Comprehensive Occlusal Concepts in Clinical Practice

Irwin M. Becker

• Publisher: Wiley-Blackwell
• Year: 2011
• ISBN:
  9780470958650
• Edition: 1
• Topic: Medicina
• Subtopic: Odontotecnica

Comprehensive Occlusal Concepts in Clinical Practice aims to provide a clear and thorough guide to the understanding and application of occlusal concepts in the dental practice, enabling dentists to gain a straightforward understanding of widely recognized occlusal principles and practices to engender longevity, predictability, and professional confidence in everyday dental procedures. Comprehensive Occlusal Concepts in Clinical Practice also features a comprehensive review of occlusal and periodontal literature, establishes occlusal principles and practice protocols as routine, and aids in developing the reader's critical ability to know when and when not to perform occlusal therapy. This is a unique book in its scope, thoroughness, and practicality, making occlusal concepts easily understood, yet also demonstrating the specific skills needed to perform the details of a physiologic occlusal scheme.

1

Introduction to Occlusal Disease and Rationale for Occlusal Therapy

Irwin M. Becker, DDS

To understand the reasoning and general purpose of entering into any therapy that may change or modify a patient’s occlusal scheme, it is important to first realize that most signs and symptoms of occlusal causation occur mainly in individuals who demonstrate some degree of parafunctional activity. That is to say, a sign such as attrition rarely occurs from normal mastication (Belser and Hannam, 1985; MacDonald and Hannam, 1984; Moss et al., 1987; Silvestri, Cohen, and Connolly, 1980).

INTRODUCTORY DISCUSSION OF PARAFUNCTIONAL WEAR

Almost no one spends sufficient time with their teeth in contact during normal chewing function to cause observable wear patterns. These common wear patterns come from those times of clenching and or bruxing during either nocturnal or diurnal time frames. The potential etiologies of these activities will be discussed in chapter 2.

Of course, there are exceptions to the statement that parafunctional habits are the overriding, most common cause of signs and symptoms of occlusal disease. Conditions such as iatrogenic changes or dual bites, where a patient holds his or her teeth in a position other than some acquired closing pattern, could be considered additional causes of signs of occlusal disease (Attanasio, 1991; Kampe, 1987).

It is also essential for the modern dental clinician to understand that there exists a clear clinical ability to reduce muscle activity during these parafunctionally destructive times, but no clear evidence exists that the clinician can reduce or stop the actual parafunctional habits. The total body of evidence indicates that by providing a physiologic occlusion, a therapist can realistically reduce the muscle activity during bruxing and clenching. The therapist can greatly reduce the results of a destructive habit, realizing that the habit itself remains; only the muscle activity is reduced (Ash, 2006; Baba, 1991; Geering, 1974).

Most of this text will further explain this basic concept and help the reader develop understanding and learn multiple techniques proven to achieve the physiologic occlusion mentioned above. It is necessary first to master the ability to recognize and then categorize all the potential signs and symptoms that make up any given disease (Lytle, 1990, 2001a, 2001b). As in all scientific methodologies utilized in medical and dental practices, there are accepted protocols. These protocols are summarized by detailed examination, varying diagnostic procedures, and treatment planning opportunities when and where appropriate.

RATIONALE FOR COMPREHENSIVE OCCLUSAL EXAMINATION

Obviously, dental examinations must be comprehensive and thorough. But they must be more than a detailed collection of data. The examination is usually performed after any emergencies or other compelling issues have been addressed. Once the patient’s perceived chief complaints or concerns have been addressed, the doctor-patient relationship is more likely to lead to an engaged patient ready to interact with the dentist during the comprehensive clinical examination.

It should be mentioned at this time that there is evidence that pain is not a reliable indicator of the presence of occlusal disease. Epidemiological studies have consistently shown that in large groups of subjects, those with malocclusion have no more pain than those with more ideal occlusal schemes (Kampe, Hannerz, Strom, 1991; Okeson, 1981; Wadhwa and Kapila, 2008). Many clinicians have observed this phenomenon in their own practices, sometimes observing patients with horrible malocclusions who have almost no symptoms. They present with no complaints of pain or discomfort. When these same patients also have no signs, it is then apparent that they spend very little time in parafunctional activity. This is further rationale for a comprehensive occlusal examination to carefully list any present signs and symptoms, as they are a strong indicator of the history of what has taken place on the dentition.

CATEGORIES OF PARAFUNCTIONAL ACTIVITY

After a comprehensive occlusal examination, the clinician should be able to classify a given patient in one of the three categories outlined in table 1.1 (Lytle 1990, 2001a, 2001b).

Table 1.1. Categories of parafunctional activity.

TYPE 1: Almost No Parafunction	No evidence of wear, mobility, tooth migration, muscle soreness, fractures, cracks, craze lines, or abfractive lesions
TYPE 2: Moderate Parafunction	Evidence of slight wear, mobility, tooth migration, muscle soreness, fractures, cracks, craze lines, or abfractive lesions
TYPE 3: Destructive Parafunction	Evidence of excessive wear, mobility, tooth migration, muscle soreness, fractures, cracks, craze lines, or abfractive lesions

ENGAGING THE PATIENT IN THE COMPREHENSIVE OCCLUSAL EXAM

It must be stated clearly now that it cannot be simply left up to the patient to say whether he or she has a parafunctional habit or not. Consistently, the literature suggests that these activities occur either during sleep or at times of stress (Campillo et al., 2008; Glaros et al., 2000; Kevij, Mehulic, and Dundjer, 2007; Wood, 1987). Either way, the patient is generally not aware of these occurrences. It can become quite instructive and helpful for patients to discover the destructive effects of their own habits as the process of co-discovery occurs.

If the clinician asks open-ended questions for the patient to ponder as the patient is shown the results of heretofore-unrealized habits, the patient may discover the destructive effects during the interactive exam process or realize the relationship after the exam. Commonly, patients realize they have been “chewing up their own dentition.” This discovery helps the patient accept recommended phase I treatment such as occlusal splint therapy.

RATIONALE FOR OCCLUSAL THERAPY

The various signs that are detected during a routine yet thorough occlusal exam are usually repeatable and measurable, and they are the best indicators of occlusal disease. It is appropriate for the comprehensive dentist to perform this type of examination prior to determining the category of parafunction present in the patient’s history and prior to treatment planning. The dentist only has a scientific basis for providing definitive occlusal therapy when the patient has clinical signs of occlusal disease (Clark et al., 1999; Machado et al., 2007; Okamoto et al., 2000; Ratcliff, Becker, and Quinn, 2001; Speck, 1988).

Unless there exists a need to change the acquired occlusion because of orthodontic or restorative requirements, there is little literature-based support for therapies such as occlusal equilibration. Even when signs and symptoms do exist, it is important for the clinician to prove that these signs are directly related to occlusal factors. Only if there is evidence of occlusal instability or parafunction should the clinician attempt to modify the occlusion. When there is no evidence, the clinician should leave the patient with his or her wonderfully adapted and acquired occlusal scheme.

Some discussion is needed at this time about the literature involved with noncarious cervical lesions (Braem, Lambrecht, and Vanherle, 1982; Dejak, Mlotkowski, and Romanowicz, 2005; Grippo, 1991; Grippo and Simring, 1995; Kuroe et al., 2001; Lee and Eakle, 1996; Madani and Ahmadian-Yazdi, 2005; Pegoraro et al., 2005; Pintado et al., 2000; Spranger, 1995; Winter and Allen, 2005). It is common for clinicians to assume that these wedge-shaped lesions have an occlusal traumatic etiology. Even though there exists some conflicting literature, it has yet to be scientifically proven that abfraction solely occurs as a result of occlusal trauma. More likely, it is a result of a multifactorial phenomenon of trauma, lack of buccal bone, prominence of the root, and some tooth brushing and tooth paste abuse. The clinician has little choice but to include all of these possibilities in thinking about what to do with a dentition that has some abfractive lesions. When these lesions are present and there is evidence of occlusal trauma, the clinician should remove occlusal trauma as one of the possible etiologic factors.

If root prominence exists, orthodontics could be helpful. There may be a rationale for gingival grafting to protect the root with attached gingival. This is just one example of the complexity and sophistication needed to accurately define the cause and effect of many so-called multifactorial conditions in dentistry and medicine.

THE COMPREHENSIVE OCCCLUSAL EXAMINATION

A comprehensive occlusal examination must include but not necessarily be limited to the following components:

• Occlusal analysis (described below)
• Muscle palpation (described in chapter 6)
• Range of motion (described below)
• Joint sounds (described below)
• Joint palpation (described below)
• Articulated study casts (described below)
• CR (centric relation) analysis (described below)
• Digital imaging (described below)

Occlusal Analysis

Marking the teeth with appropriate ribbons after drying them with tissue paper folded on a Miller Forceps allows the clinician to identify what parts of the teeth touch during arc of closure as well as excursive movements. These markings indicate which occlusal surfaces can touch during patient instruction but not necessarily what the patient actually does during parafunctional movements. The clinician must look for actual evidence during the rest of the exam to correlate these markings with recordable signs such as wear or mobility. This process can be another learning moment for the patient, when both the patient and the dentist see and feel these contacts. The patient can feel them by rubbing the teeth together, and the clinician can feel them by placing slight pressure on the tooth in question with a finger while the patient rubs the teeth together.

Two different-colored ribbons (red and black) should be utilized to differentiate closure markings from excursive markings. Excursive movements are marked first with red, and then closure movements are marked with black. This is further described in chapter 10, which covers the details of equilibration. It will become easy for the clinician to identify working, balancing, and protrusive markings and understand the potential damaging effects from these excursive interferences.

The mechanism of micro trauma during parafunctional repetition of these contacts, both on the teeth and joint apparatus, is discussed in chapter 10. Suffice it to say at this time that the major causes of joint deterioration occur as a result of external trauma (a blow to the face or jaw) and secondarily by micro trauma. Thus, it is important to identify evidence of micro trauma, look for facial scarring that may be evidence of external trauma, and listen carefully for a history of trauma.

Range of Motion

Any of several types of devices can be used to measure the patient’s total opening and lateral movements. It is important to note if the movements are pain free and if they can be done smoothly or with difficulty. The movement measurements are compared to averages such as 40 mm in opening and 10 mm in lateral directions. Do not simply measure but also analyze the potential cause and effect of any alteration in movement or form of movement. When a patient has limited movement to one side or demonstrates a deviation to one side upon opening, the clinician should determine which of the following causes pertain to this particular patient:

• Muscle spasm or tightness that interferes with normal movement
• Disc derangement, which can block normal movement
• Arthritic or adhesive stickiness of joint and joint tissue
• Fracture of condylar structures
• Tumor
• Degenerative disease
• Neurological etiology
• Avoidance of a particular tooth interference
• Normal movement because of developmental or birth defect of the joint apparatus
• A normal effect because of irregular condylar inclinations of right and left eminences

Joint Sounds

Either with a stethoscope or Doppler, the clinician can determine whether the crepitus sounds occur on excursive movement, on direct rotation, or both. This differentiation is helpful in...

Table of contents

• Cover
• Half title page
• Title page
• Copyright page
• Preface
• Contributors
• 1 Introduction to Occlusal Disease and Rationale for Occlusal Therapy
• 2 Occlusal Parafunction and Temporomandibular Disorders: Neurobiological Considerations
• 3 The Masticatory System: Orthopedic Considerations in Function and Pathofunction
• 4 The Anatomical Basis of Occlusion
• 5 Accepted Occlusal Principles Involved in Physiologic Occlusion
• 6 Evaluating the Muscles of the Stomatognathic System and Their Role in Understanding Occlusal Disharmony and TMD
• 7 The Effect of Occlusal Forces on the Progression of Periodontal Disease
• 8 An Occlusal Basis of Treatment Planning
• 9 Occlusal Bite Splint Therapy
• 10 Occlusal Equilibration and the Diagnostic Workup
• 11 Dentist-Ceramist Communication, the Foundation of Successful Treatment
• Index