Factors Associated with Extraction following Root Canal Filling in Adults.

Essentially, root fillings are performed to preserve natural teeth. Over time, however, some root-filled teeth will inevitably be extracted. The aim of this historical prospective cohort study in the adult Swedish population was to identify factors associated with extractions within 5 y of registration of a root filling. The cohort consisted of all those whose root fillings had been reported to the tax-funded Swedish Social Insurance Agency (SSIA) in 2009. Demographic data on the individuals registered with a root filling (sex, age, country of birth, disposable income, educational level, and marital status) were received from Statistics Sweden or the SSIA. Dental care setting, tooth type, and any registration of subsequent restorations within 6 mo were received from the SSIA. Multivariable regression analysis was used, and P < 0.05 was considered statistically significant. In total, 216,764 individuals had been registered with at least 1 root filling. Individuals (n = 824) without complete data were excluded from the analyses. After 5 y, 9.3% of the root-filled teeth had been registered as extracted. Logistic regression analysis found significant associations for all variables except country of birth, disposable income, and educational level. The highest odds ratios for extractions were associated with the type of restoration: teeth with no registration of any restoration and teeth with a direct restoration combined with a post were 3 times more likely to undergo extraction than teeth restored with an indirect restoration combined with a post and core. Overall, high odds ratios for extractions were associated with any type of composite restoration, including composite fillings and crowns combined with or without any post. In summary, after root filling in the Swedish adult population, several individual- and tooth-specific variables were associated with extraction. The reasons for the extractions remain to be studied further.

Demographic factors in Swedish adults undergoing root filling and subsequent extraction of a maxillary first molar: a comparative study.

AIM: To study the demographics of Swedish adults who had received a root filling, followed by extraction during the following 5-6 years in comparison with subjects who had undergone a corresponding root filling with an uneventful outcome. METHODOLOGY: The root filled maxillary first molar was chosen as the comparison model. The Swedish Social Insurance Agency provided data on all teeth reported as root filled in Sweden during 2009. A comparison group, equally large as the study group, was constructed by randomly selecting subjects with root filled maxillary first molars, which had not subsequently been extracted, that is, an uneventful outcome. Demographic data on the subjects were obtained from Statistics Sweden: country of birth, disposable income, educational level, age, civil status and gender. Chi-square, t-tests and logistic regression were used for statistical analyses. RESULTS: In the year 2009, 36 139 maxillary first molar teeth were reported to have been root filled, 4362 (12.1%) of which were then recorded as extracted during the following 5-6 year period. Only minor intergroup differences were noted: 86.5% of the study group were Swedish-born, compared with 84.4% of the comparison group (P = 0.007). Women comprised 53.2% of the study group and 50.5% (P = 0.01) of the comparison group. There was an association between extractions and gender as well as age; men had a lower odds ratio (OR) for extraction OR, 0.87; confidence interval (CI), 0.80-0.95. For every additional year, the chance for extraction was higher OR, 1.01; CI, 1.01-1.01. No other significant differences were detected. CONCLUSIONS: There was only little or no demographic differences between the study group, comprising Swedish adults who had undergone root filling of one of their maxillary first molars in 2009 and subsequent extraction during the following 5-6 years, and the comparison group, with uneventful outcomes after a corresponding root filling.

Quantification aspects of constant pressure (ultra) high pressure liquid chromatography using mass-sensitive detectors with a nebulizing interface.

The present contribution investigates the quantitation aspects of mass-sensitive detectors with nebulizing interface (ESI-MSD, ELSD, CAD) in the constant pressure gradient elution mode. In this operation mode, the pressure is controlled and maintained at a set value and the liquid flow rate will vary according to the inverse mobile phase viscosity. As the pressure is continuously kept at the allowable maximum during the entire gradient run, the average liquid flow rate is higher compared to that in the conventional constant flow rate operation mode, thus shortening the analysis time. The following three mass-sensitive detectors were investigated: mass spectrometry detector (MS), evaporative light scattering detector (ELSD) and charged aerosol detector (CAD) and a wide variety of samples (phenones, polyaromatic hydrocarbons, wine, cocoa butter) has been considered. It was found that the nebulizing efficiency of the LC-interfaces of the three detectors under consideration changes with the increasing liquid flow rate. For the MS, the increasing flow rate leads to a lower peak area whereas for the ELSD the peak area increases compared to the constant flow rate mode. The peak area obtained with a CAD is rather insensitive to the liquid flow rate. The reproducibility of the peak area remains similar in both modes, although variation in system permeability compromises the 'long-term' reproducibility. This problem can however be overcome by running a flow rate program with an optimized flow rate and composition profile obtained from the constant pressure mode. In this case, the quantification remains reproducibile, despite any occuring variations of the system permeability. Furthermore, the same fragmentation pattern (MS) has been found in the constant pressure mode compared to the customary constant flow rate mode.

Effects of fetal insulin infusion on glucose kinetics in pregnant sheep: a compartmental analysis.

A three-compartment model, consisting of fetus (F), uteroplacenta, and mother (M) was applied to quantitate the effects of fetal hyperinsulinemia on glucose kinetics in pregnant sheep late in gestation. The approach combines the Fick principle with isotope dilution of differentially labeled glucose isotopes, infused simultaneously to F [U-14C]- and M [2-3H]glucose. In the basal state, rates of umbilical glucose uptake (8.37 +/- 0.98 mg/kg per min) and fetal glucose utilization (7.38 +/- 1.13) were equivalent (mean +/- SE; n = 12). When fetal insulin was increased from 13.7 +/- 2.2 to a plateau of approximately 100 microU/ml, arterial glucose decreased from 18.9 +/- 0.8 to a new steady state of approximately 13 mg/dl (P less than 0.001). Whereas umbilical glucose uptake increased at 90 min and remained elevated thereafter (P less than 0.01), fetal glucose utilization increased only transiently at 60 min by 1.9 +/- 0.8 mg/kg per min (26%; P less than 0.05) and then returned to base line. Insulin's persistent effect, however, was evident from the sustained doubling of the glucose clearance rate from 39.3 +/- 5.9 to 66.6 +/- 10.5 ml/kg per min (P less than 0.005). No endogenous fetal glucose production was evident throughout the experiments. Maternal glucose production and utilization remained unchanged, although there was a small decline in M glucose concentration and an increase in glucose transfer from M to the uteroplacenta and F, from 33.9 +/- 8.1 to 48.1 +/- 7.0 mg/min at 60 min (P less than 0.01 by paired analysis). We conclude that fetal hyperinsulinemia initially lowers glucose concentration by transiently increasing fetal glucose utilization.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of exercise training on insulin sensitivity in adolescents with type I diabetes.

We investigated the influence of a program of exercise training consisting of three weekly sessions, each 45 min long, for 12 wk, on indices of physical fitness, glycemic control, and insulin sensitivity in nine adolescents with type I diabetes; six age-matched adolescents with diabetes of equivalent duration served as nonexercised controls. All subjects were instructed not to change dialy insulin dose or caloric intake. In the exercised group, maximal oxygen uptake during graded cycle ergometry to volitional exhaustion increased by 9 +/- 2.7% (P less than 0.01) and lean body mass increased by 4 +/- 1.8% (P less than 0.05). Insulin sensitivity, assessed via the euglycemic clamp technique at insulin infusion rates of 100 mU/M2/min, showed an increase of insulin-mediated glucose disposal from 274 +/- 33 to 338 +/- 28 mg/M2/min, representing an increase in insulin sensitivity of 23 +/- 5% (P less than 0.01). None of these indices changed in the control group. Despite increased insulin sensitivity, glycohemoglobin levels remained at 12 +/- 1% before and after the 12 wk of exercise training, indicating no improvement in overall glycemic control. No increase in hypoglycemic reactions was reported in either group. We conclude that exercise training may be a valuable adjunct in managing type I diabetes providing there is concomitant attention to diet and insulin. Exercise training alone, however, does not improve glycemic control, although it improves physical fitness and insulin sensitivity.

The Effects of Physical Training on Blood Lipid Profiles in Adolescents With Insulin-Dependent Diabetes Mellitus.

In brief: Fourteen adolescents (eight females and six males) with insulin-dependent diabetes mellitus (IDDM) participated in a 12-week exercise program consisting of three 45-minute sessions per week. Exercise consisted of calisthenic warm-up and stretching (ten minutes), aerobic movement to music (25 minutes at 80% V o2 max), and cool-down (ten minutes). The purpose was to determine whether and to what degree such training would bring about changes in blood lipid and lipoprotein profiles in such patients. The authors found a significant decrease in low-density lipoprotein cholesterol concomitant to an increase in V o2 max with no change in glycemic control. These findings support the beneficial effects of regular exercise for individuals with IDDM.

Fetal-perinatal catecholamine secretion: role in perinatal glucose homeostasis.

Secretion of catecholamines may play an important role in several of the adaptations that characterize the transition from intra- to extrauterine life including cardiovascular, respiratory, and metabolic events, specifically the initiation of endogenous glucose production following curtailment of the transplancental maternal supply of glucose. Maturation of neural and enzymatic pathways involved in catecholamine secretion occurs late in gestation; fetal hypoxia can produce a 20- and 125-fold increase in plasma epinephrine (E) and norepinephrine (NE), respectively. Estimates of turnover (approximately 2,000 pg X kg-1 X min-1) and metabolic clearance rates (20-40 ml X kg-1 X min-1) indicate active secretion and metabolism of E from fetal sources with negligible transfer from the mother. Simultaneously, there is maturation of functional alpha- and beta-adrenergic receptors. At birth, plasma E and NE rise three- to tenfold; plasma levels are higher in hypoxic infants and lower in prematures. Concurrently, glucagon increases three- to fivefold; cortisol and growth hormone also are high, whereas insulin remains low and poorly responsive to stimuli; the number of glucagon receptors increases, whereas that of insulin decreases. Acting in concert these hormonal changes activate glycogenolysis, gluconeogenesis, lypolysis, and ketogenesis. Glucose production and gluconeogenesis, absent in utero, become evident within hours of birth in both humans and sheep. The spontaneous surge in catecholamine secretion at birth may be the key event because infusion of E or NE to fetal sheep in late gestation simulates the metabolic and hormonal profile of glucagon and insulin as well as glucose production that normally only occur with separation of the placenta.

Prediction of adult height from height and bone age in childhood. A new system of equations (TW Mark II) based on a sample including very tall and very short children.

A new series of equations is presented for predicting the adult height of a child given present height and bone age. These equations (TW height prediction, Mark II) which replace the ones given in 1975 (TW height prediction, Mark I) are based on larger numbers of normal children, and more importantly on a sample that includes, for the first time, numbers of very tall, very short, and very growth-delayed children. In addition, equations are given for use when the increment of height or bone age, or both, over the previous year is known. These variates improve the prediction at most ages over 8 years in girls and 11 years in boys. The previously given parental allowance has been dropped. Typically 95% of the predictions lie within +/- 8 cm of the real value for boys aged 10 years, falling to +/- 6 cm for boys aged 15 years, or +/- 4 cm if their previous height increment is known. For premenarcheal girls the predictions lie within about +/- 6 cm at age 8 years; a figure which diminishes little till 13 years unless height and bone age increments are known, when it reaches +/- 4 cm at 13 years. For postmenarcheal girls the predictions are substantially more accurate.