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(the image above appears on the "Lack of Adverse Effects" page listed under Scientific Background)

The most obvious of condylar seating and resultant anterior open bite is when the patient originally presents with a class III anterior edge-to-edge bite.  The slightest seating of the condyle surperiorly/posteriorly will be displayed  as an inability to approximate the incisors.  This may not present itself until a few months after delivery of the NTI, although the patient will have reported significant resolution of symptoms.  If the patient has been clenching in this orientation since adolescence, the lateral pterygoid muscles are not tensed, but are in a normal working length.  The slow "encouragement" of the condyles to seat more posteriorly/superiorly by the elevator muscles allows the LPs to adapt to their new, longer working length (as the muscle tissue continuously regenerates).  (Diagrams from Dawson: Evaluation, Diagnosis, and Treatment of Occlusal Problems, 2nd edition)

One of the specific scenarios of the above description is the development of an anterior open bite (and is also described on the Frequently Asked Questions page), which can occur as a result of the seating of the condyles following normalization of the musculature.  This can only happen if the condyle(s) were in a position anterior and inferior to their optimal musculo-skeletally stable position, and then seat to a  more posterior-superior position.  This causes the mandible to pivot/rotate at the most posterior molars (thus giving the appearance of posterior supra-eruption), allowing the condyles to seat more posterior and superiorly, while the anterior mandible rotates posterior-inferiorly, which, depending on the original degree of incisor overlap, may present as an anterior open bite.

This is a rare development, and clinically can be observed to varying degrees in approximately 5% of those patients using the NTI-tss for pain relief and prevention.  Additionally, if this does develop, it does so following a relief of the patient's symptoms.  There is no method in advance to predict if any condylar seating will occur, or how much.

The vast majority of these occurrences can be restored to provide incisal biting by performing occlusal reduction of the interfering posterior cusp tips while the patient is in a protrusive incisal bite relationship.   However, in a small number of cases this will not be adequate to close the anterior incisal bite.  If the patient  desires to regain a functional incisor occluding relationship (many times the patient is so satisfied with their symptomatic resolution that they elect to do nothing more), a more involved restorative treatment plan may be required, including fixed restorations, orthodontic or orthognathic treatment.

As with any procedure, where a variety of outcomes is possible, all reasonable outcome scenarios should be disclosed.  For the patient, the NTI-tss may prove to be both a symptomatic treatment device, and a diagnostic device which demonstrates that the condyles were not in their optimal seated positions.  However, the treating dentist may not desire to be involved in the treatment modalities necessary to provide a occlusal scheme to the patient's satisfaction, in which case the dentist may elect to not provide treatment with the NTI-tss.