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Normal Radiographic Anatomy-
Based on Intraoral Films
TeethSupporting structureMaxillaMandible Restorative Materials
WWC
Normal Radiographic Anatomy
TEETH
Enamel, dentin, cementum, Pulp, root canal Enamelodentin junction C-E junction Normal and developing
Cervical burnout
WWC
Normal Radiographic Anatomy
Developing tooth
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Normal Radiographic Anatomy
SUPPORTING STRUCTURE
Lamina dura
Alveolar crest
Periodontal ligament space
Cancellous bone
WWC
Normal Radiographic Anatomy
SUPPORTING STRUCTURE
Lamina dura
Thin R-O (radiopaque) shadow bounding the sound tooth socket
Wider & more dense in teeth of heavy occlusion
WWC
Normal Radiographic Anatomy
Double lamina dura … in root with two eminences (buccal & lingual).
Intact apical lamina dura …. a vital pulp.
WWC
Normal Radiographic Anatomy
Alveolar crest R-O line between teeth, gingival mar
gin of the alveolar process, cortical border of the alveolar bone.
A point of bone in ant. teeth ; flat in post.
CEJ to alveolar crest ...< 1.5mm Recede apically with age Markable resorption with periodonta
l disease Continuing with lamina dura and for
ms a sharp angle → Rounding angle indicative periodontal disease
WWC
Normal Radiographic Anatomy
Periodontal ligament space
R-L (radiolucent) space between root & lamina dura
Width of PDL varied by individual, teeth & location; thinner in the middle of the root, slightly widened near the alveolar crest & apex ….fulcrum of physio logical movement of a tooth
Double PDL space ...created by the shape of the tooth.
WWC
Normal Radiographic Anatomy
Cancellous bone (trabecular bone or spongiosa)
Thin R-O plates & rods (trabeculae) surrounding many small R-L pockets of marrow.
In ant. maxilla : fine, granular & dense pattern, the marrow spaces are small and numerous.
In post. maxilla : trabecular similar to ant. maxilla, slightly larger in marrow spaces.
WWC
Normal Radiographic Anatomy
In ant. Md.: thicker trabeculae , coarser pattern; more horizontally oriented and fewer trabecular plates, larger marrow space.
In post. Md. : larger marrow space than ant. Md.,horizontally oriented trabecular plates and fewer trabeculae number below the apices of Md. molars.
The distribution & size of the trabeculae show a reversal relationship to the thickness (and strength) of the cortical plate.
Cancellous bone
WWC
Normal Radiographic Anatomy
MAXILLA Intermaxillary suture Anterior nasal spine Nasal fossa Incisive foramen Sup. foramina of the nasopal
atine canal Lateral fossa (Nose) Nasolacrimal canal Maxillary sinus Zygomatic process and zygo
matic bone (Nasolabial fold) Pterygoid plates
WWC
Normal Radiographic Anatomy
Intermaxillary suture (median palatal suture) A R-L line in the midline of the Mx. from alveolar crest between central in
cisors superiorly through ant. nasal spine , continues posteriorly the Mx. palatine processes to the post. aspect of hard palate.
Limited by two R-O borders of thin cortical bone in each Mx A small rounded or V-shaped enlargement R-L at the alveolar crest .
WWC
Normal Radiographic Anatomy
Anterior nasal spine On periapical film of the maxillary cent
ral incisors. In the midline; about 1.5 ~ 2 cm above t
he alveolar crest, at or below the junction of the inf. end of the nasal septum and inf. outline of the nasal fossa
V-shaped R-O .
WWC
Normal Radiographic Anatomy
Nasal fossa
R-L image on intraoral radiograph of maxillary teeth
The inferior border appears as a R-O line extending bilaterally away from the base of the anterior nasal spine.
WWC
Normal Radiographic Anatomy
Nasal septum R-O image arising in the mid
line from the ant. nasal spine , is a superimposition of septal cartilage & vomer bone.
Inferior nasal concha From lateral wall toward the
septum
WWC
Normal Radiographic Anatomy
Incisive foramen (nasopalatine or anterior palatine foramen)
R-L image between roots of the central incisors
Oral terminus of the nasopalatine canal transmits the nasopalatine vessels & nerves ; approximately the junction of the median palatine & incisive sutures.
Incisive canal cyst : enlargement of the foramen & canal , > 1cm
WWC
Normal Radiographic Anatomy
Superior foramina of the nasopalatine canal
Two R-L areas above the apices of the central incisors in the nasal cavity floor, on both sides of the septum, round or ovoid shape
WWC
Normal Radiographic Anatomy
Lateral fossa (incisive fossa) A gentle depression in the maxilla near the
apex of the lateral incisor→ diffusely R-L
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Normal Radiographic Anatomy
Nose Superimposed on the anterior
maxilla A slightly opaque appearance
with sharp border
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Normal Radiographic Anatomy
Nasolacrimal canal Near apex of the canine Steep vertical angulation
in periapical radiograph Routinely seen on maxilla
ry occlusal projection in molar region . Lesser palatine
foramina
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Normal Radiographic Anatomy
Maxillary sinus An air-filled cavity with mucosa lining Three-sided pyramid, base & the media
l wall adjacent to nasal cavity, apex extending laterally into zygomatic process of Mx.
(1) superior wall –the floor of the orbit
(2) anterior wall—extending above the premolar
(3) posterior wall—bulging above molar & tuberosity
Bilateral symmetry
WWC
Normal Radiographic Anatomy
Thin R-O line near apices of upper premolars & molars
Enlarge during children , until 15-18y/o , may change during adult life in response to environmental factors (ex. missing teeth)
In puberty, the floors of the Mx. sinus & nasal cavity may be present at the same level, and may extend farther into the alveolar process in older age, below the nasal cavity floor in the post. region of Mx.
WWC
Normal Radiographic Anatomy
Inverted “Y” in the canine or premolar region in the periapical radiographs.
Roots apices may cause small elevations into the floor of the sinus. Lamina & floor of the sinus may fuse as a thin layer of bone covering the apex.
WWC
Normal Radiographic Anatomy
Nutrient canals or grooves –
Thin R-L lines of uniform width within lateral sinus wall, accommodate the posterior superior alveolar v. and superior alveolar n.
Septa—folds of cortical bone projecting away from the floor and wall of the antrum, usually vertically oriented . Complete septa did infact divide the sinus into individual compartment in 1-10% .
Bony nodules—A normal variant of the floor of the maxillary sinus, homogenous R-O, with trabeculation , and blend with adjacent bone.
WWC
Normal Radiographic Anatomy
Zygomatic process and zygomatic bone
WWC
Normal Radiographic Anatomy
Zygomatic process and zygomatic bone Zygomatic process of the Mx:
Extension of lateral Mx. surface, arises in the apical area of the 1st & 2nd molar, articulation for the zygomatic bone.
“U” shaped R-O line on the periapical radiographs.
The inferior part of the zygomatic bone extends posteriorly from infer. border of the zygomatic process of Mx, a uniform gray or white R-O over the apices of molars .
WWC
Normal Radiographic Anatomy
Nasolabial fold
An oblique line on the periapical radiographs of the premolar region, and the area of increased R-O is posterior to the line .
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Normal Radiographic Anatomy
Pterygoid plates Medial & lateral pterygoid pl
ate lie immediately posterior to the tuberosity , almost always cast a single R-O homogenous shadow without evidence of trabeculae if apparent on the intraoral film
Hamular process : extends downward from the medial pterygoid plate.
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Normal Radiographic Anatomy
MANDIBLE Symphysis Genial tubercle Mental ridge Mental fossa Mental foramen Mandibular canal Nutrient canals Mylohyoid ridge Submandibular gland fossa External oblique ridge Inferior border of mandible Coronoid process
WWC
Normal Radiographic Anatomy
MANDIBLE
Symphysis In infant, a R-L line through
the midline of the jaw The suture usually fuses by t
he end of the first year of life, then no longer radiographically apparent.
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Normal Radiographic Anatomy
Genial tubercle (mental spine) Spine shaped bony protuberances Midline lingual surface of the mandib
le, above the inferior border. Well visualized on standard Md. occlu
sal film as one or more projections; as a R-O mass (3-4mm in diameter) in the midline below the incisor roots.
Lingual (spinous) foramen : A small R-L dot surrounded by the cortical wall of the termination of incisive branch of mandibular canal.
WWC
Normal Radiographic Anatomy
Mental ridge R-O lines sweeping bilaterally fo
rward and upward toward the midline on periapical film of the Md. central incisors.
Mental fossa A R-L depression on the anterio
r surface of the mandible between the alveolar ridge and mental ridge.
WWC
Normal Radiographic Anatomy
Mental foramen Anterior limit of the inferior d
ental canal on the radiographs. Round, oblong, slitlike or very
irregular and partial or completely corticated.
Between the lower border of the mandible and the alveolar crest, usually in the apex of the 2nd premolar.
WWC
Normal Radiographic Anatomy
Mandibular canal A dark linear shadow with thin
R-O superior and inferior borders cast by the lamella of bone that bounds the canal
Apparent between the mandibular foramen & the mental foramen and may close contact with all molars and 2nd premolar.
WWC
Normal Radiographic Anatomy
Nutrient canals R-L lines of fairly uniform width with
hyperostotic borders Running vertically from the inf. denta
l canal to the apex of tooth or into the interdental space between Md. incisors.
Visible in 5 % patients, esp. in blacks, males, older persons, and individuals with high blood pressure or advanced perio. disease.
WWC
Normal Radiographic Anatomy
Mylohyoid ridge (Internal oblique ridge) A bony crest on lingual su
rface of the mandibular body, attachment of mylohyoid muscle.
Running downard and forward from the area of 3r
d molar to premolar at the level of apices.
WWC
Normal Radiographic Anatomy
Submandibular gland fossa
A depression immediately below the mylohyoid ridge in molar region, above the inferior border of the mandible
Accommodates the submand. gland → a R-L area with sparse trabeculae , poorly defined anter. & posteriorly
WWC
Normal Radiographic Anatomy
External oblique ridge A continuation of the ant. border
of ramus → a line of attachment of buccinator m.
A R-O line near the alveolar crest in the mandibular 3rd molar region.
Inferior border of mandible A dense, broad, R-O band
WWC
Normal Radiographic Anatomy
Coronoid process Frequently apparent o
n periapical film of the maxillary molars region
A triangular R-O, with apex directed superiorly & anteriorly.
WWC
Normal Radiographic Anatomy
RESTORATIVE MATERIALS
Complete R-O : silver amalgam, gold, silver points R-O : stainless steel pins, calcium hydroxide base , gutta-percha stainless steel crown, orthodontic appliance R-L : silicates, composite , porcelain
WWC
Normal Radiographic Anatomy
WWC
Normal Radiographic Anatomy