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8/3/2019 Maxilla Landmarks
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Anatomical landmarks andtheir clinical significance in
Edentulous Maxillary arch
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Importance
To decide upon the distribution of forces invarious locations of the foundation area.
The dentures and their supporting tissuescoexist for a reasonable length of time.
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The ultimate support for maxillary denturecomes from the hard palate and the softtissues that increases the surface area ofthe basal seat.
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Compact bone
Adipose tissue
Sub mucosa
Mucosa
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ANATOMIC STRUCTURES
LIMITING STRUCTURE
SUPPORTING STRUCTURE
RELIEF AREAS
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LIMITING STRUCTURE
Labial frenum
Labial vestibule
Buccal frenum Buccal vestibule
Hamular notch
Posterior palatal seal area
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Supporting structures
Support is the resistance to the displacement towards
the basal tissue or underlying structures.
Primary stress bearing area /Supporting area
The horizontal portion ofthe hard palate lateral to the
midline
posterolateral slopesSlopes of residual alveolar ridge
Secondary stress bearing area /Supporting area
Rugae area set at an angleto residual ridge
Maxillary Tuberosity
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RELIEF AREAS
Incisive papilla
Mid-palatine raphe
Crest of the residual alveolar ridge Cuspid eminence
Fovea palatine
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Labial frenum:
Fold of mucous membrane atthe median line.
Moves with muscles of lip.
No muscle of its own
Action: vertical narrownotch
A- correct
contour
B
incorrect
contour.
C- area should
have been
covered.
Labial notch
LIMITING STRUCTURES
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BUCCAL FRENUM
Single or double folds of mucousmembrane.
Broad and fan shaped.
Moves with muscles during
speech and mastication.( levatoranguli oris, orbicularis oris,buccinator)
Adequate relief for muscle
activity-more clearence.
Maxillary buccal frenum area.
Denture border contour in buccal
frenum area.
Buccal notch
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Labial to buccalfrenum.
Muco-gingival line-limits upper border.
Record adequatedepth/width.
Overextension causesinstability/soreness.
Proper contouringgives optimal esthetics.
Labial flange
LABIAL VESTIBULE
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BUCCAL VESTIBULE
Buccal frenum to hamular notch.
Record adequate depth/width.
Improper extension causesinstability/soreness.
Size varies contraction ofbuccinator, position of mandible &the amount of bone lose frommaxilla.
Buccal flange
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Distal end of the buccalvestibule
Influenced by coronoid
process of mandible. This space is usually higher
than any other part of theborder.
Should be examined with themouth as nearly closed aspossible
Disto-buccal area / Corono-maxillary space
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Is a soft area of areolar tissue between
distal surface of tuberosity and the
hamular process of the medial
pterygoid plate.
Significance : it houses the disto-lateral termination of the denture
Aids in achieving posterior palatal
seal.
Overextension causes soreness.
Underextension poor retention
HAMULAR NOTCH.
Area of hamular notch
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POSTERIOR PALATAL SEAL
AREA
The soft tissue area at or beyond the junction of the hardand soft palates on which pressure within physiologicallimits, can be applied by a complete denture to aid in itsretention.
Parts Postpalatal seal Pterygomaxillary seal
Extensions Anteriorly Anterior vibrating line
Posteriorly Posterior vibrating line Laterally 3-4mm anterolateralto hamular notch.
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VIBRATING LINE
An imaginary line across the posterior partof the palate marking the division betweenthe movable and immovable tissues of thesoft palate. This can be identified when the
movable tissues are functioning.
Anterior vibrating line valsalva maneuver
ah with short vigorous bursts
Posterior vibrating line ah in short bursts in a normal, unexaggerated
fashion.
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Hard palate
Support for themaxillary denture.
Primary stressbearing area-horizontal portion ofhard palate lateral to
midline.
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Residual alveolar ridge
The portion of theresidual bone , softtissue covering that
remains after theremoval of teeth .
Important supportarea subjected to
resorption.Alveolar groove
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Rugae
Raised areas ofdense connectivetissue radiating fromthe median suture inthe anterior 1/3rd ofpalate .
Secondary stressbearing area.
Should not bedistorted in theimpression.
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MAXILLARY TUBEROSITIES.
Are distal aspects ofthe posterior ridgeterminating in thehamular notch
Grossenlargement(fibrousor bonysurgical
correction.
Area of tuberosity
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Incisive papilla pad offibrous connectivetissue over the incisiveforamen.
Location :behind andbetween the centralincisors
Relief necessary -burning sensation andpain.
Indication of resorption.
INCISIVE PAPILLA
Incisive fossa
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Extends from incisivepapilla to distal end ofhard palate.
Thin mucosal coveringand non-resilient..
Relieve adequately toavoid trauma from
denture base.
Mid palatine raphae.
Mid palatine groove
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Fovea Palatinae
Bilateral indentationsnear the midline of palate.
Formed by coalescence ofseveral mucous glandducts.
Posterior to junction ofhard and soft palate.
Always on soft palate
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Labial frenum.
Shorter and widerthan the maxillary
frenum. Adequate relief for
muscle activity(mentalis).
Proper fit around itmaintains sealwithout soreness.
Mandibular arch.
Labial notch.
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Buccal frenum.
Adequate relief formuscle activity.
Proper denture seal.
Buccal notch
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Labial vestibule. Labial-buccal frenum.
Overextension causesinstability/soreness.
Muscles attachmentclose to the crest of theridge- limits the dentureflange extension.
Mucolabial fold limitsthe depth of the flange.
Record adequate depth
and width. Proper contouring gives
optimal esthetics.Labial flange
B l ib l
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Buccal vestibule.
Buccal frenum-retromolar pad.
Record adequate
depth and width. Impression is widest
in this area.
Buccal flange
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Buccal shelf
Extends from buccal frenumto retromolar pad.
Between external obliqueridge and crest of alveolar
ridge. Primary stress bearing
area(cortical bone)- lies atright angles to vertical
occlusal forces.
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External oblique ridge.
A bony ridge runsantero-posteriorlyoutside the buccal
shelf. Denture border 1-2
mm beyond this ridge.
Shows as Groove inimpression.
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Alveolar ridge
Residual bone withmucous membrane.
Crest to be relieved.
Buccal and lingualslopes are secondarystress bearing areas.
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Retromolar pad.
Triangular soft pad oftissue.
Posterior end of loweredentulous ridge.
Limiting landmark ofdistal extension ofcomplete denture uptoant 2/3 rd of retro molarpad.
Determines height andwidth of the occlusaltable.Retromolar fossa
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Alveolo-Lingual sulcus.
Between lingual frenum toretromylohyoid curtain.
Anterior region- lingualfrenum to mylohyoid ridge.
Premylohyoid fossa-premylohyoid eminence inimpression.
Border of Impression tomake contact with the
mucosa of the floor of themouth when tonguetouches the upper incisor.
Overextension causessoreness and instability.
Lingual flange
Premylohyoid
eminence
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Middle region.
From pre-mylohyoidfossa to the distalend of the mylohyoidridge.
Lingual flangeextends below thelevel of the
mylohyoid ridge-tongue rests on thetop of flange andaids in stabilizing the
lower denture.
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Posterior region.
The flangepasses into theretromylohyoidfossa.
Proper recordinggives typical Sform of the
lingual flange.
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Retromylohyoid space.
Distal end of lingualsulcus.
Area posterior to the
mylohyoid muscle. Good seal aids in
retention and stability.Retromylohyoid eminence
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Mylohyoid ridge.
Attachment for themylohyoid muscle.
Sharp or irregular
covered by themucous membrane.
Trauma from denturebasereliefnecessary.
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Mylohyoid muscle.
Floor of the mouth isformed by mylohyoidmuscle.
Lies deep to thesublingual gland in theanterior region- does notaffect the border ofdenture.
Posterior regionaffectsthe lingual border inswallowing and tonguemovements.
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Lingual frenum.
Fold of mucousmembrane.
Base of tongue to
supragenial tubercle. Registered in
function.
Lingual notch