Rua Marquês da Fronteira Nº 4B 1070-295 Lisboa, Lisboa

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Treatments

Occlusion and bruxism

What is Occlusion?

Occlusion is the area of dentistry that deals with the relationship between the upper dental arch (maxilla) and the lower arch (mandible) and their connections to the surrounding structures (teeth, gums, bones, muscles, ligaments, temporomandibular joint). In a physiological occlusion, there should be a harmonious relationship between the maxilla and mandible, without interferences or premature contacts (caused by poor tooth positioning, among other factors), where the mandibular condyle is properly positioned in relation to the glenoid fossa (temporomandibular joint).

Occlusion refers to any contact between the upper and lower teeth. However, this definition is only complete when considering the dynamic, morphological, and functional relationship between all the components of the masticatory system: the teeth, the supporting structures of the teeth, the neuromuscular system, the temporomandibular joints, and the craniofacial skeleton.

We have experienced dentists with extensive technical and academic knowledge in diagnosing and treating functional occlusion imbalances. Most imbalances manifest as pain in the temporomandibular joint, ear pain, headaches, difficulty and limitations in jaw movements, and in extreme cases, jaw locking, making it impossible to close the mouth.

What is Temporomandibular Dysfunction?

Temporomandibular Dysfunction (TMD) and orofacial pain are pathological conditions of the temporomandibular joint (TMJ) that can cause pain in the facial structures, associated with dysfunction.

TMDs are pathological changes related to the temporomandibular joint (TMJ), which connects the skull and the jaw. These dysfunctions can involve the masticatory muscles, ligaments, and nerves in the buccal-facial or cervical regions.

The consequences can include headaches or neck pain, ear pain, joint noises (clicking), ear ringing, limited mouth opening, tooth wear, and difficulties in chewing.

The exact cause is still not fully defined, but it is believed to be multifactorial. Stress is considered the primary trigger for TMD, in addition to parafunctional habits such as bruxism, head and neck trauma, poor posture, and malocclusion.

What is bruxism?

Currently, bruxism is defined in two ways:

  • Nocturnal bruxism consists of hyperactivity of the masticatory muscles during sleep, characterized by both rhythmic (phasic) and non-rhythmic (tonic) phases. In healthy individuals, it cannot be considered a sleep disorder or a movement disorder.
  • Diurnal bruxism refers to hyperactivity of the masticatory muscles while awake, characterized by repeated and sustained tooth contacts and/or rigid jaw contraction in a fixed position or abrupt jaw movements, with or without tooth contact. In healthy individuals, it cannot be considered a movement disorder.

In most people, bruxism is not a pathology, but in some patients, it may be a sign of another condition, such as obstructive sleep apnea, epilepsy, etc.

Additionally, bruxism should primarily be considered a risk factor rather than a pathology. It is multifactorial in origin and a significant risk factor, as it can have negative consequences on oral health, such as tooth wear, fractures, and temporomandibular joint (TMJ) disorders.

Bruxism can be summarized as follows, depending on the patient and their clinical situation:

  • Bruxism as a harmless behavior.
  • An increased risk factor for other clinical situations, with clinical consequences that need to be addressed.
  • A protective factor for general health, as it may serve as a way to release accumulated emotional stress or as a defense mechanism in patients with sleep apnea.

Frequently Asked Questions

Recent studies show that between 15% and 90% of the population has experienced episodes of bruxism, but only between 5% and 20% are aware of it. Nocturnal bruxism is difficult for the patient to identify since it is an unconscious parafunction. It is usually only when significant tooth wear or complaints of orofacial pain occur that the patient seeks help.

Sometimes, it is identified by others due to the noise the patient makes when grinding their teeth. Both adults and children can experience bruxism at some point in their lives. In children, recent studies associate nocturnal bruxism, which is currently classified as a sleep disorder, with obstructive sleep apnea syndrome, requiring special attention from the physician.

Bruxism is related to the central nervous system. Emotional stress and anxiety accumulated throughout the day are released in the masticatory muscles, leading to increased muscle contraction and, consequently, teeth grinding or clenching. This does not occur continuously but in peaks or in a fluctuating manner, alternating with quieter phases.

The consequences of bruxism include tooth wear, occasional fractures of teeth, restorations, crowns, and even implants. Another consequence is the wear of the temporomandibular joint (TMJ), which can trigger, if there are additional factors, a temporomandibular disorder (TMD) with orofacial pain.

A veneer, under ideal conditions, should last between 10 and 15 years, with the possibility of lasting longer if there is good oral hygiene and a favorable occlusion (bite).

Yes, it is possible to restore worn teeth through crowns, direct restorations with composite resins, or indirect ceramic restorations (onlays or overlays). The goal of this rehabilitation is to restore aesthetics, balance, shape, and function.

Bruxism splints are custom-made acrylic plates designed to prevent contact between the upper and lower teeth. Since the acrylic is softer than tooth enamel, it is the splint that experiences wear, not the teeth.

When the splints are delivered, adjustments are necessary, and over time, the dentist should check if further adjustments are needed. The splint should not be worn continuously, but only during critical periods of bruxism, which the patient can start to identify with time and practice.

Professionals in the field