|
TPD Classic / TPD All-in-one / TPD Neo
Surgically assisted rapid palatal expansion (SA-RPE) is an established technique to correct maxillary constriction, buccal cross bite (unilateral or bilateral), anterior crowding and buccal corridors in adult patients.
Dental anchorage by tooth borne devices may present a number of complications, such as:
- possible loss of anchorage;
- periodontal membrane compression and buccal root resorption, cortical fenestration;
- skeletal relapse during and after the expansion period which makes overcorrection necessary;
- anchorage-tooth tipping and segmental tipping, instead of parallel expansion. (see clinical publications)
TPD, a bone borne device fixed on the palatal shelves, avoids these problems:
- no loss of anchorage since the abutment plates are fixed in the palatal bone;
- no or very little skeletal relapse can be expected since the actions of expansion and retention are immediately on the bone;
- no periodontal membrane compression, root resorption or cortical fenestration since the teeth are left untouched;
- no tipping of the teeth;
- no or very little tipping of the segments, since action is in a higher level on the vault. (see clinical publications)
We have to draw your attention to cases with extreme narrow palates. If the space between the right and left palatal crests is less then 12 mm, it is impossible to place the device.
Advantages
- Interchangeable modules make large expansions possible in narrow palates.
- Distractor is turned into fixator (retainer) with a blocking screw.
- Trans Palatal Distractor as fixator (retainer) is tissue-friendly, since it is entirely made of titanium grade 2.
Recommendations for the surgeon
Placing the Trans Palatal Distractor should be done according to the area that has to be expanded more. If the posterior area has to be expanded more than the anterior, place the device at the molar area. If the anterior area has to be expanded more than the posterior, than place the device at the first pre-molar area.
If brackets are already placed before the surgery, it is recommended to make a diastema of 1 - 2 mm between the centrals prior to the operation. This will prevent hiatrogenic damage to the central teeth or sockets during the splitting of the maxilla.
Remark: If one side moves more than the opposite side during the activation, stop activation at once and rotate the module in the opposite direction until it is symmetrical again. This may happen when the horizontal bony cut is not cut wide enough at the thick zygomatric buttress which causes blocking. It can be corrected immediately under local anaesthesia with a small incision at the buttress area and creating a new gap using a wide round burr to remove the obstacle.
Recommendations for the orthodontist
Orthodontic appliances can be placed before or after the operation. In case the appliances are placed before the operation, the arch wire has to be cut in two during the operation.
Fixation to posterior teeth of the incisors is needed to prevent them from drifting towards the distracted area, "Floating teeth phenomena ".
Orthodontic alignment can start 6 weeks or longer after the end of activation.
Instructions to communicate to the patient
|
