Anatomy for Complete Denture

Terminology

• Prosthodontics: the branch of dentistry that

deals with the replacement missing dental

,oral and craniofacial structure.

• Prosthesis: an artificial replacement of an • Prosthesis: an artificial replacement of an

absent part of the human body.

• Dentulous: A condition in which complete set

of natural teeth are present in the mouth.

Edentulous :a condition in which the

mouth is without teeth it may be partially

edentulous or completely edentulous.

WASHINGTON’S DENTURE

OBJECTIVES OF COMPLETE DENTURE

OBJECTIVES OF COMPLETE

DENTURE

OBJECTIVES OF COMPLETE

DENTURE

Polished surface

Fitting surface

Buccal flange

Polished surface

Occlusal surface

Anatomy for Complete DenturesAnatomy for Complete DenturesAnatomy for Complete DenturesAnatomy for Complete Dentures

EXTRA ORAL LANDMARKSEXTRA ORAL LANDMARKS

Lips

• Vermilion Border

– Denture provides lip support

• Affects vermilion border width

Lips

• Philtrum

– Depression below nose

Lips

• Nasolabial Angle

– Angle between columella of nose & philtrum of lip

– Normally, approximately 90° as viewed in profile

• 4- NasoNaso--labial sulcus:labial sulcus:

– Def.: it is a depression that extends from the ala of the nose

in a downward and lateral direction to the corner of the

mouth.

– Prosthetic importance:

it becomes more prominent withit becomes more prominent with

aging and teeth loss so should be

restored by proper:-

– vertical dimension

- anterior teeth positioning

- labial flange

•• MentoMento--labial sulcuslabial sulcus:

– Def.: it is the sulcus between lower lip and chin.

– Prosthetic importance:

its curvature indicates the character of maxillo-mandibular its curvature indicates the character of maxillo-mandibular

relationship.

Class II angle Class I angle Class III angle

• Modiolus:

– Def.: this is located at the confluence of the

buccinator and other facial muscles near the angle

of the mouth.

– Prosthetic importance: – Prosthetic importance:

sunken cheeks appearance and

droped angle observed by loss

of maxillary teeth.

Intra-oral landmarks

SUPPORTING STRUCTURESUPPORTING STRUCTURE

Residual ridge:It is the portion of the alveolar process and its soft tissue coverage that

remains after extraction.

the highest continuous surface of the ridge is called

Crest of the ridgeCrest of the ridge

Residual ridge is considered one

of the primary stress bearing area.

Residual Ridges

– “U”-shape

– “V”-shape

– Flat

– Rounded – Rounded

Maxillary tuberosity

It is a prominent bulge located just behind and above the distal end of the

maxillary ridge

well formed tuberosities offer wide coverage so enhancing support and

retention of the denture.

However extremely large ones

needs surgical correction.

Maxilla

• Maxillary Tuberosities

– Oversized

– Resorbed

– Undercut

Maxilla

• Incisive Papilla

– Landmark for setting of teeth

Maxilla

• Hard Palate

– Median Palatine Raphe (midline palatine suture)

• A bony midline structure

• May require relief when covered by a denture

Maxilla

• Torus Palatinus

– May require removal

Maxilla

• “Hamular” Notch

– Posterior border denture

• Between the bony tuberosity and hamulus

• “Soft displaceable tissue”, for comfort and retention

Maxilla

• Soft Palate

– Fovea Palatine

• Bilateral indentations near midline of the soft palate

• Close to the vibrating line

Maxilla• Soft Palate

–Vibrating Line

• Critical posterior border dentures

• Junction of movable and immovable • Junction of movable and immovable portions of the soft palate

Mandible

• Ridge form

– U-shape best

Non-moveable best– Non-moveable best

– Advise patient if poor

– Affects:

• retention

• stability

Mandible

• Pear Shaped Pad(retromolar pad)

– Soft pad containing glandular tissue

– Pear shape, posterior border

– Created from scarring after extractions– Created from scarring after extractions

Mandible

• External Oblique Ridge

– Do not extend dentures to this ridge

Mandible

• Buccal Shelf

– Primary denture bearing area of mandibular denture

– Between height of bridge & external oblique ridge

– Resorbs more slowly

Mandible

• Lingual Tori

– Raised bony structures

– May require relief when covered by a denture– May require relief when covered by a denture

– Thin mucosa can ulcerate easily

Mandible

• Mylohyoid Ridge

– Origin of mylohyoid muscle which influences length

of lingual flange

– Can be prominent, and/or sharp, requiring relief

Mandible

• Genial Tubercles

– Attachment for the genioglossus muscle

– Tubercles may be higher than the ridge with severe

resorption

BORDER STRUCTURES THAT LIMITS

THE PREPHERY OF THE DENTURETHE PREPHERY OF THE DENTURE

Labial frenum

Frena (singular = frenum)

• Must be relieved to allow movement, without

impingement

• If prominent, adequate relief can weaken a denture

• If too much relief, retention is lost

• Check prominence intraorally• Check prominence intraorally

LingualLingual frenumfrenum

Buccal frenumBuccal frenum

Limiting structures of maxillary

denture

Labial frenum

Buccal frenum

Labial vestibule

Buccal frenum

Hamular notch

Vibrating line of soft palate

Buccal vestibule

Limiting structures of mandibular

dentureLabial frenum

Buccal frenum

Lingual frenum Buccal

Retromolar bad

Lingual pouch

vestibule

• Retention :resistance to the dislodging forces along

the path of placement.

• Stability :to be firm, steady or constant to resist

displacement by functional horizontal or rotational

stresses.stresses.

• Support :the foundation area on which a dental

prosthesis rest. It is the resistance to the force

toward the tissue.

Take time TO LIVE… Take time TO LIVE… Because time passes… QUICKLYBecause time passes… QUICKLY

And NEVER returns!And NEVER returns!