Металлокерамика Каппа для чемпионов

Изготовление индивидуальных капп по принципу нейро-мышечной стоматологии.

Металлокерамика Балансировка окклюзии (сделанных протезов) с помощью компьютера.

Металлокерамика Подготовка к операции имплантации

По статистике каждый третий имплант, в случае его отторжения, связан с проблемами стерилизации.

Статьи

Балансировка окклюзии (сделанных протезов) с помощью компьютера.

 

 Независимые исследования показали несостоятельность анализа окклюзионных контактов с помощью артикуляционных маркеров.

 

 

 

 

Articulating Paper Mark Misconceptions and Computerized Occlusal Analysis Technology

 

Robert B. Kerstein DMDa

 

 

a - former Assistant Clinical Professor, Department of Restorative Dentistry, Tufts University School of Dental Medicine; DMD, Certificate in Prosthodontics, Private Practice

 

 

 

 

 

Corresponding Author

Robert B. Kerstein , DMD

Practice limited to Prosthodontics and Occlusion

665 Beacon St. #204

Boston, MA 02215

617-247-1700

Fax - 617-247-1611

E mail – tmjdoc@ix.netcom.com

 

 

 

 

 

 

 

 

INTRODUCTION

 

Articulating paper foils, and ribbons have been extensively used in clinical practice during this century, primarily as Occlusal Indicators.1 Their clinical implementation requires operator subjective interpretation of the markings to decide which contacts are acceptable, and which are forceful, or time premature. What is noteworthy, is that their appearance characteristics have been described in textbooks on Occlusion2,3,5,6,7 to be descriptive of the occlusal load that created the mark. Large, dark marks, have been advocated to indicate heavy occlusal load, and smaller, lighter marks, have been advocated to indicate lesser loads.5,6,7Lastly, the presence of many similar sized marks on neighboring teeth is purported to indicate equal occlusal contact intensity, evenness, and time simultenaity.2,3 The ongoing  belief in these paper mark appearance misperceptions has been used by practitioners for well over 100 years, as a basis with which to guide clinical occlusal contact selection when correcting occlusion.

 

Most published studies about articulating paper offer no scientific evidence to suggest that articulating paper can measure occlusal loads.8,9 To date, no published study shows the size characteristics of paper marks describe the applied occlusal load. Recently, Millstein reported that, in a search through the literature, he could not find proven, scientifically - based, proper-use guidelines, for the clinician to employ when using articulating paper.1

 

Recently published research on 600 articulating paper marks made across the human occlusal force range (from 0-500N) has revealed that the size of a paper mark made during intercuspation, does not describe occlusal forces.10 Numerous mark sizes analyzed were representative of numerous differing occlusal loads10, such that a given mark of virtually any size (large, small, scratch-like, donut-shaped, light or dark in color) could hold a range of loads10.  The same study also showed that similar sized marks on neighboring teeth did not represent equal loads.10

 

Figure 1 shows how variable the marks and the loads were for all of the mandibular markings studied. Note that at 400 pixels (a single mark size) there are 7 different loads represented (outlined in blue), and at 200N (a single load) there are 16 different mark sizes represented (outlined in red). These trends are observed at each pixel size and each load tested.

 

Additionally, it was reported that only 21% of the marks correlated to the applied occlusal load, while 79% of the marks did not describe the applied load.10 The articulating paper mark sizes varied so greatly at each test load, that the authors concluded an operator would not be able to determine, from visual inspection of the size of paper markings, which marks are truly forceful and which are not.10

 

What this means to the implant clinician is, during an implant prosthesis delivery procedure, that choosing the marks to occlusally adjust based upon the “size” of the different markings, is a highly error prone method, as any size mark could contain any load (Fig. 2). Therefore

clinical use of paper mark size as an occlusal contact selection guide, will result in poor force applications to the occlusion. The occlusal design would likely contain unseen (by the operator) force aberrations that could induce long-term damage to shorten the life of any implant restoration (regardless of how uniform or “even” the articulating paper markings appeared). It is a well documented Clinical Reality that material failure and implant loss are purported to be the direct result of excessive occlusal forces being applied to the rigid implant restoration          systems.11, 12

 

Scientific evidence of this Clinical Reality can be observed in a recent study by Kaptein.13 The authors reported that after 3.25 years in service, 70% of the studied implant superstructures (52 out of 76) were damaged, despite the authors’ contention that they “balanced the occlusion and provided cuspid rise and/or group function where indicated, to lessen lateral stresses”.13 They used marking paper to assess occlusal balance and did not measure their occlusal designs, hence they assumed their occlusal schemes were balanced when most likely, they were not. Because they assessed paper markings visually, the authors actually didn’t know whether the restorations were balanced or not; they just assumed they were based upon paper mark appearance characteristics. Clearly, with such a high failure rate (70% after 3 years in service), much more precise occlusal force control is required on all the rigid implant restorations to insure restorative material survivability and prolonged Osseointegration.

 

As an alternative method to operator subjective interpretation of articulating mark appearance characteristics in choosing forceful and/or premature occlusal contacts, computerized occlusal analysis is available to the practitioner (T-Scan III Computerized Occlusal Analysis System, Tekscan, Inc., South Boston, MA).

 

COMPUTERIZED OCCLUSAL ANALYSIS SYSTEM ATTRIBUTES

Computerized occlusal analysis has evolved over the past 25 years to become a Windows® based, high-technology occlusal clinical tool, with which to understand occlusal contact functional and parafunctional forces, contact timing sequences, and occlusal surface interface pressures, which arise as teeth mill against each other during mandibular movements (Figs. 3 and 4).

 

There are numerous researched, and published clinical applications, in which computerized occlusal analysis can be employed.14-19 There are known uses in occlusal therapy17,18, TMD Treatment18, 20-24, Fixed and Removable Prosthodontics16, and Implant Prosthodontics19,25. The system can be used to diagnose occlusal problems, identify excessive occlusal contact force locations, isolate time premature contacts, and guide the operator during insertion occlusal adjustments of all forms of prosthetic and implant dentistry. Because it accurately isolates which tooth contact locations are time premature and/or too forceful, the operator can perform targeted occlusal adjustments which result in precise and predictable occlusal enpoints.17, 18  And, unlike articulating paper, within the literature, there are published proper-use guidelines that have been described for the clinician to predictably employ the technology. These guidelines have been clinically determined through years of human subject occlusal research performed from the 1980s through to the present day. 20-25  

 

A recorded occlusal function Force Movie26, when played back for data analysis, is described in colors that illustrate the various occlusal pressures. The darker, cooler colors represent low occlusal pressures whereas the brighter, warmer colors indicate higher occlusal contact pressures (Fig. 5).

 

One of the system’s most important software features is the capacity to describe the occlusal contact timing sequence in .003 second increments (which can not be observed in the articulating paper markings either) as the different occlusal contacts sequentially press on the occlusal aspect of an implant prosthesis. Figures. 6 a, b, and c are 3 successive Force Movie frames that illustrate the progression of differing evolving regions of excessive occlusal force, made during a mandibular intercuspated closure over a .16 second-long time period. The first occlusal area to become overloaded relative to its’ neighbors is the #10 and 11 region (Fig 6a); next, after .09 seconds has elapsed, the #3 and 9 regions are too forceful relative to their neighbors (Fig 3b), and lastly .07 seconds later, excessive forces can be noted in the #s 14 and 15 region (Fig. 3c). These 6 overloaded teeth were all recorded at different times in the same Force Movie, yet each was precisely isolated, and visualized, as to where in the arch, and when, a given tooth became too forceful relative to its surroundings.

 

This real-time recording capability affords the operator a dynamic occlusal Force Movie of all the occlusal contact relations, that can be played forwards or backwards continuously, or in .003 second increments, both in 2 or 3 dimensions. It simplifies for the operator, the problem of  identifying and targeting overloaded teeth for aberrant force correction.

 

PAPER MARK MISPERCEPTION CLINICAL EXAMPLE                                                          An example of a typical paper mark misperception can be seen in the case illustrated in Figure 7. This is a occlusal view of a 7 implant supported maxillary complete arch fixed/detachable prosthesis, comprised of a gold superstructure retaining pink acrylic and acrylic denture teeth. It opposes a natural lower dentition that has intercuspated the implant prosthesis with articulating paper interposed (Accufilm, Parkell, Inc. Farmingdale, NY).  The larger markings are present on the patients’ right side, and the smaller markings are on the left.

 

At first observation, the 3 “large black” markings on the patients’ right (teeth #s 3 thru 6 ) appear forceful due to their large size, whereas their left counterpart teeth (#s 11-14) show many smaller size markings in comparison . The paper mark misperception here, is that the right side contacts are thought of, and taught to be, forceful contacts, while the left side contacts are thought of, and taught to be, light force contacts. No research has ever substantiated that these author-advocated premises are true; they have , however, been widely accepted by dental medicine in the absence of scientific proof.

 

When computerized occlusal analysis measures the actual force in the 2 different appearing contact groupings however, it is revealed that the small “light” markings on the patients left side represent the high occlusal forces and the “large black” markings on the patients’ right side are actually low force contacts. And there exists a significant left side to right side force disparity equaling 78% left to 27%right (Fig. 8). If balancing the occlusion of this implant prosthesis were attempted, and had corrective occlusal adjustments been performed on the patients’ right side, with paper mark size being the guide from which to choose the “forceful” contacts, the wrong contacts would be adjusted. The excessive forces already present on the patients’ left side would be worsened, instead of  being improved. This would have led to an even greater left to right arch half force disparity, and easily resulted in the evolution of damage to the prosthesis while in service.

 

SUMMARY

Articulating paper mark size is now understood to be non-descriptive of occlusal loads such that many different sized marks can represent the same load, and equal sized marks do not represent similar loads. With only 21% reported reliability between mark size and applied occlusal load, choosing the paper marks to occlusally adjust, based upon their relative size, and operator subjective assessment of those various sizes, is tantamount to “clinical guessing”.

 

Computerized occlusal analysis completely removes the operator subjectivity from the clinical decision making process when attempting to isolate problem occlusal contacts while observing paper markings of various sizes and configurations. When an operator properly uses this technology, mark size, mark color-depth, “donut- shaped” halo contacts, as well as other color, and mark appearance characteristics, are ignored as “force indicators”, and used only as “contact locators”. Operator subjective paper mark misperceptions are replaced with accurate knowledge of the true and measured contact order, contact applied load, contact quality, and proper contact isolation where problematic. This results in overall better force application to any installed implant prostheses during occlusal function, thereby enhancing its chance for a undamaged clinical service lifespan.

Reprint Requests to:

Robert B. Kerstein, DMD

665 Beacon St. #204    

Boston, MA 02215        

 617-247-1700

tmjdoc@ix.netcom.com


REFERENCE: 

 

  1. Millstein, P. Know your indicator. J Mass Dental Soc 2008;56(4):30-31
  2. Glickman I. Clinical Periodontics. 5th ed. Philadelphia: Saunders and Co; 1979. p 951.
  3. McNeil C. Science and practice of occlusion. Carol Stream: Quintessence Publishing; 1997.  p 421.
  4. Harper KA, Setchell DA. The use of shimstock to assess occlusal contacts; a laboratory study. Int J Prosthodont. 2002;15:347-52.
  5. Okeson, J. Management of temporomandibular disorders and occlusion. 5th ed. 2003 CV

              Mosby and Co, St. Louis, MO. p. 416, 418, 605.

 

  1. Kleinberg I. Occlusion practice and assessment. Oxford: Knight Publishing; 1991. p 128.
  2.  Smukler H. Equilibration in the natural and restored dentition. Chicago: Quintessence Publishing; 1991. p. 110.
  3. Schelb E, Kaiser D, and Brukl C. Thickness and marking characteristics of occlusal

             registration strips. J Prosthet Dent 1985;54:122-6.

 

  1. Halperin G, Halperin A, Norling B. Thickness, strength, and plastic deformation of occlusal registration strips. J Prosthet Dent 1982;48:575-8.
  2. Carey JP, Craig M, Kerstein RB, Radke J. Determining a relationship between applied occlusal load and articulating paper mark area. The Open Dentistry Journal, 2007:(1);1-7
  3. Misch CE. Consideration of biomechanical stress in treatment with dental implants.

 

             Dent Today. 2006 May;25(5):80, 82, 84-5; quiz 85.

 

  1. Morgan MJ, James DF, Pilliar RM. Fractures of the fixture component of an osseointegrated implant. Int J Oral Maxillofac Implants. 1993;8(4):409-14.
  2. Kaptein MLA, DePutter C, Delange GL, Blijdorp, PA. A clinical evaluation of 76 implant supported superstructures in the composite grafted maxilla. J Oral Rehab 1999;26:619-623
  3. Kerstein, RB.  Computerized Occlusal Management of a fixed /detachable implant prosthesis.  Pract Proced Aesthet Dent 1999;11(9):1093-1102
  4. Kerstein, RB.  Montgomery, M. Mapping occlusal forces on rebuilt anterior guidance.  Cont. Esthetics; 2000;14 (4); 68-73
  5. Kerstein, RB. Current Applications of Computerized Occlusal Analysis in Dental Medicine. General Dentistry 2001;49(5);521-530.
  6. Kerstein, RB, Grundset, K., Obtaining Bilateral Simultaneous Occlusal Contacts with Computer Analyzed and Guided Occlusal Adjustments.   Quintessence Int. 2001;32:7-18
  7. Kerstein, R. Disclusion time reduction therapy with immediate complete anterior  

             guidance development: the technique. Quintessence Int. 1992;23:735–747

  1. Kerstein, R.B., Non-simultaneous Tooth Contact in Combined Implant and Natural Tooth Occlusal Schemes, Pract Proced Aesthet Dent 2002;13(9);751-756.
  2. Kerstein, RB. Wright, N., An electromyographic and computer analysis of patients suffering from chronic myofascial pain dysfunction syndrome; pre and post - treatment with immediate complete anterior guidance development. J Prosthet Dent1991;66(5):677-686.
  3. Kerstein, RB. Chapman R., and Klein, M. A comparison of ICAGD (Immediate complete Anterior Guidance Development) to "mock ICAGD" for symptom reductions in chronic myofascial pain dysfunction patients. Cranio;15(1):21-37,1997
  4. Kerstein, RB. Disclusion Time Measurement Studies: Stability of disclusion time. a 1 year follow - up study. J Prosthet Dent 1994;72(2):164 - 168
  5. Kerstein, RB. Disclusion time measurement studies; Part 2: A comparison of disclusion

            time length of 49 chronic myofascial pain dysfunction syndrome patients to 40 non -   

            patients. A population analysis. J Prosthet Dent, 1994;72(5);473- 480.

  1. Kerstein, RB. Radke J. The effect of Disclusion Time Reduction on maximal clench muscle activity level. Cranio 2006:24(3);156-165.
  2. Kerstein, RB Lowe, M Harty, M Radke, J A Force reproduction analysis of two recording sensors of a computerized occlusal analysis system.  Cranio 2006: 24(1);15-24
  3. Maness, WL.  Force Movie: A Time and Force View of Occlusal Contacts, Compend Contin Educ. Dent:10(7); 404 -408.

 

 

 

 

LEGENDS

 

Figure 1
 

 – Distribution of mark sizes at various loads for the mandibular teeth. Reprinted from Carey, et.al. The Open Dentistry Journal, 2007:(1);1-7. Note at 400 pixels (a given mark size) there are 7 different loads represented (outlined in blue), and at 200N (a given load) there are 16 different mark sizes represented (outlined in red),

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fig 2 – Articulating paper markings of a maxillary implant supported bridge. Current research has shown that any size mark could contain any occlusal load despite size and appearance

 
 

 

 

 

 

 

 

 

 

 

 

 

Figure 3 – T-Scan III System Recording Handle and Sensor  

 

 
 

 

 

 

 

 

 

 

 

 

 

 

Figure 4 – USB recording handle connected to a computer workstation (laptop)

 
 

 

 

 

 

 

 

 

 

 

 

 

Figure 5 – T-Scan III Desktop

 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 6a- Early contacts at 7.9% total force in a mandibular closure Force Movie. Teeth #s 10 and 11 are early and forceful to their neighbors

 

 

 

 

 

 

 

 

 

 

Figure 6b – Middle of mandibular closure Force Movie at 39.7% total force.09 seconds later. Teeth #s 3 and 9 are forceful relative to their neighbors

 
 

 

 

 

 

 

 

 

 

 

 

 
 

Figure 6c – Later in same mandibular closure Force Movie at 73.6% of total force .07 seconds later. Teeth #s 14 and 15 are forceful relative to all teeth

 

 

 

 

 

 

 

 

 

 

Figure 7 – An occlusal view of a 7 implant supported maxillary complete arch fixed/detachable prosthesis, comprised of a gold superstructure retaining pink acrylic and acrylic denture teeth

 
 

 
 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 8 – T-Scan III force analysis of the implant supported maxillary complete arch fixed/detachable prosthesis seen in Figure 7,