Anatomical Landmarks Flashcards
What3 things of a complete denture depens on the bases close adaptability to the anatomic structure alllowing them to function without displacing the prosthesis
- Retention
- Support
- Stability
The ____ the denture the more retention
Wider= more retention
What are the 3 surfaces of a complete denture?
- Impression/ intaglio surface
- Polish surface
- Occlusal surface
What surface?
rests on the residual ridges and transmits forces directly to the denture-bearing tissues;
impression or intaglio surface
What surface?
made up of the labial, buccal, lingual, and palatal parts of the denture base material together with thenon-articulating buccal and lingual parts of prosthetic teeth surfaces
Polihsed surface
What surface?
consists of the teeth’s articulating surfaces which make contact during most functional and parafunctional activities.
Occlusal Surface
The denture base rests on the ____, which serves as a cushion between the denture base and the supporting bone
mucous membrane
generally have thicker mucosa and/or underlying bone that is less subject to resorption because it is cortical bone.
Primary Stress Bearing Areas
What bone is less subject to resorbtion?
Cortical Bone
Primary Stres bearing areas
The residual ridge, made up of cancellous bone and is subject to resorptive remodeling after dental extraction and with long-term denture wear.
secondary stress-bearing area
What bone makes up the residual ridge?
Cancellous Bone; resorbs
What are the 4 stress bearing areas on maxilla?
- Primary firm tuberosity
- Primary hard palate on either side of palatal raphe
- Secondary alveolar ridge
- Secondary Rugae
What are the 3 stress bearing areas on mandible?
- Primary Buccal Shevles
- Primary retromolar pads (distal to 2nd/3rd molars)
- secondary alveolar ridge
Compare area of support on mandible and maxilla
total area of support larger on maxilla
What is the size of the denture bearing area on the mandible?
14cm cube
What is the size of the denture bearing area on the maxilla?
24cm cubed
The ____ is less capable of resisting occlusal forces
Mandible less resistant
14cm
The shape and size of the ____ is dependent on the anatomic contour of the patient’s dentate arch.
Residual alveolar ridge
U, V, Square
When is resorbtion of the residual ridge the greatest?
During the first 6-12 months post extraction.
Continues at a reeduce rate throughout life
What are 7 factors that influnce the form and size of supporting bone?
- Original size prior to ext
- Severity of perio disease
- Amont of alveoloplasty (bone removal at ext)
- Forces from surroundng m.
- Forces from wear of dental prosth
- Time as edentulous
- Genetics/physioloic pre-despostion to bone resorb
What 3 things can occur is the the pt has been edentulous for many years to the residual ridge?
- Resorbs
- Crest of ridge may lack a smooth corticol bone
- Large spicules
Because the maxillary anterior alveolar ridge is ____, the resorption of the ridge creates a smaller maxillary prosthetic base.
proclined, so smaller base for maxilla
mandibular dentition is positioned significantly ____ to the basal bone of the mandible
lingual
Since the mandibular dentition is positoned lingually, the residual ridges creates a denture bearing area that is more ____ postion with a ____ and ____ mandibular prosthetic base
Denture bearing are is more buccal with flatter & wider mandibular prosthetic base
How can you slow the resorbtive process?
By creating a dentrue that fits properly
In what direction was the does the maxilla resorb?
Up and back
what class is this ridge relationship?
Class 3 ridge, extensive loss of facial support
On both max and man the residual ridge is a ____ supporting area
Secondary!!!
The ____ of the ridges are
covered in the final denture, give stability against lateral displacement and create
the peripheral seal.
lateral walls covered
* Stability
* Seal
The mucous membrane is composed of what 2 things?
- mucosa
- submucosa.
formed by connective
tissue that varies in character from dense to loose and also varies considerably in thickness.
Submucosa
The submucosa may contain glands, fat, or muscle fibers and transmits the blood and nerve supply to the ____
Mucosa!
Where does attachment of the mucous membrane to bone occur?
Betweent the submucosa & periosteum
The mucosa covering the hard palate and the crest of the residual ridge
Masticatory Mucosa
The masticatory mucsoa has well defined ____ epitheluum and demonstrates what?
- Well defined kertinized epithelium
- Lack of tissue movement
These ridge crestal tissues are remnants of the gingival tissues are what stress bearimg area?
Secondary Strss bearing areas
As the mucous membrane extends from the crest along the slope of the residual
ridge to the vestibular reflection, it loses what?
firm attachment to the underlying bone
Firm on crest loose on sulcus
The mucous memebrane on the sulcus is ?
- Nonkeratinized or slighlty epithelium
- loose connnective tissue & elastic fibers
- irritated easliy, does not withstand forces well.
What occurs to tongue when edentulous for a while?
It swells with resorbtion, into neutral zone
Maxilla
What is #12?
Incisive Papilla
maxilla
The nasopalatine nerves and blood vessels pass through the foramen, and care should be taken that the denture base does not impinge on them
Incisive Foramen
What structure maxilla?
- Dense fibrous connective tissues with minimal compressibility.
- Provide considerable support to the denture.
- # 7
Tuberosities
Primary stress bearing area
If maxillary teeth remain unopposed, the tuberosities and posterior alveolar arch can ____ below the occlusal plane, interfering with placement of the mandibular prosthetic dentition.
hypererupt, may need to be srugically removed
Hard bony enlargement in the midline of
the roof of the mouth.
* Small % pt.
* covered by thin mucous memebrane easy trauma
* disrupt retention
* May be surgically reduced if disrupting paletal seal can grow back
Torus Palatinus
What are the 3 limiting areas of the maxillary denture ?
- Labial vestibule
- Buccal vestibule
- vibrating line
Max landmark
runs from one buccal frenum to the other on the labial side of the ridge
Labial Vestibule
bilaterally In btwn the Buccal and lingual frenum
Bilaterally, extends from the buccal frenum to the hamular notch
Buccal Vestibule
Maxillary landmark?
extends from one hamular notch to the other across the palate
Vibrating Line
maxillary landmark?
the distal limit of the buccal vestibule; it is situated between the tuberosity and the hamulus of the medial pterygoid plate.
The Hamular Notch
Can be palpated with a mirror
Maxillary landmark?
Marks the beginning of motion in the soft palate when an individual says “ah,” and the soft palate elevates.
Vibrating Line
Anterior to the line is no movment
What are the 3 areas top to bottom
- Buccal Frenum
- Zygomatic Area
- Retro-zygomatic area
What mandibular landmark
area between the mandibular buccal frenum and the anterior edge of the masseter muscle.
Buccal Shelf
Primary Stress Bearing area
What kind of bone makes up the buccal shelf? How does it lie in relation tp the occlusal forces?
Dense cortical bone , its lyes at s right angle to the verticle occulusal forces
Primary Stress Bearing
How far does the mandibular denture border normally extend?
1-2mm beyond the oblique ridge
Mandibilar landmarks
an oblique ridge on the lingual surface that serves as
the boney attachment of themylohyoid muscles
Mylohyoid ridge
How far should the base of the mandibular denture extend pass the mylohyoid ridge on the lingual?
What can result from over extension?
4-6mm beyond
Overextensuon can cause the denture to lift up when the tongue lifts up.
What mandibiular landmark?
Located distal to the third molar region and is
composed of fibrous connective tissue.
Retromolar pad
primary stress bearing
What 3 muscles attach at the distal portion of the retromolar pad area?
simulate the pad and prevent it from resorbing
Pad used as landmar for the occlusal plane
- Temporalis
- Buccinator
- Masseter
The mandibular dentruee should cover how much of the pad?
2/3 of the pad
Namr all left to right
- Retromolar pad
- Buccal shefl
- Lingual vestibule
- labial vestibule
- lingual frenum
- retromylohyoid area
Mandibilar landmarks
Space distal to the mylohyoid
muscle.
Retromylohyoid fossa
What are the anterior, lateral, medial, and posterior medial boarders of the tongue?
- **mylohyoid muscle **on the anterior
- retromolar pad laterally,
-
muscles of the floor of the mouth
posteromedially - tongue medially.
Mandibular landmark
located above the mylohyoid muscle.
* Serves as the border of the denture
base in the sublingual region
* soft & reseliant will not lift denture or be traumatized
* Absorbs impact of mastication on the mucosa
Sublingual gland area
Mandibular landmarks
This area is bordered by the
* Orbicularis oris
* Mentalis muscles.
* Limit depth of labial vestibule, must not be inpined up, can displace denture
Labial flange area
Mandibular landmarsk
Membrane attachment for support of the lower lip. It must not be impinged upon
Inferior labial frenum
Mandibular landmarks
Membrane attachment for support. Must not be
impinged upon by the denture base.
Lingual Frenum
Mandibular muscles
functions to
protrude the tongue.
Genioglossus muscles
Mandibular landmarks
The boney origins of the genoiglossus/geniohyoid muscles and are often covered by the denture base to aid the peripheral seal
Genial Tubercles
Can be palapated on severely resorbed mandibles
mandibular landmarsk
Below the alverolar ridge, anteriorly where the mental nerve exits.
- ridge resobrtions can cause it to be at the crest and therefore compressed on by denture, cause pain and altered sensation of lip
Mental Foramen
Mandibular landmakr
- Lingual bilateral prominences of dense
cortical bone in the premolar area - May extend posterior to the molar area.
- May be covered with keratinized non-mobile
tissue or nonkeratinized tissue that may be
mobile - Thin friable easily irritated tissues
Mandibular tori
Can be surgicalluy removed if inpinging, can grow back
Mandibular tori is common in what kind of patients?
Bruxors because contant stimulation of bone
