49.) DIAGNOSIS AND TREATMENT OF THE OPEN BITE
What do we mean when we talk about patients with a malocclusion called open bite?
Generally spoken this definition includes all patients whose upper teeth will not occlude with all their lower teeth .Even if only two teeth will not occlude the definition open bite is being justified .
By having this in mind we can differentiate between a lateral open bite on one side or the other or on even both sides or a frontal open bite which occurs more often. When we talk about the open bite , we have to discuss three different origins because each of the three different groups has to be related to a specific treatment :
1. The first group includes all open bite patients who have developed this malocclusion by means of exogenous influences, by habits just like extensive use of pacifiers, by thumb-sucking, or a tongue-thrust after the open bite has been established. Because of their tongue thrust they often have problems in pronunciation in the way of a more less strong lisp.
2. The second group can be described as a patients who are mainly mouth-breathers. When we watch them entering the practice, they often have their mouth open , their muscle tension seems to be weaker than others their lips are dry sometimes even infected because of their permanent licking them and their mothers report of ear-problems, infected tonsils and often occurring colds. Some of these kids have allergies against dust, plants or animals like horses, dogs or cats. Most of them complain about enlarged adenoids .
Mouth breathing also means a wrong position of the tongue in the lower jaw instead on top of the maxilla. The pressure of the cheeks from the outside and the lack of pressure from the inside often create a lateral cross-bite in combination with a frontal open bite.
These two groups include patient with a dental open bite .
Naturally never often we meet a mixture out of both grous, which however does not influence the way of treatment. This differs generally to the treatment of the third group:
3. The skeletal open bite: patients showing this malocclusion as weññ often appear their lips not being closed. If they want to achieve closed lips , the tension of the chin muscles id visible. They are mouth breathers and they have a tongue thrust but all this is the result of their malocclusion and not the reason for it .A malocclusion which is inherited and it can mainly be diagnosed on other children or young adults One very specific skeletal open bite has to be mentioned as well. It is caused by the lack of vitamin D not sufficiently supplied with in the first years after birth. A disease known as Rachitis. Because of good nursing and well balanced diet this disease is very seldomly met. Before we discuss manners of treatment we first have to establish a correct diagnosis.
This is not very difficult when a young child comes into our office showing the above described appearance: mouth open, dry lips, weak tonus. We will have a lock of this thumbs first and will see that at least one of them appears much cleaner than the other .(The tongue is a perfect thumb cleaner). This child cannot really bite off thin food because his front teeth do not touch. He rather tears the bread off with his morals. All the chewing work is accomplished only by eight or twelve morals which often show extensive abrasions.
The clinical investigation on this patient is sufficient for our diagnosis : Frontal open bite caused by thumb sucking. This however does not mean that we insert an orthodontic treatment appliance when we agree to start correcting the position of the maloccluding teeth. The first step of treatment is to abolish the reason for the malocclusion rather than to try to work against the symptoms .
Nevertheless e advise the mother to consult a neck and throat specialist concerning the tonsils and the adenoids.
In case they are enlarged or more than once a year infected they have to be removed. Beside this we often have to recommend a logopedits to train the speech, a physiotherapist to strengthen week muscles and myofunctional therapist to harmonise the orofacial muscles. In case such specialists are not available we have to fulfil a training program in our office : After we have secured some success in above mentioned pre-treatment therapy we can start constructing the best suiting appliance for our patient based on our exact diagnosis: We need to do impressions, photos like frontal and lateral views and a frontal smiling patient as well as panoramic and a lateral long distance X-ray. When our patient gets close to puberty an X-ray of the palm can tell us about the expexted growth potency. All these devices have to be evaluated and the measurements lead us our final diagnosis. Based upon that we will establish our treatment plan including our treatment appliances and report it to the parents.
All above mentioned treatment devices only work on growing patients. Once the patient is grown up we have to alter our treatment plans completely. To find out about this we should X-ray the palm or if this is not accepted or not possible we have to ask about the increase of height in the last six month. In case there is no further increase we are confronted with an adult.
On Adult open bite patients only surgical intervention is successful. Before surgery can be undertaken we as orthodontists have to decide where cuts have to be made, whether the osteotomy has to be done on the mandibular only or a bimaxilary osteotomy is recommendable.
Asociación Mexicana de Ortopedia Maxilar, A.C.
AMOM 2015 © ® diseño web: www.veronicataboada.mx