Question
Our son (15) will soon be able to remove his fixed braces (external brackets). In order to be able to maintain the success of the tooth correction in the long term, so-called retainers are attached today. There are apparently two systems for this. A fixed retainer, which is bonded directly to the teeth as a wire, or a removable retainer made of plastic, which is usually worn at night. Which system is better? Do I need a new impression?
Short answer
Whether wire retainer or retention splint: both variants have advantages and disadvantages. The wire retainer is more reliable for teenagers because they don't have to remember to insert the splint every evening. If you forget to do this several times, the teeth can shift again. It is possible to switch to the splint after the first few years.
Our teeth are not directly fused to the jawbone, but are only connected to the bone with many small tissue fibers. This makes it possible to move the teeth within the bone. Incidentally, this ability is present throughout life. The position of the teeth can be corrected right into old age. The force required for this is generated by the braces. The bone is dissolved in the direction of the force in which the tooth is to be moved and attached to the back. The connecting fibers are continuously formed anew.
Stabilization of moving teeth
A tooth that has reached its destination must be fixed in place for years, as otherwise there is a risk that it will move back on its own. This is usually done with a bonded wire (wire retainer) on the inside of the teeth, which is not visible from the outside, or with stabilization splints, which are only worn at night.
The wire retainer
It is glued to the invisible inside of the teeth by the dentist and cannot be removed by the patient. The advantage is that the teeth stay in place without having to think about anything. Only regular check-ups and hygiene sessions are necessary, as the adhesive can come off the individual teeth. The disadvantage is that more tartar forms, as hygiene is limited locally.
The rail
Retention splints are made of clear plastic and fit exactly over the entire dental arch of the upper or lower teeth. They are worn at night and can be inserted and removed by the patient themselves. The advantage is that there is nothing foreign, i.e. no wire, in the mouth during the day and nothing interferes with oral hygiene. One disadvantage, however, is that the splint could be forgotten before going to bed and the teeth could shift again. Accordingly, the splint would no longer fit after several nights, as the teeth would have already shifted irrevocably.
When, what?
A new impression usually has to be taken to fabricate both types of retainer. One exception is the InvisalignÒ procedure, for example, in which the teeth are actively moved with splints without visible wire. In certain cases, it is possible to switch directly to the retention splints without taking an impression.
Personally, I recommend bonding wire retainers for at least the first three years, as the teeth can shift very quickly during this phase. If necessary, the wire can then be removed and switched to the night splints. After this time, the shifting of the teeth is less pronounced if the splint is forgotten. The wire retainer is certainly the most reliable option for teenagers. What teenager wants to think about a retention splint every evening? However, the patient or their parents should help decide which type of stabilization is best for them.
Author: Dr. med. dent. Jürg Eppenberger
Published in: Neue Luzerner Zeitung on December 14, 2015