Temporomandibular joint/ fellowships in orthodontics


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Temporomandibular joint/ fellowships in orthodontics

  1. 1. TEMPOROMANDIBULAR JOINT www.indiandentalacademy.com INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com
  3. 3. INTRODUCTION www.indiandentalacademy.com
  4. 4. Temporomandibular Joint • The area where the craniomandibular articulation occurs is called the temporomandibular joint • Bilateral diarthrodial joint • Atypical synovial joint • Ginglymoarthrodial joint • Compound joint www.indiandentalacademy.com
  5. 5. CLASSIFICATION • Fibrous • Cartilaginous • Synovial www.indiandentalacademy.com
  6. 6. Fibrous joints • Sutures • Syndesmoses • Gomphoses www.indiandentalacademy.com
  7. 7. Cartilaginous joints • Synchondroses • Symphysis www.indiandentalacademy.com
  8. 8. Synovial joints www.indiandentalacademy.com
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  14. 14. DEVELOPMENT • Articular Disc:Earliest appearance in 6 week old embryo • At 7 weeks: the future condyle is still only a condensation of mesenchyme resting on osseous lamella, which forms the mandibular ramus. • 12 week – condylar growth cartilage makes its 1st appearance and begins to develop a hemi-spherical articular surface . • By 13th week – condyle and articular disc having moved up into contact with temporal bone.www.indiandentalacademy.com
  15. 15. DEVELOPMENT • Only when such articular contact has been made do the joint cavities develop. • Inferior space appearing first. • Disc begins to get compressed. • When central portion of disc is compressed this part becomes avascular. www.indiandentalacademy.com
  16. 16. DEVELOPMENT By 26th week: • All components of TMJ present except articular eminence. • Meckel’s cartilage still extends through GF, but by thirty- first week is transformed into sphenomandibular ligament. By 39th week: • Ossification of bones in this region has proceeded to the point where; ligament gains its apparent attachment to spine of sphenoid. www.indiandentalacademy.com
  17. 17. DEVELOPMENT www.indiandentalacademy.com
  18. 18. HISTOLOGY OF ARTICULAR SURFACES • The Articular surface of the condyle and mandibular fossa are composed of four distinct layers • Articular zone • Proliferative zone • Fibrocartilaginous zone • Calcified cartilaginous zone www.indiandentalacademy.com
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  20. 20. HISTOLOGY www.indiandentalacademy.com
  21. 21. HISTOLOGY www.indiandentalacademy.com
  22. 22. Condylar cartilage • Similar to epiphyseal cartilage • Endochondral ossification • Absence of ordered column of cells • Unidirectional and multidirectional growth pattern www.indiandentalacademy.com
  23. 23. Bony components Condylar head Glenoid fossa Articular eminence Muscles Muscles involved in mastication. Facial muscles. Muscles of the neck Soft tissue Articular disc Joint capsule Ligaments Muscles attached to joint FUNCTIONAL ANATOMY www.indiandentalacademy.com
  24. 24. BONY COMPONENTS www.indiandentalacademy.com
  25. 25. www.indiandentalacademy.com
  26. 26. www.indiandentalacademy.com
  27. 27. SQUAMOUS PART OF THE TEMPORAL BONE • Mandibular or articular or glenoid fossa • Degree of the convexity- dictates the pathway of the condyle • Posterior roof of the mandibular fossa is thin www.indiandentalacademy.com
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  29. 29. BOUNDARIES www.indiandentalacademy.com
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  33. 33. Condyloid process • It is the portion of the mandible that articulates with the cranium around which movement occurs • Anterior view it has a medial and lateral projection s which are called as poles • ML length - 15 to 20 mm • AP length - 8 to 10mm. www.indiandentalacademy.com
  34. 34. • Posterior articulating surface is greater than anterior surface. • The articulating surface of condyle is quite convex anteroposteriorly and only slightly convex mediolaterally. • Pterygoid fovea on the antero-medial aspect of the mandibular neck where inferior head and most fibres of the superior head and lateral pterygoid muscle insert on the mandible. www.indiandentalacademy.com
  35. 35. www.indiandentalacademy.com
  36. 36. Condyloid process Anterior Posterior www.indiandentalacademy.com
  37. 37. www.indiandentalacademy.com
  38. 38. ARTICULAR DISC • Dense fibrous connective tissue devoid of blood vessels and nerves • Sagittal plane divided into three regions according to the thickness • Central area is thinnest and it is called intermediate zone www.indiandentalacademy.com
  39. 39. • Anterior is thick • Posterior is thick • Articular surface of the condyle located on the intermediate zone of the disc bordered by the thicker anterior and posterior regions • Shape of the disc governed by the morphology of the condyle and the mandibular fossa www.indiandentalacademy.com
  40. 40. Articular disc www.indiandentalacademy.com
  41. 41. www.indiandentalacademy.com
  42. 42. • The articular disc is attached posteriorly to the region of loose connective tissue that is highly vascularized and innervated which is called as retrodiscal tissue or posterior attachments or bilaminar region. • The articular disc is attached to the capsular ligament not only anteriorly and posteriorly and also medially and laterally this divides the joint into two distinct cavities. www.indiandentalacademy.com
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  47. 47. Capsule • Seals joint space • Passive stability • Anatomically recognizable ligaments • Extension into joint • Active stability from proprioception www.indiandentalacademy.com
  48. 48. Joint capsule (attachment) www.indiandentalacademy.com
  49. 49. www.indiandentalacademy.com
  50. 50. www.indiandentalacademy.com
  51. 51. www.indiandentalacademy.com
  52. 52. Ligaments • As with any joint system, ligaments play an important role in protecting the structures • The ligaments of joints are made up of collagenous connective tissues which do not stretch. • They do not enter actively into joint function but instead act as a passive restraining devices to limit and restrict border movements www.indiandentalacademy.com
  53. 53. 3 functional ligaments that support the TMJ • Collateral ligaments • Capsular ligaments • Temporomandibular ligament 3 accessory ligaments • Sphenomandibular ligament • Stylomandibular ligament • Retinacular ligament www.indiandentalacademy.com
  54. 54. Collateral ligaments • Discal ligaments • They attach the medial and lateral borders of the articular disc to the poles of the condyle • Medial discal ligament –attaches the medial edge of the disc to the medial pole of the condyle • Lateral discal ligament-attaches the lateral edge of the disc to the lateral pole of the condyle www.indiandentalacademy.com
  55. 55. • These ligaments are responsible for dividing joint mediolaterally into superior and inferior joint cavities • The discal ligaments are true ligaments, composed of collagenous c.t fibers –they do not stretch • Restrict the movement of disc away from the condyle that means they allow the disc to move passively with condyle as it glides anteriorly and posteriorly www.indiandentalacademy.com
  56. 56. • The attachment of discal ligaments permit the disc to be rotated anteriorly and posteriorly on the articular surface of the condyle thus the these ligaments are responsible for the hinging movements of the TMJ. • The discal ligaments have a vascular supply and are innervated • This innervation provides information regarding joint position and movement • Strain on these ligaments produce pain www.indiandentalacademy.com
  57. 57. Anterior view www.indiandentalacademy.com
  58. 58. Capsular ligament • Entire TMJ is surrounded and encompassed by the capsular ligament • The fibers of capsular ligament are attached superiorly to the temporal bone along the borders of articular surfaces of the mandibular fossa and articular eminence • Inferiorly attach to the neck of the condyle www.indiandentalacademy.com
  59. 59. • Capsular ligament acts to resist any medial ,lateral or inferior forces that tend to separate or dislocate articular surfaces • A significant function of the capsular ligament is to encompass the joint ,thus retaining the synovial fluid. • The capsular ligament is well innervated and provides proprioceptive feedback regarding position and movement of the joint. www.indiandentalacademy.com
  60. 60. www.indiandentalacademy.com
  61. 61. Mesial aspect www.indiandentalacademy.com
  62. 62. Temporomandibular ligament • The lateral aspect of the capsular ligament is reinforced by strong,tight fibers that make up lateral ligament or temporomandibular ligament. • The temporomandibular ligament is composed of 2parts 1. Outer oblique portion 2. Inner horizontal portion www.indiandentalacademy.com
  63. 63. • Outer oblique portion-extends from the outer surface of the articular tubercle and zygomatic process posteroinferiorly to the outer surface of condylar neck. • Inner horizontal portion-extends from outer surface of the articular tubercle and zygomatic process posteriorly and horizontally to the lateral pole of the condyle and the posterior part of the articular disc. www.indiandentalacademy.com
  64. 64. • The inner horizontal portion of TM ligament limits posterior movement of the condyle and disc. • When force applied to the mandible displaces the condyle posteriorly,this portion of ligament becomes tight and prevents the condyle from moving into the posterior region of mandibular fossa by which it protects the retrodiscal tissues from trauma. • The inner horizontal portion also protects the the lateral pterygoid muscle from over lenghtening or over extension www.indiandentalacademy.com
  65. 65. www.indiandentalacademy.com
  66. 66. TM Ligaments www.indiandentalacademy.com
  67. 67. www.indiandentalacademy.com
  68. 68. RETINACULAR LIGAMENTS • Recently it has been described in association with TM joint. • Arises from the articular eminence, descends along the ramus of the mandible. • Insertion: fascia overlying the masseter muscle at the angle of the mandible. • As the ligament is connected to the posterolateral aspect of the retrodiscal tissues and contains an accompanying vein. • Action: It maintains blood circulation during the masticatory movements. www.indiandentalacademy.com
  69. 69. Accessory ligaments www.indiandentalacademy.com
  70. 70. www.indiandentalacademy.com
  71. 71. Synovial membrane • Specialized fringe located at the anterior border of the retrodiscal tissues produces a synovial fluid which fills the joint cavities thus it is turned as a synovial joint. • Capsule lined on its inner surface • Membrane does not cover articular disk except for posterior bilaminar region • Consists of 2 layers 1. Cellular intima 2. Vascular sub-intima -prevents folding of membrane www.indiandentalacademy.com
  72. 72. Synovial fluid • Since articular surfaces of joint are nonvascular, the synovial fluid acts as a medium for providing metabolic nutrients to these tissues • The synovial fluid also serves as a lubricant between articular surfaces during function • Composition - dialysate of plasma with some added protein of mucin www.indiandentalacademy.com
  73. 73. BLOOD SUPPLY www.indiandentalacademy.com
  74. 74. www.indiandentalacademy.com
  75. 75. Innervatiom 4 types of receptors 1. Ruffini end organ 2. Paccini corpuscle 3. Golgi tendon organ 4. Free nerve ending www.indiandentalacademy.com
  76. 76. www.indiandentalacademy.com
  77. 77. Hiltons law www.indiandentalacademy.com
  78. 78. • To be continued TO BE CONTINUED…. www.indiandentalacademy.com
  79. 79. GOOD MORNING www.indiandentalacademy.com
  80. 80. www.indiandentalacademy.com
  81. 81. Shapes of condyle www.indiandentalacademy.com
  82. 82. TYPES OF MUSCLES • Muscle cells are mainly of three types 1. STRIATED MUSCLE a. SKELETAL OR VOLUNTARY 2. NON-STRIATED,SMOOTH OR INVOLUNTARY 3. CARDIAC MUSCLE www.indiandentalacademy.com
  83. 83. Muscle www.indiandentalacademy.com
  84. 84. www.indiandentalacademy.com
  85. 85. www.indiandentalacademy.com
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  93. 93. MUSCLES OF MASTICATION • Mastication forces The aev maximum sustainable biting force is 756N{170 pounds}. • Molar region: Biting force range 400-890N • Premolar region: Biting force range 222-445N • Cuspid region: Biting force range 133-334N • Incisor region:Biting force range 89-111N {20-55 pounds} www.indiandentalacademy.com
  94. 94. PRIMARY MUSCLES OF MASTICATION • MASSETER • TEMPORALIS • MEDIAL AND LATERAL PTERYGOID SECONDARY MUSCLES OF MASTICATION The suprahyoid group of muscles being used as secondary or supplementary muscles they are • Digastric • Mylohyoid • Geniohyoid www.indiandentalacademy.com
  95. 95. THE MASSETER • Quadrilateral and and consist of three layers. ATTACHEMENTS • Superficial Layer: Arises by thick aponeurosis. From zygomatic process of maxilla and anterior 2/3 of lower border of zygomatic arch, pass downward and back wards at an angle of 45degree and inserted into lower part of lateral surface of ramus of mandible www.indiandentalacademy.com
  96. 96. • MIDDLE LAYER: Arises from anterior 2/3 of the deep surface and posterior 1/3 of the lower border of the zygomatic arch,pass vertically downwards and and inserted into middle part of ramus. • DEEP LAYER: Arises from deep surface of the zygomatic arch, pass vertically downwards and inserted into the upper part of the ramus and into the coronoid process. www.indiandentalacademy.com
  97. 97. www.indiandentalacademy.com
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  100. 100. • Nerve supply: MASSETRIC NERVE, a branch of anterior division of mandibular nerve (which is the 3rd part of V cranial nerve- trigeminal nerve). • Blood supply: Maxillary artery, which is a branch of external carotid artery. www.indiandentalacademy.com
  101. 101. ACTIONS OF MASSETER Actions: • Elevates the mandible to close the mouth and to occlude the teeth in mastication. • Its activity in the resting position is minimal. • It has a small effect in side-to-side movement, protraction and retraction. www.indiandentalacademy.com
  102. 102. THE TEMPORALIS TEMPORAL FASCIAE • Thick aponeurotic sheet that roofs over the temporal fossa and covers the temporalis muscle . • ATTACHEMENTS • Fan shaped • Arises from whole of temporal fossa.(except the part formed by zygomatic bone) and deep surface of temporal fascia • Fibers converge and descend into a tendon . • It passes through the gap between the zygomatic arch and the side of the skull • Attached to medial surface,apex,anterior and posterior border of coronoid process and anterior border of the ramus of the mandible as far as last molar. www.indiandentalacademy.com
  103. 103. www.indiandentalacademy.com
  104. 104. www.indiandentalacademy.com
  105. 105. • BLOOD SUPPLY Deep temporal part of maxillary artery • NERVE SUPPLY Temporalis is supplied by the deep temporal branches of the anterior trunk of mandibular nerve. www.indiandentalacademy.com
  106. 106. ACTIONS OF TEMPORALIS • Elevates the mandible,this movement requires both the upward pull of anterior fibers and backward pull of the posterior fibers. • Posterior fibers draw the mandible backwards after it has been protruded. • It is also a contributor to side to side grinding movement. www.indiandentalacademy.com
  107. 107. www.indiandentalacademy.com
  108. 108. POSTERIOR FIBER DRAWS MANDIBLE BACKWARDS www.indiandentalacademy.com
  109. 109. SIDE TO SIDE GRINDING MOVEMENT www.indiandentalacademy.com
  110. 110. MEDIAL PTERYGOID ATTACHEMENTS • It is a thick quadrilateral muscle • Attached to medial surface of lateral pterygoid plate and grooved surface of pyramidal process of the palatine bone. • A more superficial slip from the lateral surface of pyramidal process of the palatine bone and tuberosity of maxilla • Its fibers pass downwards laterally and backwards • Attached by a strong tendinous lamina ,to the postero-inferior part of the medial surfaces of the ramus and the angle of the mandible • It is attached as high as mandibular foramen and as far forward as the mylohyoid groove www.indiandentalacademy.com
  111. 111. www.indiandentalacademy.com
  112. 112. • NERVE SUPPLY Branch of the main trunk of the mandibular nerve • BLOOD SUPPLY Pterygoid branch of 2nd part of maxillary artery www.indiandentalacademy.com
  113. 113. Actions of medial pterygoid • Assits in elevating the mandible • Acting with the lateral pterygoid they protrude it • Acting with medial pterygoid of same side advances the condyle ,while the jaw rotates through the opposite condyle(when the medial and lateral pterygoid of the two sides contract alternatively to produce side to side movements of mandible eg chewing) www.indiandentalacademy.com
  114. 114. Medial and lateral pterygoid act together to protrude the mandible www.indiandentalacademy.com
  115. 115. LATERAL PTERYGOID • ATTACHMENTS It is a short thick muscle with two parts or head • UPPER head arise from infratemporal surface and infratemporal crest of greater wing of sphenoid bone • LOWER head arise from lateral surface of lateral pterygoid plate. • Its fibers pass backwards and laterally to be inserted into a depression(pterygoid fovea)on the front of the neck of the mandible and into the articular capsule and disc of the temporomandibular articulation. www.indiandentalacademy.com
  116. 116. www.indiandentalacademy.com
  117. 117. www.indiandentalacademy.com
  118. 118. www.indiandentalacademy.com
  119. 119. • NERVE SUPPLY The lateral pterygoid is supplied by a branch of anterior division of the mandibular nerv • BLOOD SUPPLY Pterygoid branch of 2nd part of maxillary artery www.indiandentalacademy.com
  120. 120. ACTIONS OF LATERAL PTERYGOID • Assists in opening the mouth with suprahyoid muscle. • Slow elongation while closing the mouth with masseter and temporalis • Acting with medial pterygoid of same side advances the condyle ,while the jaw rotates through the opposite condyle(when the medial and lateral pterygoid of the two sides contract alternatively to produce side to side movements of mandible eg chewing). www.indiandentalacademy.com
  121. 121. • When the medial and lateral pterygoids of two sides act together they protrude the mandible so that the lower incisors project in front of the other. • Some authorities have ascribed different actions to the two parts of pterygoid muscle. • The upper (superior)head being involved in chewing • The inferior in protrusion,electromyographic records in rhesus monkey favors this view. www.indiandentalacademy.com
  122. 122. www.indiandentalacademy.com
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  124. 124. www.indiandentalacademy.com
  125. 125. Medial and lateral pterygoid act together to protrude the mandible www.indiandentalacademy.com
  126. 126. Secondary muscles taking part in the mastication The 4 primary muscles of mastication are in turn supported or supplemented by few secondary muscles known as SUPRAHYOID GROUP of muscles they are • DIGASTRIC • MYLOHYOID • GENIOHYOID • STYLOHYOID is other suprahyoid muscle, which does not take part in mastication www.indiandentalacademy.com
  127. 127. • DIGASTRIC- The muscle has secondary role in mastication as a depressor muscle adding to the action of lateral pterygoid muscle when mouth is to be opened against resistance. Elevation of hyoid bone • MYLOHYOID- The secondary role of this muscle is evident as a depressor seen in action when mouth is to be opened against resistance. • It elevates the floor of mouth to help in degluttition. www.indiandentalacademy.com
  128. 128. • GENIOHYOID- Geniohyoid elevates the hyoid bone and draws it forward, thus acting as a partial antagonist to stylohyoid. • When the hyoid bone is fixed, it depresses the mandible www.indiandentalacademy.com
  129. 129. Cervical Group: • Indirectly involved in mandibular function . • They are Trapezius, Sternocleidomastoid ,Anterior vertebral muscles,the lateral vertebral muscles and other deep posterior cervical muscles. • They act to stabilize head posture during the active contraction of the masticatory ,suprahyoid and infra hyoid muscles during the mastication and swallowing www.indiandentalacademy.com
  130. 130. www.indiandentalacademy.com
  131. 131. BIOMECHANICS • Complex joint system. • Compound joint – Its structure and function can be divided into 2 distinct system: • Condyle disc complex. • Condyle disc complex and articulating surface of mandibular fossa. • Constant contact between joint surfaces for stability is required. • Disc space more at rest, decreases with an increase in pressure of the joint www.indiandentalacademy.com
  132. 132. • Movement involving the joints has been divided different phases • Occlusal or rest position • Retruded opening phase or rotation • Early protrusive opening phase or functional opening • Late protrusive opening phase or translation • Early closing phase • Retrusive closing phase www.indiandentalacademy.com
  133. 133. OCCLUSAL OR REST POSITION • The rest position is the first step and involves a static jaw position • In this, the joint is in loose pack position,the connective tissue at rest • The posterior band occupies the deepest part of the mandible fossa • The intermediate zone and the anterior band lies between the condyle and posterior slope of the eminence www.indiandentalacademy.com
  134. 134. RETRUDED OPENING PHASE OR ROTATION • The condyle rotates and moves 5 to 6 mm inferior to the intermediate zone • The condyle joint surface glides forward and the medial pole of the condyle moves anterosuperiorly and the lateral pole moves posteroinferiorly • The shape of inferior compartment changes the most • The upper lateral pterygoid relaxes and the lower lateral pterygoid contracts • The posterior connective tissues is in a functional state of restwww.indiandentalacademy.com
  135. 135. EARLY PROTRUSIVE OPENING PHASE OR FUNCTIONAL OPENING • The condyle moves inferiorly and anteriorly approximately 6 to 9 mm below the intermediate zone. • The disk and the condyle experience the short anterior translatory glide • The upper and lower head of lateral pterygoid contract to guide the disk and the condyle shortly forward • The posterior connective tissues is in a functional tightning www.indiandentalacademy.com
  136. 136. LATE PROTRUSIVE OPENING PHASE OR TRANSLATION • The condyle moves inferiorly and anteriorly beneath the anterior band i.e there is full opening more, space develops in the superior compartment • The upper and lower head of Lateral pterygoid contract to guide the disk and the condyle fully forward • The posterior connective tissues tightens www.indiandentalacademy.com
  137. 137. EARLY CLOSING PHASE • The condyle translates posteriorly, about 6 to 9 mm, to the intermediate zone • There is simultaneous reduction of space posteriorly in the superior compartment www.indiandentalacademy.com
  138. 138. RETRUSIVE CLOSING PHASE • The condyle rotates superiorly but remains inferior to the posterior band • This movement reduces the space in the inferior compartment • The upper head of the lateral pterygoid contracts and The lower head of the lateral pterygoid relaxes • This tightens the mandibular attachment, and forces blood from the posterior compartments • The posterior connective tissues returns to the functional rest movements www.indiandentalacademy.com
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  141. 141. 1. Is it difficult or painful to open the mouth (e.g., yawning)? 2. Does the jaw get stuck, locked, or go out? 3. Is it difficult or painful to chew, talk, or use the jaws? 4. Do the jaw joints make noises? 5. Do the jaws often feel stiff, tight, or tired? Is there pain in or about the ears, temples, or cheeks? 6. Are headaches, neck aches, or toothaches frequent? 7. Has there been a recent injury to the head, neck, or jaw? 8. Have there been any recent changes in bite? 9. Has there been previous treatment for any unexplained facial pain or a jaw joint problem? QUESTIONAIRE www.indiandentalacademy.com
  142. 142. Examination of TMJ www.indiandentalacademy.com
  143. 143. Examination of TMJ www.indiandentalacademy.com
  144. 144. www.indiandentalacademy.com
  145. 145. MASSETER www.indiandentalacademy.com
  146. 146. TEMPORALIS www.indiandentalacademy.com
  147. 147. Lateral pterygoid www.indiandentalacademy.com
  148. 148. Measurement of mouth opening www.indiandentalacademy.com
  149. 149. To be continued…. www.indiandentalacademy.com
  150. 150. www.indiandentalacademy.com
  151. 151. Sternocleidomastoid www.indiandentalacademy.com
  152. 152. Cervical group www.indiandentalacademy.com
  153. 153. Splenius and trapezius www.indiandentalacademy.com
  154. 154. HORIZONTAL PLANE BORDER & FUNCTIONAL MOVEMENTS When mandibular movements are viewed in the horizontal plane, a rhomboid-shaped pattern can be seen that has a functional component, & 4 distinct movement components:- 1) Left lateral border 2) Continued left lateral border with protrusion 3) Right lateral border 4) Continued right lateral border with protrusion www.indiandentalacademy.com
  155. 155. Left Lateral Border Movements • With the condyles in the centric relation position, contraction of the right inferior lateral pterygoid move the right condyle - anteriorly and medially. • If left inferior pterygoid stays relaxed, with the left condyle still in the CR & result will be left lateral border movement. • Left condyle- working or rotatory Right condyle- non-working or orbiting www.indiandentalacademy.com
  156. 156. Continued Left Lateral Border Movements With Protrusion • With the mandible in the left lateral border position, contraction of the left inferior lateral pterygoid along with continued contraction of right inferior lateral pterygoid will cause the left condyle to move anteriorly to the right. www.indiandentalacademy.com
  157. 157. Right Lateral Border Movements • Left condyle-orbiting • Right condyle- rotatory www.indiandentalacademy.com
  158. 158. Continued Right Lateral Border Movements With Protrusion www.indiandentalacademy.com
  159. 159. LATERAL MOVEMENT – When lateral movement is executed the working condyle rotates & moves outward while, other non working condyle translates forward, medially downward orbiting around the rotating working condyle. – The orbiting condylar path is known as sagittal lateral condylar path. – Lateral condylar path is longer & more steep than the protrusive condylar path. www.indiandentalacademy.com
  160. 160. PROTRUSIVE MOVEMENT • condylar translations www.indiandentalacademy.com
  161. 161. Imaging • Trans-cranial • Trans-pharyngeal • Trans-orbital • OPG • SMV • Reverse-towne’s • Conventional tomography • Computed tomography • Arthrography • MRI www.indiandentalacademy.com
  162. 162. TRANS-CRANIAL www.indiandentalacademy.com
  163. 163. TRANS-CRANIAL www.indiandentalacademy.com
  164. 164. TRANS-CRANIAL www.indiandentalacademy.com
  165. 165. Diagnostic information • Lateral aspect of joint space , glenoid fossa, articular eminence, condylar head • Position of the head of condyle • Shape of glenoid fossa and articular eminence • Condition of articular surface • Gross osseous changes on the lateral aspect of condyle • Displaced condylar feacture www.indiandentalacademy.com
  166. 166. TRANS-PHARYNGEAL www.indiandentalacademy.com
  167. 167. TRANS-PHARYNGEAL www.indiandentalacademy.com
  168. 168. Trans-pharyngeal www.indiandentalacademy.com
  169. 169. Diagnostic information • Medial aspect of condyle • Erosive changes of condyle www.indiandentalacademy.com
  170. 170. TRANS-ORBITAL www.indiandentalacademy.com
  171. 171. Trans-orbital www.indiandentalacademy.com
  172. 172. Diagnostic information • Entire mediolateral dimension of articular eminence, condylar head and neck is visible • Condylar neck fractures • Morphology of convex surface of condylar head can be evaluated • Gross degenerative changes www.indiandentalacademy.com
  173. 173. OPG www.indiandentalacademy.com
  174. 174. Reverse-townes www.indiandentalacademy.com
  175. 175. Diagnstic information • Shape of the condylar head and condition of articular surface from posterior aspect • Direct comparison of both condyles • Fractures of head and neck • Condylar hypo/hyper-plasia www.indiandentalacademy.com
  176. 176. SMV www.indiandentalacademy.com
  177. 177. AP Trans-maxillary www.indiandentalacademy.com
  178. 178. www.indiandentalacademy.com
  179. 179. www.indiandentalacademy.com
  180. 180. • Linear tomography • Multi-directional hypocycloidal tomography • Multi-directional computer controlled spiral tomography www.indiandentalacademy.com
  181. 181. Advantages • Assesment of whole joint • Position of the head of condyle • Shape of the head of condyle • Information of all aspects of joint • Position and orientation of fracture fragments www.indiandentalacademy.com
  182. 182. ARTHROGRAPHY www.indiandentalacademy.com
  183. 183. www.indiandentalacademy.com
  184. 184. Computed tomography www.indiandentalacademy.com
  185. 185. Advantages • Images both hard and soft tissues • Disc condyle comlex can be evaluated • 3 D image • No physical trauma www.indiandentalacademy.com
  186. 186. MRI www.indiandentalacademy.com
  187. 187. MANDIBULAR TRACKING DEVICES • Disc displacement with reduction • Click with deviation • Exact movement of mandible can be recorded • Diagnose and monitor TMD • Sensitivity and specifity www.indiandentalacademy.com
  188. 188. Sonography • Recording and graphically demonstrating joint sounds • Audio-amplifying devices • Ultra-sound echo recordings • Specific disc derangement • No additional diagnostic information www.indiandentalacademy.com
  189. 189. Vibration analysis • Intra-capsular and internal derangement • Minute vibrations by condyle • Identifying disc displacement • Selection of appropriate patient therapy • Positve finding • Non reducing derangement www.indiandentalacademy.com
  190. 190. Thermography • Records and graphically illustrates skin temp. • Various temperatures recorded by different colors • Bilateral symmetrical thermogram • Asymmetric thermogram associated with TMD • Identifying myo-facial trigger points • Show greater variability of normal temp. In 2 sides of face www.indiandentalacademy.com
  191. 191. CLASSIFICATION I Masticatory muscle disorders 1. Protective co-contraction (11.8-4)* 2. Local muscle soreness (11.8.4) 3. Myofascial pain (11.8.1) 4. Myospasm (11.8-3) 5. Centrally mediated myalgia (11.8.2) II Temporomandibular joint disorders 1. Derangement of the condyle-disc complex • Disc displacements ( • Disc dislocation with reduction ( • Disc dislocation without reduction (11.7-2.2) 2. Structural incompatibility of the articular surfaces a. Deviation in form (11.7.1) i. Disc ii. Condyle iii. Fossa www.indiandentalacademy.com
  192. 192. b. Adhesions ( i. Disc to condyle ii. Disc to fossa c. Subluxation (hypermobility) (11.7.3) d. Spontaneous dislocation (11.7.3) 3. Inflammatory disorders of the TMJ a. Synovitis/capsulitis (U.7-4.1) b. Retrodiscitis ( c Arthritides (11.7.6) i. Osteoarthritis (11.7.5) ii. Osteoarthrosis (11.7.5) iii. Polyarthritides ( d. Inflammatory disorders of associated structures i. Temporal tendonitis ii. Stylomandibular ligament inflammation . www.indiandentalacademy.com
  193. 193. III Chronic mandibular hypomobility 1. Ankylosis (11.7.6) a. Fibrous ( b. Bony ( 2. Muscle contracture (11.8.5) a. Myostatic b. Myofibrotic 3. Coronoid impedance IV. Growth disorders 1. Congenital and developmental bone disorders a. Agenesis ( b. Hypoplasia ( c. Hyperplasia ( d. Keoplasia ( 2. Congenital and developmental muscle disorders a. Hypotrophy b. Hypertrophy (11.8.6) c. Neoplasia (11-8.7) www.indiandentalacademy.com
  194. 194. TMJ DISORDERS Classification: 1) Growth disorders and the joint • Developmental disorders. • Acquired disorders. • Neoplastic disorders. 2) Masticatory muscle disorders: • Protective muscle splinting. • Muscle hyperactivity or spasm. • Myositis (muscle inflammation). 3) Disk interference disorders (internal derangement) • Incoordination. • Deformation of articular disk. • Partial anterior disk displacement. • Anterior disk displacement with reduction. • Anterior disk displacement without reduction. • Anterior disk displacement with perforation. • Posterior disk displacement.www.indiandentalacademy.com
  195. 195. 4) Problems that result from extrinsic trauma: • Tendonitis. • Myositis. • Traumatic arthritis. • Dislocations. • Fracture. • Internal derangements. 5) Degenerative joint disease: • Arthrosis (non-inflammatory phase). • Osteoarthritis (inflammatory phase). • Osteochondritis disecans. 6) Inflammatory joint disorders: • Synovitis and capsulitis • Retrodiskitis. • Inflammatory arthritis www.indiandentalacademy.com
  196. 196. 7) Chronic mandibular hypomobility: • Ankylosis. • Fibrosis. • Contracture of elevator muscle. • Internal disk derangement. 8) Post surgical problems www.indiandentalacademy.com
  197. 197. Acc. To fricton I) Causalgic Disorders • Posttraumatic reflex sympathetic dystrophy • Causalgia II) Muscular Disorders • Myofascial pain syndrome (MPS) • Myositis • Fibromyalgia • Contracture • Recurrent spasm • Secondary to collagen disease III) Joint Disorders • TMJ capsulitis • TMJ internal derangement • TMJ ankylosis • TMJ hypermobility • TMJ degenerative joint disease Polyarthritis Infectious Traumatic Metabolic Rheumatoid www.indiandentalacademy.com
  198. 198. 1. Cervical degenerative joint disease 2. Cervical disk disorder 3. Disorder secondary to rheumatic disease www.indiandentalacademy.com
  199. 199. ALDERMAN'S CLASSIFICATION OF TMD Extracapsular 1. Psychlologic: Tension, anxiety, oral habits 2. latrogenic: Misdirected mandibular nerve block, excessive depression of mandible during anesthesia or oral procedures. 3. Traumatic: Blow to .face not involving fractures. 4. Dental: Occlusal abnormalities, periapical or periodontal lesion mobile, sensitive or damaged teeth and ulcerations. 5. Infections: Secondary or arising outside the joint. 6. Otologic: Otitis media or external ear infection. 7. Neoplastic; Parotid gland, neoplasm or tumor. www.indiandentalacademy.com
  200. 200. 1. Congenital: Agenesis, hyperplastic or hypoplastic condyle. 2. Infections: Primary bacterial infection within the joint 3. Arthritic: Rheumatoid arthritis, osteoarthritis, psoriatic arthritis, uvenile chronic arthritis 4. Traumatic: Fractures, disc tears. 5. Functional: Subluxation, dislocation, disc derangements, Hypermobility, ankylosis. 6. Neoplastic: Benign or malignant tumors. Intracapsular www.indiandentalacademy.com
  201. 201. CONCLUSION www.indiandentalacademy.com
  202. 202. THANK YOU For more details please visit www.indiandentalacademy.com www.indiandentalacademy.com