The temporomandibular joint (TMJ) connects the lower jaw to the skull. You can feel your two TM joints and their movement by placing your fingers directly in front of your ears and opening your mouth.

We see and hear about hearts everywhere. A long time ago, people even thought that their emotions came from their hearts, maybe because the heart beats faster when a person is scared or excited. Now ...

What Is a Urinary Tract Infection? A bacterial urinary tract infection (UTI) is the most common kind of infection affecting the urinary tract. Urine, or pee, is the fluid that kidneys filter out of ...

Testicular torsion is an emergency condition. It happens when the spermatic cord, which provides blood flow to the testicle, rotates and becomes twisted. The twisting cuts off the testicle's blood ...

Cystic fibrosis (SIS-tik fye-BROH-sis) is an inherited condition that causes the body to make thick, sticky mucus. The mucus causes problems in the lungs, pancreas, and other organs. People with ...

A wet dream — also called a nocturnal emission — is when a male ejaculates or "cums" while sleeping. During ejaculation, semen (the fluid that carries sperm) comes out of the penis. When you wake up ...

Inhalants are things that are breathed in (inhaled) to give the user an immediate rush, or high. They include glues, paint thinners, dry cleaning fluids, gasoline, felt-tip marker fluid, hair spray, ...

Pectus excavatum is when the ribs and sternum (breastbone) grow inward and form a dent in the chest. This gives it a concave or caved-in shape, which is why the condition is also called "funnel chest" ...

Rohypnol (roe-HIP-nol) is sold in some countries as a sleeping pill, but is illegal in the United States. Because it can cause extreme drowsiness (or "blackouts"), it is often used in date rapes. This ...

What Is Fetal Alcohol Syndrome (FAS)? Babies whose mothers drank alcohol during their pregnancy can be born with birth defects and developmental disabilities. The problems that can happen when babies ...

Communicating with our kids is one of the most pleasurable and rewarding parts of parenting. Children learn by taking in information through daily interactions with us and the world around them. The ...

If I sometimes stay up all night and don't get any rest, will that affect my growth? It could. A single night of no sleep will not stunt growth. But over the long term, a person's growth may be ...