In recent articles, I've been going over the proper treatment for patients with failed dentition due to pathway wear. As clinicians, it's very important to understand how we can create guidance for restorations in these types of patients.

When it comes to defining what the envelope of function is, I believe we need to define it in two ways:

"Dental" Envelope of Function: This is the static relationship that we as clinicians can control. Essentially, it's the pathway of mandibular movement created by the contours of the teeth. This means we can place teeth in different locations and it will dictate how the patient closes and moves.

"Neuromuscular" Envelope of Function: This is the mandibular movement created by the patients own neuromuscular movement pattern. This is essentially the dynamic relationship determined by the patient.

KEY: Our goal as clinicians is that we want the "dental" envelope of function (where we put the teeth) to be in harmony with the patient's "neuromuscular" envelope of function (where they want to move).



Comments

Commenter's Profile Image Lawrence Gottesman, DDS
July 2nd, 2013
Gregg: This is a very interesting comment. Please explain how you will know if the patient's neuromuscular or sensorimotor goals match the input created by the newly made dental component (as dental restorations). Secondly, you also talk about the dental envelope of function as static and then move right into creating dynamic movement within the same definition. I hope you can provide some clarity within this space. Thanks, Larry
Commenter's Profile Image Gregg Kinzer
July 8th, 2013
Dr Gottesman, Thank you for your question. In order to know if the patient’s neuromuscular or sensorimotor goals (neuromuscular envelope of function) match the input created by the newly made dental component (dental envelope of function) we need to perform what we'll call "trial therapy". Essentially, using composite or placing provisionals in the patient with the new shape and/or tooth position, allow the patient to live with the interim restorative treatment for a certain amount of time, and then re-evaluate the trial therapy. For example, if provisionals were placed (thereby changing the dental envelope of function) I would be looking at the provisionals for signs of wear / fracture or if the provisionals became un-cemented during the time of the trial therapy. If after evaluating the trial therapy I saw no problems in the provisional phase, I would assume that the new restorations sit within the patient's movement pattern (their neuromuscular envelope of function) and proceed to definitive therapy. If however, problems were seen during the trial therapy, I would evaluate the mode of failure and make the appropriate changes in the provisionals prior to continuing the trial therapy.
Commenter's Profile Image Jack Felton
July 12th, 2013
Dear Greg, I have an interesting case an would like your input.I like the idea of evaluating the temps over time but what if you don't have that luxury. Let me explain my pat has her daughter's wedding next sat we. Preped her for 6 veneers tuesday she broke all of them off by thursday we repreped and took new impresion thursday and she broke # 8 off today I know she has a pathway problem I added 2 mm to her incisal edge postion she did have ortho to improve her overbite I have shorten the length that I want for her incisal edge postion should I also shorten her lower inciors to allow her to get within her envelope of function. I don't have the luxury of time to trial run this thanks for any help you can offer. Jack from toledo ohio we still want to get your family to put-in-bay
Commenter's Profile Image Dr.aditi Patel
May 16th, 2015
Thanks for giving good knowledge