Abstract
The role of occlusion in the progression of periodontal disease remains a controversial subject. Occlusal force, which is a mechanical stress applied to tissues, has always been considered to not initiate, nor accelerate, periodontal attachment loss resultant from inflammatory periodontal disease. This chapter outlines this controversy in great detail, from the perspective that the absence of a validated occlusal force and timing measuring device that can quantify the occlusion, has contributed to the confusion and questions that exist in the scientific community about the relationship between both periodontal disease and peri-implantitis, and the occlusion. The development of a new occlusal measurement technology that records and analyzes precise and reproducible relative occlusal contact force levels in real-time, independent of a clinician's subjectivity, is helping to change the scientific opinion regarding occlusion's role in periodontal and peri-implant supporting tissue loss. The T-Scan 10 system is particularly adapted for treating patients who demonstrate tissue loss combined with occlusal issues. Indeed, after having controlled the major etiologic and risk factors of periodontal disease and peri-implantitis, adjusting the occlusion after active tissue and implant therapy favors healing. The outcome of periodontal treatment aimed at compromised teeth and dental implants, combined with occlusal force excess control from computer-guided targeted occlusal adjustments, is highly predictable, and is characterized by less inflammation, a decrease of probing depths, and the stabilization of bone levels around teeth and dental implants.
TopIntroduction
The Periodontium is characterized by several tissues:
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Soft tissues, such as the keratinized gingiva
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The free gingiva
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The periodontal ligament (PDL)
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The hard tissues around the teeth such as bone and cementum.
Periodontal diseases are multifactorial and considered to be of bacterial origin, which are characterized by the presence of gingival pockets and progressive loss of attachment with bone resorption occurring around teeth. It is possible to ensure the periodontal health of the patient by keeping these pockets shallow. Clinicians are therefore perpetually faced with the need for probing pocket depths of any detected periodontal pockets.
Clinicians also check for two groups of potential Periodontal disease risk factors, which include:
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Innate human factors (age, sex, ethnicity, genetic predisposition)
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Acquired factors (microbiological factors, smoking, and other systemic disease states)
The link between occlusion and impaired periodontal health has always been a matter of great debate (Green & Levine, 1996). However, occlusion is not generally considered to be a risk factor for periodontal disease, but is rather viewed as an aggravating factor in the same was as is tobacco use. Despite that in everyday practice, clinicians observe obvious links between occlusion and periodontal parameters, the absence of an “evidence based” occlusal force analysis makes difficult the demonstration of these interrelations. The T-Scan III, could help to address unanswered questions. The aim of this chapter is to review how occlusal analysis can be integrated in periodontal treatment and how a computerized occlusal analysis can help the clinician in his practice.
TopBackground
Interrelations between periodontal disease and occlusal forces have been usually defined by the term occlusal trauma. Stillman was the first to define occlusal trauma, as “a traumatic state of the tissues supporting the teeth resulting from the movement of the jaws towards the closed position” (Stillman, 1917). In 1978, the World Health Organization (WHO) defined occlusal trauma as a “periodontal traumatism caused by stress on the teeth induced directly or indirectly by the teeth present in the other arch” (Lindhe, Karring, & Lang, 2008). The American Academy of Periodontology (AAP) defined reduced tissue support, the tooth’s center of rotation translates more apically, which creates a major lever-arm resultant from the occlusal loading (Figure 2). Occlusal trauma as “damage to the dental support tissues caused by an excessive occlusal load” (Gher, 1996). There are 2 classifications of periodontal damage resultant from occlusal trauma:
With patients who demonstrate the differing periodontal risk factors, secondary occlusal trauma makes treatment more difficult because the compromised teeth are often embedded in a damaged periodontium. With reduced bone support, when force is applied to the crown of a tooth that has
Figure 1. Primary occlusal trauma results from excessive occlusal force with a normal support. The center of rotation is near the middle of the tooth.
Figure 2. Secondary occlusal trauma results when excessive occlusal force is applied to a tooth with reduced support. The center of rotation moves down into the apical third of the root.
Key Terms in this Chapter
Periodontal Maintenance Therapy: Following active periodontal therapy, maintenance is necessary to preserve the results obtained during the active therapy, and to prevent further periodontal disease breakdown. Maintenance is an extension of active periodontal therapy, requiring the combined efforts of both the periodontist and the patient.
Complete Digital Workflow Including the T-Scan System: A 10 step process that increases the accuracy of placing implants with the correct vertical axis, establishes the correct distribution of occlusal forces around implants, and helps reduce the learning curve of placing implants within the esthetic zone, When the T-Scan functional occlusal force and timing data is added into the rehabilitative process of the complete digital workflow, the term should be revised and become “The Dynamic Digital Workflow (DDW).”
Full Mouth Disinfection: An intense course of treatment for periodontitis, typically involving scaling and root planning in combination with adjunctive use of local antimicrobial, such as chlorhexidine, applied to the diseased tissues by various intraoral methods. The aim of this therapy s to complete debridement of all periodontal pocket areas within a very short time frame (in 24 hours), to minimize the chance of re-infection of any pocketing from pathogens that reside in other oral niches like the tongue, tonsils, and non-treated periodontal pockets.
Secondary Occlusal Trauma: Occlusal trauma observed that is applied to a tooth with reduced periodontal bone height.
Periodontal Attachment Loss: The reduction in the connective tissue attachment to both the root of the tooth and to the alveolar bone. It is usually caused by persistent inflammation of the gingival and periodontal tissues, and can be worsened by occlusal trauma.
Occlusal Trauma: Occlusal trauma describes changes in periodontal state due to the applied force of the masticatory muscles.
Jiggling: When an applied constraint to a tooth alternates in two opposite directions (i.e., buccal-lingual or mesial-distal), where the tooth no longer is able to move in a given direction, which is different from the continuous unidirectional force applied by an orthodontic device. Functional (non-constrained) mobility is therefore stronger, and more uncontrolled compared to the mobility induced by orthodontic treatment, which is somewhat controlled.
Primary Occlusal Trauma: Occlusal trauma observed that is applied to a tooth without reduced periodontal bone height.
Periodontal Disease: An inflammatory disease process that affects the soft and hard structures that support the teeth, often caused by local pathogens combined with other contributory risk factors.