Anatomy for Complete and Partial Dentures

Anatomy for Complete and Partial Dentures

LipsLips

• Vermilion Border– Denture provides lip support

• Affects vermilion border width

• Vermilion Border– Denture provides lip support

• Affects vermilion border width

LipsLips

• Philtrum – Depression below nose

• Philtrum – Depression below nose

LipsLips

• Nasolabial Angle– Angle between columella of nose &

philtrum of lip

– Normally, approximately 90° as viewed in profile

• Nasolabial Angle– Angle between columella of nose &

philtrum of lip

– Normally, approximately 90° as viewed in profile

LipsLips

• Tissue of the Upper Lip– Loose tissue of the upper lip

can be gathered between your thumb and index finger

• Tissue of the Upper Lip– Loose tissue of the upper lip

can be gathered between your thumb and index finger

CheeksCheeks

• Masseter Muscle– Closing muscle bulges into distal corner of

buccal vestibule

– Not active during impression making

• Masseter Muscle– Closing muscle bulges into distal corner of

buccal vestibule

– Not active during impression making

Cross Sectional Shape of Masseter

ClosedOpen

Residual RidgesResidual Ridges

• If ridges are severely resorbed, inform patient– “U”-shape

– “V”-shape

• If ridges are severely resorbed, inform patient– “U”-shape

– “V”-shape

VestibulesVestibules

• If vestibules are shallow, inform the patient• If vestibules are shallow, inform the patient

MaxillaMaxilla

• Maxillary Tuberosities– Oversized

– Resorbed

– Undercut

• Maxillary Tuberosities– Oversized

– Resorbed

– Undercut

MaxillaMaxilla

• Maxillary Tuberosities– Oversized

– Resorbed

– Undercut

• Maxillary Tuberosities– Oversized

– Resorbed

– Undercut

MaxillaMaxilla

• Incisive Papilla– Landmark for setting of teeth

• Incisive Papilla– Landmark for setting of teeth

MaxillaMaxilla

• “Hamular” Notch– Posterior border denture• “Soft displaceable tissue”, for comfort and

retention

• “Hamular” Notch– Posterior border denture• “Soft displaceable tissue”, for comfort and

retention

MaxillaMaxilla• “Hamular” Notch

– Posterior border denture• Between the bony

tuberosity and hamulus

• “Hamular” Notch– Posterior border denture

• Between the bony tuberosity and hamulus

MaxillaMaxilla

• “Hamular” Notch– Posterior border denture

• Sometimes posterior to where the depression in the soft tissue appears

• Use the head of your mirror to palpate the notch & mark with an indelible marker

• “Hamular” Notch– Posterior border denture

• Sometimes posterior to where the depression in the soft tissue appears

• Use the head of your mirror to palpate the notch & mark with an indelible marker

MaxillaMaxilla• Soft Palate

– Vibrating Line• Critical posterior border dentures

• Junction of movable and immovable portions of the soft palate

• Soft Palate– Vibrating Line

• Critical posterior border dentures

• Junction of movable and immovable portions of the soft palate

MaxillaMaxilla

• Glandular Tissue– Soft displaceable

• Glandular Tissue– Soft displaceable

MaxillaMaxilla

• Soft Palate– Fovea Palatine

• Bilateral indentations near midline of the soft palate

• Close to the vibrating line

• Soft Palate– Fovea Palatine

• Bilateral indentations near midline of the soft palate

• Close to the vibrating line

MaxillaMaxilla

• Hard Palate– Median Palatine Raphe (midline palatine

suture)• A bony midline structure• May require relief when covered by a denture

• Hard Palate– Median Palatine Raphe (midline palatine

suture)• A bony midline structure• May require relief when covered by a denture

MaxillaMaxilla

• Torus Palatinus– May require removal

• Torus Palatinus– May require removal

MandibleMandible

• Pear Shaped Pad– Soft pad containing glandular tissue

– Inverted pear shape, posterior border

– Created from scarring after extractions

• Pear Shaped Pad– Soft pad containing glandular tissue

– Inverted pear shape, posterior border

– Created from scarring after extractions

MandibleMandible

• Buccal Shelf– Primary denture bearing area of mandibular

denture– Between height of bridge & external oblique ridge– Resorbs more slowly

• Buccal Shelf– Primary denture bearing area of mandibular

denture– Between height of bridge & external oblique ridge– Resorbs more slowly

MandibleMandible

• Anterior Border of the Ramus– Do not extend dentures to ramus

– Discomfort will result

• Anterior Border of the Ramus– Do not extend dentures to ramus

– Discomfort will result

MandibleMandible

• External Oblique Ridge– Do not extend dentures to this ridge

• External Oblique Ridge– Do not extend dentures to this ridge

MandibleMandible

• Mylohyoid Ridge– Origin of mylohyoid muscle which

influences length of lingual flange

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

• Mylohyoid Ridge– Origin of mylohyoid muscle which

influences length of lingual flange

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

MandibleMandible

• Lingual Tori– Raised bony structures – May require relief when covered by a denture– Thin mucosa can ulcerate easily

• Lingual Tori– Raised bony structures – May require relief when covered by a denture– Thin mucosa can ulcerate easily

MandibleMandible

• Genial Tubercles– Attachment for the genioglossus muscle

– Tubercles may be higher than the ridge with severe resorption

• Genial Tubercles– Attachment for the genioglossus muscle

– Tubercles may be higher than the ridge with severe resorption

Frena (singular = 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

• 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

Pterygo-Mandibular RaphePterygo-Mandibular Raphe

• Connects from the hamulus to the mylohyoid ridge

• When prominent, can cause pain, or loosening

• Requires relief “groove ” if prominent

• Connects from the hamulus to the mylohyoid ridge

• When prominent, can cause pain, or loosening

• Requires relief “groove ” if prominent

Retrozygomal Fossae (Space)Retrozygomal Fossae (Space)

• Palpate zygomatic process in buccal vestibule just buccal to first maxillary molar

• Vestibular space posterior to zygoma

• Palpate zygomatic process in buccal vestibule just buccal to first maxillary molar

• Vestibular space posterior to zygoma

Retrozygomal Fossae (Space)Retrozygomal Fossae (Space)

• Commonly incompletely captured in preliminary impressions

• Use syringe technique

• Commonly incompletely captured in preliminary impressions

• Use syringe technique

Coronoid ProcessCoronoid Process

• Place mirror head lateral to tuberosity

• Move mandible to opposite side

• Note binding or pain

• This gives some indication of the width of the space for flange

• Place mirror head lateral to tuberosity

• Move mandible to opposite side

• Note binding or pain

• This gives some indication of the width of the space for flange