INDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com
www.indiandentalacademy.com
Anatomy & Physiology
of the
Denture Bearing areas
www.indiandentalacademy.com
Contents
Introduction
Anatomy of the denture supporting
structures of Maxilla
Anatomy of Peripheral or limiting
structures...
MUCOUS MEMBRANE
It is composed of mucosa and sub mucosa.
The mucosa is formed by stratified squamous
epithelium, which oft...
The mucosa varies in its thickness and density ,
thinnest covering the midpalatine raphe next
thinnest being the mucosa co...
Residual ridge
The bone that is left behind after all the teeth are
removed and after a disease or surgery affected.
First...
The ridge varies greatly in size and shape and its
ultimate form is dependent on the following
factors:-
Original size, sh...
Musculature.
Amount of the bone loss due to the
disease
before extraction
Duration of edentulousness and the rate
of resor...
Hard palate
The ultimate support for the maxillary
denture is the hard palate
The two palatine process of the maxilla
fuse...
In the region of the midpalatine suture the sub
mucosa is very thin and it has to be relieved .
Quite often in the mid pal...
Rugae
In the area of the rugae the palate is set at
an angle to the ridge and rather thinly
covered by the soft tissue.
Th...
They also enable the tongue to form a
perfect seal when it is pressed against the
palate in making the linguo palatal
cons...
Maxillary tuberosity
It is a bony prominence situated at the posterior
aspect of alveolar ridge.
A broad well rounded tube...
Tuberosities sometimes exhibit buccal undercuts ,
if it is unilateral it can be utilized for the retention.
If excess hype...
Incisivepapilla
It is a thick fibrous connective tissue covering the
incisive foramen.
It is located on the line immediate...
The horizontal distance between the
perpendicular line from incisive papilla to labial
surfaces of incisors should be abou...
Zygomatic process
It is also called as malar process.
It is located opposite the first molar region.
It is prominent in th...
Pterygomandibular raphe
It originates from the hamular process and
in close proximity to the distal edge of the
upper dent...
Sharp spiny process
Frequently there are sharp spiny process
on the maxillary and palatine bones that
are deeply covered w...
Labial Frenum
It is a fan shaped fibrous pack covered by mucus
membrane that extends from the inner aspect of upper
lip an...
It is relieved by making up and downward
movements of upper lip.It is seen as a V shaped
notch in the impression
www.india...
Labial Vestibule
Labial Vestibule is divided in to left and right by
the labial frenum
The mucous membrane lining the labi...
Over extension of labial flange of the denture
causes ulceration or instability of the denture
The thickness of the flange...
Buccal frenum
It’s a fold of mucous membrane overlying the muscles
near the premolar region
It may be single or multiple. ...
Buccal Vestibule
It lies opposite the tuberosity and extends from
the buccal frenum to the Hamular notch
The size of the v...
Width of the buccal flange is determined by
making side ward movement of the mandible and
during this movement the coronoi...
Pterygomaxillary notch
It’s a bony depression between tuberosity
and hamulus of the medial pterygoid plate
This forms the ...
Fovea palatine
These are the depressions or indentations
situated on the soft palate on the either
side of the midline
It ...
Posterior palatal seal
It is defined as the soft tissues along the
junction of the hard and soft palates on
which pressure...
The proper placement of it will reduces the
patient awareness of this area with subsequent
reduction in the Gag reflex.
It...
The correct placement of the seal will not
impinge up on the non displaceable tissues of
hard palate and it will not limit...
Anterior vibrating line
It is an imaginary line located at the junction of
the attached tissues overlying the hard palate
...
Due to the projection of the posterior nasal
spine, this line is not a straight line between both
Hamular processes
It is ...
Posterior vibrating line
It is an imaginary line at the junction of the
aponeurosis of the Tensorveli palatina muscle
and ...
It is visualised by instructing the patient to say
“AH” in short bursts in a normal un exaggerated
fashion.
It marks the m...
The rational for the placement of seal in the
impression tray is as follows
1).To establish positive contact posteriorly t...
Technique to determine posterior palatel seal
are
1).Conventional approach
2).Fluid wax technique
3).Arbitaryscraping of t...
Crest of the residual ridge
The ridge is covered by fibrous connective
tissue.
The under lying bone is cancellous bone
whi...
The buccal shelf or buccal flange
The area between the mandibular buccal
frenum and the anterior edge of the
masseter musc...
The mucous membrane covering this area is
loosely attached and less keratinised and has
thicker submucosal layer.Hence it ...
Mylohyoid ridge
Soft tissue usually hides the sharpness of the
mylohyoid ridge.
The shape and inclination of the ridge var...
The mucous membrane over a sharp or
irregular mylohyoid ridge will be easily
traumatized by the denture base.
The area und...
Mental foramen
Severe resorption of bone results in
mental foramen lying close to or at the
crest of the ridge results in ...
Genial Tubercles
They usually lie well away from the crest of
the ridge
However with the resorption the genial
tubercles b...
Torus mandibularis
This is a bony prominence usually found
bilaterally and lingually near the first and
second premolars m...
It is covered by extremely thin layer of mucous
membrane which often needs to be corrected
surgically as it cannot be reli...
External oblique line
It is a ridge of the dense bone extending
from just above the mental foramen in a
superior and dista...
Buccal & Labial borders
The labial frenum contains a band of
fibrous connective tissue that helps attach
the orbicularis o...
Buccal Frenum
It connects as a continuous band through the
modiolus at the corner of the mouth to the
buccal frenum in the...
Labial Vestibule
It runs from the buccal to the labial frenum
The mentalis muscle is particularly active
muscle in this re...
Buccal vestibule
It extends posterior from the buccal frenum to the outside
back corner of the retro molar pad
The extent ...
The flange which starts immediately posterior to the
frenum swings wide in o the cheek and it is nearly right
angle o the ...
Retro Molar pad
It is triangular soft pad of tissues at the
digital end of he lower ridge
Its mucosa is composed of a thin...
The action of these muscles limits the extent of
the denture and prevents placement of extra
pressure on the distal part o...
Mylohyoid muscle
The floor of the month is formed by this
muscle which arises from the whole length
of the Mylohyoid ridge...
The muscle lies deep to the sub lingual
gland and other structures in the anterior
region and so does not affect the dentu...
An extension of the lingual flange well beyond
the palpable position of the ridge,but not in to
the undercut has other adv...
Retromylohyoid fossa
It is the area posterior to the mylohyoid
muscle
As the lingual flange moves in to this
fossa.It ceas...
It is bounded by the retromylohyoid
curtain
The postero lateral portion of the curtain
overlies the superior constrictor
m...
The denture border should extend posteriorly to
contact the curtain when the tip of the tongue is
placed against the front...
Sublingual gland region
In the premolar region the sub lingual
gland rest above the mylohyoid
muscle
When the floor of the...
This can be avoided by shaping this part of the
flange of the tray to slope inward, toward the
tongue and making the final...
Alveololingual sulcus
It is the space between the ridge and tongue
extending from the lingual frenum to the retro
mylohyoi...
Premylohyoid fossa is palpated and a
corresponding eminence seen on the
impressions
The lingual border in this region shou...
Middle region:
This region extends from pre mylohyoid
fossa to the distal end of the mylohyoid
ridge,curving medially from...
Conclusion
The denture bearing areas not only support
the dentures but have a direct bearing on
the impression making proc...
Bibliography
Boucher’s Prosthodontic Treatment for
Edentulous patients – 10th
Edition
Boucher’s Prosthodontic Treatment fo...
Thank you
For more details please visit
www.indiandentalacademy.com
www.indiandentalacademy.com
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Anatomy and physiology/ cosmetic dentistry training

  1. 1. INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  2. 2. Anatomy & Physiology of the Denture Bearing areas www.indiandentalacademy.com
  3. 3. Contents Introduction Anatomy of the denture supporting structures of Maxilla Anatomy of Peripheral or limiting structures of Maxilla Anatomy of the denture supporting structures of Mandible Anatomy of Peripheral or limiting structures of Mandible Conclusion Bibliography www.indiandentalacademy.com
  4. 4. MUCOUS MEMBRANE It is composed of mucosa and sub mucosa. The mucosa is formed by stratified squamous epithelium, which often is keratinised and a subjacent narrow layer of connective tissue known as the laminapropria. In the edentulous person the mucosa covering the ridge and the palate is called the masticatory mucosa www.indiandentalacademy.com
  5. 5. The mucosa varies in its thickness and density , thinnest covering the midpalatine raphe next thinnest being the mucosa covering the ridges and thickest covering the blood vessels and nerves of the lateral aspects of the palate. www.indiandentalacademy.com
  6. 6. Residual ridge The bone that is left behind after all the teeth are removed and after a disease or surgery affected. First it was considered to be the primary stress bearing area but it is looked upon the secondary stress bearing area because of the fact that bone is subjected to continuous resorption though it decreases as the span of the edentulousness increases. www.indiandentalacademy.com
  7. 7. The ridge varies greatly in size and shape and its ultimate form is dependent on the following factors:- Original size, shape and calcification of the bone . Size of the natural teeth General health of the patient. Forces exerted by the surrounding www.indiandentalacademy.com
  8. 8. Musculature. Amount of the bone loss due to the disease before extraction Duration of edentulousness and the rate of resorption Effect of previous prosthesis www.indiandentalacademy.com
  9. 9. Hard palate The ultimate support for the maxillary denture is the hard palate The two palatine process of the maxilla fuse together to form the hard palate at the mid palatine suture. It is covered by the mucosa of varying thickness. www.indiandentalacademy.com
  10. 10. In the region of the midpalatine suture the sub mucosa is very thin and it has to be relieved . Quite often in the mid palatine suture, a hyperplastic growth of bone is seen. This intervenes with the stability of the denture, this called as torus palatinus. Steps should be taken to obtain considerable relief by using the special impression techniques, mechanical relief or by the last resort, by its surgical excision. www.indiandentalacademy.com
  11. 11. Rugae In the area of the rugae the palate is set at an angle to the ridge and rather thinly covered by the soft tissue. This is considered to be the secondary stress bearing area Rugae are said to be associated with the sense of taste and the function of speech They assist the tongue to absorb via its papillae. www.indiandentalacademy.com
  12. 12. They also enable the tongue to form a perfect seal when it is pressed against the palate in making the linguo palatal constant stops of speech. Rugae should not be displaced,otherwise the rebounding may dislodge the denture. They provide anteroposterior resistance to movement of the denture and increased surface area helps in retention. www.indiandentalacademy.com
  13. 13. Maxillary tuberosity It is a bony prominence situated at the posterior aspect of alveolar ridge. A broad well rounded tuberosity of sufficient height is favorable. Large maxillary tuberosities bounded by deep sulci offer very satisfactory resistance to the lateral movement of the denture. www.indiandentalacademy.com
  14. 14. Tuberosities sometimes exhibit buccal undercuts , if it is unilateral it can be utilized for the retention. If excess hyperplastic tissue is present it should be surgically corrected. www.indiandentalacademy.com
  15. 15. Incisivepapilla It is a thick fibrous connective tissue covering the incisive foramen. It is located on the line immediately behind and between the central incissors. Relief for the papilla should be provided to prevent any possible interferences with the blood and nerve supply. Clinical significance:- it helps to determine the midline. it determines the position of the upper anteriors. it helps to assess the amount of resorption because it does not change the position. www.indiandentalacademy.com
  16. 16. The horizontal distance between the perpendicular line from incisive papilla to labial surfaces of incisors should be about 8-10mm. It helps in selecting the size of the upper anteriors i.e the horizontal line drawn cutting the papilla and extending over the land surface should coincide with the position of the upper canine tooth. It helps in determing the vertical dimension of occlusion i.e distance between the incisal edge and the papilla should be 4 mm. www.indiandentalacademy.com
  17. 17. Zygomatic process It is also called as malar process. It is located opposite the first molar region. It is prominent in the long span edentulous people. In some cases it requires relief over this area to aid in retention and prevent soreness of the underlying tissues. www.indiandentalacademy.com
  18. 18. Pterygomandibular raphe It originates from the hamular process and in close proximity to the distal edge of the upper denture. If this edge is over extended it will impinge on the fold of the soft tissue which is elevated when the mouth is open and the raphe becomes tensed. This causes inflammation and often reported as soreness of the throat or the denture flips downwards each time when patient opens the mouth. www.indiandentalacademy.com
  19. 19. Sharp spiny process Frequently there are sharp spiny process on the maxillary and palatine bones that are deeply covered with the soft tissue. In patients with the considerable resorption of the ridge these spines irritates the soft tissues left between them and the denture base. www.indiandentalacademy.com
  20. 20. Labial Frenum It is a fan shaped fibrous pack covered by mucus membrane that extends from the inner aspect of upper lip and attached to the labial aspect of residual ridge. It is usually single and does not contain muscle fibres It has to be relieved while making impression in order to prevent dislodgement of the denture and to prevent Ulceration and the upper lip will be pushed away from the functional depth and there will be more visibility of the teeth www.indiandentalacademy.com
  21. 21. It is relieved by making up and downward movements of upper lip.It is seen as a V shaped notch in the impression www.indiandentalacademy.com
  22. 22. Labial Vestibule Labial Vestibule is divided in to left and right by the labial frenum The mucous membrane lining the labial vestibule has a relatively thin mucosa with a epithelium that is non keratinised The depth of the labial sulcus depends on -height of the alveolar ridge -Mobility and tension of the surrounding muscles The labial sulcus is relieved by functional moulding of the upper lip www.indiandentalacademy.com
  23. 23. Over extension of labial flange of the denture causes ulceration or instability of the denture The thickness of the flange provides stability and peripheral seal www.indiandentalacademy.com
  24. 24. Buccal frenum It’s a fold of mucous membrane overlying the muscles near the premolar region It may be single or multiple. It divides the labial and buccal vestibules. It requires more clearance for its action than the labial frenum It moves mesially,buccaly and vertically Orbicularis oris- Mesial movement Buccinator-Buccal movement Levator angulioris and Canninus –Vertical movement www.indiandentalacademy.com
  25. 25. Buccal Vestibule It lies opposite the tuberosity and extends from the buccal frenum to the Hamular notch The size of the vestibule varies with the contraction of the Buccinator muscle,position of the mandible,amount of the bone loss from the maxilla Compare to the labial flange ,buccal flange has less interferences and so provides maximum retention www.indiandentalacademy.com
  26. 26. Width of the buccal flange is determined by making side ward movement of the mandible and during this movement the coronoid process will be closed to the tuberosity Excessive thickness of buccal flange will displace the denture when the patient opens the mouth wide www.indiandentalacademy.com
  27. 27. Pterygomaxillary notch It’s a bony depression between tuberosity and hamulus of the medial pterygoid plate This forms the distal limit of the upper denture It is covered by the mucosa of sufficient thickness and can be compressed to achieve peripheral seal Over extension will lead to the pain and dislodgment of the denture www.indiandentalacademy.com
  28. 28. Fovea palatine These are the depressions or indentations situated on the soft palate on the either side of the midline It helps to determine the midline and positioning of the posterior border These are the ductal openings in to which ducts of other palatal mucous glands drain www.indiandentalacademy.com
  29. 29. Posterior palatal seal It is defined as the soft tissues along the junction of the hard and soft palates on which pressure with in the physiologic limits of the tissues can be applied by a denture to aid in the retention of the denture. Its significance is -To maintain contact with the anterior portion of the soft palate during the functional movements,therefore the primary purpose of it is retention of the denture. www.indiandentalacademy.com
  30. 30. The proper placement of it will reduces the patient awareness of this area with subsequent reduction in the Gag reflex. It reduces the food accumulation beneath the posterior aspect of the denture It reduces the patient discomfort when contact occurs between the dorsum of the tongue and the posterior end of the denture base As it lies in close approximation to the soft palatal tissue, it compensates for the volumetric shrinkage that occurs during polymerization of Methyl Methacrylate resin www.indiandentalacademy.com
  31. 31. The correct placement of the seal will not impinge up on the non displaceable tissues of hard palate and it will not limit the muscular movements of the soft palate It will create a partial vacuum beneath the maxillary denture. It is activated only when horizontal or tipping forces are directed against denture base www.indiandentalacademy.com
  32. 32. Anterior vibrating line It is an imaginary line located at the junction of the attached tissues overlying the hard palate and the movable tissues of immediately adjacent soft palate One way to locate the line is to ask the patient perform the Valsalva maneuver which requires that both nostrils be held firmly while the patient blows gently through the nose It can also be approximated by visualisig the area while instructing the patient to say ”AH” with short vigorous bursts www.indiandentalacademy.com
  33. 33. Due to the projection of the posterior nasal spine, this line is not a straight line between both Hamular processes It is always on soft palatal tissues www.indiandentalacademy.com
  34. 34. Posterior vibrating line It is an imaginary line at the junction of the aponeurosis of the Tensorveli palatina muscle and the muscular portion of the soft palate. It represents the demarcation between that part of the soft palate that has limited or shallow movement during function and the remainder of the soft palate that is markedly displaced during functional movements www.indiandentalacademy.com
  35. 35. It is visualised by instructing the patient to say “AH” in short bursts in a normal un exaggerated fashion. It marks the most distal extension of the denture base. www.indiandentalacademy.com
  36. 36. The rational for the placement of seal in the impression tray is as follows 1).To establish positive contact posteriorly to prevent the final impression material from sliding down the pharynx 2).To serve as a guide for positioning the impression tray 3).To create slight displacement of the soft palate 4).To determine if adequate retention and seal of the potential denture border is present www.indiandentalacademy.com
  37. 37. Technique to determine posterior palatel seal are 1).Conventional approach 2).Fluid wax technique 3).Arbitaryscraping of the master cast www.indiandentalacademy.com
  38. 38. Crest of the residual ridge The ridge is covered by fibrous connective tissue. The under lying bone is cancellous bone which cannot take up the masticatory loads. the fibrous connective tissue closely attached to the bone is favourable for resisting applied forces, such as those from a denture. The mean denture bearing area is 13.95sq.cm www.indiandentalacademy.com
  39. 39. The buccal shelf or buccal flange The area between the mandibular buccal frenum and the anterior edge of the masseter muscle is known as buccal shelf. It is bound medially--crest of the residual ridge. Laterally--external oblique ridge. Distally --retromolar pad. The total width of the bony foundation in this region becomes greater as alveolar resorption continues. www.indiandentalacademy.com
  40. 40. The mucous membrane covering this area is loosely attached and less keratinised and has thicker submucosal layer.Hence it may not be histologically suitable to provide primary support for the denture. How ever the bone of the buccal shelf and the fact that it lies at right angles to the vertical occlusal forces makes it suitable primary stress bearing area for the denture. The inferior part of the buccinator muscle is attached to the buccal shelf and its fibers are found in the submucosa immediately overlying the bone www.indiandentalacademy.com
  41. 41. Mylohyoid ridge Soft tissue usually hides the sharpness of the mylohyoid ridge. The shape and inclination of the ridge vary greatly among the edentulous people. Anteriorly the mylohyoid muscle is attached and lies close to the inferior border of the mandible. posteriorly following resorption, it often lies flush with the superior surface of the ridge. www.indiandentalacademy.com
  42. 42. The mucous membrane over a sharp or irregular mylohyoid ridge will be easily traumatized by the denture base. The area under the ridge is an undercut. www.indiandentalacademy.com
  43. 43. Mental foramen Severe resorption of bone results in mental foramen lying close to or at the crest of the ridge results in compression of the mental nerves and blood vessels,if relief is not provided in the denture base. Pressure on the mental nerve can cause numbness of the lower lip. www.indiandentalacademy.com
  44. 44. Genial Tubercles They usually lie well away from the crest of the ridge However with the resorption the genial tubercles become increasingly prominent www.indiandentalacademy.com
  45. 45. Torus mandibularis This is a bony prominence usually found bilaterally and lingually near the first and second premolars mid way between the soft tissues of the floor of the mouth and the crest of the alveolar ridge In the edentulous mouth where considerable resorption takes place, the superior border of the torus may be flush with crest of the ridge www.indiandentalacademy.com
  46. 46. It is covered by extremely thin layer of mucous membrane which often needs to be corrected surgically as it cannot be relieved with in the denture with out breaking the border seal www.indiandentalacademy.com
  47. 47. External oblique line It is a ridge of the dense bone extending from just above the mental foramen in a superior and distal direction to become continuous with the anterior border of the ramus It is an anatomical guide for the lateral termination of the buccal flange of the denture www.indiandentalacademy.com
  48. 48. Buccal & Labial borders The labial frenum contains a band of fibrous connective tissue that helps attach the orbicularis oris Therefore the frenum is quite sensitive and active and must be carefully fitted to maintain a seal without causing soreness www.indiandentalacademy.com
  49. 49. Buccal Frenum It connects as a continuous band through the modiolus at the corner of the mouth to the buccal frenum in the maxilla This fibrous and muscular tissues pull actively across the denture borders, polished surfaces and teeth Therefore denture should extend less in this region and the impression must be functionally trimmed to have the maximum seal and yet not displace the denture when the lip is moved www.indiandentalacademy.com
  50. 50. Labial Vestibule It runs from the buccal to the labial frenum The mentalis muscle is particularly active muscle in this region It contains a band of fibrous connective tissue that helps attach the orbicularis oris muscle www.indiandentalacademy.com
  51. 51. Buccal vestibule It extends posterior from the buccal frenum to the outside back corner of the retro molar pad The extent of the vestibule is influenced by buccinator muscle anteriorly to the pterygomandibular raphe posteriorly its lower fibres attached to the buccal shelf and external oblique ridge www.indiandentalacademy.com
  52. 52. The flange which starts immediately posterior to the frenum swings wide in o the cheek and it is nearly right angle o the biting force. The impression is always widest in this region The disto buccal border at the end of the vestibule must converge rapidly to avoid displacement by the contracting masseter muscle whose anterior fibers run outside and behind the buccinator muscle in this region www.indiandentalacademy.com
  53. 53. Retro Molar pad It is triangular soft pad of tissues at the digital end of he lower ridge Its mucosa is composed of a thin non keratinized epithelium and in addition its sub mucosa contains glandular tissue and fibers of the buccinator and superior constrictor muscles,the pterygomandibular raphe and the terminal part of the tendon of the temporalis muscle www.indiandentalacademy.com
  54. 54. The action of these muscles limits the extent of the denture and prevents placement of extra pressure on the distal part of the retro molar pad during the impression procedures www.indiandentalacademy.com
  55. 55. Mylohyoid muscle The floor of the month is formed by this muscle which arises from the whole length of the Mylohyoid ridge This ridge is sharp and distinct in the molar region and becomes almost indiscernible anteriorly Medially the fibres join those from the mylohoid muscle of the opposite side and posteriorly they continue to the hyoid base www.indiandentalacademy.com
  56. 56. The muscle lies deep to the sub lingual gland and other structures in the anterior region and so does not affect the denture border except indirectly The posterior part of h muscle in the molar region affects the lingual impression border in swallowing and in moving the tongue Extension of the lingual flange under this ridge cannot be tolerated in function because it will interfere with the action of he mylohyoid muscle when it contract will displace the denture causing soreness www.indiandentalacademy.com
  57. 57. An extension of the lingual flange well beyond the palpable position of the ridge,but not in to the undercut has other advantages. The lack of the direct pressure on the sharp edge of the ridge will eliminate the possible source of discomfort. www.indiandentalacademy.com
  58. 58. Retromylohyoid fossa It is the area posterior to the mylohyoid muscle As the lingual flange moves in to this fossa.It ceases to be influenced by the action of the mylohyoid muscle and so can move back towards the body of the mandible producing the typical “S” curve of the lingual flange www.indiandentalacademy.com
  59. 59. It is bounded by the retromylohyoid curtain The postero lateral portion of the curtain overlies the superior constrictor muscle,and postero medial portion covers the palatoglossal muscle plus the lateral surface of the tongue The inferior wall overlies the sub mandibular gland,which fills the gap between the superior constrictor muscle and the most distal attachment of the mylohyoid muscle. www.indiandentalacademy.com
  60. 60. The denture border should extend posteriorly to contact the curtain when the tip of the tongue is placed against the front part of the upper ridge. Protrusion of the tongue causes the curtain to move forward. www.indiandentalacademy.com
  61. 61. Sublingual gland region In the premolar region the sub lingual gland rest above the mylohyoid muscle When the floor of the mouth is raised the gland comes quite close to the crest of the ridge and reduces the vertical space available for the extension of the flange in the anterior part of the mouth www.indiandentalacademy.com
  62. 62. This can be avoided by shaping this part of the flange of the tray to slope inward, toward the tongue and making the final impression with low viscosity impression material www.indiandentalacademy.com
  63. 63. Alveololingual sulcus It is the space between the ridge and tongue extending from the lingual frenum to the retro mylohyoid curtain The anterior region: This extends from the lingual frenum back to where the mylohyoid ridge curves down below the level of the sulcus www.indiandentalacademy.com
  64. 64. Premylohyoid fossa is palpated and a corresponding eminence seen on the impressions The lingual border in this region should extend down to make contact with the mucus membrane, floor of the mouth when the tip of the tongue touches the upper incisors The flange will be shorter than the posterior flange www.indiandentalacademy.com
  65. 65. Middle region: This region extends from pre mylohyoid fossa to the distal end of the mylohyoid ridge,curving medially from the body of the mandible Posterior region: Flange passes in to the retrohyoid fossa and so mylohyoid muscle does not influence the denture border in this region www.indiandentalacademy.com
  66. 66. Conclusion The denture bearing areas not only support the dentures but have a direct bearing on the impression making procedures, the position of teeth and the contours of the finished denture base. Thus thorough knowledge of the anatomy and physiology of the supporting structures is essential for the success of the prosthesis www.indiandentalacademy.com
  67. 67. Bibliography Boucher’s Prosthodontic Treatment for Edentulous patients – 10th Edition Boucher’s Prosthodontic Treatment for Edentulous patients – 11th Edition Textbook of Complete dentures – Charles M.Heartwell Essentials of Complete denture prosthodontics – Sheldon Winkler www.indiandentalacademy.com
  68. 68. Thank you For more details please visit www.indiandentalacademy.com www.indiandentalacademy.com

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