RDP Pilot: Testing a Multifactorial Caries Model for Pediatric Patients with Cystic Fibrosis

P.I.: Donald Chi, DDS, PhD
Associate Professor,
Oral Health Sciences,
School of Dentistry

Dental caries is caused by chronic intraoral bacterial infections involving Streptococcus mutans. The current paradigm in pediatric dentistry is that children and adolescents with CF are at low risk for dental caries. The antibiotics used chronically as part of CF treatment are thought to protect against caries. However, a recent systematic review authored by the PI suggests loss of protection against caries as children with CF enter adolescence. A potential explanation is that the life-protecting antibiotic regimens used to treat CF change as children with CF get older. Most children with CF use penicillins, which kill Gram-positive oral bacteria that cause caries (S. mutans). Adolescents with CF also use inhaled tobramycin, which does not kill Gram-positive oral bacteria. In addition, tobramycin may create selective ecologic pressure in favor of caries-causing bacteria because it kills Gram-negative oral bacteria. In addition, permanent tooth decay rates for patients with CF are greater than the U.S. mean caries rate, which suggests that caries in adolescents with CF is an important but overlooked issue. These observations warrant a critical reevaluation of a potentially flawed paradigm. We will collect primary clinical and survey data to achieve the following Specific Aim:

To investigate the medical, biological/intraoral, and behavioral risk factors associated with caries for 35 children (ages 6 to 11 years), 35 adolescents (ages 12 to 17 years), and 30 young adults (ages 18 to 25 years) with CF.

We will recruit and enroll 100 children, adolescents, and young adults with CF from Seattle Children’s Hospital. From these participants, we will collect survey data (from parents), saliva samples, and oral health data. The data generated from this pilot study will help refine the model of risk factors for dental caries and form the basis for a R01 grant application that proposes a longitudinal study of caries risk factors in children, adolescents, and young adults with CF. The long-term goal is to develop a multilevel clinical intervention to prevent caries in CF patients.

Our main study hypothesis is that adolescents with cystic fibrosis (CF) are at increased risk for dental caries compared to children with CF. We will test our hypothesis through the following Specific Aim:

To investigate the medical, biological/intraoral, and behavioral risk factors associated with caries for 100 individuals with CF.