Maxillary Edentulous Anatomy

Importance ..

To decide upon the distribution of forces in various locations of the foundation area

Foundation areas ,are the areas that are going to withstand the load of mastication, we have to decide which areas of the maxilla even the mandible that are going to be loaded We mean by Loaded the occlusal load

The dentures and their supporting tissue coexist for a reasonable length of time

When you construct a complete denture for a patient, the patient has to come every six months to one year to check the underlying tissue beneath the dentures, because of continuous loading during function, phonetics ..,there will be load on the residual ridge and this load will transfer to the bone which is the foundation of the denture

The load will cause exploration of the process of resorption (no resorption)

Unfortunately our old patients , when we construct the denture to them ,they don’t attend to check up which is a wrong idea …we have to see what is going on with the underlying tissue

For example in a case a patient didn’t attend for check up , after 6 years the residual ridge and the dentures walls were rolling around inside the patient mouth ,there were no ridge to set up

Because After a while these dentures need relying layers by adding extra layers made of acrylic material that are going to substitute the amount of resorption ,otherwise they will end up with poor retention

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Here is the maxillary bone The important land marks , the incisal foramen and ,, the incisal papilla which is important (to demarcate the mid line when we set our upper anterior teeth) we have the maxillary tuberosity We have also Hamular notch which demarcates a posterior border of the denture The vibrating line which separates between the hard tissue and soft tissue The ultimate support for maxillary dentures comes from the hard palate and the soft tissues that increases the surface area of the basal seat

This is a histological slide .. It shows the composition of bone

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Anatomic Structures

o Limiting structures, that will limit our nature extension o Supporting structures ,that will support o Relief areas, the areas that shouldn’t be subjected to load

because the soft tissue is width..any pressure will cause trauma to this tissue and the patient will not be able to wear the denture

Limiting Structures

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Labial frenum.. this attach the upper lateral with the residual ridge it presents in the labial part in the anterior part of the mouth ,it presents in the upper and lower jaw It’s important to create a V shape notch while making a flange to make this tissue free of movement otherwise the denture will fall down while pulling the denture outside the mouth

Labial vestibule (sulcuses) to which the flange of the denture extends

Buccal frenum.. Similar to the labial frenum but in a different position,in the buccal area against the molar teeth , it separates the labial and buccal vestibule .

Again it’s important to create the V shape notch or the denture will fall from the side ,when you pull the cheek up and down this is called border molding ,When we are going to make an impression and then examine later on the denture which is the trial denture inside the patient mouth.

Buccal vestibule Hamular notch …demarcates the posterior border of the upper

maxillary gingival Posterior palatal seal area, in this area we create the post-dam

of the complete denture, this important because when we press the denture up ,the air presents between the denture and soft tissue is going out there will make a negative pressure so it will retain in position , if the post- dam(which is the last line of our maxillary denture) is small it will not compress the tissue between the hard palate and the soft palate and the denture will fall when the patient open his mouth

“Keep in mind” you might be asked about them in the oral exam

Supporting structures

Support is the resistance to the displacement towards the basal tissue or the underlying structures

It means resistance of the denture of falling down

We have …

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o Primary stress bearing area The first areas that are going to be subjected to the occlusal loading

The horizontal portion of the hard palate lateral to the mid line –posterolateral slope

Slopes of residual alveolar ridge

o Secondary stress bearing area Ruage area –set at an angle to residual ridge Maxillary tuberosity

Relief areas

The areas that we are not going to subject them to load, we have to create a space from the soft tissue of the denture and the soft tissue itself mostly created by using wax

Incisive papilla Mid-palatine raphe Crest of the residual alveolar ridge Cuspied eminence (elevation) Fovea palatine

Labial frenum

Fold of mucous membrane at median line Moves with the muscles of lip No muscles of its own Action ,vertical –narrow notch

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- the extension of the flange of our denture

A-correct counter

B-incorrect counter (very low)

C-area should have been covered to become retentive

This is a final impression

We have the labial notch, the buccal frenum notches also the vibrating line

Notice there is a roundation of the flange of the denture this is called border molding this is done by pulling the cheek and the lips outward and downward in a round movement

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Buccal frenum

Single or double folds of mucous membrane Broad and fan shaped Moves with muscles during speech and mastication (levator anguli

oris , orbicularis oris,buccinators) Adequate relief for muscle activity-more clearance

o Maxillary buccal frenum area o Denture border contour in buccal frenum area

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Again this is the final impression

The material that we use in the final impression is zinc oxide ugenol

Labial vestibule Labial to buccal frenum Muco-gingival line limits the upper border(we call it the sulcus of the

vestibule) on the denture it’s going to be filled with the labial flange Record adequate depth-width Overextension causes instability sorness Proper countering gives optimal esthetics

Under countering means short

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Over countering means extended ,this means that we are going to make pressure on the limiting areas and these areas will move when muscles move and its going to break the seal and the denture will fall

Flange is the extension of the denture to the sulcus

Buccal vestibule

Which is going to be filled with buccal flange

Buccal frenum to hamular notch Record adequate depth-width Improper extension causes instability , soreness Size varies contraction of buccinator , position of mandible & the

amount of bone lose from maxilla

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Here is also the final impression

This black like represents the denture ,and the underneath is the soft tissue

Here is the Distal end of buccal vestibule Influenced by coronoid process of the mandible

This area is Important to be produced ,when we are making a denture we ask the patient to open his mouth as wide as possible the denture shouldn’t fall ,when the denture falls down then there is something wrong

This space is usually higher than any other part of the border Should be examined with the mouth as nearly closed as possible

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Hamular notch

Is a soft area of areolar tissue between distal surface of tubrosity and the hamular process of the medial pterygoid

Significance, it houses the disto lateral termination of the denture Aids in achieving posterior palatal seal Overextension causes soreness

Soreness means the redness inflammation because of pressure in the area

Under extension –poor retention, and falling down

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Concentrate here

Posterior palatal seal area

The soft tissue area or at beyond the junction of the hard and soft palates on which pressure within physiological limits, can be applied by a complete denture to aid in its retention ,because on this area we are going to put a small elevation called a post-dam

Parts..

Postpalatal seal Pterygomaxillary seal

Extensions

Anteriorly.. Anterior vibrating line Posteriorly..Posterior vibrating line Laterally.. 3-4 mm anterolateral to humular notch

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Vibrating line

an imaginary line across the posterior part of the palate marking the division between the movable and the immovable tissues of the soft palate ,this can be identified when the tissue is functioning

this line can be identified by telling the patient to open his mouth and saying ah several times

Anterior vibrating line.. valsalva maneuver “ah” with short vigorous bursts

Posterior vibrating line.. “ah” in a short bursts in a normal ,unexaggerated fashion

Hard palate

Support for the maxillary dentures

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Primary stress bearing area – horizontal portion of hard palate lateral to midline

Residual alveolar ridge

The portion of the residual bone ,soft tissue covering that remains after the removal of the tooth

Important support area subjected to resorption

Rugae

o Raised area of dense connective tissue ,radiating from the median suture in the anterior third palate

o Secondary stress bearing area o Should not be distorted in the impression (it shouldn’t change its

position because it will create extra pressure )

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Maxillary tubrosities

Are distal aspects of the posterior ridge terminating in the hamular notch Gross enlargement (fibrous or bony –surgical correction)Sometimes there are enlargement in these area ,so in this case we subject the person to surgery to reduce this fibrous tissue

Incisive papilla

Incisive papilla ,pad of fibrous connective tissue over the incisive foramen

Location, behind and between the central incisors Relief necessary burning ,sensation and pain

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Relief necessary because we don’t want any pressure on the sensitive tissue underneath like incisive artery ,incisive vein and insicive nerve

Indication of resorption

Mid palatine raphae

Extends from incisive papilla to distal end of hard palate Thin mucosal covering and non-resilient Relieve adequately to avoid trauma from denture base

Why we always say trauma and we need relief in these areas ?!Our complete denture is made of hard material, this hard material will press a soft tissue between, the other hard material is the bone and this tissue is with ultimate contact with the underlying there’s not resiliency ,so when we press it ,it can’t run away from the pressure

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Fovea palatinae

Bilateral indentations near the midline of palate Formed by coalescence of several mucous gland ducts Posterior to junction of hard and soft palate Always on soft palate In fact it doesn’t give any important to our denture because its

posterior

The Dr said you can every Thursday watch the lab demos,he also said that we have an oral exam from five and the practical exam

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from fifteen , and he advised every chapter you have to return to the book .

ع'ظ%يم"ا “ ع'ل'ي*ك' الل-ه% ض*ل0 ف' ”. و'ك'ان'

Done By :Alaa Adas ;)

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