hi for the new pg people

1. GOOD
MORNING

2. SIGNIFICANCE OF MAXILLARY
DENTURE BEARING AREA AND
RELATED ANATOMY
PRESENTED BY
DR NARAYAN SUKLA
1ST YEAR PG
DEPART MENT OF PROSTHODONTIA

3. - Introduction
- bony structures
- mucous membrane
- limiting structures
- supporting structures
- relief areas
-conclusion
- reference

4. Introduction
The anatomical significance and the anatomy of the
edentulous ridge in the maxilla and mandible is
very important for the design of a complete
denture
Our objective in fabrication of a complete
denture is to provide for a prosthesis that
restores lost teeth and associated structures
functionally, anatomically and aesthetically as
much as possible with preservation of
underlying structures and the knowledge
landmarks help us in achieving our objective.

5. osseous structures
The osseous
structures not only
support the denture
but also have an
direct bearing on
impression making
procedure.
Maxillary denture is
supported by two
pairs of
bones, maxillae &
palatine bone.

Boucher pg no 148
fig

6. Mucous Membrane
Mucous membrane
serves as a cushion
between the
denture base and
supporting bone.
Mucous membrane
is composed of
mucosa and sub
mucosa.
Sub mucosa is
formed by
connective tissue
that varies from
dense to loose
areolar tissue and
varies in thickness.
------compact bon
---------periosteum
-------sub mucosa
--------mucosa

7. Mucous Membrane
Thickness and consistency of the sub mucosa
are responsible for the support that the
mucous membrane affords a
denture, because the sub mucosa makes up
the bulk of mucous membrane.
In healthy mouth the sub mucosa is firmly
attached to the periosteum of bone and will
withstand the pressure of dentures.
If sub mucosa is thin, soft tissue will be non
resilient and mucous membrane will be easily
traumatized.

9. According to the clinical significance
Landmarks
of edentulous jaws
Limiting structures
Supporting
structures
Relief areas

10. Limiting structures
These are the sites that will
guide us in having an optimum extension
of the denture so as to engage
maximum surface area without
encroaching upon the muscle actions
Encroaching upon these structures will
lead to dislodgement of the denture
and/or soreness of the area while failure
to cover the areas upto the limiting
structure will imply decreased retention
stability and support.

11. Labial frenum


It is a fold of mucous
membrane at the median line
It contain no muscle fiber
and has no action of his own
CLINICAL SIGNIFICANCE
Sufficient allowance should
be created in final impression
and in complete denture
prosthesis
 If the frenum is attached
close to the creast
frenectomy should be done
 The labial notch of the
denture should be narrow but
deep enough to avoid
interference

Labichal notch

12. Labial vestibule
Labial vestibule (sulcus)-The part of the
oral cavity which is bounded on one side
by the teeth, gingiva and residual
alveolar ridge and on the outer side by
lips. It runs from one side of the buccal
frenum of one side to the other side
;dividing in two compartments-left and
right by the labial frenum
 This area is covered by non keratinized
epithelium with areolar tissue
CLINICAL SIGNIFICANSE
 The outer surface of the labial vestibule
is the orbicularis oris.* Its fibers run in a
horizontal direction; so it has an indirect
effect on the denture base
 Reflection of the m m superiorly marks
the height
 The area of reflection has no muscle
attachment
 Due to this the tissue in this region is
movable and lead to over extension
 Overextension causes
instability/soreness.

•Labial flange

13. Buccal frenum

Single or double folds of mucous
membrane.

Broad and fan shaped.

The buccal frenum is the dividing line
between the labial & buccal vestibules.
It is related to three muscles, so it
requires more clearance than the labial
frenum

Buccal frenum-Attachment of following
muscles;levator anguli oris,orbicularis
oris,buccinator.
The caninus ( levator anguli oris)
attaches beneath and affects its
position
The orbiculeris oris pulls the frenum
forward and buccinators pulls
backward
CLINICAL SIGNIFICANCE

Moves with muscles of cheek during
speech and mastication.

During final impression and in
prosthesis clearance should be
created for the movement of the
frenum overriding will cause pain and
dislodgement of denture

During impression the cheeck should
Buccal notch

14. Buccal vestibule (sulcus)
Extends from anteriorly buccal frenum
to the hamular notch posteriorly.
Laterally by buccal mucosa, medially
by the residual alveolar ridge
 The size of the vestibule is dependant
upon- contraction of buccinator
muscle
position of the mandible
amount of bone loss
CLINICAL SIGNIFICANSE
To record maxillary buccal sulcus, the
mouth should be half way closed
The size & shape of distal end of buccal
flange depend up on movement of
ramus of mandible at the disital end of
the buccal vestibule
Hence the patient move the mandible in a
lateral protrusive relation so that
coronoid process dose not interfere
with these function
Improper extension causes
instability/soreness

Buccal flan

15. The pterygomaxillary (hamular) notch

It is depression situated between the
maxillary tuberosity and the hamulus
of the pterygoid plate .It is a soft area
of loose connective tissue.
clinical significance






Used as a boundary of the posterior
border of maxillary denture
In cases showing gross alveolar
resorption the hamular notch
disappear, so the back edge of the
denture is not carried too far
The denture border should extend till
hamular notch
Aids in achieving posterior palatal
seal area
Over extension cause soreness
Underextention cause poor retention

16. Posterior palatal seal area[post
dam]- at or along the junction of the
Soft tissue
soft and hard palate on which the
pressure within the physiological
limits of the tissue can be applied by
a denture to aid in the retention of the
denture
Made of two regions·→
1.Pterygomaxillary seal-The part of the
posterior palatal seal that extends
across the hamular notch. It extends
3-4 mm anterolaterally to end in the
mucogingival junction on the posterior
part of the maxillary ridge.
2.Posterior palatal seal-This is a part of
the posterior palatal seal area that
extends between the two maxillary
tuberosity

17. Posterior palatal seal area[post
dam]-significance
Clinical
Reduces the tendency for gag reflex due to
downward movement of the denture during
incising
 .it maintains contact of denture with soft
tissue
during functional movements of stomatognathic
system, by which it decreases gag reflex.
 . Decreases food accumulation with
adequate tissue compressibility.
 Decrease patient discomfort of tongue with
posterior part of denture.
 Compensation of volumetric shrinkage that
occurs during the polymerization
 Increases retention and stability by creating
partial vacuum.
 Increased strength of maxillary denture


18. Supporting structures
Masticatory forces produce quite a
pressure on the underlying structures
and not everyplace beneath the
denture can take such stress hence
we need to know the areas which can
bear the stresses well.
Support is the resistance to the
displacement towards the basal tissue or
underlying structures.
These can be divided into1.Primary stress bearing area
2.Secondary stress bearing area

19. Supporting structures
Primary stress bearing area
Secondary stress bearing
area
1.The horizontal portion of
1. the rugae area
the hard palate
2.maxillary tubeorcity
lateral to the
midline –posterolateral
slopes
2.Slopes of residual alveolar
ridge

20. Primary stress bearing area
These are the areas that are most
capable to take the masticatory
load providing a proper support
to the denture.
Some desired properties for
primary stress bearing area
are1.Tightly adherent sufficient fibrous
connective tissue with an
overlying keratinized mucosa
2.Presence of cortical bone cover
3.Should be at right angles to the
vertical occlusal forces.
4.No underlying structures should
be present that will get harmed
due to stress

21. Primary stress bearing area
Hard Palate
-
-
The anterior region of the hard
palate is formed by the palatine
selves of maxillary bone
The posterior part is formed by
horizontal part of palatine bone
Covered by keratinized stratified
squamous epithelium
Anterolaterally, the sub mucosa
contains adipose tissue.
Poster laterally, it contains
glandular tissue.
Clinical significance
- The horizental portion of the hard
palate provides the primary
stress-bearing area.

22. Residual alveolar ridge


The portion of the residual
bone , soft tissue covering
that remains after the
removal of teeth .
The residual ridge consist of
mucosa sub mucosa
periosteum and the residual
alveolar bone
Clinical significance


It is the foundation of
denture
It is the primary stress
bearing area

23. Secondarystressbearingare
a
rugae area
Raised areas of dense connective
tissue radiating from the median
suture in the anterior 1/3rdof
palate
It consists of series of ridges in
the anterior part of the hard
palate
Sets at an angle to residual
ridge & covered by thin soft
tissues
Clinical significanse
It is considered as a secondary
stress bearing area
Should not be distorted in the
impression.

24. Maxillary Tuberosity


It is the bulbus extension of the
residual ridge in the 2nd and 3rd molar
region
It is the distal aspects of the posterior
ridge terminating in the hamular notch
Clinical significance



The medial & lateral walls resist the
horizontal and torquing forces which
would move the denture base in
lateral or palatal direction.
Therefore, maxillary denture base
should cover the tuberosities and fill
the hamular notches.
Gross enlargement(fibrous or bony –
surgical correction.
Area of tuberosity

25. Relief area
These are the areas which either resorb
under constant load or have fragile
structures within or are covered by thin
mucosa which can be easily
traumatized
& hence should be relieved.
 Incisive
papilla
 Mid palatine raphae
 fovea palatinae

26. Incisive papilla
Incisive papilla is a mass of fibrous
tissue about 1cm behind the upper
incisors.
 It is an exit point of nasopalatine
nerves and vessels

clinical significance
Its position in the edentulous mouth
indicates where the incisors and
canines should be set.
 It should be relieved failure of which
would result in necrosis of the
distributing areas and paresthesia of
anterior palate. burning sensation
and pain.
 Denture base should be relieved over
the area to avoid pressure to the
nerves & blood vessels.


27. Mid palatine raphe

Median suture area covered by thin sub
mucosa
Extends from incisive papilla to distal end
of hard palate.
 In the region of medial palatal suture , the
sub mucosa is extremely thin ; so relief
should be provided to avoid trauma or
rocking of the denture

Clinical significance

Relief is to be provided as it is
supposed to be the most sensitive part
of the palate to pressure

Relieve adequately to avoid trauma from
denture base.
Median palatine

28. Fovea Palatina



Bilateral indentations near the midline of
palate. Posterior to junction of hard and
soft palate.
These are a pair of mucous gland duct
orifices near the midline at the junction of
the hard and soft palate.
Formed by coalescence of several
mucous gland ducts.
clinical significance


Aids in determining vibrating line.
These landmarks provide a guide to the
position of the posterior palatal border of
a denture

29. Conclusion
Thus, we see that a sound
knowledge of the anatomical
landmarks of the edentulous
jaw is a prerequisite if one
has to achieve the objective
one has in mind; fabrication of
a complete denture that has
maximum retention, stability
and support with preservation
of underlying structures with
minimum post insertion
problems.

30. References
Boucher's Prosthodontics
 Essential of complete denture prosthesis
by Sheldon Winkler
 Clinical dental prosthetics by h r b fenn


31. Thank u