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Table of Contents
INVITED REVIEW
Year : 2012  |  Volume : 2  |  Issue : 2  |  Page : 68-77

Occlusion: The gateway to success


Department of Conservative Dentistry and Endodontics, SRM Kattankulathur Dental College and Hospital, SRM University, Potheri, Kancheepuram Dist, Tamilnadu, India

Date of Web Publication4-Sep-2012

Correspondence Address:
Bhuvaneswaran Mohan
Department of Conservative Dentistry and Endodontics, SRM Kattankulathur Dental College and Hospital, SRM University, Potheri, Kancheepuram Dist, Tamilnadu
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2229-5194.100597

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   Abstract 

Success of our clinical procedures is not a single-day entity, but instead survival on a long-term basis. The clinical longevity of our work is dependent on so many factors and when we have a closer look, all these ultimately depend on the occlusal stability. The word occlusion itself creates aversion for almost all and very conviently we try to avoid the occlusal principles thinking that we have to bother about the principles only for tempeoro-mandibular joint disorder patients. In an irony, it is true that the principles of occlusion have to be applied in our day-to-day practice to be successful. This article aims to simplify the principles of occlusion so that the readers develop interest in this most rewarding subject. Also, the clinical implication of the occlusal concepts and the treatment modalities are explained to give the readers an insight into how important this subject is for our day-to-day practice.
Clinical Relevance to Interdisciplinary Dentistry

  1. Important to understand the principles of occlusal harmony, to have a better approach to clinical examination, treatment panning. And problem solving for any restorative cases.
  2. The failure to embrace sound occlusal principles leads to a plethora of fringe-type treatment modalities and unnecessary overtreatment.
  3. If the signs of occlusal disease can be easily observed at the earliest stages, the progression of the damage can be intercepted.
  4. Not respecting the dento-facial system may result in restoration, prosthesis, or periodontal treatment failures, along with relapse of orthodontic and orthognathic surgeries.

Keywords: Comprehensive dentistry, occlusal discrepancies, occlusion, temperomandibular joint


How to cite this article:
Mohan B, Sihivahanan D. Occlusion: The gateway to success. J Interdiscip Dentistry 2012;2:68-77

How to cite this URL:
Mohan B, Sihivahanan D. Occlusion: The gateway to success. J Interdiscip Dentistry [serial online] 2012 [cited 2018 Aug 19];2:68-77. Available from: http://www.jidonline.com/text.asp?2012/2/2/68/100597


   Introduction Top


At every level of general practice, a dentist routinely faces problems of sore teeth, excessive wear, loose teeth, tempeoro-mandibular joint (TMJ) disorders and orofacial pain. A dentist who does not have a working knowledge of occlusal principles must resort to guesswork and time-wasting trial and error attempts to solve problems. Even achieving predictable function and beauty of smile design is dependent on incorporation of sound occlusal principles. When principles of occlusal harmony are understood, the entire approach to examination, treatment, and problem solving takes on a new perspective. It is a perspective that pays huge dividends of predictability and increased productivity, regardless of the type of practice. Attempting to restore an occlusion, correcting a bite problem, or even reshaping a high restoration without knowing the precisely correct maxillary-mandibular relationship, can be a time-wasting, frustrating, and unnecessary experience. [1],[2]

Even though an understanding of occlusal principles has value to every level of dental practice, there is a pervasive misconception that concepts of dental occlusion are not relevant to everyday dentistry. The failure to embrace sound occlusal principles has also led to a plethora of fringe-type treatment modalities, unnecessary overtreatment, and denials of responsibility for problems that are a direct result of occlusal mismanagement. [1],[2]

A primary tenet of comprehensive dentistry is that all of the components of the masticatory system are intimately related and dependent on one another for ideal occlusion. A true understanding of occlusion and comprehensive dentistry is important for the predictability and longevity of all the beautiful restorations that dentist create, and the overall comfort and functioning of their patients. At this point, it is needless to mention that achieving a stable occlusion requires a multidisciplinary approach and the specialist involved should have a sound knowledge of the same. Today's dentistry is shifting toward conservative and comprehensive dental care. [3],[4]

The objective of this article is to explore the role of occlusion in day-to-day practice, and to highlight the multispecialty approach required in comprehensive dentistry.


   Terminologies Top


To understand the concepts of occlusion, it is necessary that certain terminologies are well understood. A thorough knowledge of the anatomy of the TMJ and the surrounding structures is, also equally important. A few of the important terminologies and their clinical importance are listed here.

Centric relation

Definition: It is the relationship of the mandible to the maxilla when the properly aligned condyle-disk assemblies are in the most superior position against the eminentiae, irrespective of vertical dimension or tooth position.

The centric relation refers to the fully seated condylar position regardless of how the teeth fit. Centric relation is not just a convenience position that is used because it is repeatable. It is the universally accepted jaw position because it is physiologically and biomechanically correct and is the only jaw position that permits an interference-free occlusion. Because the position of the condyle-disk assemblies determines the maxillary-mandibular relationship during jaw closure, any variation in condylar position will change the closing arc of the mandible teeth against the maxillary teeth. Recording of an accurate centric relation is critical for the most cost-effective, time-effective, trouble-free restorative or prosthetic dentistry. [5],[6] The mandible is in centric relation if five criteria are fulfilled:

  1. The disk is properly aligned on both condyles.
  2. The condyle-disk assemblies are at the highest point possible against the posterior slopes of the eminentiae.
  3. The medial pole of each condyle-disk assembly is braced by bone.
  4. The inferior lateral pterygoid muscles have released contraction and are passive.
  5. The TMJs can accept firm compressive loading with no signs of tenderness or tension.


The goal of centric relation is a completely released inferior lateral pterygoid muscle on both sides. This is the essential requirement for a peaceful, coordinated musculature. It can only be achieved in the absence of deflective occlusal interferences to centric relation. In short, centric relation is bone-to-bone relationship. [7],[8]

Please remember that between bone and muscle war, muscle never loses - Harry Sicher.

Maximum intercuspation position

The tooth-to-tooth relationship in maximum contact is called as maximum intercuspation position (MIP). Earlier, this position was called as centric occlusion. The MIP might not coincide with the centric relation and that is why the terminology centric occlusion is obsolete.

To highlight again, centric relation is bone-to-bone relation and maximum intercuspation is tooth-to-tooth relation. All the problems related to occlusion begin when there is a mismatch between centric relation and maximum intercuspation (MIP). If this mismatch is minor, then the TMJ adapts itself to MIP and this posture is called as adapted centric posture. [9]

Adapted centric posture is the manageably stable relationship of the mandible to the maxilla that is achieved when deformed TMJs have adapted to a degree that they can comfortably accept firm loading when completely seated at the most superior position against the eminentiae. Beyond this stage, the muscles try to knock off all the tooth interferences to go back to their position. When succeeded, tooth wear begins; if not, TMJ problem starts. This concept is known as Hit and Slide concept. This clearly explains the reason why tooth wear pattern is just not an abrasion of enamel, but the formation of wear facets in different sizes and shapes [Figure 1]. When upper and the lower teeth contact each other, only a total area of 4mm 2 comes in contact, if marked with an articulating paper, we would get dots in the posterior and lines in the anterior. Most importantly, anterior stop is necessary for the stability of posteriors in centric relation (inverted tripod concept). When restoring teeth, all these have to be kept in mind to achieve success [Figure 2].
Figure 1: Occlusal wear facet

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Figure 2: Maximum intercuspation contacts

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Anterior guidance

Next to centric relation, the anterior guidance is the most important determination that must be made when one is restoring an occlusion. The success or failure of many occlusal treatments hinges on the correctness of the anterior guidance. The anterior guidance has similar importance in orthodontic treatment. The functional movement of mandible constitutes the most fundamental basis for ideal occlusal design. Every tooth in the mandible (the only moving jaw) has an envelope of motion (envelope of function) that outlines the outer limits of each lower tooth to be moved. During full range of anterior guidance, there should be no posterior interferences. As the lower anterior slide out, all the posterior teeth should be in complete dis-occlusion. Failure to properly establish the correct guidance is a major cause of post-treatment instability. One thing every dentist should know before attempting to restore anterior teeth is that besides being the key to esthetics, the anterior teeth are also the key factor in protecting the posterior teeth. The relationship of the anterior teeth in function is the principle determinant of posterior occlusal form. The formula to analyze the anterior guidance: dots signify centric relation contact only, on posterior teeth. Lines signify the role of the anterior teeth to disclude the posterior teeth in all excursions.

There is no way to standardize anterior guidance. There are no cephalometric norms that work for all patients, and there are no arbitrary guidelines for interincisal angulation that fit all patients. One of the most important concepts to understand about anterior guidance is that it is highly variable from patient to patient. Minute changes can make a major difference in patient comfort, and slight mistakes in incisal edge position can profoundly affect the stability of the anterior teeth over time.

In a perfected occlusion, the combination of condylar guidance and anterior guidance determines the path that the mandible follows in function. In an ideal occlusal relationship, all contact by the posterior teeth is determined by the combined border paths at both the front and back ends of the mandible. Thus, the anterior guidance plays a dominant role in establishing the functional path that the mandible can travel.

Any disturbances seen in the palatal surface of anteriors simply means that the anterior guidance is not proper. Hence, the primary aim of any treatment restorative or prosthetic work should be to get the ideal position of the anteriors and establishing perfect anterior guidance. [6],[7]

Vertical dimension of occlusion

Definition: It is the vertical position of the mandible in relation to the maxilla when the upper and lower teeth are intercuspated at the most closed position. [10],[11]

The mandible-maxilla relationship, established by the repetitive contracted length of the elevator muscles, determines the vertical dimension of occlusion (VDO). Even though the VDO occurs when the teeth are fully articulated, the teeth are not the determinants of vertical dimension. Rather their position is determined by the vertical dimension of the space available between the fixed maxilla and the muscle-positioned mandible. There is an ever-present eruptive force that causes teeth to erupt until they meet an equal, opposite force. If the opposing force is greater than the eruptive force, the teeth are intruded until the eruptive force equals the resistive force against them. If the resistive force is less than the eruptive force, the teeth will continue to erupt. [12],[13]

The dimension of the jaw-to-jaw relationship is consistent enough that even severe bruxing, clenching, and abrading parafunction do not alter the jaw-to-jaw dimension between bony landmarks in each jaw. Because of elongation of the alveolar process, even severe abrasion of teeth does not cause a loss of vertical dimension. Patients can wear their teeth down to the gum line and still not lose vertical dimension because the eruptive process matches the wear to maintain the original vertical dimension.

In very rare situations, tooth wear supersedes the bone formation and the VDO requires a change. If the VDO must be changed, it should be determined at the point of anterior teeth contact, and it should be changed as little as necessary to reduce the requirements for adaptation to the minimum. Changes in the true VDO are not permanent. The VDO will return to its original dimension measurable at the masseter muscle.

Failure to understand the physiology and biomechanics of vertical dimension will lead to inappropriate overtreatment and result in iatrogenic damage to dentition and missed diagnosis of temperomandibular joint disorders [TMD]. [14],[15]

Vertical dimension at rest (VDR)

When a muscle is neither hypotonic nor hypertonic, it is said to be at rest. Even resting muscle is in mild state of contraction. This mild contraction of antagonist muscles is necessary to maintain the posture and alignment of the skeletal parts. Despite the popularity of using rest position as a starting point for determining VDO, it is an unreliable approach because the dimension between the teeth at the rest position is not consistent for different patients. The rest position is not consistent even in the same patient. The rest position is also altered by the presence of any noxious stimuli from occlusal interferences that can cause varying degrees of muscle incoordination. The effects of masticatory muscle incoordination can range from slight hyper-contraction to severe trismus, all of which can have a profound effect on the postural position of the mandible at rest [16] [Figure 3] and [Figure 4].
Figure 3: Compensation of bone for loss of VDO

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Figure 4: Changes in bone during loss of VDO

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Please remember that between teeth and muscle war, muscle never loses - Peter E. Dawson.

Neutral zone

Definition : The potential space between the lips and cheeks on one side and the tongue on the other.

Teeth are the most movable part of the masticatory system. If outward horizontal forces from the tongue are greater than inward forces exerted by the buccinator muscle bands and the lips, the teeth will move horizontally until the opposing forces are equal. This is the neutral zone. Understanding of the neutral zone makes it readily apparent why so many orthodontic results do not remain stable. It also explains why many post-restorative problems occur and even why some periodontal procedures are unsuccessful. Relapses with orthognathic surgery can almost always be explained by neutral zone imbalance. Also, complete or partial denture failures are often related to noncompliance with neutral zone factors. Regardless of the treatment, any part of the dention out of harmony with the neutral zone will result in instability, interference with function, or some degree of discomfort [17] [Figure 5] and [Figure 6].
Figure 5: Neutral zone role of tongue and cheeks

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Figure 6: Neutral zone tongue and lip

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Plane of occlusion

The term plane of occlusion refers to an imaginary surface that theoretically touches the incisal edges of the incisors and the tips of the occluding surfaces of the posterior teeth. Together, the curve of Spee, the curve of Wilson, and the curve of the incisal edges are properly referred to as the curve of occlusion [18] [Figure 7].
Figure 7: Plane of occlusion

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Curve of spee

It is the anterioposterior curvature of the occlusal surfaces, beginning at the tip of the lower canine and following the buccal cusp tips of the bicuspids and molars, and continuing to the anterior border of the ramus. The curve of Spee aligns each tooth for maximum resistance to functional loading. The long axis of each lower tooth is aligned nearly parallel to its arc of closure around the condylar axis.

Curve of monson

If the curved line continued further back, it would ideally follow an arc through the condyle. The curvature of the arc would relate, on average, to part of a circle with a 4-inch radius. The posterior part of the occlusal plane will always be flat enough and low enough to be discluded by the normal condylar path on its steeper eminentiae. It is because of this geometric design that the 4-inch radius of the Monson curve works so effectively if the condyle is used for a survey point.

The anterior posterior curvature of the occlusal plane is designed to permit protrusive disclusion of the posterior teeth by the combination of anterior guidance and condylar guidance. Prevention of increased muscle loading on the teeth and the joints is the dominant reason for making certain that the occlusal plane is correctly evaluated as a part of every complete examination.

Curve of wilson

It is the mediolateral curve that contacts the buccal and lingual cusp tips on each side of the arch. The curve of Wilson results from inward inclination of the lower posterior teeth. There are two reasons for this inclination of posterior teeth. One has to do with resistance to loading and the second has to do with masticatory function.

The form of the occlusal plane is directly related to specific functional requirements. In addition to alignment of teeth in relationship to the arc of closure for best resistance to loading, it should permit ease of access for positioning of the food on the occlusal surfaces. The occlusal plane is a critical consideration in solving many different problems of occlusion. But if basic requirements for acceptability of an occlusion plane are understood, resolution of problem occlusions can be achieved more readily. When restoring multiple teeth or rehabilitating using prosthesis removable or fixed, it is very important that all these principles are taken care of. [19],[20]


   Types of Occlusion Top


For many years, the standard classification for occlusion has been Angle`s classification of malocclusion. The problem with Angle`s classification is that it does not consider TMJ position or condition when relating the mandibular arch to the maxillary arch. Analysis of any occlusion requires careful inspection of MIP in relation to both the position and condition of the TMJs. Probably, this is the reason why sometimes, Angle`s Class I patients develop severe TMJ problems and Angle`s Class III patients live happily without any problems.

Dawson's classification

In the analysis of any occlusion in relation to the TMJs, the condition and position of the TMJs must be determined before the occlusion can be analyzed. [21],[22],[23],[24]

Type I: Maximal intercuspation is in harmony with centric relation.

Type IA: Maximal intercuspation occurs in harmony with adapted centric posture.

Type II: Condyles must displace from a verifiable centric relation for maximum intercuspation to occur.

Type II-A: Condyles must displace from an adapted centric posture for maximum intercuspation to occur.

Type III: Centric relation cannot be verified.

Type IV: The occlusal relationship is in active stage of progressive disorder because of pathologically unstable TMJs.

Group function occlusion

Refers to distribution of lateral forces to a group of teeth.

Group function of the working side is indicated whenever the arch relationship does not allow the anterior guidance to do its job of discluding the non-functioning side. Problems with group function result from improper harmony of the contacting lines. Attempts at group function with convex inclines are invitations to hypermobility. For group function to be effective in reducing stress, the cusp inclines must be in perfect harmony with the lateral border movements of the jaw. Incline interferences on posterior teeth get progressively more stressful as they get closer to the condyle fulcrum; a slight interference on a second molar would probably be more stressful than a more noticeable interference on a canine.

Canine-protected occlusion

Refers to disclusion by the canines of all other teeth in lateral excursions. It usually serves as the cornerstone of what is called mutually protected occlusion.

When it is impractical to distribute the lateral guidance stresses over several teeth, disclusion of the posterior teeth can be accomplished by use of the canines in one form or another of canine-protected occlusion. In natural canine-protected occlusions, the pattern of function is rather vertical, and so the mandible does not use lateral movements that would subject the canines to stress in that direction either. The canines actually assume the role more as a guidance that actuates vertical function rather than as a resistor to lateral stress.

Balanced occlusion

The balanced occlusion originally referred to actual balancing contact to stabilize the dentures on the side of the downward moving, orbiting condyle. When the same concept of balanced occlusion is applied to the natural dention, it results in hypermobility, excessive wear, and periodontal breakdown. Bilaterally balanced occlusion does not work because there is no way to harmonize the balancing inclines of the teeth to all of the variations of muscle force against the unbraced orbiting condyle.


   Occlusal Disease Top


It is a puzzling observation that the most prevalent evidence or damage to teeth is so routinely ignored. The signs of occlusal disease are so easily observed even at the earliest stages when progression of the damage can usually be intercepted. If the signs and symptoms of occlusal disease are readily recognized, then they respond to treatment at a high level of predictability. [25,26]

Lytle was the first to introduce the term occlusal disease. He defined it as "the process resulting in the noticeable loss or destruction of the occluding surfaces of the teeth." He postulated that the disease is primarily, but not necessarily precipitated by bruxism or parafunction. Occlusal disease is deformation or disturbance of function of any structures within the masticatory system that are in disequilibrium with a harmonious interrelationship between the TMJs, the masticatory musculature, and the occluding surface of the teeth. To appreciate the full scope of occlusal disease, it is necessary to understand how interdependent all parts of the masticatory system are. Any disharmony between the teeth, the muscles, and the TMJs is sufficient to cause stress, deformation, or dysfunction on any or all of the other parts in the system. [27],[28]

Basic mechanisms for tooth surface deformation

According to Grippo et al., it is now apparent that deformation of tooth structure results from three basic physical and chemical mechanisms that can act alone or in combination.

  1. Stress results in compression, flexure, and tension. It can produce microfracture and abfraction as a dental manifestation.
  2. Friction includes abrasion from exogenous material and attrition, which is endogenous. The end point of both is wear of tooth surfaces.
  3. Corrosion is the result of chemical or electrochemical degradation.


These three basic mechanisms often overlap and interact to accelerate structural damage to the teeth. Thus, much of the structural deformation of teeth must be considered as multifactorial.

Examples of occlusal disease [29]



  1. Attritional wear: This type of wear on the lower anterior teeth is one of the most common untreated problems. The posterior teeth with deflective incline interferences to centric relation are so often the cause of a forward slide of the mandible during closure to maximum intercuspation. This forces the lower anterior teeth forward into a collision with the upper anterior teeth.
  2. Erosion of enamel: A combination of acid from fruit, abrasion from mulling fruit between end-to-end anterior contacts, and attrition from bruxing produces invagination of incisal enamel.
  3. Splayed teeth: Splaying of teeth is a common sign of occlusal disease that should be diagnosed and treated early by eliminating the deflective interferences that force the mandible forward. Improperly contoured restorations that are too thick on the lingual of the upper anterior teeth or overcontoured lower restorations are common cause of splaying.
  4. Destroyed dentition: This is the result of not intercepting occlusal disease early. Signs of severe wear, fractured maxillary and mandibular teeth, and elongated alveolar process are typical.
  5. Advanced occlusal disease: This disease results from a combination of attritional wear and moved teeth. This is occlusal disease left undiagnosed and untreated until the late stage of progressive damage has occurred.
  6. Anterior guidance attrition: This occurs when anterior teeth that interfere either with centric relation closure or with functional jaw movement patterns develop early signs of attritional wear of the lingual enamel on upper anterior teeth.
  7. Sore teeth: Compression of periodontal ligaments can be combined with pulpal hyperemia to cause considerable soreness or pain on biting. If empty mouth clenching causes any discomfort in a tooth, it is an indication that the sore tooth is in occlusal interference.
  8. Hypermobility: An early sign of occlusal disease is tooth hypermobility. It can result in widened periodontal space and greater susceptibility to periodontal disease.
  9. Painful musculature: A common symptom of occlusal disease results from disharmony between the occlusion and the TMJs. Deflective occlusal interferences that require the jaw joints to displace to achieve maximum intercuspation are a potent cause for painful masticatory musculature. Occlusal overload can cause excessive wear, hypermobility, fractured cusps, and hypersensitivity.



   Clinical Considerations Top


By now, it is very clear that the science behind a beautiful smile is not as simple as what we think. The dentist of today must become a physician of the total masticatory system. [30] this is not surprising because knowledge about occlusion-related issues is essential to good clinical practice in all disciplines. The loss of tooth structure is the first sign that any clinician should keep a watch to control the occlusal disease. We all know that signs precede symptoms, hence if the patient is symptomatic; it simply means that a lot of destruction has already happened. [31]

Loss of enamel resulting in attrition, both in anteriors and posteriors, is not a minor issue to be neglected. As discussed earlier, the occlusal diseases are a result of improper positioning of teeth. When unattended, this will result in periodontal destruction and ultimate loss of tooth structure. The reasons for failure of restorations, prosthesis, or periodontal treatment, and relapse of orthodontic and orthognathic surgeries are nothing, but not respecting the dentofacial system. [32]

A proper diagnosis considering all the etiological factors will avoid most of the failures in day-to-day practice. Let it be restorative treatment, prosthetic rehabilitation, or a periodontic surgery, all concepts of occlusion have to integrate to achieve success and all these branches of dentistry are interrelated and the specialists have to work in harmony. The main aim of any treatment should be to make sure that the teeth are positioned in centric relation and all our final restorations have to be in this position too. [33],[34]

Treatment planning

Step 1: To confirm if there is a discreprency between centric relation and MIP.

Step 2: Deprogramming of the patient if the discreprency is seen with anterior bite plane, Lucia jig, and Pankey jig.

Step 3: Once the muscles are deprogramming, recording the centric relation with face bow transfer is done.

Step 4: Finding out the occlusal discrepancy in semi-adjustable articulators.

Step 5: Correction of the discrepancy in the mouth.

The periodontal treatment can be initiated at this phase. After completing the periodontal treatment, once again the steps 3-5 have to be carried out to make sure that there are no occlusal discreprencies. This is because during periodontal treatment, the teeth may change their positions. It is well known that occlusal discreprencies could be the primary etiology for periodontitis, but the reason for failure of properly done periodontal rehabilitation is nothing, but not taking care of the above-mentioned factors. [35]

The restorative and the prosthetic work will start after stage 5. It is needless to say that periodontal treatment precedes all rehabilitation work.

Step 6: Temporization of patient with prototype restorations.

Prototype restorations are nothing, but the exact replica of the final restorations.

Step 7: Follow-up of the patient with temporaries. Correcting occlusal discreprencies of temporaries in both centric and eccentric position.

Step 8: If the patient is comfortable and temporaries are stable, then proceed to permanent restorations.

Step 9: Make replica of the temporaries (prototype) and communicate to the lab to make permanent restoration exactly resembling the temporaries. These final restorations, strictly speaking, should not have any changes in the mouth.

All these stages have to be followed for multiple restorative work, prosthetic reconstruction, and full mouth rehabilitation when an occlusal problem is diagnosed. If not, all restorative and prosthetic procedures have to incorporate steps 6-9 to make sure that we do not induce an occlusal problem.

[Figure 8] and [Figure 9] shows improperly done fixed prosthesis, which had resulted in severe TMD and periodontal destruction. [Figure 10] shows severe occlusal disturbance with all anterior and posterior destruction. [Figure 11] and [Figure 12] show the picture of a patient undergoing rehabilitation with prototype restoration. [Figure 13] shows severe attrition of lower posterior teeth due to severe mismatch of centric relation and MIP. It is general tendency to perform root canal therapy and restore them with ceramic crowns. Since root canal treatment and crowns will not solve patient's primary problem, root canal therapy in such cases is not at all warranted and is considered as improper diagnosis and treatment planning. [Figure 14] shows the replica of prototype with press and stain ceramic restorations. [Figure 15] shows individual table top restorations cemented in all the lower posteriors. Patient is now completely rehabilitated in accordance with centric relation. The reasons for success and failure are very vivid now. The failure, not necessary to be a catastrophic one, might range from a fracture of single composite restoration, chipping of the ceramic crowns, debonding of the fixed prosthesis to the complete instability of partial and full dentures and also unscrewing of implants. [36]
Figure 8: Improperly done fixed dental prosthesis

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Figure 9: Another case of improperly done fixed dental prosthesis

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Figure 10: Severe attrition of anterior and posterior teeth

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Figure 11: Prototype restorations done on the lower posterior teeth

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Figure 12: Occlusal view of the prototype restoration

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Figure 13: Severe attrition of lower posteriors

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Figure 14: Table top restorations

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Figure 15: Cemented table top restorations

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   Conclusion Top


The subject of occlusion has to be given much more importance in our day-to-day practice. Instead of finding out the reasons for the failure of our procedures, it is better to understand and respect the dentofacial system to avoid such failures. Within the limitation of this article, we have discussed the basics of occlusion and its role in day-to-day practice. Also, the importance of interdisciplinary approach to this problem and treatment protocol has been briefly explained. When all these concepts are followed, success is sure to come.

 
   References Top

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    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9], [Figure 10], [Figure 11], [Figure 12], [Figure 13], [Figure 14], [Figure 15]



 

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  In this article
    Abstract
   Introduction
   Terminologies
   Types of Occlusion
   Occlusal Disease
    Clinical Conside...
   Conclusion
    References
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