Last week I talked about working with the provisionals on a patient I believe has a restricted envelope of function, mentioning that he reported waking with a headache the first few mornings after we placed the provisionals. I believe he needs more freedom in the anterior, and breaking the provisionals and the morning headaches support this theory. Patients who need more anterior freedom can present with signs and symptoms that affect their teeth, muscles, joints or all three. I find it helpful to puzzle through what is happening anatomically as a way to make sense of signs and symptoms I see.
Patients who are trapped or locked in the anterior can either spend significant time in this position with their posterior teeth touching, try to create more space, or move their mandible forward and rest in a forward position. Each of these adaptive strategies and the amount of time the person does each one create the patient’s presentation. The next question to ask yourself is what is the position of the condyle , is it being pushed posteriorly, and what are the muscles doing to protect the joint and the teeth? Each patient presents with a unique combination of signs and symptoms, but their combination can be overlaid on their occlusion and what they do with their teeth. Here is a list of the most common signs & symptoms I see in patient’s with a restricted envelope of function.
Dentition:
- Upper Anterior lingual wear
- Lower Anterior incisal edge and labial wear
- Upper anterior lingual ledging
- Anterior fremitus/mobility
- Anterior diastema opening
- Upper anterior flaring
- Loosening or fracturing anterior provisionals/restorations
Joints/Muscles:
- Retrodiscal tenderness/pain
- Digastric tenderness/pain
- Posterior Temporalis tenderness/pain
- Elevator Muscle tenderness/pain
Hi Lee,
I have seen this a few times and understood it to be restricted envelope but how do you treat it.
I would assume the wear generated in the palatal of the upper as per your pic is the pathway required and the dentition has formed this itself so a custom incisal guidance table around this but surely to prep the palatal to allow a crown say would then reduce the thickness here even further resulting in exposure?? Does it require ortho?
Also if a patient has reduced funds would an Nti or flat anterior bite plane appliance help reduce this issue at all or is this being created during daily function rather than any contribution from nocturnal parafunction?
Many thanks and love the blog!
Chris UK
Chris,
Treatment will depend on the patient, as you mentioned their interests and finances. The solution for a restricted envelope of function is some combination of increasing overjet and decreasing overbite. This can be accomplished many ways, here are some examples. Procline the upper anteriors, retrocline the lower anteriors, intrude upper or lower anteriors, open VDO, shorten lower anteriors with equilibration. This is just a few that pop to mind. These can be accomplished restoratively or with ortho depending on the clinical situation. I agree with you that a custom incisal guide table is a must for a patient with a restricted ebvelope of function no matter how we solve it. In this case I did have the challenge of not wanting to prep the lingual of these teeth and risk endo and structural failure. This patient had a shift from centric relation to intercuspal position that created a 2 mm vertical opening at the anteriors when he was in contact with his first point of contact. I equilibrated him seating his condyles, but only until I had captured the premolars in intercuspal position and used the space in the anterior for restorative clearance. In this way I opened his vertical dimension in the anterior,but minimized the change to the length of the muscle sling.
Lee
Hi Lee,
Won’t just removing the slide provide enough space we’re looking for?
Usually, after equilibration and once the ICP and RCP coincide and the slide is removed, you get some space in the front teeth as a result. Wondering if that could be enough to solve the restricted envelope of function.
Thanks
This is very commonly seen with Class I Divison 2 adult patients. As teeth 8 + 9 continue to retrocline due to environmental forces, the dental and TMD symptoms mentioned in this blog worsen. Comprehensive orthodontic treatment by a board certified orthodontist will relieve TMD symptoms and make ideal restoration of upper and lower incisors possible. Ideal functional occlusion can then be restored. The patient will look great and be healthy and happy!
Thank you for writing this blog!
Hi Lee this is so interesting..I am sure you have been very busy but the case I e-mailed you has those very similar traits…thank you for sharing this case with us!!!
Hi,
Ive have had many patients with this prblem, by adjusting centric interferences as Dr. Lee did, and adjusting the oclussion also by aposition (building centric stop) you can find space for anteriior retorations. Usuallly tmj synthoms decrease by new more fisiologic position of mandible.
The problem is when oclusion in centric is similar to mip. Then you must open VDO with complete rehab, overlays, crowns to replace older ones, etc..
Just one comment on the case, in my opinion there is some dental erosion, you can see isles of dentinal exposition, this is very common in these days.
Carlos A..