BOARDS cephs, radiographs, superimpositions Practice
Questions | 2024
anterior cranial base landmarks, and how does the length affect skeletal AP
classifications? **** ACB length - sella-nasion, tells you position of maxilla
increased ACB=more class II, usually nasomaxillary complex more down and forward in
this scenario
decreased ACB=more class III, usually nasomaxillary complex more up and backward
in this scenario
posterior cranial base landmarks, and how does the length affect skeletal AP
classifications? **** PCB - sella-basion (or articulare), tells you position of mandible
and glenoid fossa
increased PCB=more class III (longer means rotating mandible forward)
Ceph history
broadbent
tweed
downs
steiner **** broadbent-invented 1931
tweed-diagnosis/analysis
downs-frankfort
steiner-SN
what is the avg difference between SN and Frankfort? **** 7 degrees
facial axis **** basion-nasion line to foramen rotundom-gnathion line
avg is 90
<90 = retrognathic chin
>90 = prognathic chin
DOES NOT change throughout life
part of Ricket's analysis
facial angle **** FH line to Nasion-Pogonion line
avg is 88
***INCREASES with age usually 8-18 years old***
(fay-ayng = ayty ayt degrees)
angle of convexity **** Nasion-Apoint-Pogonion
avg is 0
-negative is concave is class III
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, -positive is convex is class II
holdaway ratio **** measurement in MM to determine lower incisor to symphysis
ratio is 1:1 (4mm-4mm)
GET FIGURE FOR THIS
broadbent registration landmarks **** used for Downs superimposition (Doadbent)
Bolton-Nasion line, and line perpendicular to sella
bolton point is highest point of convavity posterior to occipital condyle
Prosthion **** aka superior prosthion, aka supradentale
most inferior/anterior point on maxillary process (usually seen just above CEJ of U1)
Tweed triangle **** FMA - Frankfort mand plane angle (25; 16-28)
FMIA - Frankfort mand incisor angle (FMIA; 68)
IMPA - incisor mand plane angle (90-95)
Opisthion **** posterior border of foramen magnum
Kilovoltage peak (kVp)
how does kVp affect contrast?
if you wanted to see a root fx, would you increase or decrease kVp?
does increasing exposure time increase penetration? **** measure of penetration
(kvP=Penetration)
increasing kVp decreases contrast
root fx-decrease kVp (higher contrast)
exposure time does not affect penetration
mA
how does mA affect contrast? **** tube current, amount or quantity of x-rays
produced (mA=Amount)
increase mA = increase contrast and # xrays produced
density of a radiograph
how does distance affect density?
how does kVp, mA, or exposure time affect density? **** (kVp x mA x sec)/L
increased distance = less density
increasing any of these increase density
what effect does decreasing voxel size have on radiation? **** increases radiation
and higher dose exposure
how far should the lateral ceph source be from midsaggital plane of pt?
how far should the lateral ceph film be from the midsaggital plane of pt? **** SOD -
60 inches, 5 feet
For help with assignments, discussions, research papers, Ms. excel and ppt tasks contact
Questions | 2024
anterior cranial base landmarks, and how does the length affect skeletal AP
classifications? **** ACB length - sella-nasion, tells you position of maxilla
increased ACB=more class II, usually nasomaxillary complex more down and forward in
this scenario
decreased ACB=more class III, usually nasomaxillary complex more up and backward
in this scenario
posterior cranial base landmarks, and how does the length affect skeletal AP
classifications? **** PCB - sella-basion (or articulare), tells you position of mandible
and glenoid fossa
increased PCB=more class III (longer means rotating mandible forward)
Ceph history
broadbent
tweed
downs
steiner **** broadbent-invented 1931
tweed-diagnosis/analysis
downs-frankfort
steiner-SN
what is the avg difference between SN and Frankfort? **** 7 degrees
facial axis **** basion-nasion line to foramen rotundom-gnathion line
avg is 90
<90 = retrognathic chin
>90 = prognathic chin
DOES NOT change throughout life
part of Ricket's analysis
facial angle **** FH line to Nasion-Pogonion line
avg is 88
***INCREASES with age usually 8-18 years old***
(fay-ayng = ayty ayt degrees)
angle of convexity **** Nasion-Apoint-Pogonion
avg is 0
-negative is concave is class III
For help with assignments, discussions, research papers, Ms. excel and ppt tasks contact
, -positive is convex is class II
holdaway ratio **** measurement in MM to determine lower incisor to symphysis
ratio is 1:1 (4mm-4mm)
GET FIGURE FOR THIS
broadbent registration landmarks **** used for Downs superimposition (Doadbent)
Bolton-Nasion line, and line perpendicular to sella
bolton point is highest point of convavity posterior to occipital condyle
Prosthion **** aka superior prosthion, aka supradentale
most inferior/anterior point on maxillary process (usually seen just above CEJ of U1)
Tweed triangle **** FMA - Frankfort mand plane angle (25; 16-28)
FMIA - Frankfort mand incisor angle (FMIA; 68)
IMPA - incisor mand plane angle (90-95)
Opisthion **** posterior border of foramen magnum
Kilovoltage peak (kVp)
how does kVp affect contrast?
if you wanted to see a root fx, would you increase or decrease kVp?
does increasing exposure time increase penetration? **** measure of penetration
(kvP=Penetration)
increasing kVp decreases contrast
root fx-decrease kVp (higher contrast)
exposure time does not affect penetration
mA
how does mA affect contrast? **** tube current, amount or quantity of x-rays
produced (mA=Amount)
increase mA = increase contrast and # xrays produced
density of a radiograph
how does distance affect density?
how does kVp, mA, or exposure time affect density? **** (kVp x mA x sec)/L
increased distance = less density
increasing any of these increase density
what effect does decreasing voxel size have on radiation? **** increases radiation
and higher dose exposure
how far should the lateral ceph source be from midsaggital plane of pt?
how far should the lateral ceph film be from the midsaggital plane of pt? **** SOD -
60 inches, 5 feet
For help with assignments, discussions, research papers, Ms. excel and ppt tasks contact
