CLINICAL PRACTICE: PRACTICAL SCIENCE |
Centric relation
A historical and contemporary orthodontic perspective
Donald J. Rinchuse, DMD, MS, MDS, PhD and
Sanjivan Kandasamy, BDSc, BScDent, DocClinDen, MOrthRCS
 |
ABSTRACT
|
|---|
Background. Centric relation (CR) has been a controversial subject in dentistry for more than a century. For at least the past four decades, issues involving CR have been of interest to orthodontists. The definition of CR has changed over the past half-century from a retruded, posterior and, for the most part, superior condyle position to an anterior-superior condyle position.
Type of Studies Reviewed. The authors addressed the historical and contemporary orthodontic perspective of CR. The source material for this review came mainly from literature and searches the lead author accumulated over the last 30 years. As there is no evidence-based (EB) model level 3 (systemic) review on the topic of CR, the best evidence on this subject was gleaned only from a thorough examination and evaluation at EB model level 2 (experience plus best available sample studies). There was, however, enough high-quality EB model level 2 information on the topic of CR for the authors to draw conclusions on the basis of a scientific appraisal of relevant research.
Results. Although the reliability of CR records has been substantiated, the records’ validity has little to no evidentiary support. In addition, population-based sample studies and consensus statements from national conferences support the view that the positions of the temporomandibular joint (TMJ) condyles in relation to the glenoid fossa or CR position are not diagnostic of temporomandiblar disorders. There appears to be little to no benefit of using gnathologic records and articulator-mounted dental casts to discern discrepancies in maximum intercuspation of the teeth coincident with TMJ condyles in an anterior-superior CR position in orthodontic patients.
Clinical Implications. The benefit of using gnathologic CR records and articulators in orthodontics has not been substantiated by scientific evidence.
Key Words: Centric relation; condyle position; orthodontics
The search for the optimal and preferred types of static and functional occlusions has occupied the minds of dentists for more than a century. The possible role of occlusion in the etiology of temporomandibular disorders (TMD) also has been the subject of debate. Much of the occlusion/TMD debate involves issues surrounding centric relation (CR), including definition, recording and measurement, use of articulators and deprogramming splints, and possible relationship to either stomatognathic health or disease. The purpose of this article is to discuss some of the controversies concerning CR, particularly as they relate to orthodontics.
Because there is no evidence-based (EB) model level 3 (systemic) review on the topic of CR, the best evidence on this subject can be gleaned only from a thorough examination and evaluation at EB model level 2 (experience plus best available sample studies). However, there is enough high-quality EB model level 2 information on the topic of CR to draw several noteworthy conclusions. Therefore, we drew conclusions on the basis of a scientific appraisal of relevant research based on the EB model level 2 paradigm. One author (D.J.R.) accumulated the majority of the source material for this article from literature and searches he conducted over 30 years.
|
DEFINITIONS OF CENTRIC RELATION AND CENTRIC OCCLUSION
|
|---|
Dentistry has not arrived at a consensus definition and concept of CR. In 2004, Christensen1 said that he and most practitioners "accept the concept that CR is the most comfortable posterior location of the mandible when it is bilaterally manipulated gently backward and upward into a retrusive position." However, CR has not been recognized as a posterior, retruded condyle position for almost 20 years.2 In 2000, Jasinevicius and colleagues3 found that faculty and students at seven dental schools could not agree on a unified definition of CR.
The definition of CR has evolved over the past half-century from being a posterior and superior position of the condyle in relation to the glenoid fossa to an anterior-superior position.2,4–7 Before 1987, CR was considered a retruded (posterior-superior) condylar position. The latest edition of the Glossary of Prosthodontic Terms (GPT)7 defines CR as "a maxillomandibular relationship in which the condyles articulate with the thinnest avascular portion of their respective disks with the complex in the anterior-superior position against the slopes of the articular eminences." This edition of GPT also includes six historical definitions of CR.7
Centric relation is a position of the condyles independent of tooth contact, whereas centric occlusion is an interocclusal dental position of the maxillary teeth relative to the mandibular teeth.
CR is a position of the condyles independent of tooth contact, whereas centric occlusion (CO) is an interocclusal dental position of the maxillary teeth relative to the mandibular teeth.2 Maximum intercuspation (MI) has been defined as "the complete intercuspation of opposing teeth independent of condylar position."6 Although CO and MI have been used synonymously in the past, the most recent editions of GPT6,7 have made a distinction between the two terms; this has not been well-received within the profession, most likely owing to resistance to change.
The common use of the terms "centric relation-centric occlusion" and "centric relation-maximum intercuspation" discrepancies, or slides, in some publications is inaccurate, because CR is not comparable with CO or MI. CR is a condyle position, while CO and MI are interocclusal dental positions. A previously used term that all editions of the GPT considered obsolete and referenced along with CO is "centric relation occlusion" (CRO). Decades ago, CRO was used by gnathologists to describe the interocclusal position of the teeth when the condyles were located in retruded CR.4,5 Past usage of the term "centric relation occlusion–centric occlusion" discrepancies, or slides, was semantically appropriate. To avoid some of the confusion about the term "CR-CO," one publication appropriately used the term "CO condyles" compared with CR.8 Recently, CO-CR (or CR-CO) and MI-CR (or CR-MI) in which MI is synonymous with CO, have been use interchangeably. Other "centric" terms found in the literature are intercuspal position (ICP), which is used synonymously with CO, and retruded cuspal position (RCP), which is a modern reference to the previously used term CRO. Hence, some publications have used the term "RCP-ICP" slides. In our literature review, common and historical usage of terms will take precedent over any attempt for total accuracy.
|
CENTRIC RELATION AND ORTHODONTICS
|
|---|
The call for orthodontists to consider the functional aspects of the dentition dates back to at least the 1930s; several of the prominent pioneers were Brodie,9,10 Perry,11,12 Moyer,13 Thompson14–18 and Ricketts.19,20 In the 1970s, Roth,21–25 a gnathologic orthodontist, suggested that orthodontists should embrace the principles of gnathology that had long been held by eminent prosthodontists and restorative dentists. He reasoned that orthodontic treatment is analogous to doing full-mouth occlusal rehabilitation, with the difference being that orthodontics did not "cut" or modify the natural tooth structure. Purveyors of this view were critical of nongnathologic orthodontists for what they saw as their lack of concern about establishing an "optimal" functional occlusion in addition to attaining the long-held traditional goals of static occlusion. A focus of this gnathologic orthodontic view was to establish a retruded, posterior-superior "seated" CR position when the interdigitating occlusion was in CO (that is, CR-CO). The thinking then was that if a posterior-superior seated CR position was not an established goal of orthodontic treatment, patients would be prone to develop TMJ symptoms.21–25 Furthermore, the attainment of a retruded, posterior-superior CR position would mitigate the development of TMD.
Many aspects of this gnathologic orthodontic view have been abandoned, particularly those related to the attainment of a retruded, posterior-superior CR position. An impetus for this shift in thinking was the introduction of more sophisticated TMJ imaging that demonstrates TMJ internal derangements and that has led to the change in the definition of CR from a posterior-superior to an anterior-superior position. The argument for anterior-superior positioned condyles was the belief that distally displaced condyles can cause anterior and medial displacement of the TMJ disks. With this thinking in mind and relating it to orthodontics, Wyatt26 argued that Class II, division 2 malocclusions; missing posterior teeth with bite collapse; any occlusal contacts that may deflect the condyles posteriorly; and orthodontic procedures such as the placement of Class II elastics, headgear, chin cups and certain retainers can cause TMD. However, this notion and others from this era were found to be untrue,27–47 particularly the idea that orthodontic treatment causes TMD.33,37,39,42–46 Changes in the definition and concept of CR have been determined arbitrarily for the most part and were not based on science and EB decision making. Concerning the ideas and notions of the early orthodontic gnathologists, Johnston47 wrote, "It could be argued that the progressive modifications in the definition of CR have done more to eliminate centric slides than 20 years of grudging acquiescence of the precepts of gnathology."
Although contemporary orthodontic gnathologists believe in attaining an anterior-superior condyle position at the same time the teeth are in CR (CR-CO), there is little scientific evidence to support this view.27 In fact, the evidence supports a contrary notion. The location and position of the condyles in the glenoid fossa, irrespective of where they may be, has not been demonstrated to be consequential to the presence or absence of TMD symptoms.48–51 Keim52 said, "The neuromuscular school tells us that there is a range of acceptable positions (centric) ... If we clinicians continue to place emphasis on establishing ‘harmony’ between CO and some mythical concept of CR, we are doing ourselves a disservice."
|
CONDYLE POSITION AND CENTRIC SLIDES
|
|---|
The findings in the 1960s that centric slides caused TMD were based on incorrect information from descriptive studies that lacked control/comparison groups. When control/comparison groups that included subjects without TMD were added to the studies’ designs, the exact same centric slides also were observed in these subjects (comparison group subjects who did not have TMD). Hence, many of these studies had high diagnostic sensitivity but poor diagnostic specificity, which led to false-positive TMD diagnoses.53,54 Furthermore, intraoral telemetry studies of the 1960s, in which miniature radio implants were placed in subjects’ fixed prostheses and radio frequencies were monitored from outside the mouth, found that even though entire dentitions were reconstructed into retruded CR, subjects continued to use and function in CO.55–58 In a summary article, McNamara and colleagues59 found TMJ arthropathies associated with centric slides greater than 4 millimeters; however, they contended that the slides were the result of the TMD rather than the cause.
In summary, the preponderance of evidence available suggests that there is no one ideal position of the condyles in the glenoid fossa, but there is a range of "normal" positions.27,47,53,59 That is, the three-dimensional position and location of the condyles in the glenoid fossa are not predictive of TMD.60,61 Based primarily on dialectical considerations rather than on evidence, anterior to mid-condyle positions appear to be favored over posterior, retruded positions.27–32,34–38
|
RETRUDED CENTRIC RELATION: THE PAST DATA
|
|---|
In the 1960s and 1970s, CRO was considered to be the interocclusal position of the teeth when the mandibular condyles were in retruded CR.4 The location of retruded CR was calculated from an interocclusal centric record (that is, CO and CRO) made from the teeth and not the condyles. Early studies found that CO usually was 0.1 to 1.8 mm anterior to CRO, depending on the population studied and the age of the subjects.62–64 Chin-point guided records found CO (or CRO) condyles to be located on average 0.28 to 0.56 mm anterior and 0.26 to 0.85 mm inferior to retruded CR.65,66
Although there was some variation in the findings from intraoral telemetric studies, the preponderance of evidence suggested that, though a few CRO contacts were found to occur during swallowing, most swallowing and all chewing contacts occurred in CO.55–58 Furthermore, lateral functional occlusal contacts originate from CO and not from CRO.55–58 As we previously mentioned, telemetry research has indicated that even when patients’ entire dentitions were reconstructed in retruded CR, they still persisted in using CO.58 In addition, retruded CR was not believed to be a natural and physiological condyle position, but rather an extreme border position.67–71 Interestingly, Jankelson and colleagues72 supported the view that neither CRO nor CO was physiological and, therefore, advocated what they termed the "myocentric" position or muscle (masticatory) -generated centric position. They believed that the myocentric position usually was located between CRO and CO. On the other hand, Schuyler 73 and Mann and Pankey74 advocated a "long centric" position, in which occlusal prematurities, or interferences, were eliminated to and from CRO and CO.
Many prosthodontists use retruded centric relation only as a guide so that dentures can be fabricated a millimeter or so anterior to this position.
|
CENTRIC RECORDS: RETRUDED CENTRIC RELATION
|
|---|
The early literature on recording CR is related to retruded CR, not to anterior-superior CR. Furthermore, most CR recordings are dentist-manipulated, and there are differences in findings from manipulated and unmanipulated CR recordings.61 Dentist-manipulated CR records (also known as passive patient CR records) are considered to be more reliable and less valid than patient-manipulated records.75–84 One investigation demonstrated the average range of centric slide for repeated recordings of retruded CR to be 0.30 mm mediolaterally and 0.27 mm anteroposteriorly.85 It appears that recording of retruded CR in contemporary dentistry makes sense only in complete denture construction when no interocclusal reference is possible. Even then, many prosthodontists use retruded CR only as a guide so that dentures can be fabricated a millimeter or so anterior to this position.
|
ANTERIOR-SUPERIOR CENTRIC RELATION
|
|---|
Logically, one would think that changing the definition of CR from a posterior-superior to an anterior-superior position would have eliminated or reduced the magnitude of centric slides.47 To a degree, this has proven to be true. Orthodontic gnathologists recently have found only minor MI-CR discrepancies for the vertical dimension, but not the horizontal and transverse dimensions.86 The magnitude of the vertical MI-CR discrepancy is approximately 1 mm. When the errors in method, recording and instrumentation are calculated against this 1 mm figure, the importance of these findings can be insignificant.81 Nonetheless, orthodontic gnathologists argue that consideration and measurements of MI-CR slides or discrepancies are still valid.21–25,86–92
Using a Roth "power centric bite registration" and articulator-mounted models, Utt and colleagues90 found that CO condyles were located on average 0.53 mm posterior and 0.72 mm inferior to anterior-superior CR. There was, however, a significant amount of individual variation, with 39 percent of the CO condyles positioned anteroinferiorly from anterior-superior CR.90 Based on Utt and colleagues90 and Crawford,88 orthodontic gnathologists claim that anterior-superior CR slides average 0.6 to 0.7 mm horizontally, 0.7 to 0.8 mm vertically and 0.27 to 0.3 mm transversely.89 Recent investigations comparing gnathologic with non gnathologic finished orthodontic cases generally have found articulator-recorded MI-CR differences of 1 mm or greater in the vertical plane in non gnathologically treated cases (1.41 mm for the nongnathologically treated versus 0.41 mm for the gnathologically treated; difference of 1 mm).87
|
A CRITICAL APPRAISAL OF THE CONTEMPORARY ORTHODONTIC GNATHOLOGIC APPROACH
|
|---|
Today’s gnathologically oriented orthodontists advocate the use of articulators with dental casts mounted in anterior-superior CR, with the major goal of orthodontic treatment being to establish coincidence of MI-CR.86,93 Accordingly, they believe that the tolerance for MI-CR discrepancies is 1.5 mm in the horizontal (H) and vertical (V) planes and 0.5 mm in the transverse (T) plane (average: Utt and colleagues,90 2.0 mm H and V, 0.5 mm T; Crawford,88 1.0 mm H and V, 0.5 mm T).87–91 They further contend that articulator-mounted casts, instead of hand-held dental casts, are the only way to discern the MI-CR discrepancies. For instance, using articulator-mounted dental casts, Klar and colleagues89 found a statistically, but perhaps not clinically, significant change in the pre– versus post–MI-CR recordings (differences of no more than 0.39 mm in any of the three spatial planes) among 200 consecutively gnathologically treated orthodontic patients. Lastly, gnathologically oriented orthodontists advocate the use of the terminal hinge axis position, the need for pretreatment CR-MI–converted lateral cephalograms and the placement of gnathologic positioners immediately after orthodontic appliances are removed.92
On the other hand, nongnathologic orthodontists tend to use hand-held models and noninstrument-oriented CR techniques. They favor more general treatment goals that include the attainment of the best occlusal relationship within the framework of optimal dentofacial esthetics, function and stability. Furthermore, they believe that there is a tolerance for MI-CR slides up to 2 to 4 mm in the horizontal plane with little or no attention given to the relevance of the vertical and transverse dimensions.27,47,59
Orthodontic gnathologists argue that the assessment of three-dimensional condylar position is not possible with two-dimensional TMJ radiography, but it is through the use of the Roth power centric bite registration with articulator-mounted dental casts.21–25,65,86–93 This view may ignore the possible benefit of TMJ magnetic resonance imaging (MRI) to assess condyle position.8 Nevertheless, orthodontic gnathologists believe that it is possible to locate a particular position of the condyles precisely in the glenoid fossa via CR recordings.
A two-piece bite registration technique by Roth called the "power centric bite registration" is believed to seat the condyles in the optimal, anterior-superior CR position—or as Utt and colleagues90 wrote, "condyles centered transversely and seated against the articular disk at the posterior slope of the articular eminences without dental interferences." Roth,21–25 Kulbersh and colleagues,86,87 Crawford,88 Klar and colleagues,89 Utt and colleagues,90 Schmitt and colleagues,91 Lavine and colleagues92 and Cordray,93 however, failed to provide evidence (preferably MRI evidence) that subjects’ condyles are positioned in a seated anterior-superior CR. Hence, it can be argued that there is no verification that the Roth power centric bite registration "captures" (positions and records) condyles in anterior-superior CR.27 And contrary to Roth’s thinking, there is evidence that CR recordings do not place condyles in the positions stated by their advocates. Alexander and colleagues8 provided TMJ MRI documentation that condyles are not located in the assumed positions as advocated and provided by several gnathologic centric bite registrations. Centric bite registrations attempting to locate retruded (posterior-superior) CR and contemporary anterior-superior CR do not correspond to the condyle positions of people with asymptomatic TMD.
CR gnathologic recording techniques such as Roth power centric bite registration and articulator mounting instrumentation have been demonstrated to be somewhat reliable (repeatability and consistency of the records or techniques).91,92 We, however, question the validity of these recordings, as well as point out that there is error in them. For instance, one study found standard deviations for gnathologic MI-CR records to be as high as 0.16 mm in the H and V planes and 0.13 mm in the T plane; the error was calculated as 0.01 to 0.05 mm.92 Because there are only small differences between gnathologic and nongnathologic MI-CR recorded discrepancies, even a small amount of error calculated against any of the gnathologic study findings would further reduce the clinical significance of the findings. Therefore, we ask if small centric MI-CR discrepancies found by gnathologists are clinically significant and whether they have any relationship to patients’ stomatognathic health. Furthermore, the gnathologic data may be based on questionable research.27
The validity of CR recordings and the use of articulators in orthodontics is based on the concept of the terminal hinge axis. However, Posselt’s94 1952 concept of a terminal hinge axis has been challenged by Lindauer and colleagues’95 theory of simultaneous and instantaneous rotation and translation of the mandibular condyles. According to this theory, the mandibular condyles both initially rotate and translate around an axis, which action continues as the jaw opens.
In 1995, Lindauer and colleagues95 studied the condylar movements and centers of rotation during jaw opening in eight subjects without TMD using a sonic digitizing system. They found that all of the subjects demonstrated both rotation and translation during the initial phase of jaw opening, and none had a center of rotation at the condylar head. Their findings support the theory of a constantly moving, instantaneous center of jaw rotation that is different for different people. Because articulators do not incorporate any initial translatory movement of the condyles during jaw opening, Lindauer and colleagues95 concluded that the use of articulators to simulate "jaw movements to identify occlusal interferences cannot be expected to replicate the patient’s mandibular movement precisely." They further argue that "the uncertainty of predicting mandibular rotation for a given patient should be considered when planning surgical treatment and fabrication of orthodontic appliances."95
|
DEPROGRAMMING
|
|---|
The need to "deprogram" patients from their pre-existing occlusions with occlusal splints before taking CR recordings is controversial. Gnathologists in general hypothesize that the mastication muscles can affect adversely the mandible’s position in the presence of occlusal interferences owing to memorized patterns and proprioceptive sensory information.24 They also hypoth esize that the condyles are prohibited from being seated appropriately unless a deprogramming splint precedes CR bite registrations.93 Deprogramming splints are thought to provide a more physiological muscular engram than what exists by allowing the mastication muscles to mitigate temporarily the proprioceptive errors caused by occlusal prematurities.21–25,89,93 Some orthodontic gnathologists21–25,93,96–98 believe that patients, even patients without TMD, need to be deprogrammed before their CR records are obtained—sometimes for as long as three months. Some orthodontic gnathologists also argue that orthodontic patient diagnosis is not complete unless deprogramming splints and articulator-mounted dental casts are used.21,98–100
The need to ‘deprogram’ patients from their pre-existing occlusions with occlusal splints before taking centric relation recordings is controversial.
Nonetheless, use of deprogramming splints lacks a true physiological basis and the evidence to support it is equivocal. While some investigations have demonstrated a possible benefit of deprogramming,101,102 others have not.87,103 In addition, articles have discussed the techniques, benefits or both of deprogramming.104–107 Both sample studies used deprogrammers for relatively short periods.102,103 Karl and Foley102 placed a "Lucia-type anterior deprogramming jig" (that is, anterior tooth contact without posterior tooth contact) in 40 subjects with TMD for six hours and found differences of only fractions of a millimeter in centric registration when a deprogrammer was used; the difference may not be clinically significant. Conversely, Kulbersh and colleagues87 did not find a difference in MI-CR measurements between orthodontic patients who wore full-coverage deprogrammers for three weeks for 24 hours a day and those who did not.
There are many unanswered questions concerning deprogramming splints.
- – Is there a difference in findings between anterior and full-coverage deprogrammers?
- – Would a longer period of wearing a deprogramming splint yield larger differences?
- – Are the fractions-of-a-millimeter differences in centric registrations produced by deprogramming splints clinically significant?
- – How much of the small centric differences between deprogrammed CR records and traditional records are due to recording and measurement errors?
- – Are the deprogrammed condyles being seated in the predicted glenoid fossa position?
- – What is the reliability and validity of deprogramming splints for recording CR?
- – Is the deprogrammed centric registration a stable position?
- – Is the deprogrammed position physiological?
- – Is the deprogrammed position more physiologi cal than the original centric position?
- – Does the deprogrammed centric position have anything to do with stomatognathic health?
|
CONCLUSIONS
|
|---|
The definition of CR has changed over the past half-century from a posterior and retruded condylar position to an anterior-superior position. The evidence suggests that condyle position and CR position are not diagnostic of TMD. Although dentist-manipulated CR recordings are more reliable than unmanipulated CR recordings, they are less valid and physiological. Recent evidence suggests that the concept of a "terminal hinge axis" may not be valid, as there is an "instantaneous center of rotation" in which the condyles actually rotate and translate simultaneously. There appears to be little benefit of using gnathologic records and articulator-mounted dental casts to discern MI-CR discrepancies in orthodontic patients. The use of deprogramming splints is equivocal, with the best approximation leaning toward the view that their use is not EB.
|
FOOTNOTES
|
|---|
Dr. Rinchuse is a clinical professor, Orthodontics and Dentofacial Orthopedics, University of Pittsburgh, School of Dental Medicine. Address reprint requests to Dr. Rinchuse at 510 Pellis Road, Greensburg, Pa. 15601, e-mail "bracebrothers{at}aol.com".
Dr. Kandasamy is a research fellow in orthodontics, Oral Health Centre, University of Western Australia, Perth, and is in orthodontic practice, Perth, Australia.
A small portion of this article is reprinted from Rinchuse,27 with the permission of the American Association of Orthodontists.
|
REFERENCES
|
|---|
- Christensen GJ. Is occlusion becoming more confusing? A plea for simplicity. JADA 2004;135:767–70.
- Glossary of prosthodontic terms. J Prosthet Dent 1987;58:713–62.[Medline]
- Jasinevicius TR, Yellowitz JA, Vaughan GG, et al. Centric relation definitions taught in 7 dental schools: results of faculty and student surveys. J Prosthodont 2000;9(2):87–94.[Medline]
- Academy of Denture Prosthetics. Glossary of prosthodontic terms (appendix). J Prosthet Dent 1956;692:5–34.
- The Nomenclature Committee Academy of Denture Prosthetics; Hickey JC, Boucher CO, Hughes GA, Glossary of prosthodontic terms. 3rd ed. J Prosthet Dent 1968;20:444–80.
- The Academy of Prosthodontics Glossary of prosthodontic terms. 6th ed. J Prosthet Dent 1994;71(1):41–112.[Medline]
- The Academy of Prosthodontics. Glossary of prosthodontic terms. 7th ed. J Prosthet Dent 1999;81(1):39–110.[Medline]
- Alexander SR, Moore RN, DuBois LM. Mandibular condyle position: comparison of articulator mountings and magnetic resonance imaging. Am J Orthod Dentofacial Orthop 1993;104:230–9.[Medline]
- Brodie AG. Differential diagnosis of joint conditions in orthodontia. Angle Orthod 1934;4:160–70.
- Brodie AG. The temporomandibular joint. Ill Dent J 1939;8:2–12.
- Perry HT Jr. Principles of occlusion applied to modern orthodontics. Dent Clin North Am 1969;13:581–90.[Medline]
- Perry HT. Temporomandibular joint and occlusion. Angle Orthod 1976;46:284–93.[Medline]
- Moyer RE. An electromyographic analysis of certain muscles in temporomandibular movement. Am J Orthod 1950;36:481–515.[Medline]
- Thompson JR. The rest position of the mandible and its significance to dental science. JADA 1946;33:151–80.
- Thompson JR. Concepts regarding function of the stomatognathic system. JADA 1954;48:626–37.
- Thompson JR. Anatomical and physiological considerations for positions of the mandible. Dent J Aust 1951;23(4):161–6.
- Thompson JR. Abnormal function of the temporomandibular joints and related musculature: orthodontic implications, Part I. Angle Orthod 1986;56(2):143–63.[Medline]
- Thompson JR. Abnormal function of the temporomandibular joints and related musculature, orthodontic implications, Part II. Angle Orthod 1986;56(3):181–95.[Medline]
- Ricketts RM. Laminography in the diagnosis of temporomandibular joint disorders. JADA 1953;46:620–48.
- Ricketts RM. Clinical implications of the temporomandibular joint. JADA 1966;52:416–39.
- Roth RH. Temporomandibular pain-dysfunction and occlusal relationships. Angle Orthod 1973;43(2):136–53.[Medline]
- Roth RH. The maintenance system and occlusal dynamics. Dent Clin North Am 1976;20:761–88.[Medline]
- Roth RH. Functional occlusal for the orthodontist. J Clin Orthod 1981;15(1):32–51.[Medline]
- Roth RH. Treatment mechanics for the straight-wire appliance. In: Graber TM, Swain BF, eds. Orthodontics, current principles and techniques. St. Louis: Mosby; 1985;665–716.
- Roth RH. Functional occlusion for the orthodontist, Part III. J Clin Orthod 1981;15(3):174–9, 182–98.[Medline]
- Wyatt WE. Preventing adverse effects on the temporomandibular joint through orthodontic treatment. Am J Orthod Dentofacial Orthop 1987;91:493–9.[Medline]
- Rinchuse DJ. Counterpoint: a three-dimensional comparison of condylar change between centric relation and centric occlusion using the mandibular position indicator. Am J Orthod Dentofacial Orthop 1995;107:319–28.[Medline]
- Gianelly AA. Orthodontics, condylar position, and TMJ status. Am J Orthod Dentofacial Orthop 1989;95:521–3.[Medline]
- Gianelly AA, Hughes HM, Wohlgemuth P, Gildea G. Condylar position and extraction treatment. Am J Orthod Dentofacial Orthop 1988;93:201–5.[Medline]
- Gianelly AA. Condylar position and Class II deep-bite, no-overjet malocclusions. Am J Orthod Dentofacial Orthop 1989;96:428–32.[Medline]
- Gianelly AA, Cozzani M, Boffa J. Condylar position and maxillary first premolar extraction. Am J Orthod Dentofacial Orthop 1991;99:473–6.[Medline]
- Gianelly AA, Anderson CK, Boffa J. Longitudinal evaluation of condylar position in extraction and nonextraction treatment. Am J Orthod Dentofacial Orthop 1991;100;416–20.[Medline]
- O’Reilly MT, Rinchuse DJ, Close J. Class II elastics and extractions and temporomandibular disorders: a longitudinal prospective study. Am J Orthod Dentofacial Orthop 1993;103:459–63.[Medline]
- Kircos LT, Ortendahl DA, Arakawa M. Magnetic resonance imaging of the TMJ disc in asymptomatic volunteers. J Oral Maxillofac Surg 1987;45:852–4.[Medline]
- Bean LR, Thomas CA. Significance of condylar positions in patients with temporomandibular disdorders. JADA 1987;114(1):76–7.
- Le Resche L, Truelove EL, Dworkin SF. Temporomandibular disorders: a survey of dentists’ knowledge and beliefs. JADA 1993;124(5): 90–106.
- Rinchuse DJ. Counterpoint: preventing adverse effects on the temporomandibular joint through orthodontic treatment. Am J Orthod Dentofacial Orthop 1987;91:500–6.[Medline]
- Rinchuse DJ, Rinchuse DJ. The impact of the American Dental Association’s guidelines for the examination, diagnosis, and management of temporomandibular disorders on orthodontic practice. Am J Orthod Dentofac Orthop 1983;83:518–22.
- Rinchuse DJ, Sassouni V. An evaluation of functional occlusal interferences in orthodontically treated and untreated subjects. Angle Orthod 1983;53(2):122–30.[Medline]
- Ahlgren J, Posselt U. Need of functional analysis and selective grinding in orthodontics: a clinical and electromyographic study. Acta Odontol Scand 1963;21:187–226.[Medline]
- Ingervall B. Tooth contacts on the functional and non-functional side in children and young adults. Arch Oral Biol 1972;17:191–200.[Medline]
- Kim MR, Graber TM, Viana MA. Orthodontics and temporomandibular disorders: a meta-analysis. Am J Orthod Dentofacial Orthop 2002;121:438–46.[Medline]
- Reynders RM. Orthodontics and temporomandibular disorders: a review of the literature (1966–1988). Am J Orthod Dentofacial Orthop 1990;97:463–71.[Medline]
- Luther F. Orthodontics and the temporomandibular joint: where are we now? Part 1: orthodontics and temporomandibular disorders. Angle Orthod 1998;68:295–304.[Medline]
- Sadowsky C, BeGole EA. Long-term status of temporomandibular joint function and functional occlusion after orthodontic treatment. Am J Orthod 1980;78:201–12.[Medline]
- Sadowsky C, Polson AM. Temporomandibular disorders and functional occlusion after orthodontic treatment: results of two long-term studies. Am J Orthod 1984;86:386–90.[Medline]
- Johnston LE Jr. Fear and loathing in orthodontics: notes on the death of theory. In: Carlson DS, Ferrara AM, eds. Craniofacial growth theory and orthodontic treatment. Ann Arbor, Mich.: Center for Human Growth and Development, University of Michigan; 1990:75–91.
- McNeill C, Mohl ND, Rugh JD, Tanaka TT. Temporomandibular disorders: diagnosis, management, education, and research. JADA 1990;120:253–7.
- Dixon DC. Diagnostic imaging of the temporomandibular joint. Dent Clin North Am 1991;35(1):53–74.[Medline]
- Mohl ND, Dixon DC. Current status of diagnostic procedures for temporomandibular disorders. JADA 1994;125(1):56–64.
- Katzberg RW, Westesson PL, Tallents RH, Drake CM. Orthodontics and temporomandibular joint internal derangement. Am J Orthod Dentofacial Orthop 1996;109:515–20.[Medline]
- Keim RG. Centric Shangri-La. J Clin Orthod 2003;37:349–50.[Medline]
- Mohl ND. Temporomandibular disorders: the role of occlusion, TMJ imaging, and electronic devices—a diagnostic update. J Am Coll Dent 1991;58(3):4–10.
- Mohl ND, Lund JP, Widmer CG, McCall WD Jr. Devices for the diagnosis and treatment of temporomandibular disorders, Part II: electromyography and sonography. J Prosthet Dent 1990;63(3):332–6. (Published erratum appears in J Prosthet Dent 1990;63[5]:13.)[Medline]
- Pameijer JH, Brion M, Glickman I, Roeber FW. Intraoral occlusal telemetry, V: effect of occlusal adjustment upon tooth contacts during chewing and swallowing. J Prosthet Dent 1970;24:492–7.[Medline]
- Adams SH 2nd, Zander HA. Functional tooth contacts in lateral and in centric occlusion. JADA 1964;69:465–73.
- Glickman I, Martigoni M, Haddad A, Roeber FW. Further observations on human occlusion monitored by intraoral telemetry (abstract 612). International Association for Dental Research 1970:201.
- Pameijer JH, Glickman I, Roeber FW. Intraoral occlusal telemetry, 3: tooth contacts in chewing, swallowing and bruxism. J Periodontol 1969;40:253–8.[Medline]
- McNamara JA Jr, Seligman DA, Okeson JP. Occlusion, orthodontic treatment, and temporomandibular disorders: a review. J Orofac Pain 1995;9(1):73–90.[Medline]
- Report of the president’s conference on the examination, diagnosis, and management of temporomandibular disorders. JADA 1983;106(1):75–7.
- Management of temporomandibular disorders. National Institutes of Health Technology Assessment Conference Statement. JADA 1996;127:1595–606.
- Sicher H, DuBrul EL. Oral anatomy. Mosby: St. Louis, 1970: 155–60.
- Ingervall B. Recording of retruded positions of mandible in children: a comparison between registrations in general anaesthesia and with children awake. Odontol Revy 1968;19(4):413–21.[Medline]
- Ingervall B. Recording of retruded positions of mandible in children. Odontol Revy 1968;19(1):65–82.[Medline]
- Hoffman PJ, Silverman SI, Garfinkel L. Comparison of condylar position in centric relation and in centric occlusion in dentulous subjects. J Prosthet Dent 1973;30:582–8.[Medline]
- Ramfjord SP, Ash MM. Occlusion. 3rd ed. Philadelphia: Saunders; 1983:71–6.
- Sicher H. Positions and movements of the mandible. JADA 1954;48:620–5.
- Silverman MM. Comparative accuracy of the gnathological and neuromuscular concepts. JADA 1978;96:559–65.
- Sheppard IM, Sheppard SM. Range of condylar movement during mandibular opening. J Prosthet Dent 1965;15:263–71.[Medline]
- Sheppard IM, Sheppard SM. Maximal incisal opening: a diagnostic index? J Dent Med 1965;20:13–5.[Medline]
- Sheppard IM, Jacobson HG, Zaino C, Poppel MH. Dynamics of occlusion. JADA 1959;58(3):77–84.
- Jankelson B, Hoffman GM, Hendron JA Jr. The physiology of the stomatognathic system. JADA 1952;46:375–86.
- Schuyler CL. Fundamental principles in the correction of occlusal disharmony, natural and artificial. JADA 1935;22:1193–1202.
- Mann AW, Pankey LC. Concepts of occlusion: the P.M. philosophy of occlusal rehabilitation. Dent Clin North Am 1963;7(3):621–36.
- Helkimo M, Ingervall B, Carlsson GE. Comparison of different methods in active and passive recordings of the retruded position of the mandible. Scand J Dent Res 1973;81:265–71.[Medline]
- Helkimo M, Ingervall B, Carlsson GE. Variation of retruded and muscular position of mandible under different recording conditions. Acta Odontol Scand 1971;29:423–37.[Medline]
- Ingervall B, Helkimo M, Carlsslon GE. Recording of the retruded position of the mandible with application of varying external pressure to the lower jaw in man. Arch Oral Biol 1971;16:1165–70.[Medline]
- Kantor ME, Silverman SI, Garfinkel L. Centric-relation recording techniques: a comparative investigation. J Prosthet Dent 1972;28: 593–600.[Medline]
- Smith HF Jr. A comparison of empirical centric relation records with location of terminal hinge axis and apex of the gothic arch tracing. J Prosthet Dent 1975;33:511–20.[Medline]
- Shafagh I, Yoder JL, Thayer KE. Diurnal variance of centric relation position. J Prosthet Dent 1975;34:574–82.[Medline]
- Strohaver RA. A comparison of articulator mountings made with centric relation and myocentric position records. J Prosthet Dent 1972;28:379–90.[Medline]
- Long JH Jr. Location of the terminal hinge axis by intraoral means. J Prosthet Dent 1970;23(1):11–24.[Medline]
- Lundeen HC. Centric relation records: the effect of muscular action. J Prosthet Dent 1974;31:244–53.[Medline]
- Celenza FV. The centric position: replacement and character. J Prosthet Dent 1973;30:591–8.[Medline]
- Simon RL, Nicholls JI. Variability of passively recorded centric relation. J Prosthet Dent 1980;44(1):21–6.[Medline]
- Kulbersh R, Kaczynski R, Freeland T. Orthodontics and gnathology: introduction. Semin Orthod 2003;9(2):93–5.
- Kulbersh R, Dhuta M, Navarro M, Kaczynski R. Condylar distraction effects of standard edgewise therapy versus gnathologically based edgewise therapy. Semin Orthod 2003;9(2):117–27.
- Crawford SD. Condylar axis position, as determined by the occlusion and measured by the CPI instrument, and signs and symptoms of temporomandibular dysfunction. Angle Orthod 1999;69(2):103–15.[Medline]
- Klar NA, Kulbersh R, Freeland T, Kaczynski R. Maximum inter-cuspation-centric relation disharmony in 200 consecutively finished cases in a gnathologically oriented practice. Semin Orthod 2003;9(2): 109–16.
- Utt TW, Meyers CE Jr, Wierzba TF, Hondrum SO. A three-dimensional comparison of condylar position changes between centric relation and centric occlusion using the mandibular position indicator. Am J Orthod Dentofacial Orthop 1995;107:298–308.[Medline]
- Schmitt ME, Kulbersh R, Freeland T, Bever K, Pink FE. Reproducibility of the Roth power centric in determining centric relation. Semin Orthod 2003;9(2):102–8.
- Lavine D, Kulbersh R, Bonner P, Pink FE. Reproducibility of the condylar position indicator. Semin Orthod 2003;9(2):96–101.
- Cordray FE. Centric relation treatment and articulator mountings in orthodontics. Angle Orthod 1996;66(2):153–8.[Medline]
- Posselt U. Studies in the mobility of the human mandible. Acta Odontol Scand 1952;10(supplement 10):1–160.[Medline]
- Lindauer SJ, Sabol G, Isaacson RJ, Davidovitch M. Condylar movement and mandibular rotation during jaw opening. Am J Orthod Dentofacial Orthop 1995;107(6):573–7.[Medline]
- Roth R, Rinchuse DJ. CR-CO coincidence and the use of articulators. Debate held at: Northeastern Society of Orthodontists meeting; Dec. 7, 1997; New York City.
- Creekmore DC, Cetlin NM, Ricketts RM, Root TL, Roth RH. JCO roundtable: diagnosis and treatment planning. J Clin Orthod 1992;26:585–606.
- Shildkraut M, Wood DP, Hunter WS. The CR-CO discrepancy and its effect on cephalometric measurements. Angle Orthod 1994;64: 333–42.[Medline]
- Williamson EH, Caves SA, Edenfield RJ, Morse PK. Cephalometric analysis: Comparisons between maximum intercuspation and centric relation. Am J Orthod 1978;74:672–7.[Medline]
- Wood DP, Elliot RW. Reproducibility of the centric relation bite registration technique. Angle Orthod 1994;64:211–20.[Medline]
- Broekhuijsen ML, van Willigen JD. Factors influencing jaw position sense in man. Arch Oral Biol 1983;28:387–91.[Medline]
- Karl PJ, Foley TF. The use of a deprogramming appliance to obtain centric relation records. Angle Orthod 1999;69(2):117–25.[Medline]
- Kinderknecht KE, Wong GK, Billy EJ, Li SH. The effect of a deprogrammer on the position of the terminal transverse horizontal axis of the mandible. J Prosthet Dent 1992;68(1):123–31.[Medline]
- Hartzell DH, Maskeroni AJ, Certosimo FC. Techniques in recording centric relation. Oper Dent 2000;25:234–6.[Medline]
- Hunter BD 2nd, Toth RW. Centric relation registration using an anterior deprogrammer in dentate patients. J Prosthodont 1999;8(1):59–61.[Medline]
- Carroll WJ, Woelfel JB, Huffman RW. Simple application of anterior jig or leaf gauge in routine clinical practice. J Prosthet Dent 1988;59:611–7.[Medline]
- Lucia VO. Principles of articulation. Dent Clin North Am 1979;23(2):199–211.[Medline]
TOP
ABSTRACT
DEFINITIONS OF CENTRIC RELATION...
