An analysis of preventive dental visits by provider type, 1996

BACKGROUND

Understanding preventive dental visit utilization patterns facilitates planning of the dental health services delivery system. The authors examine these patterns by analyzing the receipt of preventive dental services in the United States by type of dental provider.

METHODS

The authors analyzed data from the 1996 Medical Expenditure Panel Survey (MEPS) for the U.S. community-based population. They developed national estimates for the population with preventive dental visits by provider type, including the population with a preventive dental visit and mean number of preventive dental visits per person for socioeconomic and demographic categories.

RESULTS

Respondents who are white, are older, are female, have dental insurance, are from higher income and education backgrounds, and reside in small metropolitan areas were more likely (P < .05) to receive preventive care from a dental hygienist than from a dentist.

CONCLUSION

MEPS data showed that people's socioeconomic background and other demographic factors were associated with having a preventive dental visit with a dentist or dental hygienist. These factors also influence the per-person number of preventive visits by type of dental practitioner. These elements must be considered when planning for future dental work force needs.

PRACTICE IMPLICATIONS

Estimating future dental work force needs through this analysis assists dentists in meeting patient demand and maximizing the productive output of all services rendered in their practices, including preventive services.

Myocardial tumor necrosis factor-alpha expression does not correlate with clinical indices of heart failure in patients on left ventricular assist device support

BACKGROUND

Mechanical unloading with a left ventricular assist device (LVAD) can improve clinical indices of heart failure and alter myocardial tumor necrosis factor-alpha (TNFalpha) expression, but a correlation between clinical and molecular indices has not been established.

METHODS

We enrolled 14 patients with end-stage heart failure treated with drugs and mechanical unloading in a protocol including the collection of myocardial tissue samples at LVAD implantation and explantation. Ten nonfailing donor hearts served as controls. TNFalpha expression was measured by quantitative reverse transcription polymerase chain reaction. Clinical indices of heart failure were retrospectively analyzed and correlated with myocardial TNFalpha expression.

RESULTS

Left ventricular end-diastolic dimension decreased (p < 0.01) and cardiac index (p < 0.001) increased with unloading. Abnormal values of serum sodium, creatinine, blood urea nitrogen, glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase, and albumin showed a trend toward normalization with mechanical unloading. TNFalpha expression was increased in 5 of 14 patients and decreased with mechanical unloading in 4 of them. Surprisingly, there was no correlation between mRNA levels of TNFalpha and any of the clinical indices studied.

CONCLUSIONS

Although clinical indices of heart failure improve and elevated levels of myocardial TNFalpha expression decrease with mechanical unloading, there is no correlation between the two. Thus, clinical and molecular indices of heart failure in LVAD-supported patients do not always correlate.

The ethics of placebo-controlled trials in developing countries to prevent mother-to-child transmission of HIV

Placebo-trials on HIV-infected pregnant women in developing countries like Thailand and Uganda have provoked recent controversy. Such experiments aim to find a treatment that will cut the rate of vertical transmission more efficiently than existing treatments like zidovudine. This scenario is first stated as generally as possible, before three ethical principles found in the Belmont Report, itself a sharpening of the Helsinki Declaration, are stated. These three principles are the Principle of Utility, the Principle of Autonomy and the Principle of Justice. These are taken as voices of moral imperative. But although each has intuitive appeal, it can be shown that there are possible scenarios in which they give conflicting prescriptions. To achieve consistency, one must be subordinate to the others. The voice of utility is taken as subordinate to those of justice and autonomy and it is shown that given plausible assumptions about the level of poverty and education in the developing country targeted, the experiment is ruled morally wrong in the name of both justice and autonomy. Moreover, it is argued that no justification can be found for the inclusion of a placebo group, when strictly defined. By contrast, a 'no-treatment' control arm might be justified, but only when the demands of autonomy are satisfied, demands that are more stringent than they might appear. A utilitarian defence of the experiment is examined, namely that the would-be participants are in a no-loss situation, and it is shown that this defence is seriously flawed. Finally, it is concluded that there is no justification for amending the Declaration of Helsinki.

Lack of immunity in university students before an outbreak of serogroup C meningococcal infection

Immunity to meningococci was determined in infected and uninfected students before and during an outbreak of serogroup C meningococcal infection at a university in the United Kingdom. No immunity against the outbreak strain was detected in serum taken from infected students prior to the outbreak or at the time of admission; bactericidal activity developed during convalescence. Carriage of all strains of serogroup C meningococci in asymptomatic students was low (0.9%), and no carriage of the outbreak strain could be detected. Immunity in the at-risk student population before the outbreak was low: 90% of students had no significant bactericidal activity against the outbreak strain. A low prevalence of carriage of the outbreak strain, together with a low prevalence of protective immunity within the student population, was associated with a high incidence of invasive disease in those who acquired the outbreak strain.

Root trunk dimensions of 5 different tooth types

The primary purpose of this study was to document mean, standard deviation, and range of root trunk dimensions of multirooted tooth types. A total of 412 extracted teeth were examined and classified as: maxillary first molars, maxillary second molars, maxillary first premolars, mandibular first molars, and mandibular second molars. The distance from the cementoenamel junction (CEJ) to the root groove and from the CEJ to the root division was measured. Mean CEJ to root groove distances ranged from 1.35 to 1.65 mm for maxillary first molars, from 1.49 to 1.89 mm for maxillary second molars, from 1.71 to 1.73 mm for maxillary first premolars, from 1.16 to 1.22 mm for mandibular first molars, and from 1.53 to 1.76 mm for mandibular second molars.

Why is short-term sentence recall verbatim? An evaluation of the role of lexical priming

By showing that short-term sentence recall can be significantly affected by words encountered in an intervening distractor task, Potter and Lombardi (1990, Journal of Memory and Language, 29, 633-654) argue that short-term sentence recall is often verbatim because of the availability of recently activated lexical entries during the regeneration of the sentence from its conceptual representation. We show that similar effects can be obtained even when bilinguals perform an intervening task in a different language from that of sentence recall, or when monolinguals perform an intervening task upon pictures. Furthermore, we show that the presentation of a word in P&L's distractor task does not, in any case, affect subsequent retrieval of a semantically related word as measured in a picture-naming task. We suggest that the effects on recall reported here and by P&L should be explained in terms of conceptual level interference at the time of recall. We also discuss the implications of our suggestion for the issue of the verbatimness of short-term sentence recall.