Contra-indications for the use of the Original NTI Tension Suppression System

The NTI-tss family of devices are to be used in the presence of symptoms, and are not for the general use of dental protection for simple bruxism.   Following the initial diagnostic confirmation of nocturnal parafunction, continuous use must then be regularly monitored by the prescribing health care professional. 

An anterior midline point stop (as provided by the NTI) has been shown to decrease (suppress) muscle activity, and allow the optimum musculoskeletally stable (anterior-superior) condylar position. In the event the patient’s condylar position is not optimal, the patient’s condyle may re-position more posteriorly/superiorly during resolution of their symptoms. This may result in a change of the patient’s occlusal scheme. Although this is not a result of "supraeruption", it may appear that way, due to the mandible pivoting at the distal most molar, possibly creating a lone contact (which may be adjusted through equilibration).

In the presense of MINIMAL INCISAL OVERLAP (for example, 1 or 2 mms, which is not uncommon following orthodontic therapy, as the mandibular incisor's brackets limit the degree of overlap), the potential for the development of an Anterior Open Bite is at its greatest.

This fact should be pointed out to the patient. If they do not consent to the possibility of a change of occlusal scheme (even though symptoms have improved), this method of therapy is CONTRA-INDICATED.

In the presence of advanced periodontal disease, the NTI alone should be used with caution.  An opposing device should be considered. 

Placing an NTI device that directly opposes a bridge (for example, an lower NTI that opposes a 3-unit bridge with a central replacement tooth) is contraindicated.  The preferred method would be to deliver the device over the bridge and distally extend the device to encompass additional teeth.

Not all occlusal schemes are compatible to the application of an NTI device without significant modifications to the device, such as in the case of severe flaring and/or rotation of the central incisors.  A custom device may need to be fabricated instead.

Following any apical or alveolar surgery to any of the teeth that support the NTI, discontinue use until completely healed.

In the event of severely worn centrals (for example, a loss of 50% of tooth structure) an unaltered typical NTI device is contraindicated, due to lack of available undercut for retention.   The device may need to be extended laterally to provide adequate retention.

If the patient insists on a "more comfortable" fit, that is, not as snug, confirm that the patient CAN NOT remove the NTI without using their hands. The NTI is contra-indicated if the patient is non-compliant with the appropriate retentive adaptation.

Use of SNAP is contraindicated if the supporting teeth have provisional restorations.  (use the ThermoPlasticBeads instead)

An unaltered NTI can not be placed in the presence of orthodontic brackets. 

If the Discluding Element opposes an large diastema, the DE must be altered so as not to wedge in between the opposing teeth.

The use of an un-altered device is generally contraindicated.  The practitioner is responsible to provide for a comfortable fit and non-irritating external surfaces.  The Discluding Element (or surfaces) must be customized for each patient's specific presentation, ensuring to at least not cause or complicate any new or pre-existing conditions.