Relationships among temperament, acute and chronic cortisol and testosterone concentrations, and breeding soundness during performance testing of Angus bulls.

The aim of this study was to examine relationships among temperament, endocrinology, and reproductive parameters of bulls enrolled in an 84-day performance test. Angus bulls (n = 60) were housed in six pens grouped by age and weight. Pen scores (PS; 1 = docile to 5 = very aggressive) were assigned on Days -1, 27, 55, and 83 of the performance test. On the following day, blood and hair samples were collected, and body weight (BW) and exit velocity (EV) were recorded. Bulls were split into two categories based on; Day -1 PS (PScalm = PS 1 or 2; PSexcitable = PS 3 or 4) and Day 0 EV (EVcalm = slowest 20 bulls; EVexcitable = fastest 20 bulls). Cortisol and testosterone concentrations in serum and hair did not differ (P > 0.10) between PS or EV temperament categories. Sampling day differences (P < 0.01) occurred for serum testosterone, hair cortisol, and hair testosterone concentration; however, serum cortisol concentration did not differ (P > 0.10) over the sampling days. Serum testosterone concentration increased (P < 0.01) from Day 0 to 28, decreased from Day 28 to 56, but Day 84 did not differ from Day 0, 28, or 56. Hair cortisol concentration was greatest (P < 0.01) on Day 0, decreased from Day 28 to 56 but did not differ from Day 56 to 84. Hair testosterone concentration was greatest (P < 0.01) on Day 0 and remained constant from Day 28 to 84. Bulls categorized as PScalm had a greater (P < 0.01) percentage of normal sperm and secondary defects (P < 0.01) when compared with PSexcitable bulls. However, EVcalm bulls had fewer (P < 0.01) primary defects but more (P < 0.01) secondary defects than EVexcitable bulls. In conclusion, bulls exhibited physiological evidence of acclimation during the test as indicated by a reduction in hair cortisol concentration. In addition, the ability of the bulls to acclimate while residing at the testing center may have contributed to little differences observed during the breeding soundness examination portion of the performance test.

Relationships among temperament, behavior, and growth during performance testing of bulls.

Excitable cattle are dangerous to personnel and have reduced individual performance. The aim of this study was to 1) identify objective criteria for evaluating bull temperament and 2) examine relationships among temperament, behavior, and performance of bulls during an 84-d performance test. Angus bulls ( = 60) were reared in 6 pens based on BW and age. Pen scores (PS; 1 = docile and 5 = very aggressive) were assigned on d -1, 27, 55, and 83. Exit velocity (EV), BW, time to exit the chute, and order through the chute were recorded on d 0, 28, 56, and 84. The ADG was calculated for the 84-d test period, and ultrasound data and frame score calculations were recorded on d 84. Dataloggers measured steps taken, lying time, number of lying bouts, and lying bout duration of bulls ( = 27; 3 pens) from d 3 to 28 and d 59 to 84. Bulls with a d -1 PS of 1 or 2 were categorized as calm (PScalm; = 40), whereas bulls with a PS of 3 or 4 were categorized as excitable (PSexcitable; = 20). Bulls were separated into 2 groups based on the bottom 20 EV (EVcalm) and top 20 EV (EVexcitable) on d 0. Mixed model ANOVA (SAS 9.3) was used to compare groups for the two temperament assessment methods, behavior, and growth performance. Mean EV decreased ( < 0.05) by d 84. Total lying time from d 3 to 28 was greater ( < 0.05) for PScalm bulls when compared with PSexcitable bulls. However, total lying time from d 59 to 84 was greater ( < 0.05) for EVexcitable bulls when compared with EVcalm bulls. Regardless of initial contemporary group assignment, all bulls exited the chute slower ( < 0.001) on d 84 than on d 0. The PSexcitable bulls had greater ( < 0.01) frame scores and greater ADG than PScalm bulls. The PSexcitable bulls had more ( < 0.01) backfat than PScalm bulls. However, ribeye area was smaller ( < 0.01) in EVexcitable bulls than EVcalm bulls. Based on these results, bulls appeared to have habituated over the testing period. Additionally, the potential lack of innate temperament variation may have attributed to the little difference seen among the behavioral and performance data. Therefore, temperament should be reassessed within a novel environment with new handlers to differentiate between the bull's true temperament and its ability to habituate.

Quantifying the diffused benefit from water fluoridation in the United States.

OBJECTIVE: To estimate the total contribution of water fluoridation to caries reduction by including the benefit from the diffusion of fluoride from fluoridated communities to surrounding nonfluoridated communities via the export of bottled beverages and processed foods. METHODS: We analyzed data from the 1986-87 NIDR Children's Survey for 18,507 school children aged 6-17 years who had at least one permanent tooth and for whom a complete fluoride exposure history could be created. To measure water fluoridation exposure, we generated continuous and categorical exposure variables. Years of fluoridation exposure (YFE-continuous) measured the number of years the child lived at residences receiving fluoridated water. Lifetime fluoridation exposure (LFE-categorical) was high if the child lived at residences receiving fluoridated water more than 50% of his life and low, otherwise. We summed the proportion of state population receiving fluoridated water times the number of years the child had lived in each state and then divided this value by the child's age to measure diffusion exposure (DE). We grouped DE into three levels: low (DE<=0.25), medium (0.25=0.55). For each level of DE, we compared the age-adjusted mean DMFS for high and low LFE. In addition we used linear regression to measure the association between DMFS and YFE while controlling for DE, age, exposures to other fluoride sources, and sociodemographic variables. Reported results are significant at P<0.05. RESULTS: Comparison of mean DMFS scores found that the direct benefit of water fluoridation (DMFS(LFE=low) - DMFS(LFE=high)) was 1.44 surfaces among low DE children and 0 among high DE children. The diffused benefit (DMFS(LFE=low, DE=low) - DMFS(LFE=low, DE=high)) was 1.23 surfaces. The regression results were similar and indicated that the direct benefit would be 1.44 fewer DMFS for low DE children and the indirect benefit would be 1.09 fewer DMFS for high DE children. CONCLUSION: Failure to account for the diffusion effect may result in an underestimation of the total benefit of water fluoridation, especially in high diffusion exposure regions.

Fluoride varnishes. A review of their clinical use, cariostatic mechanism, efficacy and safety.

BACKGROUND: This is a review of the clinical use, cariostatic mechanism, efficacy, safety and toxicity of fluoride varnishes. TYPES OF STUDIES REVIEWED: The authors reviewed and summarized in vitro, in vivo and in situ studies; clinical trials; demonstration programs; position papers; and editorials published in English in the biomedical literature since 1966. RESULTS: Extensive laboratory research and clinical trials conducted in Europe and elsewhere show that fluoride varnishes are as efficacious as other caries-preventive agents. Fluoride varnishes are widely used in European caries-preventive programs. The U.S. Food and Drug Administration has cleared these products only as medical devices to be used as cavity liners and for the treatment of hypersensitive teeth. These products have not yet been cleared for marketing in the United States as caries-preventive agents. CLINICAL IMPLICATIONS: Three fluoride varnishes are currently available in the United States. Semiannual applications are the most proven treatment regimen. Varnishes are safe and easy to apply and set in contact with intraoral moisture.

Occupational blood exposure and HIV infection among oral and maxillofacial surgeons.

OBJECTIVE: The purpose of this study was to examine occupational blood exposure and the seroprevalence of HIV infection among oral and maxillofacial surgeons. STUDY DESIGN: Three hundred twenty-one oral and maxillofacial surgeons attending an annual meeting voluntarily and anonymously participated in an HIV serosurvey and completed a questionnaire assessing practice and demographic factors. Statistical tests included the Wilcoxon rank-sum test and the chi-squared test. RESULTS: Eighty percent of those who completed the survey reported one or more blood-skin contacts within the previous month. The mean number of percutaneous injuries within the previous year was 2.36 +/- 0.2. Wire was most commonly associated with percutaneous injuries. Oral maxillofacial surgeons who reported three or more percutaneous injuries performed more fracture reductions than oral and maxillofacial surgeons reporting no percutaneous injuries (p < 0.01). No participant was HIV-positive; the upper limit of the 95% confidence interval was 1.15%. CONCLUSION: The findings suggest that the occupational risk for HIV infection in oral surgery is very low even though most oral and maxillofacial surgeons experienced blood contact. Associations of percutaneous injuries with fracture reductions and wire may assist in the development of new techniques and equipment to minimize blood exposures.

Occupational blood exposures in dentistry: a decade in review.

This review summarizes data from self-reported and observational studies describing the nature, frequency, and circumstances of occupational blood exposures among US dental workers between 1986 and 1995. These studies suggest that, among US dentists, percutaneous injuries have declined steadily over the 10-year period. Data also suggest that, in 1995, most dental workers (dentists, hygienists assistants, and oral surgeons) experienced approximately three injuries per year. Work practices (eg, using an instrument instead of fingers to retract tissue), safer instrumentation or design (eg, self-sheathing needles, changes in dental-unit design), and continued worker education may reduce occupational blood exposures in dentistry further.

Percutaneous injuries during oral and maxillofacial surgery procedures.

PURPOSE: This study estimated the frequency of percutaneous injuries (Pls) to dental health-care workers during oral and maxillofacial surgery and examined the circumstances surrounding the incidents. MATERIAL AND METHODS: A self-reported, prospective study was conducted to document Pls incurred during oral and maxillofacial surgery performed on outpatients and inpatients over 1-month and 6-month periods, respectively. Among the study variables examined were the numbers of patients treated, number and types of procedures performed, duration of treatment, numbers and types of health care workers at risk, treatment setting, and number of injuries. RESULTS: Four injuries were recorded during 362 operating room procedures on 236 inpatients, for a rate of 1.1 Pls per 100 procedures (95% confidence interval: 0.3 to 2.8) and 1.7 Pls per 100 patients (95% confidence interval: 0.5 to 4.6). These four injuries occurred during 1,665 person-procedures (mean number of workers present at each procedure times the total number of procedures) for a rate of 0.24 Pls per 100 person-procedures (95% confidence interval: 0.1 to 1.0). Three injuries took place during fracture reductions; two were caused by surgical wire and the third by a needlepoint Bovie tip. One injury occurred during orthognathic surgery and involved a Woodson elevator. Residents recorded no injuries while treating 521 outpatients (0 Pls per 100 patients; 95% confidence interval: 0 to 0.6). CONCLUSION: The results support previous findings that Pls rarely occur during outpatients oral and maxillofacial surgery procedures. However, the findings suggest that operating room procedures for oral and maxillofacial surgery that use wire or involve fracture reduction may be associated with an increased risk of injury. Strategies such as using a cork or sponge to cap sharp wires or instruments, and protecting hands and fingers by double gloving, may be used to decrease the risk of Pl.

Hepatitis B vaccination and infection among U.S. dentists, 1983-1992 .

The hepatitis B vaccine became commercially available in 1982. Since then, health care workers, including dentists, have been encouraged to be vaccinated. This study examines the prevalence of hepatitis B vaccination and infection among U.S. dentists from 1983 to 1992.

Trends in state agency oral health and public health expenditures, 1984 through 1989.

This paper documents oral health and public health expenditures for fiscal years 1984, 1986, 1988, and 1989, as reported by state health agencies. During this period, reported national expenditures for public and oral health increased 68% and 46%, respectively; between successive fiscal years, fewer states (73%, 67%, 57%) reported increased oral health expenditures, while increasingly more states reported no categorical oral health expenditures. Block grant expenditures for oral health increased overall but decreased as a percentage of total oral health expenditures; 16 states reported no block grant expenditures for oral health in fiscal year 1989, perhaps reflecting either substantial state support, or marginal to nonexistent oral health programs in these states.

Percutaneous injuries in dentistry: an observational study.

The authors conducted an observational study of the frequency and circumstances of percutaneous injuries among dental residents. Their findings suggest that most percutaneous injuries sustained by these dental residents occurred extraorally and were associated with denture impression procedures. Some injuries may be preventable with changes in techniques or instrument design.

Trends and differentials in mortality from cancers of the oral cavity and pharynx in the United States, 1973-1987.

BACKGROUND: This analysis consisted of an examination of trends and differentials in mortality from cancers of the oral cavity and pharynx in the United States for a recent 15-year period. METHODS: The authors have used national cause-of-death data for the United States and intercensal population estimates to examine mortality from oral and pharyngeal cancers between 1973 and 1987 and to study differentials according to gender, race, and region of residence. RESULTS: The overall mortality rate from these cancers decreased by 19% during the 15-year period, with most of the decline occurring after 1979. Mortality was much higher for men than for women and for blacks than for whites throughout the interval. Despite the overall decline, mortality rates increased among blacks, especially among black men. Mortality was highest in the South Atlantic, New England, and Mid-Atlantic states and lowest in the Mountain states. CONCLUSIONS: The disparity between male and female mortality from oral and pharyngeal cancer stems mainly from differences in the likelihood of developing these cancers, whereas the differences between blacks and whites appears to arise more from differences in survival than in incidence. Different age patterns of mortality for blacks and whites exist, in which mortality among whites, but not among blacks, rises continuously with age. An unexplained finding was that mortality rates were reported to have fallen in recent years, whereas incidence and survival rates have reportedly remained almost unchanged. This apparent inconsistency may have resulted from declines in the incidence of oral and pharyngeal cancers that have been masked by improved detection.

Factors associated with hepatitis B vaccine response among dentists.

The objective of this study was to evaluate personal and immunization factors associated with serologic evidence of hepatitis B virus (HBV) vaccine response. A study was conducted using data from United States dentists participating from 1987 to 1991 in the Health Screening Program of the American Dental Association's annual session. This study included dentists (n = 507) who (1) received their most recent dose of HBV vaccine within the previous 10 months, (2) completed a core questionnaire, and (3) were tested for HBV markers (HBsAg, anti-HBs, and anti-HBc) and were found not to have evidence of past or present infection. Non-responders were defined as dentists testing negative for all three markers (n = 100). Responders were defined as dentists having serological evidence of anti-HBs alone (n = 407). Logistic regression models were used to assess the relationship of vaccine response to the variables sex, age, number of vaccine doses, site of vaccination, type of vaccine, and history of hepatitis. Vaccine response was most strongly associated with sex, age, and number of doses. Factors unrelated to vaccine response included type of vaccine and history of hepatitis. Adherence to the recommended number of doses and early vaccination are critical to adequate protection against hepatitis B infection of dentists, who are often exposed to blood and other body fluids.

The association between water fluoridation and hip fracture among white women and men aged 65 years and older. A national ecologic study.

For the past 45 years, there has been a great deal of debate regarding the health issues surrounding the fluoridation of public water supplies. In order to assess the association between fluoridation and hip fracture, we identified 129 counties across the United States considered to be exposed to public water fluoridation and 194 counties without exposure. Data from the Health Care Financing Administration and the Department of Veterans Affairs were used to calculate the incidence of hip fracture among white persons, aged 65 years or older, in fluoridated and nonfluoridated counties. There was a small statistically significant positive association between fracture rates and fluoridation. The relative risk (95% confidence interval) of fracture in fluoridated counties compared to nonfluoridated counties was 1.08 (1.06 to 1.10) for women and 1.17 (1.13 to 1.22) for men. As comparisons were made at the grouped level, it may be inappropriate at this time to draw inferences at the individual level. The relationship observed at the county level needs to be duplicated at the individual level with more precise measures of fluoride exposure.