared resonance spectroscopy (NIRS) frequently is used to screen for compromised DO 2 , although its sensitivity to detect severe abnormalities in SvO 2 is uncertain. Methods ScvO 2 was measured by co-oximetry from the internal jugular vein as clinically indicated in 73 neonates after S1P. These values were compared with cerebral rSO 2 (FORE-SIGHT; CASMED) via mixed effects model linear regression, Bland-Altman analysis, and sensitivity analysis. Because NIRS devices measure a composite of arterial and venous blood, we calculated an rSO 2 -based ScvO 2 designed to remove arterial contamination from the rSO 2 signal: rSO 2 -based ScvO 2 = (rSO 2 − arterial oxygen saturation × 0.3)/0.7. Results Among 520 time-matched pairs of ScvO 2 and cerebral rSO 2 , the slope of the relationship between rSO 2 and ScvO 2 (after we adjusted for effects of hemoglobin) was 0.37 ± 0.04 with only modest correlation (r 2 = 0.39), and mean bias of +8.26. When ScvO 2 was 2 was 2 in the same range is >99%. Correction of rSO 2 for arterial contamination significantly decreased mean bias (+3.03) and improved the sensitivity of rSO 2 to detect ScvO 2 2 2 2 Conclusions Cerebral rSO 2 in isolation should not be used to detect low ScvO 2 , because its sensitivity is low, although correction of rSO 2 for arterial contamination may improve sensitivity. Cerebral rSO 2 of 50 or greater should not be considered reassuring, though values below 30 are specific for low ScvO 2 .

Visual Abstract, Highlights • Inhaled hydrogen gas has been shown to temper the sequelae of ischemic insults. Its application in cardiopulmonary bypass has not been investigated. • Neonatal swine were cannulated to cardiopulmonary bypass and exposed to prolonged circulatory arrest (75 min at 25°C). Swine were randomized to treatment with or without inhaled 2.4% hydrogen gas mixtures for 24 h during and following ischemic injury. Hydrogen-treated swine exhibited significantly less severe brain injury than controls, as quantified by clinical examination, serology, magnetic resonance-graded volume of injury, and histopathology. Hydrogen treatment also decreased renal injury. • The administration of inhaled 2.4% hydrogen gas mixtures through a standard ventilator and anesthesia machine were safe, even in the setting of electrocautery., Summary This study used a swine model of mildly hypothermic prolonged circulatory arrest and found that the addition of 2.4% inhaled hydrogen gas to inspiratory gases during and after the ischemic insult significantly decreased neurologic and renal injury compared with controls. With proper precautions, inhalational hydrogen may be administered safely through conventional ventilators and may represent a complementary therapy that can be easily incorporated into current workflows. In the future, inhaled hydrogen may diminish the sequelae of ischemia that occurs in congenital heart surgery, cardiac arrest, extracorporeal life-support events, acute myocardial infarction, stroke, and organ transplantation.

The Lancet Commission on Education of Health Professionals for the 21(st) Century calls for enhancing health education for the needs and challenges of the 21st century to improve health status globally. To complement the Lancet report, this article makes recommendations for including core global health competencies in the education of health care professionals and specific groups of the public who are relevant to oral health in a global context in order to tackle the burden of oral diseases. Experts from various professional backgrounds developed global oral health competencies for four target groups: Group 1 was defined as dental students, residents/trainee specialists (or equivalent), and dentists; Group 2 was community health workers, dental hygienists, and dental therapists (or the equivalent); Group 3 was health professionals such as physicians, physician assistants, nurses, nurse practitioners, and pharmacists; and Group 4 was non-health professionals in the public arena such as parents, teachers, decision makers, key opinion leaders, and health and consumer advocates. Key competencies for members of each of the four target groups are presented in a matrix. The suggested competency matrix shows that many other health professions and groups in society have potentially crucial roles in the prevention, control, and management of oral diseases globally. Workforce models including a wider range of professionals working together as a team will be needed to tackle the burden of oral diseases in an integrated way in the broader context of non-communicable diseases. Further discussion and research should be conducted to validate or improve the competencies proposed here with regard to their relevance, appropriateness, and completeness.

Assessing the adequacy of oxygen delivery to tissues is vital, particularly in the fields of intensive care medicine and surgery. As oxygen delivery to a cell becomes deficient, changes in mitochondrial redox state precede changes in cellular function. We describe a technique for the continuous monitoring of the mitochondrial redox state on the epicardial surface using resonance Raman spectroscopy. We quantify the reduced fraction of specific electron transport chain cytochromes, a metric we name the resonance Raman reduced mitochondrial ratio (3RMR). As oxygen deficiency worsens, heme moieties within the electron transport chain become progressively more reduced, leading to an increase in 3RMR. Myocardial 3RMR increased from baseline values of 18.1 ± 5.9 to 44.0 ± 16.9% (P = 0.0039) after inferior vena cava occlusion in rodents (n = 8). To demonstrate the diagnostic power of this measurement, 3RMR was continuously measured in rodents (n = 31) ventilated with 5 to 8% inspired oxygen for 30 min. A 3RMR value exceeding 40% at 10 min predicted subsequent cardiac arrest with 95% sensitivity and 100% specificity [area under the curve (AUC), 0.98], outperforming all current measures, including contractility (AUC, 0.51) and ejection fraction (AUC, 0.39). 3RMR correlated with indices of intracellular redox state and energy production. This technique may permit the real-time identification of critical defects in organ-specific oxygen delivery.

A continuous supply of oxygen to tissues is vital to life and interruptions in its delivery are poorly tolerated. The treatment of low-blood oxygen tensions requires restoration of functional airways and lungs. Unfortunately, severe oxygen deprivation carries a high mortality rate and can make otherwise-survivable illnesses unsurvivable. Thus, an effective and rapid treatment for hypoxemia would be revolutionary. The i.v. injection of oxygen bubbles has recently emerged as a potential strategy to rapidly raise arterial oxygen tensions. In this report, we describe the fabrication of a polymer-based intravascular oxygen delivery agent. Polymer hollow microparticles (PHMs) are thin-walled, hollow polymer microcapsules with tunable nanoporous shells. We show that PHMs are easily charged with oxygen gas and that they release their oxygen payload only when exposed to desaturated blood. We demonstrate that oxygen release from PHMs is diffusion-controlled, that they deliver approximately five times more oxygen gas than human red blood cells (per gram), and that they are safe and effective when injected in vivo. Finally, we show that PHMs can be stored at room temperature under dry ambient conditions for at least 2 mo without any effect on particle size distribution or gas carrying capacity.

From 2008 to 2011, the School of Dentistry at Muhimbili University of Health and Allied Sciences in Tanzania revised and then initiated implementation of a curriculum to improve the educational process for, and competence of, its graduates. As an increasing body of research demonstrates the detrimental effects of oral diseases on health and the interrelationships between oral and systemic diseases (including HIV and diabetes), the importance of dentistry education grows. We describe the population oral health problems in Tanzania, the need to enhance the dental workforce, and the process of curricular reform to meet these needs. This reform included transition to a competency-based curriculum featuring teaching methods that will enhance the effectiveness of the education and performance of graduates in traditional and new roles. We conclude with lessons for Tanzania and for health professions educational institutions elsewhere, as well as for public health-care planners concerned about linking health professions education to improving population health in resource-poor countries.

The challenges, problems, and solutions for developing a more streamlined and integrated curriculum at the University of California, San Francisco, School of Dentistry (UCSF) centered on thematic streams are presented. The central feature of the approach was that the curriculum reform efforts were initiated, developed, and implemented for the 2004-05 academic year primarily as a grassroots faculty effort with support by the administration. In addition, the issues in obtaining the consensus support of the faculty, students, and administration in order to proceed to implementation are discussed. Under the direction of a newly created position of assistant dean of curricular affairs and a faculty curriculum oversight group initiated in 2002, curriculum hours were adjusted to thirty-two hours per week. Departments conformed to this schedule, resulting in reductions in all areas of the curriculum, except clinical instruction, in order to provide time for independent study and electives. A new two-week introduction to the curriculum and an online course support system were also instituted. The new courses were generally well reviewed by students and faculty. Formal course evaluations and focus groups provided specific indications of needed adjustments. National Board scores were monitored and found to be unchanged from past experience. Curriculum change at UCSF required many changes in faculty behavior, including interdepartmental collaboration and efforts to improve teaching. Although many issues were anticipated and addressed in this multiyear reform process, careful faculty and administrative oversight continues to be required to maintain this structure. Continuing challenges include better integration of course materials and incorporating more learner-centered teaching strategies into the curriculum.

The Lancet Commission on Education of Health Professionals for the 21(st) Century calls for enhancing health education for the needs and challenges of the 21st century to improve health status globally. To complement the Lancet report, this article makes recommendations for including core global health competencies in the education of health care professionals and specific groups of the public who are relevant to oral health in a global context in order to tackle the burden of oral diseases. Experts from various professional backgrounds developed global oral health competencies for four target groups: Group 1 was defined as dental students, residents/trainee specialists (or equivalent), and dentists; Group 2 was community health workers, dental hygienists, and dental therapists (or the equivalent); Group 3 was health professionals such as physicians, physician assistants, nurses, nurse practitioners, and pharmacists; and Group 4 was non-health professionals in the public arena such as parents, teachers, decision makers, key opinion leaders, and health and consumer advocates. Key competencies for members of each of the four target groups are presented in a matrix. The suggested competency matrix shows that many other health professions and groups in society have potentially crucial roles in the prevention, control, and management of oral diseases globally. Workforce models including a wider range of professionals working together as a team will be needed to tackle the burden of oral diseases in an integrated way in the broader context of non-communicable diseases. Further discussion and research should be conducted to validate or improve the competencies proposed here with regard to their relevance, appropriateness, and completeness.

Objective: This study compared the efficacy of transmucosal anaesthetic patches containing lidocaine (46.1 mg/2 cm2) to placebo for local anaesthesia during quadrant scaling and root planing using periodontal clinical indices and patient perception of pain. Material and Methods: Forty healthy adults with moderate periodontal disease and moderate subgingival calculus were scaled at weekly intervals, two quadrants randomized to treatment patches and two quadrants randomized to placebo patches. Bleeding, probing depths and attachment levels were evaluated prior to treatment and 1 month after quadrant scaling was completed. Subjects completed 100 mm visual analogue pain scales 15 min. after patch placement and at the end of treatment, and were asked for verbal assessment of perceived pain. Results: Subjects' verbal ratings demonstrated consistently greater pain relief with active patches than placebo (p

Background The authors examined the attitudes and behaviors of a national sample of dentists regarding domestic violence and the barriers dentists face in intervening to help victims. Methods The authors surveyed a national random sample of 321 dentists by mail from November 1997 to March 1998 about their attitudes and clinical practice behaviors related to domestic violence. Survey items were developed based on the domestic violence and health care literature. The authors used the Total Design Method to maximize the response rate and analyzed data to determine differences between dentists who had received domestic violence education and those who had not. Results Eighty-seven percent of responding dentists never screened for domestic violence; 18 percent never screened even when patients had visible signs of trauma on their heads or necks. Overall, respondents intervened only minimally to help patients whom they had identified as victims. Respondents reported that the major barriers to screening were the presence of a partner or children (77 percent), lack of training (68 percent), concern about offending patients (66 percent) and their own embarrassment about bringing up the topic of abuse (51 percent). Respondents who had received domestic violence education were significantly more likely to screen for domestic violence and to intervene. Conclusions Dentists face many barriers to identifying and helping patients who are abuse victims, yet these data suggest that education about domestic violence could help them overcome some of these barriers. Clinical Implications We suggest that dentists follow the AVDR model when approaching abused patients in their practice: Ask about abuse, provide Validating messages, Document presenting signs and Refer victims to domestic violence specialists.

This study quantified changes in blood flow following tooth brushing, using laser Doppler flowmetry (LDF). Twenty subjects had polysiloxane stents fabricated with openings to permit placement of the LDF probe on the mesial papillae of 6 teeth. Probing depth, plaque index, and gingival index were recorded and subjects instructed in brushing. LDF initially recorded a 30 second baseline blood flow. The stent was removed and subjects brushed the site for either 3 or 10 seconds. The stent was repositioned and recordings again taken, followed by a control reading. The process was repeated 4 weeks later. Correlations between baseline and control readings were 0.585 (P0.001) at the first visit, and 0.654 (P0.001) at the return visit. The mean control blood flow was 156.4 perfusion units. The 3 and 10 second brushing increased the mean value 22.6 units and 21.2 units respectively (both P0.001). Tooth brushing for both 3 and 10 seconds significantly increased gingival blood flow in the papillary gingiva of healthy individuals.

Objectives This study determined demographic characteristics, satisfaction with care, and likelihood of follow-up dentist visits for patients seen in office-based, independent, dental hygienist practices. Methods New patients were surveyed after their initial visits to independent hygienist practices to assess their demographic characteristics and satisfaction with care at both the beginning of practice operations and 18 months after the start of these practices. Follow-up surveys were sent to patients 12 and 24 months after their initial visits to the independently practicing dental hygienists to determine if patients had visited a dentist. Results Most respondents were white, female, had attended some college, and reported high family incomes. Ninety-eight percent of respondents were satisfied with their dental hygiene care. Follow-up questionnaires revealed that over 80 percent of respondents visited the dentist within 12 months of receiving dental hygiene care in independent settings. This level of follow-up care with dentists was found both for respondents who reported having a regular dentist at their initial visits with the hygienists and for those who reported not having a regular dentist. Conclusions Independent practice by dental hygienists provided access to dental hygiene care and encouraged visits to the dentist.

Background and objectives Lasers are now used for intraoral, soft tissue procedures. The effects of Nd:YAG probes on cutting efficiency and temperature rise were evaluated in vitro. Study design/materials and methods Three hundred twenty-micron 400-microns, 500-microns, and 600-microns probes were used to ablate bovine gingiva, mucosa, and tongue at various power and frequency settings. Thermocouples positioned under the subjacent cortical bone measured temperature rise. Tissue samples were evaluated histologically. Results Mean pooled temperature rise was 1 degree C at 3 W and 1.4 degrees C at 5 W. Excision width ranged from 0..63 mm to 0.79 mm at tested settings, cutting depths from 0.19 mm to 0.49 mm, lateral and deep coagulation from 0.27 mm to 0.62 mm. Conclusion Temperature rise in bone was related to increased power. Cutting efficiency of laser probes was not significantly improved by increased power. Probes of 320 to 500 microns provided efficient cutting at 3 W and 5 W, thus reducing the potential for unacceptable temperature rise in bone.

The purpose of this clinical trial was to compare the efficacy of a new flossing aid (Flosser) with finger flossing on preventing plaque and gingival inflammation. 35 adults who did not use dental floss routinely were assigned randomly to one of 2 treatment groups (Flosser or finger flossing) in a 2-period, single-blind crossover study. After prophylaxis, subjects were instructed to use the flossing aid or finger floss 1 x per day and to continue brushing for 30 days. Gingival inflammation (GI & BPI) and plaque (PI) were assessed prior to the prophylaxis and at 30 days. After a 30 day "washout" period, subjects were again reassessed for gingival inflammation and plaque, given a prophylaxis, assigned the opposite treatment (2nd treatment period) that they received the first treatment period, and assessed (GI, BPI & PI) after 30 days. Comparing the mean difference of the 30-day buccal interproximal scores between the treatment groups (flossing aid scores minus finger flossing scores) showed that the mean differences with 95% CI were: -0.013 +/- 0.067 [GI], -0.017 +/- 0.044 [BP] and 0.019 +/- 0.014 [PI]. No statistically significant differences from zero (0.05 alpha) were observed using the t-test. There was a high level of compliance (90%) with the prescribed regiment, and subjects preferred (56%) the flossing aid slightly over finger flossing. Even though there were no statistically or clinically significant differences in gingivitis and plaque scores between the 2 flossing groups, the positive inclination for the flossing aid makes it a desirable addition to the armamentarium of preventive dentistry.

Background The authors conducted a study to compare administration of local anesthetic using a computer-controlled delivery device with an aspirating syringe for therapeutic scaling and root planing. The anterior middle superior alveolar, or AMSA, injection was compared with other maxillary injections. Methods Twenty healthy adults with moderate periodontal disease participated in this single-blind crossover study. Subjects were evaluated by a trained examiner and were treated by experienced dental hygienists. Subjects provided written and verbal pain ratings via a visual analog scale, or VAS, and a verbal rating scale, or VRS. AMSA injections were compared with syringe-delivered injections—greater palatine, or GP, and nasopalatine, or NP, blocks, and anterior superior alveolar and middle superior alveolar injections—in maxillary quadrants. Bleeding and changes in attachment were evaluated after one month. Results VAS and VRS scores for AMSA were significantly lower for computer-controlled delivery when compared with NP injections and combined maxillary injections (VAS scores) and with GP and combined maxillary injections (VRS scores). Mean injection times were similar for both groups. Mean gains in attachment were equal, 0.19 millimeters for quadrants anesthetized using computer-controlled injections and 0.22 mm for syringe injections. Conclusions Subjects reported having less pain with GP and NP injections delivered using the computer-controlled device, and total injection time was similar to that required for syringe injections. Both techniques provided adequate anesthesia for therapeutic scaling and root planing. Clinical Implications The two anesthetic delivery techniques were therapeutically equivalent for mandibular injections, and the AMSA injection has clinically significant advantages for maxillary injections.

Objective The purpose of this study was to assess aspects of the quality of care provided by dental hygienists in a California demonstration project in which hygienists treated patients independent of dentists' supervision. Methods The structure and process of care were evaluated in nine independent practices using site visits and reviews of 25 records at each practice. The findings were compared to evaluations of six general dentist practices reviewed for a government agency and insurance company during the same time period. Patient satisfaction was assessed by a questionnaire. Results The structural aspects of the unsupervised hygienist practices were generally acceptable and surpassed the dentist practices in most areas, including infection control. For process, the hygienist practices had high percentages of acceptable care and were significantly better than the dentist practices in several areas, including follow-up to medical findings, updating the medical history at recall, and documenting the evaluation of the periodontal status and soft tissues. Ninety-eight percent of patients expressed satisfaction with their care in hygienist practices. Conclusion Under the circumstances of the demonstration project and the methods used to assess the quality of care, the study showed that independent dental hygienist practice did not increase the risk to the health and safety of the public.

We compared the accuracy, consistency, time, comfort, and cost of probing with a conventional hand probe (CP) with 3-mm banded markings, a manual pressure-regulated probe (MP), and two electronic probes (IP and FP). Twenty (20) examiners used all four probes on a test block to determine accuracy; measurements compared favorably to the reference block. Two calibrated examiners probed the Ramfjord teeth of 10 periodontal patients on maintenance regimens, six sites per tooth (n = 708), with all four probes; measurements were repeated after one week. Wilcoxon signed-rank test showed the CP measured more deeply (P < 0.0001) than MP, FP, and IP with mean differences of 0.40, 0.67, and 0.58 respectively. MP measured more deeply (P < 0.001) than FP and IP, with mean differences of 0.27 and 0.18 mm. There was no difference between FP and IP. Time (min:sec) required by one examiner to perform full mouth probing on six subjects (minimum of 26 teeth each) was CP = 3:59; MP = 4:18; FP = 6:16; and IP = 7:23. Subjects rated FP and IP as slightly more uncomfortable than CP or MP. Cost per 1,000 uses was computed based on available data. The IP and FP took longer to perform and cost more per procedure than did the CP and MP. Spearman rank-order correlation revealed that only probe depths measured by CP and MP were well correlated (rs = 0.67). Although some statistically significant differences were found between probes, no differences were considered to be of clinical significance when probing periodontally healthy or maintenance patients.(ABSTRACT TRUNCATED AT 250 WORDS)

The presence of periodontitis in 307 black, Hispanic, and Asian students age 12 to 15 years was evaluated by calibrated examiners in a Los Angeles inner city junior high school. The periodontal status of maxillary and mandibular incisors and permanent first molars was evaluated using the Plaque Index, probing depth, attachment loss, bleeding on probing, tooth mobility, presence of calculus, and caries. Thirty-nine (12.7%) of 307 students had 5 mm or deeper probing depths and associated attachment loss of at least 2 mm and were considered to have periodontitis (PD). The PD group had significantly more bleeding, calculus, and missing teeth than the non-PD group, but both groups had moderate to severe plaque accumulation. The distribution and severity of disease increased with age. Deeper probing depths were associated with the molar teeth and six (15.4%) of the 39 subjects in the PD group had furcation involvement. Clinical screening alone was not sufficient to determine if the periodontitis seen was localized juvenile periodontitis; however, the program detected a high occurrence of periodontitis in this population group.