A tooth can be injured by trauma such that it is loosened, knocked inwards into the jawbone, or out of the mouth. Treatment principles are somewhat different for primary than permanent teeth since the main concern here is not so much the preservation of the primary tooth but any damage that might have been caused to developing second teeth in the area. Here we are concerned mainly with permanent teeth followingtrauma, or have been otherwise loosened, and splinting indications and techniques using composite resins.
Following a traumatic event it is always necessary to make a thorough assessment including medical and dental history, clinical and radiographic examination. Some additional tests such as palpation, percussion, and careful evaluation of mobility may be required.
In cases where trauma has loosened a tooth but not dislodged it, (subluxation), there may be no actual need for active treatment but for medico-legal reasons dentists often see fit to be conservative and to apply some form of splint to help stabilize the loosened tooth, and this is most easily done by bonding with a light-curing composite following acid etching of the enamel. Dabs of composite resin can be placed on the buccal aspect (outside), of the affected tooth and stretched across to the adjacent tooth on each side. Once the composite is set there is a reasonably strong bond across three teeth. There is a possibility of the tooth pulp dying following trauma and thus the situation needs to be monitored with periodic pulp testing and radiographs. It is usual for a loosened tooth to firm up within two weeks or so, when the splint can then usually be easily removed with a scaling instrument.
Where a tooth is completed knocked out of the mouth (avulsed) it should ideally be kept moist by holding it in the mouth until a dentist can replant it. As long as the periodontal ligament has not dried out then there is a reasonable chance of the tooth being firm after a couple of weeks following splinting as previously described. If the periodontal ligament has dried out then replanting carries a risk of ankylosis unless some debridement treatment of the root is carried out first. Since the apical blood supply has been severed, however, there is also a high risk of pulp necrosis and thus root-canal therapy being required.
A bonded splint is ideal in these types of situation since it is passive and doesn’t put any strain on an already loosened tooth, and is non-irritating to soft tissues provided it is not too bulky. It is usually reasonably aesthetic, and it allows for pulp testing, and for endodontic treatment should that prove necessary. Since there is no covering of the incisal edges a composite bonded splint doesn’t interfere with the occlusion, as might a soft metal type, or acrylic overlay. The composite splint also allows for some slight physiological mobility that is believed to encourage healing of the periodontal ligament. The situation in a young person may be slightly complicated by an incompletely formed root, but monitoring the situation provides the basis for treatment under the latest guidelines.
It’s necessary to give a patient detailed instructions following such a traumatic incident, including keeping to soft foods, avoiding biting on the splinted teeth, and maintaining scrupulous oral hygiene by means of very careful brushing.
The concept of strengthening loose teeth by splinting in order to make the whole local unit stronger may sometimes be of use in treating patients with gum disease and consequent loose teeth. The first line of treatment, however, is always to try to reduce the microbial count in the pockets of gum around the teeth, since it is principally bacterial products that cause the damage to the gums. The treatment involves very thorough scaling and curetting in each quadrant (quarter) of the mouth, sometimes in conjunction with raising a gum flap and localized areas of open surgery, and sometimes in conjunction with the use of local antibiotics.
Following that it may be decided to splint the teeth together with composite bonding to give increased support to one another. Composite splinting can be made to allow for careful oral hygiene measures to be carried out, and in this way can sometimes extend the life of loose teeth that might otherwise have to be extracted.
Splinting by means of composite bonding can thus on occasions be useful for providing weakened teeth with support from neighbouring stronger ones, although it is usually not a permanent solution, and therefore only applicable in certain specific situations as outlined.