A. Approximately 1x109 CFU of Fn 12230, US1 (∆fadA), and lam suspended in carboxymethylcellulose (CMC) were orally administered to C57BL/6 mice three times a week for 10 weeks. CMC alone was administered as a control. Maxillae from mice inoculated with CMC alone (n=5), Fn 12230 (n=5), US1 (∆fadA; n=5), and lam (n=4) were harvested and fixed in 4% paraformaldehyde and stored in 70% ethanol, followed by microCT (μCT) scanning using a Scanco vivaCT 80 system at 55 kVp, 145 µA, and 250 ms integration time. Shown in the figure are reconstructed grayscale images. ImageJ was used to measure difference in bone height from the cementoenamel junction (CEJ) to the alveolar crest between palatal roots of first and second molars (see arrows). B. The average bone loss of each group shown in (A), with the lines above each bar representing standard deviations. *p< 0.05. **p< 0.01 (t-test). 