Neuro Occlusal Rehabilitation RNO
– Introduction :
The development of the individual is dependent on its genome and the paratypical stimuli of the functions and the environment which surrounds it.
While intervention at the genome level is still impossible today, we can influence the stimuli, and if necessary modify them. The phenotype of an individual will be the result of the combination of genotypic function and paratypic stimuli.
1-Definition :
The face grows thanks to the development of the nasal cavities and the masticatory system. This part of the body requires a lot of paratypical stimuli to develop. However, our modern cuisine based on baby bottles, porridge, croquettes and other hamburgers no longer produces the stimuli necessary for the harmonious development of our teeth.
PLANAS concludes that : “all the problems of our stomatognathic system, with rare exceptions, are caused by functional masticatory impotence caused by the insufficiency of mechanical constraints generated by our civilized diet.”
The therapy will therefore consist of rehabilitating the mastication function alone to produce sufficient nervous excitations to trigger a developmental response.
He invented Neuro-Occlusal Rehabilitation: What is NOR?
“It is the restoration of the physiology of the masticatory system.” (Jacqueline KOLF)
2- Law of minimum height
Thus, he observed that the minimum vertical dimension corresponds to the maximum intercuspation occlusion, that is to say to the functional occlusion, the one to which the masticatory cycles lead, the one that is used for swallowing. Any lateral or anterior excursion will systematically result in an increase in the vertical dimension.
He called this constant the “Law of Minimum Vertical Dimension.”
Neuro Occlusal Rehabilitation RNO
3. The Functional Masticatory Angles of PLANAS (the AFMP)
Starting from the maximum intercuspation position, the AFMP is the angle formed, in the frontal plane, by the horizontal and the line, more or less oblique, materializing the displacement of the lower inter-incisal point during a mandibular lateral movement.
Neuro Occlusal Rehabilitation RNO
What do we observe?
First of all, it is not easy for all our patients to perform these movements, even though they are physiological; some will have great difficulty and we will be obliged to help some of them.
Others will slide easily on one side but will have great difficulty sliding on the other side.
Others will systematically start from the same side, right or left, when we ask them to perform lateral movements.
3.1. The right and left AFMPs are equal.
After a few minutes of practice we will be able to achieve these lateral movements both to the right and to the left.
If we break down these movements using the slides, we see
First of all, this patient is in class I canine and molar on the right and left and that there is perfect correspondence of the upper and lower inter-incisor centers.
During the lateral movement to the right, there are working contacts but also non-working contacts and incisal contacts.
Similarly, during the left lateral movement, there are also working contacts, non-working contacts and incisal contacts.
If we look at the AFMPs we see that they are equal.
We can conclude that:
If the chewing is physiological, in other words unilateral alternating, the right and left AFMPs are equal, and vice versa: if the right and left AFMPs are equal, the chewing is physiological of the unilateral alternating type.
3.2. The right and left AFMPs are unequal.
If the right and left AFMPs are unequal, chewing will be pathological, and conversely if chewing is pathological the right and left AFMPs will be unequal.
Here is the example of François who is completely unbalanced:
The left AFMP is smaller than the right AFMP.
Neuro Occlusal Rehabilitation RNO
If we detail this using the slides, we first see:
That it is in Class I canine and molar on the right but that it is in Class II on the left, there is no correspondence between the upper and lower inter- incisal midpoints and we observe a deviation of the lower inter-incisal point towards the left.
If we examine the AFMPs we can clearly see that the left AFMP is smaller than the right AFMP.
Chewing is always done on the side where the AFMP is smaller .
You see that the left side is smaller than the right side.
3.3 Evolution of AFMPs according to age.
It should also be noted that these AFMPs will change depending on age.
Even if they are equal, the AFMPs will not have the same value at 3 years, 5 years, 13 years or 60 years. This is the consequence of tooth wear:
Neuro Occlusal Rehabilitation RNO
4. Open-close chewing.
Walter’s mastication movements, which are used to chew soft foods , will not create the stimuli necessary for normal development of the stomatognathic system. The result will be retromandibulia, DDM, deep supraclusion, biretroalveoli. Lateral movements will be very difficult to perform and the AFMP will be very vertical.
5. Unilateral Dominant Chewing Syndrome:
Often this syndrome goes completely unnoticed, especially in young people. In fact, since chewing is automatic and food becomes less and less consistent, the patient rarely notices that he is chewing on only one side.
However, this dominant unilateral chewing will have consequences on the growth of the jaws and will also, in the long term, have consequences on health.
6. The different therapies used in RNO:
The stomatognathic system must be given the stimuli necessary for harmonious development and as early as possible. Never wait, Pedro PLANAS constantly repeated.
6-1 In children:
– Encourage breastfeeding until the age of 1 year or at least until the incisors appear .
– Favor a more consistent diet for young children.
– Selective grinding: This is the reasoned wear of the baby teeth as it would have happened if the child had always chewed in an alternating unilateral manner.
Around 2 or 3 years of age, the distal slopes of the lower canines can be ground down in occlusion without affecting the vertical dimension , then, laterally, the enamel can be removed from the mesial edge of the upper canines to make the AFMPs smaller and improve masticatory function.
Grinding, by equalizing the AFMP, will allow the establishment of alternate unilateral chewing.
– Direct tracks are resin applications bonded to the baby teeth to correct a reversed lateral bite or increase an AFMP to make it non-working.
– Indirect tracks or track plates, which are not ordinary jack plates but functional devices directly inspired by the physiology of mastication, will allow the expansion of the jaws and the installation of a plane
physiological occlusal. (Fig.20)
– The equiplan will correct overbites.
In adults
The same therapies can be used but the results will take longer to obtain and are more likely to recur.
Grinding will be used but with caution. As Planas said: “A well-done selective grinding, for example at two years old, can save a mouth for life” but he added: “A poorly done selective grinding is more harmful than no treatment at all.”
In the event of occlusal imbalance, it will first be necessary to look for and eliminate the double occlusion and then check and equalize the AFMPs.
For more complex cases, a fixed or mobile prosthesis will need to be added in order to restore a balanced occlusal plane, which is the only way to restore physiological chewing to disturbed patients.
Conclusion
To sum up, PLANAS used to say, in a figurative way, “that a dentition that only works with opening-closing movements in centric occlusion is like an individual who walks by jumping with both feet together. A dentition that works unilaterally is like an individual who walks by hopping. But if the dentition works alternately in a balanced way on the right and on the left, it is like the individual who walks with both feet, one after the other. The two compensate each other and each depends on the other, they make the same effort for identical times.”
This is the function that we must offer to our patients. For this, we must obtain, as early as possible, occlusal balance through alternate unilateral chewing and maintain this balance throughout life.