Chewing, in some cases, can lead to discomfort and pain. And not always the problem is limited to the oral cavity.
Chewing is the first step of digestion: it begins in the mouth, and involves different structures. The food is kept (by the muscles of the cheeks and the tongue) between the teeth, where it is broken up and shredded thanks to the opening and closing movements of the temporomandibular joint, operated by the masticatory muscles. The saliva, thanks to the enzymes contained in it, begins its degradation and the tongue creates a sort of “dough” that then, through swallowing, is sent to the stomach where the digestive process continues.
Precisely in consideration of the complexity and the numerous structures involved in the chewing act, it is easy to understand how multiple factors can hinder it, determining specific disorders.
“The term “chewing disorder” indicates a difficulty in shredding food; often, however, all those disorders related to a malocclusion, that is, an incorrect dental occlusion, are also considered as such» explains Tullio Toti, Clinical Gnathology Manager of the Smart Dental Clinic of the San Donato Hospital Group and Medical Director of the Dentistry Unit of the San Carlo Clinic in Paderno Dugnano (Milan).
«When occlusion comes into play, that is the way in which the teeth come into contact, it would be more correct to speak of swallowing disorders, because when you chew the teeth do not actually touch, because of the interposition of food; The contact between the teeth occurs instead when swallowing, even just saliva, a movement that we perform on average once a minute, automatically even during sleep» underlines the specialist.
Having made this clarification, let’s see, therefore, the main types of masticatory disorders in relation, in particular, to the causes that determine them.
Chewing disorders: what can be the causes?
“The disorders may be due to intraoral causes, i.e. inherent in the mouth, or they may depend on factors external to it (extraoral)” anticipates Toti.
Intraoral factors include a disorder in the distribution of teeth, caused by:
- the lack of one or more dental elements, perhaps following an extraction without a subsequent implant intervention, or as a result of a disease such as periodontitis, not adequately treated
- a wrong prosthesis, for example too high on one side
- a non-ideal alignment of the final teeth, not corrected by orthodontic interventions.
Obviously, even if the teeth are distributed correctly and all of them are there, the presence of dental problems (caries, pulpitis, hypersensitivity, etc.) and / or gums (periodontitis), can still interfere causing pain when chewing.
Even an incorrect positioning of the tongue inside the oral cavity, for example because it is too large compared to the mouth or, on the contrary, too small or for dysfunctional movements resulting from bad habits, can cause a malocclusion, hindering swallowing and chewing.
There may also be an imbalance, in shape and / or size, between the mandible and the maxilla, the two bones of the skull that house the dental arches (the lower jaw, while the jaw the upper one): consequently, for example, one arch can be in an advanced position with respect to the other and therefore prevent the teeth from touching each other correctly. Or, a bone base may be too small and consequently there is an “overcrowding” of the dental elements which, not finding enough space, grow in a crooked and disordered way.
“An imbalance between the bone bases can also have extraoral causes and be connected, in particular, to alterations in postural development,” underlines Toti.
The assumption of correct postures, stationary or moving, depends on the neuromuscular system: the brain, once received specific signals from the outside, processes them and transforms them into commands that send, through the nervous system, to the muscles in order to assume a certain posture. These signals come, for example, from the feet, from the ear, from the eyes, but also from the jaw; In fact, there is a close connection between the cranio-mandibular system (also called stomatognathic) and the rest of the skeleton and other muscular systems.
“Problems of support of the feet, such as a flat foot or a hollow foot, can therefore determine posture attitudes that, especially in the growth phase, can induce the masticatory system to a malocclusion” exemplifies the specialist. “In the same way, even an incorrect synergy of the muscles that control eye movement (as in the case of heterophoria, also called latent strabismus) can end up negatively affecting chewing.”
Among the factors that can negatively affect chewing, but not really internal to the mouth, it should also be remembered bruxism, a condition, generally attributed to psychological factors, which leads to grinding and / or tightly clenching the teeth during sleep; The first and most direct consequence of pressure and grinding are the deterioration and wear of the dental elements, which are also associated with a tension of the masticatory muscles and a stress on the temporomandibular joint.
Moreover, the pain during chewing can depend substantially on any disorder affecting the temporomandibular joint, including forms of osteoarthritis. Not only that: since the masticatory muscles are innervated by the trigeminal (the fifth cranial nerve, which innervates the face), even an inflammation of the same can determine the appearance of severe pain while chewing, as well as the presence of diseases affecting the salivary glands (such as stones or tumors).
Finally, among the extraoral pathologies that can also cause masticatory symptoms, Horton’s giant cell arteritis, a vasculitis that affects in particular the large arteries of the head and neck, especially the temporal ones, which supply blood to the jaw muscles: those affected, in addition to feeling a strong headache, can develop the so-called masticatory claudication , with pain and fatigue in the jaw when chewing.
Consequences of bad chewing
Pain and difficulty chewing lead, first of all, to poor digestion, associated with other gastrointestinal symptoms, from aerophagia to meteorism, for example. The food, in fact, is not carefully shredded and, therefore, increases the amount of air ingested with it.
And that’s not all. Abnormally stressed chewing muscles become inflamed, resulting in a painful sensation while eating at the level of cheeks, temples, forehead and around the ear (dizziness and tinnitus may also be felt). The pain, through a sort of chain reaction called “descending syndrome”, also radiates to the muscles of the neck and shoulders, causing muscle-tension headaches and cervicalgia, reaching, sometimes, even the lumbar part of the back.
If temporomandibular joint disorders can affect chewing, the opposite is also true: with occlusion problems the joint becomes destabilized, inflamed, you may experience noises and “clicks” when chewing and, if the articular ligaments are particularly yielding, you also risk a possible dislocation and blockage of the jaw.
As we have already had the opportunity to say, moreover, the stomatognathic system is connected to the postural system and, if it is true that wrong postural attitudes can negatively affect occlusion and chewing, vice versa, even masticatory / swallowing disorders due to intraoral causes, in the long run, if not corrected can negatively affect posture.
Chewing disorders in children
Chewing is a skill that is acquired gradually in the very first years of the child’s life, generally starting from 6 months (a period in which on average the first milk teeth begin to appear) up to six years, and is also fundamental for the definition of the structure of the mouth, as it favors the development of the muscles of the face and allows the harmonious growth of the bones of the skull.
The type of feeding and also the presence of some attitudes (thumb sucking, use bottles and pacifiers for a long time) can, however, interfere with proper chewing learning and translate, over time, into real occlusal disorders.
“Today in children there is a generally decreased chewing activity, because compared to the past we tend to give them foods with a softer consistency, which do not require prolonged chewing, so much so that often milk teeth are “new” or in any case little worn when they are replaced by definitive. But if you chew little, the stomatognathic system is not stimulated and therefore does not develop completely: the palate, for example, does not enlarge sufficiently and this can determine over time a discrepancy between the bone bases and therefore a malocclusion » explains the specialist.
The habit of pushing the tongue against the teeth is also harmful. If, in fact, it is normal for infants to swallow by pushing the tongue forward, when the baby grows, this should be placed in a point just behind the palate (palatine spot). If this does not happen (we speak of atypical swallowing), the tongue, pressing against the teeth, interferes with their growth and their correct alignment, hindering chewing, but also favoring language disorders due to incorrect phonation, or the articulation of sounds, which depends precisely on the different attitudes assumed by the tongue, as well as by the lips and the soft palate.
A visit to the dentist specialized in gnathology (the branch of dentistry that deals with the study and care of the stomatognathic system and the functions it performs), in preschool age, can therefore also be useful with a view to prevention. Not only because a masticatory problem, by virtue of the connection between the stomatognathic system and the rest of the skeleton, could also have postural repercussions (the meeting between the teeth in the occlusion stops the jaw and allows its positioning in relation to the skull) but also because, precisely in childhood, alterations of postural development begin to occur (flat or hollow feet or heterophoria) which, As seen, extraoral causes of chewing disorders are possible.
How the diagnosis is made
The doctor of reference for chewing disorders is the dentist specialist in gnathology who often works in teams with other specialists (for example the physiatrist, the orthoptist, the speech therapist etc.).
“The visit cannot be separated from an in-depth interview with the patient, the collection of anamnesis and evaluation of symptoms, which can be very different from case to case,” explains Toti. “Therefore, before observing the inside of the mouth it is always advisable to proceed with postural tests, to detect the anthropometric data of the posture and re-evaluate them after having “excluded” the dental arches from the system (Meersseman test): the comparison of the results of these surveys allows us to understand if there is a postural problem and if it is connected or not to dental occlusion. In order to detect any imbalances, the stabilometric platform is also used, an electronic instrument that allows various measurements to be performed that can indicate whether or not there is the presence of neuromuscular problems, with consequent postural adaptation of compensation».
The mouth is then examined, checking how and how much it opens and the state of the teeth and generally also performing radiographs of the temporomandibular joint. “You can also use CT scan or an MRI, with the mouth closed and in maximum opening, the first to check the bone structures, the second to evaluate the soft parts. Often, moreover, an electromyography is performed, to evaluate the functionality of the masticatory muscles and the degree of tension» adds the expert.
Possible solutions
The therapy of chewing disorders is obviously linked to the triggering causes. If there is an extraoral factor, for example a problem of plantar support, it will be up to the physiatrist or orthopedist to develop a specific treatment, for example by resorting to physiotherapy and specific exercises / or the use of special orthotics.
“At the level of the mouth, interventions can be very different depending on the causes of the chewing disorder,” explains the specialist. «To rebalance the relationships between the arches and / or in the presence of joint disorders, for example, we generally intervene with a custom-made bite, that is to say a sort of resin plate to be worn, generally on a single arch, for a few months (in some cases 24 hours a day, in others only at night)».
If the dental elements need to be straightened, specific orthodontic appliances can be worn, fixed or mobile (functional). It may also be necessary to resort to oral surgery (if, for example, it is necessary to remove a wisdom tooth that fails to sprout correctly and in doing so triggers muscular defense reactions) and implantology to remedy missing elements or incorrect prostheses.
Finally, dental and/or gum problems may require endodontics (treatment of diseases affecting the root and internal pulp of the tooth) or periodontology (the treatment of problems affecting the periodontium, the set of tissues surrounding the teeth).
Joycelyn Elders is the author and creator of EmpowerEssence, a health and wellness blog. Elders is a respected public health advocate and pediatrician dedicated to promoting general health and well-being.
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