An ex vivo culture model for orthodontically induced root resorption.

OBJECTIVES: Root resorption is a ubiquitous although undesirable sequela to orthodontic treatment. Current methods to investigate the pathophysiology have certain limitations. In pursuit to understand and develop treatment modalities for orthodontically induced root resorption, the ability to manipulate cells within their natural extracellular matrix in a three dimensional organotypic model is invaluable. The study aimed to develop a laboratory-based organotypic model to investigate the effect of orthodontic forces on the periodontium. METHODS: Mandibular slices of male Wistar rats were maintained in Trowel-typed cultures at 37°C in 5% carbon dioxide in air for 7 days with test specimens subjected to compressive forces at 50 g and 100g by stainless steel springs. Tissue architecture and cell viability were maintained under culture conditions. RESULTS: Osteoclast numbers increased significantly in both test groups whilst odontoclasts increased in the 50 g group. Immunohistochemistry demonstrated increased dentine sialoprotein expression in both test groups, suggesting changes in mineralization-related activity due to mechanical strain. CONCLUSION: The study showed initial cellular and molecular changes of key markers that relate to root resorption in response to mechanical loading. CLINICAL SIGNIFICANCE: Severe root resorption may occur when forces applied are heavy or transmitted over an extended period and could lead to mobility and tooth loss. This ex vivo model can be used to investigate cellular and molecular processes during orthodontic tooth movement which may advance the clinical management of root resorption.

Health status and timing of onset of prenatal care: is there an association among low-income women?

We examined medical obstetric conditions predating pregnancy and current symptoms as predictors of the timing of the start of prenatal care among low-income women in Snohomish County, Washington. The investigation was a cross-sectional survey with retrospective record review. Subjects were 473 women who sought care through the community health center network, which was the only provider of prenatal care for low-income women in the county at the time of the study. Women with a history of two or more medical or obstetric conditions were more likely than those without such histories to seek prenatal care early in pregnancy. Women who, in the current pregnancy, had few physical symptoms were more likely to delay seeking prenatal care than symptomatic women. Among this relatively homogeneous group, sociodemographic characteristics were not associated with the timing of entry into prenatal care. The findings help to explain the patterns of prenatal care use of certain groups, and suggest avenues for intervention to improve use among low-income women.

Breastfeeding and weaning practices in rural Mexico.

This report describes the breastfeeding and weaning practices of rural women in two Mexican towns and the cultural beliefs upon which these practices are based. Interviews and focus group discussions were used to collect information. Women thought breastfeeding preferable to bottle-feeding. Eighty percent initiated breastfeeding and 69% gave colostrum. Breastfeeding was discontinued early (mean age 4 months). The mean age at which children were introduced to other liquids was 2 months (range 0-5 months) and to solids, 4 months (range 1-8 months). Women's decisions regarding infant feeding were influenced most by custom and advice from doctors and family members. In some instances medical advice conflicted with traditional practices. These findings suggest important avenues for intervention in hospital practices, education for health care workers, and in the development of health promotion services.

PIP: The impact of culture and community factors on breast feeding and weaning practices is examined by means of interviews among 35 rural women aged 16-43 years from Jalisco, Mexico, and by means of focus group discussions. Breast feeding practices are gleaned from information provided by mothers on their youngest child aged 2 weeks to 17 months for a 24 hour period prior to the interview. All study infants were given breast milk, supplements of water, and other liquids from birth. Fresh or powdered cow's milk was the usual supplement, except for 5 infants who received commercial formula. Boiled water was used in rehydrating powdered milk. Breast milk substitution was a bottle or cup given 2-4 times daily. The introduction of solid foods was made at 1 month to 8 months of age. Foods ranged from beans, tortillas, bread, pasta, fruit, chicken soup, flavored gelatin, to soft drinks. Between 9 months and 23 months, toddlers were fed the same foods in addition to vegetables, beef, fish, egg, cookies, and prepackaged cold cereal. The reasons given for not breast feeding were illness of the mother, a breast problem, insufficient milk, or an ill child. Colostrum was given for the following reasons: doctor's advice, the best interests of the baby, a woman's preference, custom, and no reason. Colostrum was not given for a variety of reasons including, for example, when the doctor advised against it or when a woman was ill or had a breast problem. In the three focus groups (27 persons), breast feeding was mentioned as preferable because of the added protection given the baby, the convenience of the mother, and the exchange between mother and infant. Other important factors were the improved health of the baby, the absence of cleanliness problems, and the milk was the right temperature. Exclusive breast feeding was recommended for a duration of 3-9 months. Breast feeding was withheld for 4-5 hours if a child had vomiting or diarrhea, or had been in the sun too long. Weaning was considered appropriate anytime between 2 months and 12 months of age. Weaning occurred when the mother was unable to continue or the child wanted to stop or had teeth. There was disagreement about how quickly to complete the process of weaning. Food was introduced at 2 to 6 months of age when milk was not enough to satisfy the child's hunger.

Variation in cesarean section rates among hospitals in Washington State.

OBJECTIVES: This study examined hospital characteristics and hospital population risk factors and their associations with hospital-specific cesarean section rates in Washington State. METHODS: Data were obtained from 1987 birth certificates. The study population included all hospitals that had 12 or more singleton live births. RESULTS: Hospital-specific cesarean section rates varied from 0% to 43% and were positively associated with proprietary ownership, size of delivery service, and the proportions of women who had complications or high-birthweight infants. The proportion of women who had late prenatal care was inversely associated with cesarean section rates. Although proprietary hospitals had higher cesarean section rates, their patient populations were lower risk than patients of public or teaching hospitals. CONCLUSIONS: Variation in cesarean section rates among hospitals cannot be fully explained by either hospital or patient population characteristics. A combined strategy may be necessary to lower unjustifiably high cesarean section rates.

Dental management of fibrous dysplasia.

This report describes two patients with monostotic fibrous dysplasia affecting maxillary alveolar processes. The long-term care for patient ML between ages 6 and 28 years included the transplantation of a premolar and a third molar tooth into the affected area, but the transplanted tooth 14 had to be extracted 6 years later. The patient JW, who presented at age 5 with an asymptomatic swelling in the left deciduous molar and first permanent molar region, was followed for 15 years. Teeth 24, 25, and 26 were developmentally absent. The roots of the deciduous teeth of both patients resorbed normally, and were replaced by tissue with the same radiographic appearance as fibrous dysplasia.

Reproductive rights and the medical care system: a plea for rational health policy.

Recently, there have been many challenges to women's reproductive rights and freedoms: court-ordered cesarean sections; criminal cases against women for prenatal child abuse; and attempts to limit the practice of mid-wifery, home birth, and the operation of alternative birth centers. In these cases, medicine has been complicit or proactive in attempts to control the behavior or health care options of pregnant women. We discuss medicine's role as an agent of social control, the medical reconstruction of problems that are social in nature, and the need for a more coherent policy framework to guide physician practices.

PIP: Reproduction issues are highly controversial. Women's legal right to abortion continues to be challenged, women's rights are being pitted against fetal rights, and there is concern about teen pregnancy, the appropriate use of reproductive technology, and drug and alcohol use during pregnancy. There has been, however, little attention to medicine's role as an agent of social control and arbiter of reproductive behavior, the medical reconstruction of and intervention in problems which are essentially social in nature, or of equity and social justice in reproductive health care. The authors discuss these latter issues in light of historical and more recent attempts to control the behavior of pregnant women. In the absence of current reproductive health policy, the medical profession makes arbitrary decisions in individual cases which may or may not reflect patient or community wishes. A more coherent policy framework and regulatory mechanisms to guide physician practice are needed. The authors discuss the problem in context, key questions, social discrimination in reproductive health care, choosing which services to provide, coercion and choice, and reproductive health policy as a solution.

Patterns of use of obstetrical interventions in 12 countries.

Recent obstetrical practice trends in 12 countries were surveyed. There was a 3-fold difference in caesarean section rates and a 10-fold difference in instrumental vaginal delivery rates among countries. There was a net increase in the caesarean section rate of all countries over the study period and a net decrease in the instrumental vaginal delivery rate of some countries. There was a decrease in the caesarean section rate during the last year of observation in Australia, Denmark and Finland. In general, countries with high caesarean rates also had high instrumental vaginal delivery rates. There was no consistent relationship between use of caesarean section and use of instrumental vaginal delivery, although in several countries increasing use of caesarean section was accompanied by decreasing use of instrumental vaginal delivery. Oxytocin use rates were associated positively with instrumental delivery but not with caesarean section rates. While it was not possible to determine the proportions of women who received appropriate obstetrical care, we can infer that a significant proportion of interventions were unnecessary or only marginally beneficial. Continued increases in rates of obstetrical intervention are unlikely to result in improvements in birth outcome overall and may pose a risk to mothers and their newborns.

Infertility in industrialized countries: prevalence and prevention.

We discuss the prevalence and aetiology of infertility and the relevance of this information for national infertility services and prevention programmes. The prevalence of infertility in industrialized countries has been said to be as high as 10-20%. This estimate, and the argument that little can be done to prevent infertility, have been used as justification for increased government investment in, or expansion of, services for medically assisted conception. However, population prevalence surveys indicate that far fewer couples of reproductive age are actually infertile. For example, a recent survey in the United States reported that 8.5% of married couples with a wife age 15-44 were infertile. 4% of the sample were childless and reported having a condition which impaired fecundity, while less than 2% were childless, had impaired fecundity and were over 35 years of age. Other studies show that nearly a third of couples have difficulty conceiving at some point during their reproductive lives but few actually remain childless. A significant proportion of infertility could be prevented through more aggressive application of standard public health measures.

Perinatal care in the Soviet Union: a time of transition.

Recent Soviet reforms in health care policy and financing are expected to have a significant impact on perinatal services. Efforts are under way to upgrade the care of pregnant and birthing women. This paper describes some aspects of the current system of perinatal care and prospects for future change.

Using art to understand children's perceptions of roles in physician's office visits.

As part of HealthPACT, a health consumer education program for children, third and fourth graders drew pictures in response to the question "What do you do in the doctor's office?" Based on content themes and the literature, a clinical assessment tool for the evaluation of HealthPACT drawings was developed.