Occlusion : neglected and abused ….?

In our clinical practice, we routinely encounter patients with excessive occlusal wear, craze lines, cervical abfractions, spacing between teeth, loose teeth and blindly resort to placing restorations, crowns, prosthesis, implants and so on without even bothering to find out the root cause of the disease process. It is like arbitrarily treating the signs and the symptoms of a disease without tackling the etiology. A clear understanding the principles of occlusion will bring about a dramatic change in the way these cases are approached.

Occlusion is of primordial importance for the successful practice of dentistry since all treatments carried out in practice whether it be restorations, replacements, orthodontic teeth movements or any other, are all planned and designed to fit harmoniously with the complexities of the neuromuscular control system, the temporomandibular joints and supporting structures of the teeth without introducing occlusal interferences.¹

‘Occlusion’in simple terms, refers to the arrangement of maxillary and mandibular teeth and to the way in which they contact. The study of occlusion involves not only the static relationship of teeth but also their functional interrelationship and all components of the masticatory system. A harmoniously functioning occlusion allows for smooth uninterrupted movements over the area of tooth contact. Some occlusions may not permit such free movements, yet the patient do not exhibit any problems, owing to the neuromuscular adaptation to the disharmony. However, if it exceeds, the adaptive capacity of the system it leads to signs and symptoms. Every treatment starting from simple filling to complex crown and bridgework, implant prosthesis can affect occlusion. Therefore, they have to be planned in such a way that they do not cause effects that exceed the adaptive tolerance.²

Successful occlusal management leads to predictable restorations and prostheses, longevity and absence of iatrogenic problems, patient comfort and occlusal stability. Occlusal forces will primarily dictate the selection of type of restoration, the material selection and even the design features needed for a successful outcome.

It is very unfortunate that the occlusion of teeth is frequently overlooked or taken for granted by most dental practitioners. This may be because in most cases, symptoms of occlusal disease are often not very obvious and patient may not even complain. Secondly, the practitioner is not trained enough to recognize them or to appreciate their significance. Dental colleges spend hardly any time teaching occlusal concepts, leaving a huge gap in our knowledge base of this crucial and most relevant topic. Added to it, occlusion is perhaps one of the most controversial subjects in dentistry often making it appear more complicated than it really is. There is a lack of an unified theory on how to evaluate an occlusion and treat occlusal problems. However, consensus seems to have emerged on the following basic principles.

• The teeth should have bilateral and even occlusal contact throughout that allows for proper load distribution and a stable occlusion. When a tooth interferes with full closure, it will trigger deflective interferences.^3-5

• Anterior and canine guidance allows for immediate disocclusion of molars and premolars when making lateral or protrusive movements, such as in chewing. This immediate posterior disocclusion provides some important mechanical benefits in that masticatory muscles significantly decrease the amount of force applied to the anterior guiding teeth .

• All the teeth should fit within the confines of the muscle forces for the best stability.

• Should provide an unobstructed envelope of function.

• Functional movements should allow for access to maximum intercuspation without interferences occurring in the posterior or anterior teeth. Eliminating interferences is important.^6,7

Failure to embrace sound occlusal principles will result in failure of restoration, prosthesis, or periodontal treatment along with relapse of orthodontic and orthognathic surgeries. It is crucial to recognise the signs of occlusal disease in the early stages, to arrest progression and prevent further damage.⁸

Diagnosis and Treatment of occlusal disease is vital to dentistry. Every patient needs an occlusal evaluation initially as part of a comprehensive examination. The criteria for diagnosing occlusal problems and the indications for treatment are based on an assessment of the health and function of each individual’s masticatory system. The implication is that individuals do not necessarily fit into a prescribed occlusal concept but that each occlusion should be considered separately and treatment needs to be tailored to individual requirements. It is also important to evaluate the severity of the disease based on signs and symptoms to work on the treatment strategy. Many dentists have an erroneous idea that extensive rehabilitation is the best way of managing occlusal problems. Occlusal management should be minimally invasive based on the severity of the condition and needless to mention that achieving a stable occlusion requires often a multidisciplinary approach.⁹

Conclusion : Understanding the importance of occlusion is the crux in the practice of dentistry. Undiagnosed occlusal problems are responsible for many catastrophic treatment decisions and results.

Early diagnosis and minimally invasive management improves the quality of dentistry and permits patients have a more satisfying, healthier dental life. If we learn to provide a physiological and mechanically sound occlusion, it is of great service to our patients, and a greater asset to clinical dentists. Remember occlusion is central to our treatment decision and patient satisfaction. Never neglect this vital fact.