Libyan International Medical University - Removable Prosthodontics
Anatomical and Physiological Considerations in the
Maxilla and the Mandible
 Extra-Oral Landmarks
 Intra-Oral Landmarks
–
Maxillary Anatomical Landmarks
–
Mandibular Anatomical Landmarks
 Border Structures that limit the Periphery of the Denture
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Maxillary
–
Mandibular
EXTRA-ORAL LANDMARKS
1. Naso-Labial Fold
2. Philtrum
3. Angle of the mouth
4. Modiolus
5. Vermillion Border
6. Wet Line
7. Mento-Labial Sulcus
Mandible
The only moving part of the stomatognathic system. It consists of a single bone. The body of the
mandible is horse-shoe shaped and carries the alveolar process.
The distal portion of each side continues upward and backward into the mandibular Ramus.
The ramus divides superiorly into condylar and coronoid process
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INTRA ORAL LANDMARKS
Anatomical Landmarks in the Maxilla
Maxillary Denture Supporting Structures
1. Residual Alveolar Ridge
2. Incisive Papilla.
3. Rugae.
4. Mid Palatine Raphe.
5. Hard Palatal Vault
6. Soft Palate.
7. Maxillary Tuberosity.
Residual alveolar ridge
Incisive papilla
Rugea area
Midpalatine Raphe
Hard palate
Tuberosity
Soft palate
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The Residual Alveolar Ridge
The alveolar process arise from the body of each maxilla. They consists of two parallel
plates of cortical bone –buccolinual or labiolingual which unite behind the last molar tooth
to form the maxillary tuberosity.
The Incisve Papilla
The Incisve Foramen is located in the midline of the palate, slightly to the palatal side of the
anterior palatal alveolar plate.
Nasopalatine nerves and vessels exit the foramen to the palate at right angles to the margins
of the bony fossa.
The fossa is covered by a protective pad of fibrous connective tissue called the
‘Incisive Papilla’; the denture base must be relieved to avoid pressure on these sensitive
nerves.
Failure to relieve denture base will result in pressure on the nerves and vessels resulting in
reduced blood supply & nerve irritation (burning symptoms).
The Rugae
These are irregularly shaped ridges of connective tissues covered by the mucous membrane
in the anterior third of the hard palate
The Mid-Palatine Raphe
The suture that joins the two palatine processes at the midline is called the Mid-palatine
Suture. This suture is covered by a thin, dense mucoperiosteum with little or no submucosa.
Its position in the palate is marked by a raised area of the mucous membrane called the ‘MidPalatine Raphe’. Because of the lack of adequate submucosa, this region is also considered
as a relief area.
The Hard Palatal Vault
The hard palatal vault is the base for the maxillary denture. This Hard Palatal Vault is
composed of two pairs of bones,
-the Maxillae and,
-the Palatine bones.
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The Soft Palate
This is the moving soft tissue part posterior to the hard palate. It vibrates during various
functional movements. The posterior vibrating line is always in the soft palate.
The Maxillary Tuberosity
The posterior surface of the maxillary body ends inferiorly as a convexity termed the
maxillary tuberosity.
An overhanging tuberosity (Pendulous Tuberosity) can cause problems.

It may interfere with location of occlusal plane and reduces the space available for
posterior teeth arrangement.

Teeth are NOT set on the tuberosity region.
Pendulous Tuberosity
Maxillary Denture - Limiting Structures
1. Labial frenum.
2. Labial vestibule.
3. Buccal frenum.
4. Buccal vestibule.
5. Hamular notch.
6. Fovea palatinae
7. Anterior Vibrating lines.
8. Posterior Vibrating lines.
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Buccal Frenum
Labial Vestibule
Buccal Vestibule
Fovea Palatini
Antr.
Vibrating
Line
Hamular Notch
Postr. Vibrating Line
The Hamular Notch
The area between the pterygoid hamulus and the Maxillary Tuberosities is a depression the ‘Hamular Notch.
It is critical to the design of the Maxillary denture, as the hamular notch is part of the
posterior extension of the maxillary complete denture.
The Fovea Palatini
They are the openings of certain minor salivary glands in the soft palate. They are always
seen close to the midline, and are useful in locating the posterior vibrating line.
The Vibrating Lines
These are imaginary lines drawn to identify an area in the soft palate called the ‘Posterior
Palatal Seal Area’.
There are two imaginary lines
–
the Posterior Vibrating line- It is almost always a gentle curve, which passes through
the Hamular Notch to form the posterior-most extension of the Maxillary Denture.
–
the Anterior Vibrating line- It is the line more anterior to the posterior vibrating line
which gives the posterior palaltal seal area the Cupid’s bow shape.
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Anterior
Vibrating Line
Fovea Palatini
Hamular Notch
Posterior Palatal Seal Area
Postr. Vibrating Line
Anatomical Landmarks of the Mandible
The only moving part of the stomatognathic system. It consists of a single bone. The body of the
mandible is horse-shoe shaped and carries the alveolar process.
The distal portion of each side continues upward and backward into the mandibular Ramus.
The ramus divides superiorly into condylar and coronoid process
Mandibular Denture Supporting Structures
1. Alveolar Ridge
2. Retro molar pad
3. External Oblique Ridge
4. Buccal Shelf Area
5. Mental Foramen
6. Mylohyoid Ridge
7. Genial Tubercles
8. Torus Mandibularis
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The Residual Alveolar Ridge
The alveolar processes arise from the body of the mandible. They consists of two parallel
plates of cortical bone –buccolinual or labiolingual which to form the residual alveolar
ridge. The alveolar ridge ends posteriorly in front of the Retro Molar Pad or the Pear-Shaped
Pad.
The Retro-Molar Pad (Pear-Shaped Pad)
This is a pear shaped pad seen distal to the residual alveolar ridge in the mandible. It
contains loose areolar connective tissue, fibres from the buccinator, superior constrictor and
the temporalis muscle. Posteriorly the retromolar pad is limited by the Pterygo-mandibular
raphe.
This pad resists resorption because of the action of the muscle fibres in it, and so is an
important landmark. It serves as a guide in the construction of the lower record block. Here
the occlusion rim is fabricated to be at the level of half the height of the pad. This pad must
always be covered by the lower denture to enhance the qualities of retention, support and
stability
The External Oblique Ridge - It is a ridge of dense bone. The external oblique line extends
from just above the mental foramen- going superiorly and in a distal direction becoming
continuous with the anterior border of the ramus. Most often is the anatomic guide for the lateral
termination of the buccal flange of mandibular denture.
The Buccal Shelf Area
ExtensionsBounded Inferiorly by the external oblique ridge.
Superiorly by the residual alveolar ridge.
Anteriorly by the buccal frenum.
Posteriorly by the retromolar pad.
Designated as the primary stress bearing area because
1. density of bone,
2. mucosal covering, and
3. relation to the vertical closure of the jaws ,
4.
are favourable to best resist forces transmitted through the denture base.
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The Mental Foramen
If bone resorption in the mandible becomes extreme the mental foramen may open near or
directly at the crest of the residual bony process. Pressure from the denture against the mental
nerve exiting the foramen will cause pain.
The Mylohyiod Line
It is a irregular rough bony crest extending from the third molar to the lower border of the
mandible in the area of the chin.
Mandibular lingual flange must extend inferior to the mylohyoid line.
If the crest becomes too prominent or sharp that it becomes a stress bearing surface or fulcrum
point surgical intervention is required.
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The Genial Tubercles
They are two small bony prominences on the inner surface of the mandible on each side of the
midline. The geniohyoid and genioglossus muscle is attached to these bony prominences. These
prominences are sometimes exaggerated and the cause problems in complete denture
construction
Mandibular Denture - Limiting Structures
–
Buccal and Labial Borders
–
Lingual border Anatomy
Buccal and Labial Borders
1. Labial Frenum
2. Labial Vestibule
3. Buccal Frenum
4. Buccal Vestibule
5. Massetric Notch Area
6. Retromolar Pad
Lingual border Anatomy
1. Lateral Throat Form
2. Retro-mylohyoid Region
3. Lingual crescent area
4. Lingual Frenum
Lateral Throat Form
The angle formed by the attachment of the tongue to the mucosa on the internal surface of
the mandible near the floor of the mouth.
Knowledge of the shape of this region helps in correct extension of the denture borders.
This in turn helps improve retention especially in otherwise unfavourable ridge types.
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7.
8.
Lingualpouch / Retro Mylohyoid Sulcus
The area posterior to the Palatoglossal arch is an undercut area and may be used by the distolingual flange to improve retention in the Lower denture. The denture a should whenever
possible engage this area to improve its retentive qualities.
Lingual
crescent area
Retro Mylohyoid Sulcus
Lingual crescent area
The anterior lingual area adjacent to the lingual frenum extending to the premolar region.
Lingual Frenum
It is a fold of mucous membrane that extends from the floor of the mouth to the under surface of
the tongue in the midline. As it moves during the function of the tongue, a corresponding
lingual frenal notch is needed in this region to avoid injury or entrapment of this tissue
Additional Reading Resources
- Complete Denture Textbooks by- Zarb and Bolender -12
Edition , Heartwell and Rahn-5th Edition, Bernard Levin – Complete Denture Impressions.
10
th
Edition , Sheldon Winkler-2nd