Alligators Can Grow New Teeth: Why Can’t We? Although we grow new teeth, unfortunately, we have just two sets of them. Deciduous teeth or milk teeth are a smaller set of teeth provided to compensate for smaller jaw size in children. As the child grows, the jaw and skull size increases, and deciduous teeth are pushed out by a new set of permanent teeth. These larger teeth occupy the jaw completely and they remain with us until the end. This arrangement is actually an evolutionary ploy that enables children and adults to eat, speak and talk properly.
Could teeth cloning be on the horizon? Read on to find out.Continue reading
Why Is It Important For Us To Care For Our Permanent Teeth?
Every part of the human body can repair or regenerate itself up to a limited amount. In fact, this is what happens after trauma and injury. For example, the body repairs a bone fracture within a month and the bone can take up a normal workload again. However, the replacement tissue that appears in the injured area is distinctly different in appearance and function. It may act like bone and look like bone, but it is always of a slightly lower quality and functioning. As a result, tissue replaced after an injury is usually called scar tissue. This repair process is the same all over the body except for the teeth. After tooth damage, dental repair does not take place and scar tissue is never made.
Why Does This Happen?
The outer layer of a tooth is called as enamel and it is harder than bone. However, unlike bone that is a living structure, enamel is dead. It has no blood supply and it acts as an insulator on the tooth surface to protect against sudden temperature and acidity changes that are normal in the oral cavity. In case of poor oral hygiene, oral bacterial use salivary protein to create acids that eat away at the enamel. If the enamel was living, the patient would have been able to feel the enamel dissolving in the form of dental pain. However, this does not happen. As the enamel is dead, it is painlessly damaged until the acid eats deeper and deeper into the tooth, eventually reaching living areas of the tooth that then manifest as dental pain, swellings and infections. By the time this happens, it’s too late to do anything except dig out the decayed tooth tissue, sterilize the cavity and fill the space with a neutral dead restorative material. If the damage is extensive, dental repair does not take place at all but the dentist has no option but to extract the tooth. And tragically, once a permanent tooth is removed, no extra teeth will pop up in its place.
The Holy Grail of Dentistry
At present, most of dentistry focuses on preventive dental care (preventing cavities from happening) and restorative care (in which cavities or damaged teeth are restored partially back to health.) But for researchers, this has never been enough. The Holy Grail of dentistry has always been to try to grow or transplant new teeth into patients who have already lost teeth. If it possible to transplant corneas, livers, lungs and hearts, then why not teeth?
Current Research: Cloning Teeth
At present, most research focuses on stem cell research and cloning in which researchers plan to collect stem cells from bone marrow and clone teeth embryos to be implanted into empty sockets to grow new teeth. Although the theory is sound, it has not been realized into actuality. Animal trials are on to test the procedure and they have showed significant success but human testing is more than 10 years off in the future. Small teeth require about 60 days to grow in the lab, but the entire process of cloning is technique sensitive. Researchers are still not clear on how to actually carry out the tooth implantation and encourage adequate food supply inside the dental socket and in the patient’s mouth.
For this reason, alligator dentition has created a sensation. According to researchers at the University of Southern California, alligators have three different sets of dentition in their mouth. One consists of baby teeth, an extra set and a stem cell set that convert into new teeth at any time. In fact, alligators are known to grow more than 50 new teeth during their lifetime due to the unique dental stem cells present in their oral cavity. For researchers this is an exciting discovery. Human stem cells have to be guided into creating teeth but the training and scaffolding process could be cut short by using alligator stem cells. In an alligator, if teeth are lost, certain types of proteins are released that automatically activate the dental stem cells reserves and tell them to make new teeth. By identifying these proteins and using these stem cells, it could be possible to speed up the process of making and growing human teeth in the laboratory.
The good news is that human trials are on and they have provided positive results. However, until then, we’ll have to brush our teeth and visit the dentist (we aren’t alligators, after all!)