This is why X-rays can penetrate your skin and soft tissue -- though not bone -- while sunlight mostly reflects off your skin.

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Biolase's Waterlase system uses a patented combination of water and lasers to precisely cut hard tissues (bone and teeth) and soft tissue (gums) with minimal damage to surrounding areas.

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The small, soft, edible bones of fresh sardines and smelts and canned bone-in fish like salmon are valuable sources of calcium.

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