MIDTERM I: Intro Radiology + Perio Anatomy Flashcards
what is CBCT
cone beam computed tomography
what is the ALARA principle
as low as reasonably achievable or attainable - using discretion/ as low radiation as possible used
what is resorption?
loss of dentin and cementum due to osteoclasts (normal in primary teeth as there is a tooth coming up, but pathological in secondary) aka root resorption -can be internal (mid root) or apical (end of root)
what should a diagnostic PA show
-root apex and at least 2 mm beyond the root -incisal edge of the tooth -open contacts (when possible) (periapical, peri=around, apex=highest point)
trauma in mandible
red- tooth 9, chipped or missing restoration
white- tooth 10, internal resorption
orange- tooth 10 , external apical root resorption
white- tooth 11, impacted
Y line of ennis (inverted y line)- made by floor of nasal cavity and border of maxillary sinus
soft tissue of the nose
Incisive foramen (or nasopalatine foramen/ anterior palatine foramen)
median palatine suture
nutrient canals
blue- genial tubercles (bony protuberance)
green: lingual foramen
mental ridge (protuberance on labial /anterior mandible)
pink: zygomatic process of the maxilla
red: maxillary sinus
green: zygoma (zygomatic bone)
yellow: maxillary tuberosity
blue: coronoid process of the mandible
pink: zygomatic process of the maxilla
red: maxillary sinus
green: zygoma (zygomatic bone)
yellow: maxillary tuberosity
blue: coronoid process of the mandible
what is the yellow spot and what tooth is above it
mental foramen below tooth 29 (mandible)
green: submandibular fossa (on lingual surface of mandible)
pink: external oblique ridge (on facial surface of mandible)
blue: myohyoid ridge (on lingual surface of mandible)
green: submandibular fossa
pink: external oblique ridge
what should a diagnostic BW show
- alveolar bone level in the maxilla and mandible
- open proximal contacts between adjacent teeth
- distal surface of canine (premolar BWs) and distal of last fully erupted molar (molar BWs)
what is gutta percha
used for root canals
what is lamina dura
thin layer of dense/ cortical bone that lies adjacent to the PDL in the tooth socket. radiopaque lining around pdl space
how does the pdl appear on a radiograph? (radiolucent or radiopaque)
radiolucent
which step of ODTP process is hard tissue exam?
step 3
what is involved in a hard tissue exam
- thorough visual exam using a mirror
- tactile exam using a pigtail explorer
- radiographic images up on the computer
what is best for finding interproximal caries
bitewing radiographs
what could radiolucency around crown margin mean
open crown margin/ recurring caries, or radiographic “burnout”, or Mach bands/Mach effect
what are the 1. simple and 2. specific radiographic descriptions for radiolucency at the end of a root?
- simple description: periapical radiolucency
- specific radiographic description: rarifying osteitis
what is cervical burnout
or radiographic burnout- darkening around cej can occur, may appear like root caries but you will see caries in multiple images
how can a radiograph show periodontal disease
- loss of alveolar bone height on bitewing images
- loss of crestal cortical bone (difference?)
- widening of the PDL space
calculus
what is the crown to root ratio
crown (clinical)– so its incisal or occlusal to bone surface. and root is bone level to apex.
red- gold or zirconium crown
green- porcelain fused metal crown
left are porcelain fused metal crowns and root canals.
right shows ceramic crowns and root canals
what is the epithelium lining the gingival sulcus called
crevicular epithelium
where does keratinized tissue end in gingiva
at the mucogingival junction
what is the epithelium that connects the CT to the tooth
junctional epithelium- first attachment and bottom of the crevice
what is the gingiva made up of
overlying stratified squamous epithelium and underlying connective tissue core
how do you know gingiva is healthy
color , contour (gingival margins-knife edge), consistency, no bleeding upon probing
-stippled surface indicates health but not always there
where should gingiva attach to the tooth
on enamel, above CEJ, its the junctional epithelium that attaches
what lies below the attached gingiva?
alveolar mucosa
what is the epithelial ridge and what does it come into contact with
squigly line of epithelium , comes into contact with inner connective tissue, projections of that are called connective tissue papilla
top purlpe is stratum corneum. next is stratum granulosum - black dots in that are keratohyalin granules (melanin)
next green/red are stratum spinosum layer
-next is stratum basale. the white dots in between are desmosomes. the black dots at the bottom are hemidesmosomes.
– top two layers are MISSING when non keratinized!
what is in between the enamel and the attached gingiva?
dental pellicle. ?
what are the internal and external basal laminas
internal basal lamina is the lining of epithelium that touches the tooth (enamel and cementum), and the external basal lamina is the lining that touches the connective tissue core
what is another term for gingival connective tissue? what is it made up of (%s)
LAMINA PROPRIA!
- collagen fibers (60%)
- fibroblasts (5%)
- vessels, nerves and matrix (35%)
what type of collagen fibers are in gingival connective tissue- what is their role
what are the groups
type I collagen fibers!
-they brace marginal gingiva firmly against tooth (dentogingival unit), provide rigidity to withstand forces of mastication.
3 groups of collagen fibers in gingiva: gingivodental, circular (wrap around tooth), and transseptal (connecting tooth to tooth interdental)
what is ‘Col’
depression/dip below the contact point of the tooth on proximal sides, gingiva forms papilla tips . dip goes down in the middle and up (papilla) on facial and lingual ends)
-if loss of attachment or not connecting at all/correctly i think there is no col
what is the PDL made up of, what are the parts that connect to bone/tooth called? what is the average width? what are the angles ?
collagenous principal(?) fibers arranged in bundles
- inserted into cementum and bone via sharpey fibers (terminal ends)
- average width is .2 mm
- fibroblasts, osteoblasts, nerve and vascular network around
- grouped into horizontal (towards crown), oblique (middle region of root), and apical(bottom of root)
what is the group of pdl fibers that is in the furcation space?
interradicular
what is the PDL functions
- soft tissue protection for vessels and nerves from injury
- transmission of occlusal forves to bone
- attachment of tooth to bone
- resistance to impact of occlusal forces (shock absorption)
what are the two types of cementum
acellular (primary)- covers cervical third to half of root
cellular (secondary) found towards the apical third of the root
what are the components of the alveolar process
- external plate of cortical bone
- alveolar bone proper - inner socket wall of thin compact bone (lamina dura)
- cancellous bone
- radicular bone is part that extends up (?)
what are the functions of the alveolar bone
mostly PROTECTION, SUPPORT, and calcium metabolism
what is typical form of bone near teeth (mandible./maxilla
- thin bony margins
- vertical grooving
- positive architecture
what are dehiscence and fenestrations
dehiscences: loss of alveolar bone on the buccal or lingual of a tooth that is CONTINUOUS with bony margin
fenestration: “WINDOW” loss of alveolar bone on buccal or lingual that is not continuous with bony margin, just a window
what is the suprabony defect
the alveolar crestal bone goes down horixontally
what is the intrabony defect
vertical loss of alveolar bone
which teeth have furcations
maxillary molars, mandibular molars, maxillary first premolars (CHECK THIS THO!)
what is supracrestal connective tissue
just the inner connective tissue of gingiva!
where should the gingival margin be for healthy gums?
AT , OR coronal to CEJ! in gingivitis it would probably be coronal
what should a healthy probing depth be
1-3 mm
how is junctional epithelium attached to tooth? does JE have ridges?
usually at CEJ, by hemidesmosomes!!
NO RIDGES!!
how far is alveolar crest to the base of JE/CEJ?
alveolar crest (bone crest) is about 2 mm apical to base of JE or CEJ
where might you expect the gingival margin to be in gingivitis
coronal to cej, so the depth will be larger. you normally have very close to cej
what occurs with gingivitis
- No loss of attachment to the bone
- the junctional epithelium proliferates and extends epithelial ridges into the connective tissue (???)
- supragingival fiber bundles have been destroyed (reversible!)
- cementum is not exposed
what may occur with periodontitis with respect to gingival margins, pocket depth, symptoms. what is permanently damaged?
gingival marigns could be apical or coronal to the CEJ, Pocket depth is often greater than or equal to 4 mm due to apical migration of junctional epithelium. mobility of teeth may occur. PAIN is NOT common!
-CEMENTUM is exposed in the pocket!! periodontal pocket provides an ideal environment for growth of bacteria now.
– coronal part of JE detaches and thereby, the apical portion moves apically, making larger pocket
-PERMANENT bone loss and destruction of PDL fibers
