How do ultraviolet rays help your bones and teeth?

No. Long term exposure to uv light is unhealthy. However, we need some uv light from the sun to produce vitamin d. Vitamin d is important in regulating bone density and osteoporosis. Vitamin d deficiencies have been linked to tooth loss, and periodontal risk factors like low bone mass. Also vitamin d may act as an anti inflammatory agent and stimulate the production of oral anti microbial peptide.
SUN AND VITAMIN D. Sun's rays makes vitamin d in the skin which in turn helps absortion of calcium from the intestine . The absorbed calcium then makes the bone and teeth stronger.