Lecture 7 Flashcards
TYPES OF JOINTS
FUNCTIONAL CLASSES
- ) SYNARTHROTIC - NOT MOVEABLE (I.E. FIBROUS SUTURES)
- ) AMPHIARTHROTIC - SLIGHTLY MOVEABLE (I.E. VERTEBRAE)
- ) DIARTHROTIC - MOVEABLE JOINT (I.E. SYNOVIAL JOINT)
EXAMPLES OF JOINTS
SYNARTHROTIC -
FIBROUS SUTURE - BONY *INTERDIGITATIONS, BOUND BY DENSE FIBROUS TISSUE
*GOMPHOSIS - BINDS TEETH IN ALVEOLAR BONE SOCKET (CONSISTS OF ALVEOLAR BONE, PDL, ROOT)
BONY FUSION SYNOSTOSIS - FRONTAL SUTURE OF FRONTAL BONE AND EPIPHYSEAL LINES OF MATURE BONE ARE SYNOSTOSES (METOPIC)
DIARTHROTIC - LOCATED AT THE ENDS OF LONG BONES
*TMJ - LOCATED BETWEEN TEMPORAL AND MANDIBULAR BONES
TMJ
GINGLYMOARTHRODIAL JOINT - ALLOWS JAW TO HINGE OR SLIDE SIDE TO SIDE
GINGLYMUS - HINGE JOINT
ARTHRODIAL - SLIDING JOINT
OPEN JAW VS. CLOSED JAW AND TMJ POSITION
OPEN - CONDYLE FORWARD, DISKS SLIDE FORWARD
CLOSED - CONDYLE FITS IN SOCKET ALONG W/ DISKS
TYPES OF TMJ MOVEMENTS
- ) ELEVATION (JAW CLOSING)
- ) DEPRESSION (JAW OPENING)
- ) PROTRUSION (FORWARD)
- ) RETRACTION (BACKWARD)
- ) LATEROTRUSION (SIDEWAYS)
SYNOVIAL CAPSULE MOVEMENTS
UPPER - MOVES DURING PROTRUSION (LATERAL PTERYGOID ASSISTED BY MEDIAL PTERYGOID) AND RETRACTION (POSTERIOR FIBERS OF TEMPORALIS, DEEP PART OF MASSETER, GENIOHYOID AND DIGASTRIC)
LOWER- MOVES DURING ELEVATION (TEMPORALIS, MASSETER, MEDIAL PTERYGOID) AND DEPRESSION (GRAVITY, DIGASTRIC, GENIOHYOID, AND MYLOHYOID MUSCLES)
TMJ STRUCTURAL FEATURES
ARTICULAR DISK - FOUND IN STERNOCLAVICULAR JOINT AS WELL
COMPOSED OF FIBROCARTILAGENOUS TISSUE
SYNOVIAL DISK DIVIDES INTO UPPER/LOWER CAVITY BY ARTICULAR DISK
CONDYLAR SURFACE - FIBROUS CONNECTIVE TISSUE
CONDYLAR SURFACE FEATURES
FIBROUS CONNECTIVE TISSUE => 2˚ CARTILAGE –> PROLIFERATIVE ZONE (CHONDROGENIC => GROWTH OF CONDYLE) –> HYPERTROPHIC ZONE –> OSSEUS TISSUE
TMD SIGNS AND SYMPTOMS
PAIN OF THE JOINT PAIN UPON MOVEMENT TRISMUS (SPASMS) MANDIBULAR DEVIATION POPPING CLICKING CREPITIS (FRICTION BETWEEN BONE AND CARTILAGE) FACIAL PAIN, MYALGIA, PAIN ON OPENING
MAXILLARY DEVELOPMENT
FORMS FROM ANTERIOR MESENCHYME AND FUSES W/ MESENCHYME CELLS FROM 1ST BRANCHIAL ARCH (FORMS MAXILLARY PROCESS)
MESENCHYMAL CONDENSATION OCCURS IN ANTERIOR PORTION OF THE DEVELOPING HEAD AND MIGRATES DOWN TO OVERLAP W/ STOMODEUM OVER TIME
=> DOWNWARD PROJECTION CALLED THE FRONTO-NASAL PROCESS (FNP)
FNP INTERACTS W/ MAXILLARY PROCESS AT 4 WKS IN UTERO => MAXILLA
MAIN BULK FORMATION OF MAXILLA
PAIRED MAXILLARY PROCESSES - DEVELOP FROM CRANIAL PART OF 1ST BRANCHIAL ARCH
PAIRED MANDIBULAR PROCESSES - DEVELOP FROM CAUDAL PART OF 1ST BRANCHIAL ARCH (FORMS 1ST FOLLOWED BY MAX. PROCESSES)
OSSIFICATION OF THE MAXILLA
IM OSSIFICATION BEGINS AT THE OSSIFICATION CENTERS (APPEAR WHERE ANTEROSUPERIOR DENTAL NERVE BRANCHES FROM INFERIOR BRANCH OF INFRAORBITAL NERVE)
BONE SPREADS FROM CENTER…
POSTERIORLY - BELOW ORBIT TO DEVELOPING ZYGOMA
ANTERIORLY - TOWARD FUTURE INCISOR REGION
SUPERIORLY - TO FORM FRONTAL PROCESSES OF THE MAXILLA
SECONDARY OSSIFICATION CENTERS LOCATED
AT ZYGOMATIC, NASOPALATINE, AND ORBITONASAL AREAS
OSSIFICATION SPREADS TO PALATINE PROCESS TO FORM HARD PALATE
TYPES OF CARTILAGE
MAXILLA = MEMBRANOUS VISCEROCRANIUM (CONTACTS SPHENOID, ETHMOID - BOTH = CARTILAGENOUS NEUROCRANIUM
HYOID BONE = CARTILAGENOUS VISCEROCRANIUM (*REMEMBER, FORMED FROM REICHERT’S CARTILAGE)
DEVELOPMENT OF THE PALATE
POSTERIOR SURFACE OF THE MAXILLA OSSIFICATION PROCESSES FOR THE FORMATION OF THE PALATE ARE FORMING - STARTS AT POINTS ON THE POSTERIOR AND INFERIOR SIDE OF THE MAXILLA THAT FORM BONY PLATES THAT BECOME A MAJORITY OF THE PALATE