Permanent retainers or bonded retainers are used in cases where prolonged retention is needed after active orthodontic therapy. It can be made from multi-strand wire, which is bonded with composite resin to the inside surfaces of your teeth.
Permanent retainers are important for maintaining newly moved teeth in position long enough to stabilize their correction. Therefore these retainers are required for accurate tooth positioning. Components that make up a permanent retainer are responsible for mediating tooth movements.
Permanent retainers have both pros and cons compared to removable retainers. Although it is easier to use than removable retainers, it requires more attention in handling and cleaning.
Why we use permanent retainers?
Orthodontists may recommend permanent retainers after you finish an orthodontic treatment. These appliances help to stabilize the position of your teeth.
In the active phase of orthodontic therapy, malposed teeth are moved into the desired position. But, these teeth must be mechanically supported until the gingival and periodontal tissues reorganize in their new position. Because these tissues are affected by tooth movements during the therapy. Otherwise, any correction achieved by the orthodontic treatment could fail which is referred to as a relapse.
Principal functions of the permanent retainers
• To allow physiological recovery of the supporting tissues.
• To minimize the effects of maturational changes within the dentofacial complex.
• To maintain the position of the teeth that have been placed in an unstable position.
• To allow neuromuscular adaptation to the corrected tooth position.
Components of the permanent retainers
Permanent retainers consist of three main components.
● Brackets and molar tubes – These are bonded directly to the tooth crowns, or in the case of molar tubes, often welded to stainless steel bands that fit around the tooth.
● Archwires – Attached to the brackets and pass through the molar tubes.
● Auxiliaries – Include bracket ligatures, pins, elastics, springs, ligature wires, and fixed devices for anchorage and support.
Permanent retainers for bottom teeth
Late growth of your lower jaw in the late teen years (16 – 20 ) results in the crowding of lower incisors. If the lower incisors have previously been irregular, even a shallow degree of differential growth of the lower jaw can cause incisor crowding.
A permanent retainer called fixed lingual retainer is used to hold these teeth in alignment. This retainer is attached only to the canines and resting against the flat lingual surface of the lower incisors. It prevents the incisors from moving lingually. You can place a bonded retainer on all or some of the bottom incisor teeth. In this case, a heavy wire of 28-30 mm, should be used for a long-lasting bonded retainer.
Permanent retainers for top teeth
A diastema is a gap between your two upper front teeth. In this situation, teeth must be permanently bonded together to maintain the closure of the space between them. A removable retainer is not suitable to treat central diastema. Therefore, the best retainer for this purpose is a bonded retainer. By using bonded retainers, teeth are held together while allowing them to move independently during function. Therefore, a flexible lighter wire of 17.5 -19.5 mm is used for bonding purposes.
• Severe rotations.
• Teeth with reduced periodontal support.
• Severely displaced teeth when corrected.
• Surgically corrected cases.
• Sustenance of spaces in the dental arch.
Types of bonded retainers
Banded canine to a canine retainer
• Commonly used in the anterior region of lower jaw.
• Canines are banded by a thick wire which is contoured over the lingual aspect and fastened to the canines.
• These bands can cause poor oral hygiene.
Band and spur retainer
• Used for orthodontically corrected tooth due to rotation.
• The moved tooth is banded, and spurs are cemented onto the bands to overlap the adjacent teeth.
Removal of permanent retainers
You may need to remove your permanent retainer for several reasons.
• Damages caused by biting hard foods or other types of external impacts.
• When calculus builds up against the surface of your teeth.
• Ongoing discomfort or pain caused by the retainer.
If you need to remove your permanent retainer, do not attempt to do it at home on your own. Always pay a visit to any highly experienced orthodontist. He will remove the dental cement with the drill and then ease the retainer away from your teeth. Finally, the surface of the teeth will be cleaned and polished.
Cost of a permanent retainer
A permanent or bonded retainer may cost between $150 – $ 500 for one.
Broken permanent retainer
There are several reasons why your permanent retainer may break. Permanent retainers are bonded to the lingual surface of your teeth by applying a material called dental composite. This bonding material may get thinner in repeated abrasions from chewing hard foods and brushing too hard using the wrong toothbrush. Also, a higher degree of external impact on your teeth may cause your permanent retainer to become debonded from your teeth. Additionally, over time the wire may lose its strength and eventually break.
If you take care of your mouth and the retainer well, a permanent retainer can potentially last for up to twenty years. But it is advisable to have some maintenance or a repair every couple of years if needed. If you discover your permanent retainer is broken, you should meet your orthodontist as soon as possible.
But until you visit your orthodontist, or if it is difficult to get to the clinic immediately, you can take
several actions to minimize the damage.
• Avoid eating hard foods.
• Avoid activities and sports that may affect your teeth externally.
• Use an antibacterial mouth rinse to prevent the growth of bacteria – because, after the damage, the bacteria reach previously inaccessible places.
• Wearing a mouth guard at night can help prevent teeth from moving and protect the permanent retainer while you sleep.
Permanent vs. Removable retainer
Advantages of permanent retainer compared to a removable retainer
• Due to its flexibility, it allows for physiological tooth movement while maintaining the alignment of teeth.
• Maintain unstable occlusion.
• Minimum effect on the way you speak.
• It is permanently cemented behind your teeth, so no need to spend time taking them out and putting them back in every day.
Disadvantages of permanent retainer compared to a removable retainer
• Possible oral hygiene difficulties.
• Localized relapse if the retainer gets dislodged partially.
• Risk of decalcification and dental caries.
• Take a considerable amount of time to bond a permanent retainer to your teeth.
• Brushing and flossing your teeth after bonding a permanent retainer can be a bit
Flossing with a permanent retainer
Permanent retainers are easy to use compared to removal retainers but can be tricky to keep them clean.
Here is how to clean a permanent retainer in a few steps.
• First, pass a piece of floss through the threader and then insert it beneath the wire.
• Pull the floss until it is beneath the retainer.
• Once beneath the wire, you can floss between those like normal.
• If the wire is glued to each tooth, you will need to pull the floss out and reinsert it between each tooth.
• If the wire is glued to just the teeth on the ends, then you will be able to put the floss through once and continue to floss all of the teeth behind the wire.
• Make sure to floss beneath the retainer every day. This will become quick and easy with practice.