Winter Week 3 Dentd 1532 2024 Occlusion PDF

STATIC OCCLUSION II OCCLUSAL CONTACTS Jeffrey Wascher DDS  PART 1 OCCLUSION (WINTER) 1. STATIC OCCLUSION I. REST POSITION AND INTERMAXILLARY RELATIONS 2. STATIC OCCLUSION II. OCCLUSAL CONTACTS 3. DYNAMIC OCCLUSION I. MASTICATORY CYCLE. ENVELOPE OF FUNCTION 4. DYNAMIC OCCLUS...

STATIC OCCLUSION II OCCLUSAL CONTACTS Jeffrey Wascher DDS  PART 1 OCCLUSION (WINTER) 1. STATIC OCCLUSION I. REST POSITION AND INTERMAXILLARY RELATIONS 2. STATIC OCCLUSION II. OCCLUSAL CONTACTS 3. DYNAMIC OCCLUSION I. MASTICATORY CYCLE. ENVELOPE OF FUNCTION 4. DYNAMIC OCCLUSION II. MANDIBULAR MOVEMENTS. 5. OCCLUSION REVIEW PART 2 (SPRING) 1. OCCLUSIAL CONTACTS AND MANDIBULAR MOVEMENTS. CLINICAL CONSIDERATIONS 2. OCCLUSION REVIEW FOR FINAL  OCCLUSION STATIC OCCLUSION II OCCLUSAL CONTACTS  LEARNING OBJECTIVES 1. DEFINE OCCLUSALEQUILIBRIUM 2. DEFINE ALL THE PLANES AND CURVES OF DENTAL OCCLUSION 3. LOCATE CENTRIC CONTACTS ON MAXILLARY ANTERIORTEETH 4. DIFFERENTIATE FUNCTIONAL FROM NON-FUNCTIONALCUSPS 5. IDENTIFY ADEQUATE OCCLUSAL CONTACTS OF ANTERIOR AND POSTERIOR TEETH 6. EXPLAIN THE IMPORTANCE OF ARTICULATING PAPER AND THE METHOD TO USE IT INTRAORALLY 4  This is occlusion! This also is occlusion!  OCCLUSAL EQUILIBRIUM Simultaneous contacts on all teeth at occlusion, without shift or displacement of the mandible Equilibrated occlusion happens when contacts on the teeth create harmony on the bite without any discomfort, muscular pain or temporomandibular alteration OCCLUSAL EQUILIBRIUM REQUIRES ADEQUATE DISTRIBUTION OF OCCLUSAL CONTACTS  PLANES OF OCCLUSION  PLANES AND CURVES OF OCCLUSION ANTERIOR OCCLUSALPLANE CURVE OF SPEE CURVE OF WILSON POSTERIOR OCCLUSAL PLANE ANTERIOR OCCLUSAL PLANE It is a line traced along the Maxillary incisal edges It is determined by the cusp tips of the : *Maxillary Central Incisors *Maxillary Lateral Incisors *Maxillary Canines Dawson, P. ANTERIOR OCCLUSAL PLANE Can be corrected With orthodontia With fixed prosthodontics  ANTERIOR OCCLUSAL PLANE (also called INCISAL PLANE) INVERTED CAN BE CORRECTED THROUGH: -Orthodontia (more conservative) -Cosmetic dentistry using ceramics or composite resins (more invasive)  ANTERIOR OCCLUSAL PLANE Also called the INCISAL PLANE  CLINICAL CASE Correction Of Canted Smile Porcelain Veneers #6-11 to lengthen maxillary right anterior and esthetics Lithium Disilicate crowns #5 & #12 for esthetics Botox injection to relax muscle pull on mandibular lip area #27 Photo public domain  CURVE OF SPEE The curve of Spee was described by F. Graf Von Spee in 1890. It is defined as line that begins with the cusp tip of the mandibular canine and follows the buccal cusp tips of the premolar and molar teeth, continuing through the anterior border of the Sagittal Plane mandibular ramus and ending at the anterior aspect of the mandibular condyle (Glossary of Prosthodontic terms 1994) INFLUENCE OF THE CURVE OF SPEE Lateral guidance (mandibular movement) Posterior interferences (grinding) Parafunctional habits TMJ / TMD *Excessive curve of Spee alters the muscle balance, ultimately leading to the improper functional occlusion Kumar, K. P., 2012 IMPORTANCE OF THE CURVE OF SPEE It has been proposed that an imbalance between the anterior and the posterior components of occlusal force can cause the lower incisors to over-erupt, the premolars to infra-erupt and the lower molars to be mesially inclined. Kumar, K. P., 2012 EXCESSIVE CURVE OF SPEE Excessive curve of Spee alters the muscle imbalance, ultimately leading to the improper functional occlusion. :22  CURVE OF WILSON It is defined as a transverse curve that passes along the buccal and lingual cusps of the premolars and molars. It is observed from a coronal (frontal) plane. Coronal (Frontal) Plane Dawson, P. :22 CURVE OF WILSON TH IS C U R V E C A N V A RY DEPENDING ON THE BUCCO-LINGUAL INCLINATION OF PREMOLARS AND MOLARS Convex in the maxillary arch Concave in the mandibular arch Common Problem With Orthodontic Tray Aligners: When trying to move maxillary molars buccally to expand the arch, the molars tip which changes the Curve of Wilson SAGITTAL FRONTAL PLANE PLANE  POSTERIOR PLANE OF OCCLUSION It is a plane that passes midway between the cusp tips of the mandibular molars and through the incisal edges of the mandibular incisors It is not symmetrical but described as an “ average wave” plane It is different for everyone It can be altered through growth, orthodontics and dentistry  POSTERIOR PLANE OF OCCLUSION It is a plane that passes midway between the cusp tips of the mandibular molars and through the incisal edges of the mandibular incisors It is not symmetrical but described as an “ average wave” plane It is different for everyone It can be altered through growth, orthodontics and dentistry It is a combination of the curve of Spee and the Curve of Wilson WHAT HAPPENS WHEN WE BITE? POSTERIOR OCCLUSION ANTERIOR OCCLUSION  REMEMBER: CLASS III LEVER Our masticatory system FULCRUM TMJ LOAD Food FORCE Muscles As we move more posterior, the occlusal tables get larger Bigger The closer to the fulcrum (TMJ), the more force on Bigger occlusal surfaces necessitating an occlusal Big table with increased support and strength Big Small Small This also allows for more efficient mastication At Rest Position There Is No Occlusal Contact  MAXILLARY TEETH Posterior Teeth Protect The Anterior Teeth In Static Occlusion MANDIBULAR TEETH DURING CLOSING MOVEMENT SIMULTANEOUS CONTACT OF BOTH MAXILLARY AND MANDIBULAR TEETH SUPPORT THE OCCLUSION LOAD Missing posterior teeth can lead to un-balanced occlusal forces. Destructive shearing forces can develop on anterior teeth  MAXILLARY TEETH Missing posterior teeth can lead to occlusal unbalance MANDIBULAR TEETH Occlusal overload on maxillary and mandibular anterior teeth Besides chewing efficiency, why do we need to convince our patients to keep their posterior teeth vs. choosing extraction? POSTERIOR TEETH PROTECT ANTERIOR TEETH FROM SHEAR FORCES DURING OCCLUSION ANTERIOR TEETH  MAXILLARY CENTRAL INCISOR MAXILLARY LATERAL INCISOR TOOTH #8 The centric contact is located on Mesial Marginal Ridge (on lingual surface) TOOTH #7  MAXILLARY CANINE Occlusal contacts on Maxillary Canines are located on the Mesial Marginal Ridge :35  ANTERIOR TEETH Ideal Maxillary Occlusal Contacts POSTERIOR TEETH  Not All Cusps Have The Same Function! This makes posterior occlusion much more complicated! :35  POSTERIOR TEETH Ideal Mandibular Posterior Static Occlusal Contacts  FUNCTIONAL CUSP Cusps that occlude with the opposite teeth in Maximum Intercuspation NOTE: The cusp tip does not occlude with the deepest portion of the fossa! NON-FUNCTIONAL CUSP Cusps that do not occlude with the opposing teeth in Maximum Intercuspation  NON-FUNCTIONAL CUSP FUNCTIONAL CUSP Tooth #3 BUCCAL LINGUAL Tooth #30 FUNCTIONAL CUSP NON-FUNTIONAL CUSP FUNCTIONAL CUSP= STAMP CUSP = WORKING CUSP  FUNCTIONAL CUSP (STAMP, WORKING) MAXILLARY LINGUAL CUSP MANDIBULAR BUCCAL CUSP NON-FUNCTIONAL CUSP (SHEAR, NON-WORKING) MAXILLARY BUCCAL CUSP MANDIBULAR LINGUAL CUSP  BUCCAL LINGUAL OCCLUSAL FORCES SHOULD BE DIRECTED TOWARD THE LONG AXIS OF ALL POSTERIOR TEETH But how do we accomplish this when we do not have/ want contact on cusp tips?  SHEAR or STAMP or NON-FUNCTIONAL FUNCTIONAL CUSP CUSP NOTE: The cusp tip does not occlude with the deepest portion of the fossa! A B C BUCCAL LINGUAL STAMP or SHEAR or FUNCTIONAL NON-FUNCTIONAL CUSP CUSP PARALLELOGRAM OF FORCES The vectors of occlusion direct the forces along the long axis of the tooth  STAMP or SHEAR or FUNCTIONAL NON-FUNCTIONAL CUSP CUSP BUCCAL LINGUAL STAMP or SHEAR or FUNCTIONAL NON-FUNCTIONAL CUSP CUSP THIS OCCLUSAL SCHEME ALLOWS FOR IDEAL CONTACT 2 occlusal contacts on functional cusp 1 contact on non-functional cusp 1 light contact on marginal ridge  WHAT HAPPENS IF OCCLUSAL CONTACTS NOT DIRECTED ALONG THE LONG AXIS OF THE TOOTH ? INADEQUATE PLACEMENT OF CONTACTS LEADS TO OVERLOADS AND FRACTURE OF THE WEAKEST CUSPS  FUNCTIONAL CUSPS HAVE MORE VOLUME THAN NON-FUNCTIONAL CUSPS NON-FUNCTIONAL FUNCTIONAL (SHEAR CUSP) (STAMP CUSP) IS 40% OF TOTAL IS 60% OF TOTAL OF B-L WIDTH OF B-L WIDTH  Tooth #30 FUNCTIONAL NON-FUNCTIONAL HISTOLLOGICALLY, FUNCTIONAL CUSPS HAVE HIGHER VOLUME What’s this? THAN NON- FUNCTIONAL CUSPS Buccal Lingual Khera, Carpetner et al. ANATOMY OF CUSPS OF POSTERIOR TEETH AND THEIR FRACTURE POTENTIAL. JPD 1990; 64: 139-47  Tooth #13 STAMP or SHEAR or FUNCTIONAL NON-FUNCTIONAL CUSP CUSP Lingual Buccal 60% 40% Khera, Carpetner et al. ANATOMY OF CUSPS OF POSTERIOR TEETH AND THEIR FRACTURE POTENTIAL. JPD 1990; 64: 139-47  OCCLUSAL TABLE: FUNCTION and EFFICIENCY Occlusal table functional area increases distally Orange represents functional areas Maxillary and Mandibular first molars have the largest occlusal tables INTRAORAL OCCLUSAL ANALYSIS What are we looking for when we check static intraoral occlusion?  ✓ We Check The Static Contacts In Maximum Intercuspation Heavier ✓ We identify the heavier centric contacts Lighter Heavier ✓ We see the location of the centric contacts ✓ We check the number of centric Lighter contacts per tooth (Remember static contacts are point contacts, not line contacts) It gives us an overall OCCLUSAL SCHEME of the patient Helps identify normal and abnormal contacts :47  Articulating Paper Ink- coated paper strips used to locate and mark occlusal contacts Articulating Paper Holder Journal of Prosthetic Terms, 9th edition  WHAT THICKNESS OF ARTICULATING PAPER SHOULD WE USE? Use thin double sided (Red/ Blue) 20-micron paper Avoid thicker 100-micron paper. Difficult to determine heavy occlusal contacts Red may be difficult to see on highly polished gold May need to use multiple sheets on one patient if doing a large amount of adjustments Articulating paper Articulating film 100 µm thick 20µm thick More accurate results Does not alter proprioceptive information Halperin GC, Halperin AR, Norling BK. Thickness, strength, and plastic deformation of occlusal registration strips. J Prosthet Dent. 1982 Nov;48(5):575-8. Sharma, A., Rahul, G. R., Poduval, S. T., Shetty, K., Gupta, B., & Rajora, V. (2013). History of materials used for recording static anddynamic occlusal contact marks: a literature review. Journal of clinical and experimental dentistry, 5(1), e48–e53. https://doi.org/10.4317/jced.50680 Brizuela-Velasco, Aritza (07/2015). "Influence of Articulating Paper Thickness on Occlusal Contacts Registration: A Preliminary Report.". The International journal of prosthodontics (0893-2174), 28 (4), 360.  2. Have the patient open the mouth, insert the 1. Place articulating film in the holder articulating film and have the patient bite (NOT CLENCHING). Ask for tap-tap biting. Observe the maximum intercuspation contacts Check bite contacts on the: Patient’s Right Posterior Patient’s Left Posterior Patient’s Anterior 45 :47  OBJECTIVES OF AN OCCLUSAL CHECK-UP 1. Identify normal contacts in maximum intercuspation 2. Identify abnormal harmful contacts in maximum intercuspation  OBJECTIVES OF AN OCCLUSAL CHECK-UP 1. Identify normal contacts in maximum intercuspation Intensity of the contact: They should be “pin-point” size contacts, not large oval areas of contact Contact position on posterior teeth Contact position on anterior teeth  OBJECTIVES OF AN OCCLUSAL CHECK-UP 2. Identify abnormal or detrimental contacts Premature contacts Excessive number of contacts Heavy contacts  Large area of Avoid contact on contact on the the buccal surfaces cusp tip AVOID PIN-POINT CONTACT STRIVE FOR  Minimum 3 contacts on the occlusal table in Cusp To Flat Surface contacts: 1 functional cusp 1 non-functional cusp 1 marginal ridge -make sure it is not excessive and on solid tooth/ restoration, not on a restoration margin TYPES OF OCCLUSAL CONTACT SCHEMES 1) Cusp To Flat Surface 2) Tripodization CUSP TO FLAT SURFACE THIS OCCLUSAL SCHEME ALLOWS FOR IDEAL CONTACT 2 occlusal contacts on functional cusp 1 contact on non-functional cusp 1 light contact on marginal ridge  CUSP TO FLAT SURFACE NOTE: The Axial loading cusp does not accomplished by occlude with cusp to flat surface the deepest contacts portion of the fossa! THIS OCCLUSAL SCHEME ALLOWS FOR IDEAL CONTACT 2 occlusal contacts on functional cusp 1 contact on non-functional cusp 1 light contact on marginal ridge Axial Loading by Cusp To Flat Surface Contacts Axial Loading is The cusp tip is NOT achieved by cusp in contact with the to flat surface deepest portion of developing forces the fossa! This perpendicular to would lead to the long axis of shearing forces and the tooth an unstable occlusion! Okeson, J. 2020  CUSP TO FLAT SURFACE Even if during the fabrication of a restoration a contact is lost , the remaining forces will provide the necessary stability while directing the forces through the long axis of the tooth. Can develop adequate contacts against flat occlusal amalgams and bruxism surfaces when immediate lateral translation movement can widen fossa to eliminate potential eccentric contacts (more on this in the next lecture) More practical and widely applicable compared to Tripodization  TRIPODIZATION Tripodization Axial Loading by Reciprocal Incline Contacts allows for the resultant Requires that occlusal force each cusp to de directed contacting an through the opposing fossa long axis of the be developed tooth thereby such that it allowing the produces three PDL to accept contact points and reduce surrounding the damaging actual cusp tip occlusal forces. Okeson, J 2020  TRIPODIZATION Difficult to develop and maintain all of the reciprocating contacts through the fabrication and delivery phase of a fixed restoration- if a contact is lost than this will provide an unstable bite Difficult to fabricate if the opposing surface is flattened through bruxism or previously placed flat occlusal contour Need immediate anterior disclusion in eccentric movements (more on this in the next lecture). Best suited when restoring both Maxillary and Mandibular at the same time. THINGS TO REMEMBER Anterior Occlusal Plane Posterior Occlusal Plane Curve of Spee Curve of Wilson Functional versus non-functional cusps Parallelogram of forces Anterior teeth contacts Posterior contacts After 2 Hours Of Talking Occlusion- I Think All Of Our Brains Are Full! Until Next Time… Thank You  QUESTIONS ? [email protected] Contributions to this lecture from Carolina Garcia DDS much appreciated  Sources Dawson, Peter E. Functional Occlusion From TMJ to Smile Design 2007 Glossary of Prosthetic Terms 2009 9th edition Khera, Carprtner, et al. Anatomy of cusps of posterior teeth and their fracture potential. Journal of Prosthetic Dentistry 1990; 64 139-147. Halperin, G.C. Thickness, strength, and plastic deformation of occlusal registration strips. Journal of Prosthetic Dentistry 1982 Nov; 48 575-578. Brizoula-Velcsco, A. Influence of articulating paper thickness on occlusal contacts registration. The International Journal of Prosthodontics 2015; 360 Okeson, J. Management of Temporomandibular Disorders and Occlusion. 2020 8th edition. Garcia DDS, Carolina. Midwestern University This presentation may contain copyrighted material (“Material”), the use of which may not have been specifically authorized by the copyright owner. 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