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Today at the Southwest Dental Conference I am presenting a half day program on appliance therapy. One of the common questions we manage when making appliances is “what type of appliance should I make?”. I don’t have a belief that any one appliance is superior to others. I do believe that each design of appliance works for a specific set of clinical indications and has a certain set of contra-indications or risks. Which design I use is individualized to the patient based on their exam findings and my clinical suspicion. 
The anterior bite plane appliance is a design I use commonly in my practice. The principle behind this appliance is that when back teeth are separated the elevator muscles don’t fire with the same force, thereby reducing the load across the system and allowing the muscles to release. The lack of posterior tooth contact also releases the Lateral Pterygoid allowing a seated condylar position to be recorded as part of the treatment planning process. This appliance design goes by many names, but the basic design is the same and the physical principles are consistent.
Indications for using an anterior only appliance:
- All muscle diagnoses
- Post-Op protection of restorations
- Clenchers with healthy joints
Contra-indications for using an anterior only appliance:
- Increased joint pain due to load
- Worsening symptoms
Risks of anterior only appliance use:
- Anterior tooth intrusion or posterior super-eruption with excessive use
- Inability to find ICP
This appliance design can easily be fabricated in the office while the patient is there. Additionally, without posterior contacts as the muscles release and the condyles seat no posterior interferences are picked up that require monitoring and adjustment, so the process is efficient.
This is similar to the “Roth Splint” in orthodontics.
I like the way you made this with the overlay for esthetics and then the acrylic bite plane added. This is much more esthetic than the Roth Splint.
Could you do a video of this fabrication?
Could you do a video of the fabrication of the mouthguard? We made our first one but we had a hard time doing the clear layer added to the colored layer. Still trying to figure that out!
Thank you for all of your accomplishments. They are wonderful!
I’ll post the fabrication video as Monday’s post!
Lee
Lee Ann, I would point out that in your splint design, the canines can occlude and thus the anterior belly of the temporalis muscle can fire and contract and elevate the mandible. I personally use an AMPSA (anterior mid point stop appliance) e.g Hornbrook, Nosti, Kois, Ritsco…) to erase muscle memory ad allow condylar seating and thus CR recording. Just my 0.02 cents! There are various designs for this type of appliance.
Roger,
You are absolutely correct. This type of appliance can be made with centrals only or to include the canines. Canines will increase muscle activity over simply having centrals. I find that for most of my patients this still works as a very efficient and effective appliance. I utilize multiple anterior teeth to balance the two reasons we alter occlusions, reducing muscle engagement and distributing forces. I do however have patients that need the canine contacts removed to get the intended benefit, although this is a very small number. Either way I think it is a great appliance design for the stated reasons. Thanks for adding this to the discussion.
Lee
Lee Ann
I have been placing anterior bite plane for Nightguard appliance. I have noticing some anterior open bite due to posterior super eruption. How do you prevent and manage anterior open bite issues?
I do a large number of these appliances, and this is a very rare problem when managed properly. These appliances are for night time use only, and if worn during the day you need to expect that you may see this more often. Even with just night time wear these patients need to be monitored over time. I give all of my patients the same instructions. “when you first wake up and take the appliance out, touch your teeth together. If the appliance is working you won’t feel your bite, but your teeth will touch someplace else. Then in fifteen minutes touch your teeth together and you should feel the bite you are used to. If it ever starts to take more then 15 minutes to find the bite you are used to, you need to call and come in.” There are two possible causes of bite changes. The most common is condylar seating due to deprogramming. The appliance is designed to do this, and sometimes it works so well the patient loses MIP. This never happens overnight, it is gradual, much more common when the appliance is worn during the day. The other cause is tooth movement, much less common. Could be posterior extrusion, or anterior intrusion. I check every patient for the amount of muscle activity reduction. If this appliance does not significantly drop elevator muscle activity and you put all that force on 2 lower incisors that is a higher risk then when it drops elevator muscle activity dramatically. The good news is it reduces muscle activity dramatically in most people. If you have a patient with an anterior open bite. Take upper and lower alginates, pour models and try to hand articulate them. If you can still reproduce MIP on the hand articulated models, the patient experienced deprogramming and lost MIP. If you can not find MIP on the hand articulated models then tooth movement occurred.
Hi Lee,
If you are still responding to these posts. Its now August 12, 2020.
I have a followup question. I have a patient wearing an anterior bite appliance (nightime only) and came in 2 years later for a followup. He exhibits (now) a 3-4mm anterior open bite with models that I cannot hand articulate positively (only certain teeth contacting) and same for CR-articulated models , so I assume posterior extrusion (in CR=CO). He refuses to have an MRI done for me to see his condylar/disc positions. My question is, “How do I treat this case to re-establish anterior guidance (regaining anterior contacts) and stabilize his posterior occlusion, so I can crown 5 posterior teeth that he has fractured cusps on going forward?”
(otherwise, asymptomatic and unremarkable)
And, “What would his total treatment plan consist of and what would my concerns be?” I couldn’t find any printed articles discussing this in the literature. Thank you very much!
I forgot to add that trial equilibration on CR articulated models resulted in the desired anterior contacts, but with the undesirable need for full coverage on all posterior teeth
(especially 1st & 2nd molars) and with the need for posterior perio crown lengthening to provide adequate tooth prep structure.
Need to also add that he does brux with the anterior appliance showing tracks on the acrylic.
I agree with you that the teeth have moved since you can not hand articulate. To me this rules out that it is simply condylar seating. Given this I am way less concerned about the need for an MRI. The solutions are equilibrate and do the required restorative or ortho. This is one of the risks of anterior only therapy, and although I don’t see it often I do enough of these appliances that I do see it, and I also see a small amount of nueromuscular deprogramming that seats condyles and the person forgets where MIP is. These can be great cases for ortho using Invisalign. Classically these patients clench and exhibit pretty good force. The Invisalign trays typically will have heavy posterior contact and act like a Dahl appliance intruding the posteriors and at the same time can extrude the anteriors. You need to prepare the patient for a temporary increase in muscle activity that may bring with it some headaches and muscle symptoms. You can also try a classic Dahl appliance, or traditional ortho. Another alternative is simply stop appliance therapy of any kind and see if the tooth to tooth contact applies the necessary forces in the posterior and allows the anterior teeth to extrude. Same symptoms may develop as above, and it it does not work in 3 months or so, ortho forces will be needed.
Thank you Lee for introducing the Dahl appliance to me; I did initially thought of making a posterior appliance that would “reverse” what the anterior did; but didn’t know if it should be inserted on the upper posteriors or the lower. I also did consider stopping the anterior appliance therapy and letting things settle on their own, but was too afraid, during night time bruxing,
he would fracture even more teeth. And lastly, I remember years back I restored a lower first molar with a composite under a rubber dam for close to two hours and afterwards, when I was checking his occlusion, he was only occluding on his second molar and I remember not understanding what was going on. I pretend nothing was wrong and dismissed him. He was fine the next day during a followup. Combining this episode with the current anterior open bite situation made me question his condylar/disc position and why I thought an MRI might give us some important info. Am I making this more complicated than it is? And have an MRI done later,
if needed? Thank you for responding and suggestions. I will look further into the Dahl appliance.
An MRI will not hurt, but since you can not hand articulate the models this open bite is tooth movement. He may have had a previous disc displacement however. Have you listened to the joints with doppler or s stethoscope? Does he have crepitus on rotation indicating a complete or medial pole displacement? You could also fabricate a full coverage appliance and track MIP on the appliance for awhile, if the bite is stable, again I would not feel compelled to gt an MRI, and again getting one isn’t going to hurt anything.