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What are the indications and contra-indications? |
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A
properly bonded veneer, cemented crown, or bonded restoration is not a
contra-indication to place an NTI over those restorations. In
fact, many times an NTI is recommended to use in the protection
of those restorations. (An NTI will not be able to "pop off"
a well bonded veneer, nor will it remove a properly cemented crown).
In the diagram, the mandible is in a left excursive position. Without an NTI in place, the right lower canine would have been able to damage the distal incisal corner of the veneer bonded to the upper right central incisor. |
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Veneers on the lower incisors may be at risk in the above
example.
The Discluding Element may chip off the incisal porcelain that wraps over the incisal edges if the porcelain is not at least 1.5 mm thick. If maxially and mandibular veneers are being placed as part of the protocol to restore previous damage from bruxism, opposing NTI devices may be considered. See uses for the Universal Device. |
| Prior to delivering a NTI-tss for the protection of esthetic restorations, interview the patient regarding any signs and/or symptoms they may have of muscular parafunction (for example, if they feel good (or not) upon waking). 20% of all adults have some degree of nocturnal muscular parafunction. If the patient reports some degree of symptoms, they should be informed of the potential resolution of their symptoms and accompanying possible changes in condylar position, resulting in a change in occlusal scheme. For example, if an NTI-tss is planned following the delivery of porcelain veneers, deliver the NTI-tss a couple of weeks prior to preparations. In the event there is condylar repositioning (potentially opening the anterior bite), either the NTI-tss can be discontinued, or posterior equilibration and design of the veneers can re-establish the occlusal relationship. | |
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I certainly agree that far greater than 20% has some degree of nocturnal parafunction, but I guess what I was getting at is the symptomatic crowd who neither they or their dentist has any clue that they are primary clenchers. For example, let's some some seemingly well-put-together 32 year old gal wants 16 total veneers. She always has her make-up juuuuust right, and is quite pleasant. But get this, she might be living with a level 3 headache (on a 0-10 scale), which occasionally goes to migraine. Zero TMD signs/symptoms. Pure clencher. For the last 20 years. So the veneers go in, and an NTI follows. Three months later she comes in and can no longer incise things! She has developed an anterior open bite that no amount of NOT wearing her NTI will reverse.... Huh? Wha? See, sometimes, as the permanent molars come in, little kids can start to become pretty good clenchers. The mom and dad come to know their child as one of those who can get headaches from: school, not enough sleep, something they ate, blah, blah, blah. NONE of those things is painful, but no one has an explanation of why these kids get headaches.... Anyway, (here comes my JimBoydian Hypothesis, BTW) their clenching holds their mandible still as their skull/temporal bone continues to grow, back, up, and away from the condyle (the end result is a condyle sort of "down and forward"). Since they are primary clenchers, the condyles are perfectly stabilized and protected. No strain on them at all! So 20 years later, the occasional headaches have developed into Chronic Daily Headache (that's a medical diagnosis, BTW) with occasional migraine attacks (uh, er, ummm, if some of you didn't know already, I'm also describing my life). They will go to every/any/all doctors who treat headaches. They've learned to live with it. Since they don't feel fabulous, at least they can try to LOOK fabulous.. Since you're just a dentist, and in their mind would not know the first things about her headaches, she would never, ever, bring it up.... In fact, if you ask her, "Do you get headaches?", she might easily say "No". (In her mind, a daily 3 is NOT a headache...that is reserved for pain levels at say, 6's and above). Sooooo, in her effert to LOOK BETTER THAN SHE FEELS, in go the veneers, and an NTI follows. A few months later, the condyles have seated (it takes a little while because they don't wear the NTI during the day, and lose ground from the previous night's use), and the anterior bite relationship changes, perhaps even presenting with an anterior open bite. Even though they haven't had a migraine for the last 6 weeks (instead of their usual 4 per month), they simply assume that they can go maybe a month or so without a "bad one". And since they ignore how they feel anyway, it hasn't hit them that as their bite opened, their life was changing. (sometimes, the lower teeth get sore because the degree of condylar seating has allowed the posterior teeth to occlude even with the NTI in place...something to address there). The quick way to avoid a long, drawn out interrogation of the
patient,
is to do a switcheroo and ask, "When you wake up, do you fee
FABULOUS?"
They will look at you kind of funny, and hesitate before they begin a
rationalization
for how they feel... when they do, DING!
So what I was getting at was that around 20% of the (female) population are these symptomatic primary clenchers, and they get veneers, too, so watch out. -El So-do-the-NTI-FIRST-and-begin-the-veneers-a-few-weeks-later-to-avoid-this-awkwark-potential-altogether-O~ |
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