ABSTRACT. W e studied properties of saliva and of dental plaque which affect the caries process in an effort to understand the low prevalence of caries in patients with chronic renal failure. Plaque pH, before and following carbohydrate exposure, saliva pEI, and saliva composition were evaluated in children and adolescents with chronic renal failure (n = 10) and successful renal transplantation (n = 1 I), and in two comparison groups of healthy children with few caries (n = 15) and numerous caries (n = 15).Salivary urea nitrogen concentration was elevated in all subjects with elevated serum urea nitrogen concentration. Chronic renal failure subjects had significantly higher salivary urea nitrogen concentration than transplanted subjects. Plaque p H correlated directly with salivary urea nitrogen concentration and was significantly more alkaline in chronic renal failure than transplant or comparison groups. Salivary urea nitrogen concentration accounted for the majority of variability in plaque pH, salivary p H and salivary phosphorous contributed negligibly. Absolute p H drop following carbohydrate exposure did not differ among groups, but because baseline plaque p H was elevated for chronic renal failure subjects, minimum p H did not attain Received February 5, 1985; accepted March 13,1985. cariogenic levels. Our data support the hypothesis that the relative paucity of caries in patients with chronic renal failure results from alteration of plaque by metabolic end products of urea metabolism. Our data further suggest that transplanted patients whose renal function is normal may be a t increased risk of caries, especially if enamel hypoplasia is present and oral hygiene is poor. (Pediatr Res 19: 796-799,1985)Abbreviations CRF, chronic renal failure SalUN, salivary urea nitrogen concentration Children with CRF have relatively few dental caries (1, 2) despite common occurrence of conditions which should increase risk of caries. Poor oral hygiene (3,4) and enamel hypoplasia (1, 2) are prevalent in CRF, and dietary supplementation of calories (5) results in cariogenic diets for many CRF patients. In an effort to explain low caries prevalence we designed a study to evaluate properties of plaque and saliva which might affect the caries process.Demineralination and erosion of enamel by organic acid are major factors in caries development (6). Plaque bacteria produce organic acid as a product of carbohydrate metabolism (7). In

Computer-assisted instruction (CAI) holds significant promise for meeting the current challenges of medical education by providing consistent and quality teaching materials regardless of training site. The Computer-assisted Learning in Pediatrics Project (CLIPP) was created over three years (2000-2003) to meet this potential through multi-institutional development of interactive Internet-based patient simulations that comprehensively teach the North American core pediatrics clerkship curriculum. Project development adhered to four objectives: (1) comprehensive coverage of the core curriculum; (2) uniform approach to CAI pedagogy; (3) multi-institutional development by educators; and (4) extensive evaluation by users. Pediatrics clerkship directors from 30 institutions worked in teams to develop a series of 31 patient case simulations. An iterative process of case content and pedagogy development, case authoring, peer review, and pilot-testing ensured that the needs of clerkship directors and medical students were met. Fifty medical schools in the United States and Canada are presently using CLIPP. More than 8,000 students have completed over 98,000 case sessions, with an average of 2,000 case sessions completed per week at this time. Each CLIPP case has been completed by more than 3,000 students. The current cost of CLIPP development is approximately $70 per student user, or $6 per case session. The project's success demonstrates that multi-institutional development and implementation of a peer-reviewed comprehensive CAI learning program by medical educators is feasible and provides a useful model for other organizations to develop similar programs. Although CAI development is both time-consuming and costly, the initial investment decreases significantly with broad use over time.