Ask The Dentist #18: What are retainers and why do I need one?

Posted Jan 11th, 2018

Ask The Dentist #18: What are retainers and why do I need one?

Ask The Dentist is a series of columns written by Dr. Mady to answer your questions about dentistry and oral health!

Dear Dr. Mady: I have been wearing braces for the past two and a half years and I will be getting them off in four weeks. My doctor said that I will need to wear some type of retainers to keep the teeth straight. Is this really necessary and what types are available? - Paulina in Las Vegas

Dear Paulina: When it is finally time for your braces to come off, your teeth will be straight and beautiful at last, but you won’t be finished yet. Most individuals need something to help retain the teeth in their new and proper position - retainers.

Impressions will be taken for your new retainers. Retainers are designed to hold your teeth in place while they settle into their new and final position. Depending on your case, your dentist or orthodontist will make recommendations on which type of retainers you will require, how long you will need to wear them each day, and for how many months or years. In some situations, they will need to be worn for life. Orthodontic retaining appliances resist the natural tendency of teeth to return to their pre-treatment positions under the influence of periodontal, occlusal (biting) and soft tissue forces, and continuing dentofacial growth.

Your doctor will fill out a prescription slip for his lab technician with instructions for the type of retainer and the specific design that they want the lab technician to follow when making your appliances. Some doctors have a technician in their office, but in most cases your retainers will be sent out to an orthodontic laboratory to be fabricated. 

These orthodontic dental retainers are appliances that are most commonly made of plastic and stainless steel wire (Hawley type), clear vacuum formed plastic, or can be a custom wire permanently bonded in the mouth. While the orthodontic retainer is holding the teeth in their new position, the surrounding bone and gums adjust around them to compensate for the previous movement. If the appliance is removable, the length of time that it must be worn will vary, but most teenagers will be advised to wear their orthodontic retainer at least until their early twenties. Immediately after braces are removed, the retainers should be worn at all times (except eating) during the first one to four weeks and then at least twelve hours per day for the first year. Some individuals wear them twenty-four hours a day except while eating. It all depends on what your doctor prescribes for your specific case.

The plastic/acrylic and stainless wire or Hawley type of retention appliance is the most common and has been used in orthodontics for many years. It is utilized mostly for retention in the upper arch, but can be used on the lower as well. In addition to retaining tooth positioning, it can also be used for additional minor tooth movements or even for space maintenance prior to orthodontic treatment.

The Hawley appliance is made of acrylic which can hold various wire attachments. In general, a Hawley constructed for the upper arch will cover most of the palate or roof of the mouth, and the lower Hawley will be shaped like a horseshoe. The wire attachments may include certain types of clasps and rests to help stabilize the position of the retainer. Small springs may also be attached to achieve tooth movement if desired. These springs will require activation by the dentist at certain time intervals to achieve the desired results if movement is needed.

The clear retainer is vacuum-formed over models of the straight teeth when one desires not to have a straight wire showing on the top or bottom. This retainer is see-through, and can sometimes be used with tooth whitener gels.   

The "bonded lower retainer" for the lower teeth is actually simple. There is a small diameter wire bonded to the back of each tooth between and including the lower cuspids.  It is also called a "bonded 3-to-3" in orthodontic terminology.  This is a retainer which will hold the lower six front teeth in position as long as the retainer remains in place. It can sometimes be used for upper front teeth also. In reality, the wire is unseen and unnoticed after the first few days.  You have to thread floss under the "bonded retainer" to keep it clean, or else it can become a plaque trap. That is about the only negative aspect of this fixed type.

The rationalization behind lower permanent retainers is prevention of a naturally occurring process that tends to crowd the lower front teeth as one ages. In the late teen years, the mandible or lower jaw will normally grow forward a bit, at the end of growth, crowding the bottom teeth against the inside of the upper front teeth. As long as the bonded retainer is in the lower, the teeth will stay straight and not move. 

Ask your dentist or orthodontist to show you samples of the different types of retainers that are recommended for you specifically. A decision can be made after taking cost and aesthetics into consideration. Good Luck!

If you want more information about orthodontics and cosmetic dental procedures, contact St. Clair Beach Dental Centre today.

Ready To Book? Contact Our Ridgetown Dentist Office Today!