anatomical landmarks of maxilla

1. ANATOMICAL LANDMARKS
OF MAXILLA
Dr. Shweta Thomas

2. MUCOUS MEMBRANE
• Composed of mucosa and submucosa
• The denture base rests on the mucous membrane which serves as a cushion
between the base and the supporting bone
• Mucosa is classified as :
• Masticatory
• Specialised
• Lining

3. Masticatory mucosa-
• mucosa covering the hard palate and crest of the residual ridge
• It is formed by keratinised stratified squamous epithelium and a
thin layer connective tissue lamina propria
Specialised mucosa- It covers the dorsal surface of the tongue
and is keratinized
Lining mucosa- It is nonkeratinised and it covers
lips,cheeks,sulcus,soft palate,ventral surface of tongue, and
slopes of residual ridge

4. Submucosa
• Formed by connective tissue
• It makes up the bulk of mucous membrane
• The support and stability depends on the thickness of
submucosa and its attachment to the underlying bone
• A dense firmly attached submucosa will successfully
withstand the pressure of the denture
• A thin layer can be easily traumatised
• A loosely attached layer is easily displaceable

5. LIMITING STRUCTURES
Labial frenum
Labial vestibule
Buccal frenum
Buccal vestibule
Hamular notch
Posterior palatal seal area

6. SUPPORTING STRUCTURES
PRIMARY STRESS BEARING AREA
Hard palate
Posterolateral slopes of residual alveolar ridge
SECONDARY STRESS BEARING AREA
Rugae
Maxillary tuberosity
Alveolar tubercle

7. RELIEF AREA
• Incisive papilla
• Cuspid eminence
• Mid-palatine raphe
• Fovea palatina

8. LIMITING STRUCTURES
They determine and confine the extent of the denture
• LABIAL FRENUM
 It is a fibrous band covered by mucous membrane that
extends from the labial aspect of the residual ridge to the
lip
 It has no muscle fibers
 Hence it is a passive frenum
 A v-shaped notch should be recorded during impression
making to accommodate the labial frenum

9. LABIAL VESTIBULE
• It is defined as the portion of the oral cavity
which is bounded on one side by the teeth,
gingiva and alveolar ridge(in the edentulous
mouth the residual ridge)and on other side by
the lips and cheeks
• The vestibule is covered by lining mucosa

10. BUCCAL FRENUM
• The buccal frenum seperates the labial
and buccal vestibule
• It attaches:
 levator anguli oris-attaches
beneath the frenum
orbicularis oris –pulls the frenum in
forward direction
 buccinator-pulls the frenum in
backward direction
• These muscle influences the position of
the buccal frenum hence it needs greater
clearance on the buccal flange of the
denture

11. BUCCAL VESTIBULE
• Is the area from the distal portion of the buccal
frenum to the hamular notch posteriorly.
• This space may be actual or potential and if a space
(postmalar pocket) exists it should be filled.
• The size of buccal vestibule varies with:
Contraction of buccinators
Amount of bone loss in the maxilla

12. HAMULAR NOTCH
• It is depression situated between the maxillary
tuberosity and the Hamulus of medial pterygoid plate.
• It is soft area of loose areolar tissue.
• The distolateral border of denture base rests in the
hamular notch.
• The denture border should extend till the hamular
notch.

13. POSTERIOR PALATAL SEALAREA(POSTDAM)
• It is defined as the soft tissue at or along the junction of
the hard and soft palate on which pressure within the
physiological limits of the tissues can be applied by a
denture to aid in the retention of the denture.
• This is the area of the soft palate that contacts the
posterior surface of the denture.
• It prevents air entry between the denture base and the
soft palate.
• It is the area between the anterior and posterior vibrating
line

14. Functions:
Aids in retention
Reduces the tendency for gag reflex
Prevents food accumulation
Compensates for polymerisation shrinkage
It can be divided into two regions based upon anatomical
landmarks
Pterygomaxillary seal
Postpalatal seal

15. PTERYGOMAXILLARY SEAL
This is the part of posterior palatal seal that extends across the
hamular notch(pterygomaxillary notch) and it extends 3-4 mm
anterolaterally to end in the mucogingival junction on the posterior
part of maxillary ridge.
The posterior extent of the denture in this region should end in the
hamular notch and not extend over the hamular process as this can
lead to severe pain during denture wear.

16. POSTPALATAL SEAL
This is a part of posterior palatal seal that extends between
the two maxillary tuberosity

17. The points should be remember while recording the
posterior palatal seal
The posterior border of the denture should not be
placed over the mid palatine raphe or the posterior
nasal spine
If there is a palatine torus which extends
posteriorly the tori should be removed
The position of fovea palatina also influences the
position of posterior border of denture.it can
extend 1-2mm across the fovea palatina

18. If a mid palatine fissure is present then the pps
should extent into it to obtain a good
peripheral seal
In patients with thick ropy saliva the fovea
palatina should be left uncovered or else the
thick saliva flowing between the tissue and
denture can increase the hydrostatic pressure
and displace the denture

19. DIFFERENT FORMS OF POSTERIOR PALATAL SEAL
(WINLAND AND YOUNG)
According to shape:
• Single bead scribed on the posterior vibrating line
• Double line scribed in the anterior and posterior
vibrating line
• Butterfly shaped pps
• Butterfly shaped pps with notching of posterior
vibrating line
• Butterfly shaped pps with notching of hamular notch

20. Variations used with different shaped soft palate based on
the classification
• Class I-a butterfly shape pps with 3-4mm width
• Class II-pps is narrow with 2-3mm of width
• Class III-a single beading made on the posterior
vibrating line

21. VIBRATING LINE
• The imaginary line across the posterior part of the palate
marking the division between the movable and immovable
tissues of the soft palate which can be identified when the
movable tissues are moving
• It marks when the individual says “ah”
• It extends from one hamular notch to other

22. • It passess about 2 mm infront of the fovea
palatina
• This line should lie on the soft palate
• The distal end of the denture must cover the
tuberosities and extend into hamular notch.it
should end 1-2mm posterior to the vibrating
line.

23. There is a presence of two vibrating lines:
1. Anterior vibrating line
2.Posterior vibrating line

24. ANTERIOR VIBRATING LINE
• An imaginary line lying at the junction between the
immovable tissues over the hard palate and the slightly
movable tissues of the soft palate.
• The anterior vibrating line is cupid bow shaped
• Due to the projection of posterior nasal spine ,the
anterior vibrating line is not a straight line between
both hamular process
• It can be located by asking the patient to perform
”Valsalva maneuvar” or by asking the patient to say
“ah” in short vigorous bursts.
• Valsalva maneuvar : the patient is asked to close his
nostrils firmly and gently blow through his nose.

25. POSTERIOR VIBRATING LINE
• An imaginary line is located at the junction of the soft
palate that shows limited movement and the soft palate
that shows marked movement
• The posterior vibrating line is an imaginary line at the
junction of aponeurosis of the tensor veli palatine
muscles and the muscular portion of the soft palate
• It is recorded by asking the patient to say “ah”in short
but normal vigorous fashion
• This line is usually straight

26. PRIMARY STRESS BEARING AREA
• HARD PALATE
1. The horizontal portion of hard palate lateral to the
midline act as primary supporting area
2. The trabecular pattern of bone is perpendicular to
the direction of force making it capable of withstanding
any amount of force
SUPPORTING
STRUCTURES

27. RESIDUAL RIDGE
• Defined as the portion of alveolar ridge and its soft tissue
covering which remains following the removal of teeth
• It resorbs rapidly following extraction and continue
throughout life in a reduced rate
• The submucosa over the ridge has adequate resiliency to
support the denture

28. SECONDARY STRESS BEARING AREA
RUGAE
• These are mucosal folds located in the anterior region
of palatal mucosa
• The folds of mucosa play an important role in speech
• Metal denture base reproduces this contour making it
very comfortable for patient

29. MAXILLARY TUBEROSITY
• It is bulbous extention of the residual ridge in the2nd
and 3rd molar region
• The posterior part ridge and the tuberosity are most
important parts of support because they are least likely
to resorb.

30. RELIEF AREAS
1. INCISIVE PAPILLA
• It is a midline structure situated behind the central incisors
• It is the exit point of nasopalatine nerves and vessels
• It should be relieved if not the denture will compress the
vessels or nerves and lead to necrosis of distributing areas
and paraesthesia of anterior palate

31. MIDPALATINE RAPHE
• It is the median suture area covered by a thin
submucosa
• This area is the most sensitive part of the
palate to pressure

32. FOVEA PALATINA
• The fovea is formed by the coalescence of the ducts of
several mucous glands
• This act as an arbitrary guide to locate the posterior
border of the denture
• The secretion of the fovea spreads as a thin film on the
denture through by aiding in retention
• In patients with thick ropy saliva the fovea palatina
should be left uncovered or else the thick saliva flowing
between the tissue and the denture can increase the
hydrostatic pressure & displace the denture

33. CUSPID EMINENCE
• It is a bony elevation on the residual alveolar
ridge formed after extraction of the canine
• It is located between the canine and 1st
premolar region

34. TORUS PALATINUS:
If the torus extends to the bony limits of
the palate leaving little or no room to place
the posterior border seal then its removal is
indicated

35. PALATAL THROAT FORM
HOUSE’S CLASSIFICATION
Class I-the soft palate is almost horizontal curving gently downwards
ClassII-the soft palate turns downwards at about45 degree angle from
the hard palate
ClassIII-the palate turns downwards sharply at about 70degree angle to
the hard palate

36. MUSCLES OF PALATE
Palate consists of 5 paired muscles
1. Tensor veli palatini muscle
2. Levator veli palatine muscle
3. Palatopharyngeus muscle
4. Palatoglossus muscle
5. Muscle of the uvula

37. TENSOR VELI PALATINI MUSCLE
• ORIGIN:
a) lateral side of auditory tube
b) adjoining part of the base of the skull
• INSERTION:
Pterygoid Hamulus ,passes through the origin of buccinator and
flattens out to form palatine aponeurosis
• ACTIONS:
Tightens the anterior part of soft palate ,opens the auditory tube to
equalize the air pressure between the middle ear and the
nasopharynx

38. LEVATOR VELI PALATINI
• ORIGIN:
a) medial aspect of auditory tube
b) adjoining part of inferior part of petrous temporal bone
• INSERTION:
It is inserted into the upper surface of palatine aponeurosis
• ACTION:
a) elevates soft palate and closes the pharyngeal isthumus
b) opens the auditory tube

39. MUSCULOUS UVULAE
• ORIGIN:
 Posterior nasal spine
 Palatal aponeurosis
• INSERTION:
 Mucous membrane of uvula
• ACTION:
 Pulls up the uvula

40. PALATOGLOSSUS
• ORIGIN:
Oral surface of palatine aponeurosis
• INSERTION:
a) descends in the palatoglossal arch
b) side of the tongue at the junction of its oral and pharyngeal parts
• ACTION:
a) Pulls up the root of the tongue
b) Approximate the palatoglossal arch
c) Closes the oropharyngeal isthumus

41. PALATOPHARYNGEUS
• ORIGIN:
Anterior fasciculus-posterior border of hard palate
• INSERTION:
a) Posterior border of the lamina of thyroid cartilage
b) wall of the pharynx and its median raphe
• ACTION:
Pulls up the wall of the pharynx and shortens it during swallowing

42. REFERENCE:
1.BOUCHER
2.WINKLER

43. THANK YOU