Type 1 diabetes mellitus, xerostomia, and salivary flow rates.

OBJECTIVE: The Oral Health Science Institute at the University of Pittsburgh has completed a cross-sectional epidemiologic study of 406 subjects with type 1 diabetes and 268 control subjects without diabetes that assessed the associations between oral health and diabetes. This report describes the prevalence of dry-mouth symptoms (xerostomia), the prevalence of hyposalivation in this population, and the possible interrelationships between salivary dysfunction and diabetic complications. STUDY DESIGN: The subjects with diabetes were participants in the Pittsburgh Epidemiology of Diabetes Complications study who were enrolled in an oral health substudy. Control subjects were spouses or best friends of participants or persons recruited from the community through advertisements in local newspapers. Assessments of salivary function included self-reported xerostomia measures and quantification of resting and stimulated whole saliva flow rates. RESULTS: Subjects with diabetes reported symptoms of dry mouth more frequently than did control subjects. Salivary flow rates were also impaired in the subjects with diabetes. Regression models of potential predictor variables were created for the 3 self-reported xerostomia measures and 4 salivary flow rate variables. Of the medical diabetic complications studied (ie, retinopathy, peripheral and autonomic neuropathy, nephropathy, and peripheral vascular disease), only neuropathy was found to be associated with xerostomia and decreased salivary flow measures. A report of dry-mouth symptoms was associated with current use of cigarettes, dysgeusia (report of a bad taste), and more frequent snacking behavior. Xerogenic medications and elevated fasting blood glucose concentrations were significantly associated with decreased salivary flow. Resting salivary flow rates less than 0.01 mL/min were associated with a slightly higher prevalence of dental caries. Subjects who reported higher levels of alcohol consumption were less likely to have lower rates of stimulated salivary flow. CONCLUSIONS: Subjects with type 1 diabetes who had developed neuropathy more often reported symptoms of dry mouth as well as symptoms of decreased salivary flow rates. Because of the importance of saliva in the maintenance and the preservation of oral health, management of oral diseases in diabetic patients should include a comprehensive evaluation of salivary function.

Type 1 diabetes mellitus and oral health: assessment of coronal and root caries.

OBJECTIVES: The oral health of a large cohort of adult insulin-dependent diabetic patients (Type 1), diagnosed 24 years previously with juvenile onset, was comprehensively assessed. This paper describes the prevalence of coronal and root caries in this adult Type 1 diabetic population and evaluates demographic, dietary, behavioral, physiologic, salivary and medical variables associated with decayed and filled surfaces in the crown (DFS) or root (RDFS). METHODS: Type 1 diabetes mellitus subjects participating in this oral health evaluation had been monitored for 6-8 years as participants in the University of Pittsburgh, Department of Epidemiology, longitudinal study of medical complications associated with diabetes. Four hundred and six diabetic subjects received a comprehensive oral health examination during one of their regularly scheduled medical visits. Oral assessments included coronal and root caries, missing teeth, edentulism, periodontal status, soft tissue pathologies, salivary function and health behaviors. Sixteen diabetic subjects and one control subject were edentulous. Coronal and root caries data from the remaining 390 dentate diabetic subjects were compared with 202 dentate nondiabetic control subjects. RESULTS: The adult Type 1 diabetic subjects were not found to have significantly higher DFS rates as compared with our control subjects or published age-adjusted NHANES III findings. Both control and diabetic subjects had low decayed to filled tooth surface ratios. A linear regression model evaluated possible associations with coronal decayed and filled tooth surfaces (DFS) within the diabetic population. Significant factors included older age, women, fewer missing teeth, more frequent use of dental floss, more frequent visits to the dentist during the last 12 months, and diabetic nephropathy. The prevalence of RDFS was higher in the diabetic subjects as compared to recruited control subjects. Neither dietary behaviors nor glycemic control were found to contribute to coronal or root caries. CONCLUSIONS: Factors associated with presence of coronal and root caries and fillings are discussed. Possible causes and implications for the association between DFS and diabetic nephropathy are provided.

Dental implications of nutritional factors in young athletes.

A balanced and healthful diet is important for young athletes participating in sports. Additionally, nutritional recommendations for athletes must take into consideration the effects diet has on the developing dentition. The integration of oral and nutritional health guidelines will allow the dentist and the dietician to function as partners in providing counseling to young athletes. This article reviews caloric and nutritional requirements along with dental implications that may affect young athletes.

Identification of zinc proteins in rat parotid saliva.

The presence of unique zinc-binding proteins in human saliva is well documented. These observations have not, however, been extended to other species. The rat has been used extensively to study the salivary gland and its secretion, and it is therefore important to determine if the spectrum of zinc-binding proteins in this experimental model resembles that found in humans. To begin the analysis of zinc-binding proteins in stimulated rat parotid saliva, the saliva was fractionated by DEAE Sephadex and Sepharose 6B chaelate chromatography and the protein patterns analysed by electrophoresis. Zinc-binding proteins from the parotid saliva were identified by incubating Western blots with 65Zn and identifying any bound zinc by autoradiography. Comparison of the autoradiograms with the Coomassie blue-stained filter revealed several proteins with zinc-binding capacity. Isolation of the major zinc-binding proteins revealed an amino acid composition of proline 28%, glutamine 19% and glycine 15%, which is consistent with the amino acid composition of rat salivary acidic proline-rich protein. In addition to the proline-rich proteins, one other zinc-binding protein was analysed. The N-terminal sequence of this protein was found to bear a striking similarity (16 out of 20 amino acids) to secreted carbonic anhydrase VI of the mouse, a known zinc-binding protein. These data demonstrate that rat acidic proline-rich proteins, having an amino acid composition similar to that in humans, have zinc-binding potential. The data also confirm previous reports suggesting secreted carbonic anhydrase in rat parotid saliva.

Effects of glove powder on radiographic quality.

The use of powered rubber gloves in the provision of dental care has produced a new variable in radiographic quality assurance procedures. Wearing powder-coated gloves while processing X-ray films can reduce the quality of the images obtained on processed radiographic film. To ensure that the optimum quality of processed film images is achieved, the operator must be careful to prevent the contamination of the film and processing solutions with powder.

Tryptophan supplementation for nocturnal bruxism: report of negative results.

This experiment was designed to study the effect of L-tryptophan on nocturnal bruxism. Portable EMG recorders were used to monitor unilateral masseter muscle activity during sleep in eight patients identified as nocturnal bruxists. Following an initial baseline period, the patients were given, in a randomized double-blind study, either tryptophan (50 mg/kg of body weight) or a placebo for 8 days followed by an additional 8 days of reverse medication. Dietary patterns and food intake were monitored throughout the experimental period. No significant treatment differences in bruxing levels were found, suggesting that L-tryptophan supplementation in the absence of dietary manipulation is ineffective in the treatment of nocturnal bruxism.

Plaque fluid pH, calcium and phosphorus responses to calcium food additives in a chewable candy.

Fourteen subjects between 7 and 17 years of age with an equal distribution of low and high caries activity were given: (1) a 10% sucrose rinse, (2) a reference candy, (3) a reference candy with 3% dicalcium phosphate dihydrate, and (4) a reference candy with 0.75% calcium lactate on four different occasions. Plaque samples were collected before and at 15-min intervals after the sucrose rinse or food challenge for a period of 1 h on each occasion. Plaque samples were centrifuged and the extracellular plaque fluid analysed by a microtechnique for pH, total calcium and inorganic phosphorus concentration. There was no significant increase in calcium and phosphorus in plaque fluid for the group using candy with added calcium compared to the reference candy or sucrose rinse. There was no significant difference between the measurements in subjects grouped as caries active or inactive. The results suggest no benefit can be expected from adding dicalcium phosphate dihydrate and calcium lactate to candy to decrease demineralization during a cariogenic challenge.

Regulation of parotid salivary proteins by glucocorticoids.

Previous studies have indicated that adrenal-intact rats treated for one week with pharmacological doses of the synthetic glucocorticoid, dexamethasone, show a significant reduction in the proportion of proline-rich proteins and an increase in the proportion of amylase in rat parotid saliva (Johnson et al., 1987). In order to understand more fully the role of glucocorticoids in the regulation of salivary proteins, we performed bilateral adrenalectomies on groups of rats. Some of the adrenalectomized rats were treated with replacement-level doses of the synthetic glucocorticoid, dexamethasone. The food intake was monitored daily for both groups, and sham-operated pair-fed controls were included so that the effects of alterations of food intake could be separated from those of the experimental procedures. After eight to 12 days, uniformly stimulated parotid saliva was collected from these animals as well as from sham-operated controls fed ad libitum. The volume of saliva collected in 30 min was recorded, and the saliva samples were analyzed for concentration and composition of protein. Although the volume of saliva was not affected, parotid saliva collected from adrenalectomized rats exhibited a two-fold greater proportion of proline-rich proteins and reductions in other major secretory proteins: DNase, Fraction I, and Fraction V. The parotid gland secretory granules of adrenalectomized rats were more electron-lucent than in the ad libitum-fed controls. Treatment of adrenalectomized rats with dexamethasone largely prevented the changes in salivary protein composition as well as the alterations in secretory granule morphology.(ABSTRACT TRUNCATED AT 250 WORDS)

Regulation of salivary proteins.

Previous studies have shown that several factors--such as alloxan-induced diabetes, adrenalectomy, or removal of the thyroid-parathyroid gland complex--can influence the flow rate, protein concentration, and protein composition of rat parotid saliva. The present study was undertaken to explore further the influence of glucocorticoids and thyroxine on rat parotid saliva in hormonally intact animals. As compared with untreated animals, adult male rats treated with 10 micrograms dexamethasone per 100 g body weight for eight days demonstrated a 75% reduction in volume of parotid saliva secreted in response to a uniform stimulus. The protein concentration of the saliva was increased three-fold. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed relative decreases in acidic and basic proline-rich proteins and in a protein identified as Fraction V, while amylase was increased. The electron microscopic appearance of the granules was markedly different from that of the control, in that the granules exhibited an electron-dense periphery and core, with the remainder of the granule having an electronlucent appearance. In contrast, rats treated for eight days with 20 micrograms thyroxine per 100 g body weight exhibited a 50% increase in volume of saliva collected in response to a secretory stimulus. Although the concentration of protein was not different from that of the control, gel electrophoresis showed relative increases in acidic and basic proline-rich proteins and a decrease in Fraction V. Amylase was unchanged. The secretory granules of thyroxine-treated rats were electronlucent and amorphous. The granules appeared to coalesce within the cell.(ABSTRACT TRUNCATED AT 250 WORDS)

Hyperglycemic action of zinc in rats.

The effect of zinc on serum glucose, insulin and glucagon as well as liver glycogen was investigated in normal, adrenalectomized (ADX), and diabetic rats. Serum glucose was significantly elevated within 15 minutes after intraperitoneal administration of zinc (25 mumol) but returned to normal limits within 4 hours. Similar effects on serum glucose were noted with orally administered zinc. Significant depletion of hepatic glycogen in zinc-treated rats suggests glycogenolysis was responsible at least in part for the increased blood glucose. Adrenalectomy completely eliminated the hyperglycemic response to this metal, whereas adrenergic blockade with phenoxybenzamine and propranolol was effective in preventing hyperglycemia. The hyperglycemic response to zinc was not eliminated in diabetic rats. Administration of dexamethasone, alone or in combination with zinc, was unable to change serum glucose concentrations in ADX rats. Plasma glucagon was significantly elevated within 15 minutes but was reduced 6 hours after zinc treatment. Insulin was significantly depressed within 30 minutes after administration of zinc and eventually increased over controls by 4 hours after treatment. These data suggest that the hyperglycemic response to zinc depends on a mechanism, requiring an intact adrenal gland, which acts to produce a rapid alteration in blood glucose.

Endotoxin-induced changes in copper and zinc metabolism in the Syrian hamster.

The temporal response of zinc and copper metabolism to endotoxin administration was examined in Syrian hamsters over a 144-hour period. Serum copper was significantly elevated at 12, 24 and 72 hours after endotoxin, whereas serum zinc was reduced 4-48 hours after treatment. A brief elevation (8 hours) in liver copper concentration and a sustained (72 hours) increase in liver zinc concentration were also observed. The amount of zinc associated with liver metallothionein (MT) progressively increased with time, to a plateau by 24 hours and persisted at the elevated level until 72 hours after endotoxin treatment. In vitro translation of poly (A)+ RNA from liver polyribosomes showed that following endotoxin treatment MTmRNA activity was maximally elevated 6 hours after endotoxin administration and remained elevated 24 and 48 hours thereafter. Slab gel electrophoresis of serum proteins indicated changes in a stainable protein comigrating with purified ceruloplasmin after endotoxin administration. Pooled gingival tissue from endotoxin-treated hamsters demonstrated a consistently elevated copper content 12-144 hours after treatment. Endotoxin isolated from Bacteroides melaninogenicus was more effective in elevating gingival and serum copper and gingival zinc than Escherichia coli endotoxin. It was concluded that endotoxin administration elicits responses that result in enhanced metaollthionein mRNA activity. In addition, Cu and Zn concentrations in serum, liver and gingival tissue are influenced by different endotoxins to different degrees.