NEET MDS Synopsis
Complete Denture Occlusion
ProsthodonticsComplete Denture Occlusion
Complete denture occlusion is a critical aspect of prosthodontics, as it
affects the function, stability, and comfort of the dentures. There are three
primary types of occlusion used in complete dentures: Balanced Occlusion,
Monoplane Occlusion, and Lingualized Occlusion. Each type has its own
characteristics and applications.
Types of Complete Denture Occlusion
1. Balanced Occlusion
Definition: Balanced occlusion is characterized by
simultaneous contact of all opposing teeth in centric occlusion, providing
stability and even distribution of occlusal forces.
Key Features:
Three-Point Contact: While a three-point contact
(one anterior and two posterior) is a starting point, it is not
sufficient for true balanced occlusion. Instead, there should be
simultaneous contact of all teeth.
Minimal Occlusal Balance: For minimal occlusal
balance, there should be at least three points of contact on the
occlusal plane. The more points of contact, the better the balance.
Absence in Natural Dentition: Balanced occlusion is
not typically found in natural dentition; it is a concept specifically
applied to complete dentures to enhance stability during function.
Importance: This type of occlusion is particularly
important for patients with complete dentures, as it helps to minimize
tipping and movement of the dentures during chewing and speaking.
2. Monoplane Occlusion
Definition: Monoplane occlusion involves a flat
occlusal plane where the occlusal surfaces of the teeth are arranged in a
single plane.
Key Features:
Flat Occlusal Plane: The occlusal surfaces are
designed to be flat, which simplifies the occlusion and reduces the
complexity of the denture design.
Limited Interference: This type of occlusion
minimizes interferences during lateral and protrusive movements, making
it easier for patients to adapt to their dentures.
Applications: Monoplane occlusion is often used in
cases where the residual ridge is severely resorbed or in patients with
limited jaw movements.
3. Lingualized Occlusion
Definition: Lingualized occlusion is characterized by
the positioning of the maxillary posterior teeth in a way that they occlude
with the mandibular posterior teeth, with the buccal cusps of the mandibular
teeth being positioned more towards the buccal side.
Key Features:
Maxillary Teeth Positioning: The maxillary
posterior teeth are positioned more towards the center of the arch,
while the mandibular posterior teeth are positioned buccally.
Functional Balance: This arrangement allows for
better functional balance and stability during chewing, as the maxillary
teeth provide support to the mandibular teeth.
Advantages: Lingualized occlusion can enhance the
esthetics and function of complete dentures, particularly in patients with a
well-defined ridge.
Vitiligo
General Pathology
Vitiligo is an autoimmune destruction of melanocytes resulting in areas of depigmentation.
- commonly associated with other autoimmune diseases such as pernicious anemia, Addison's disease, and thyroid disease.
- common in the Black population
Veins of the Face
AnatomyVeins of the Face
The Supratrochlear Vein
This vessel begins on the forehead from a network of veins connected to the frontal tributaries of the superficial temporal vein.
It descends near the medial plane with its fellow on the other side.
These veins diverge near the orbits, each joining a supraorbital vein to form the facial vein near the medial canthus (angle of the eye).
The Supraorbital Vein
This vessel begins near the zygomatic process of the temporal bone.
It joins the tributaries of the superficial and middle temporal veins.
It passes medially and joins the supratrochlear vein to form the facial vein near the medial canthus.
The Facial Vein
This vein provides the major venous drainage of the face.
It begins at the medial canthus of the eye by the union of the supraorbital and supratrochlear veins.
It runs inferoposteriorly through the face, posterior to the facial artery, but takes a more superficial and straighter course than the artery.
Inferior to the margin of the mandible, the facial vein is joined by the anterior branch of the retromandibular vein.
The facial veins ends by draining into the internal jugular vein.
The Superficial Temporal Vein
This vein drains the forehead and scalp and receives tributaries from the veins of the temple and face.
In the region of the temporomandibular joint, this vein enters the parotid gland.
The Retromandibular Vein
The union of the superficial temporal and maxillary veins forms this vessel, posterior to the neck of the mandible.
It descends within the parotid gland, superficial to the external carotid artery but deep to the facial nerve.
It divides into an anterior branch that unites with the facial vein, and a posterior branch that joins the posterior auricular vein to form the external jugular vein.
Classification of Periodontal Pockets
PeriodontologyClassification of Periodontal Pockets
Periodontal pockets are an important aspect of periodontal disease,
reflecting the health of the supporting structures of the teeth. Understanding
the classification of these pockets is essential for diagnosis, treatment
planning, and management of periodontal conditions.
Classification of Pockets
Gingival Pocket:
Also Known As: Pseudo-pocket.
Formation:
Formed by gingival enlargement without destruction of the
underlying periodontal tissues.
The sulcus is deepened due to the increased bulk of the gingiva.
Characteristics:
There is no destruction of the supporting periodontal tissues.
Typically associated with conditions such as gingival
hyperplasia or inflammation.
Periodontal Pocket:
Definition: A pocket that results in the
destruction of the supporting periodontal tissues, leading to the
loosening and potential exfoliation of teeth.
Classification Based on Location:
Suprabony Pocket:
The base of the pocket is coronal to the alveolar bone.
The pattern of bone destruction is horizontal.
The transseptal fibers are arranged horizontally in the
space between the base of the pocket and the alveolar bone.
Infrabony Pocket:
The base of the pocket is apical to the alveolar bone,
meaning the pocket wall lies between the bone and the tooth.
The pattern of bone destruction is vertical.
The transseptal fibers are oblique rather than horizontal.
Classification of Periodontal Pockets
Suprabony Pocket (Supracrestal or Supraalveolar):
Location: Base of the pocket is coronal to the
alveolar bone.
Bone Destruction: Horizontal pattern of bone loss.
Transseptal Fibers: Arranged horizontally.
Infrabony Pocket (Intrabony, Subcrestal, or
Intraalveolar):
Location: Base of the pocket is apical to the
alveolar bone.
Bone Destruction: Vertical pattern of bone loss.
Transseptal Fibers: Arranged obliquely.
Classification of Pockets According to Involved Tooth Surfaces
Simple Pocket:
Definition: Involves only one tooth surface.
Example: A pocket that is present only on the
buccal surface of a tooth.
Compound Pocket:
Definition: A pocket present on two or more
surfaces of a tooth.
Example: A pocket that involves both the buccal and
lingual surfaces.
Spiral Pocket:
Definition: Originates on one tooth surface and
twists around the tooth to involve one or more additional surfaces.
Example: A pocket that starts on the mesial surface
and wraps around to the distal surface.
PROSTHODONTICS QUESTIONS NEET MDS
NEET MDS
1. Following extraction of the molar teeth
A. The ridge height is lost more from the maxilla than from the mandible
B. The maxillary ridge will get more bone lost from the palatal aspect than the
buccal
C. The mandibular arch is relatively narrower than the maxillary arch
D. Compared with the pre-resorption state, the mandibular ridge will lose more
bone from the
lingual aspect than the buccal one
Ans D
2. Which of the following is a major disadvantage to immediate complete
denture therapy
A. Trauma to extraction site
B. Increased the potential of infection
C. Impossibility for anterior try in
D. Excessive resorption of residual ridge
Ans C
3. When repairing a fracture of lower complete denture. Which statement is
correct:
A. Self curing will distort the denture
B. Cold curing will not be strong enough because of small area of attachment
C. There is a possibility of occlusal disharmony
D. none
Ans C
4. The setting expansion of casting investment is approximately
A. 0 to 0.1%
B. 0.1 to 0.5%
C. 0.5 to 1%
D. 1.1 to 1.6%
Ans C
5. The un-polymerized monomer in Self-cured resin is approximately:
A. 0.5%
B. 2.5%
C. 5%
D. 10%
Ans A
6. A volume shrinkage of methyl meta cyrelate monomer when is polymerized:
A. 12%
B. 15%
C. 18%
D. 21%
Ans D
7. All of the following landmarks are included while making a post dam for
maxillary arch except
A) Pterygomaxillary notch
B) Hamular process
C) Fovea palatina
D) Vibrating line
Ans: B
8. The thickness of the spacer used in special tray is
A) 2.5mm
B) 2.0mm
C) 1.5mm
D) 1.0mm
Ans. B,
Wax spacer is used to provide the space in the tray for the final impression
material and allows the tray to be properly positioned in the mouth during
border molding procedures
Base plate wax covers the basal seat area except for labial and buccal
reflections and the posterior palatal seal area
OCCLUSION AND DENTAL DEVELOPMENT-Stages-Mixed Dentition Period
Dental Anatomy
Mixed Dentition Period.
-Begins with the eruption of the first permanent molars distal to the second deciduous molars. These are the first teeth to emerge and they initially articulate in an 'end-on' (one on top of the other) relationship.
-On occasion, the permanent incisors spread out due to spacing. In the older literature, is called by the 'ugly duckling stage.' With the eruption of the permanent canines, the spaces often will close.
-Between ages 6 and 7 years of age there are:
20 deciduous teeth
4 first permanent molars
28 permanent tooth buds in various states of development
The Superior Roof of the Orbit
AnatomyThe Superior Roof of the Orbit
The superior wall or roof of the orbit is formed almost completely by the orbital plate of the frontal bone.
Posteriorly, the superior wall is formed by the lesser wing of the sphenoid bone.
The roof of the orbit is thin, translucent, and gently arched. This plate of bone separates the orbital cavity and the anterior cranial fossa.
The optic canal is located in the posterior part of the roof.
Classification
Anatomy
Classification
Epitheliums can be classified on appearance or on function
Classification based on appearance
- Simple - one layer of cells
- Pseudostratified - looks like more than one layer but is not
- Stratified - more than one layer of cells
Simple epitheliums
Simple squamous epithelium
Cells are flat with bulging or flat nuclei. Lines the insides of lung alveoli and certain ducts in the kidney
Forms serous membranes called mesothelium that line cavities like: pericardial , peritoneal, plural
Lines blood vessels - known as endothelium
Simple cuboidal epithelium
It appears square in cross section, Found in: - Ducts of salivary glands, Follicles of the thyroid gland, Pigment layer in the eye, Collecting ducts of the kidney, In the middle ear is ciliated type.
Simple columnar
Lines the gastrointestinal tract from the stomach to the anal canal, Some columnar cells have a secretory function – stomach, peg cells in the oviduct, Some columnar cells have microvilli on their free border (striated border) – gall bladder, duodenum
Microvilli increase the surface area for absorption
Some columnar cells have cilia – oviduct, smaller bronchi
Cilia transport particles
Pseudostratified
Appears as stratified epithelium but all cells are in contact with the basement membrane. Has a thick basement membrane. Different cell types make up this epithelium, Cells that can be found in this type of epithelium are:
Columnar cells with cilia or microvilli.
Basal cells that do not reach the surface.
Goblet cells that secrete mucous.
Found in the trachea, epididymus, ductus deferens and female urethra
Stratified epithelium
Classified according to the shape of the surface cells
Stratified squamous epithelium
Has a basal layer that varies from cuboidal to columnar cells that divide to form new cells. Two types are found:
Keratinized: Mostly forms a dry covering, The middle layers consists of cells that are forming- and filling up with keratin. The superficial cells form a tough non living layer of keratin, Keratin is a type of protein, The skin is of this type has thick skin - found on the hand palms and soles of the feet, thin skin - found on the rest of the body
Non-keratinized: Top layer of cells are living cells with nuclei Forms a wet covering, The middle layers are polyhedral, The surface layer consists of flat squamous cells
Is found in: mouth, oesophagus, vagina
Stratified cuboidal epithelium
Found: - in the ducts of sweat glands
Stratified columnar epithelium
Found at the back of the eyelid (conjunctiva)
Transitional epithelium
- Sometimes the surface cells are squamous, sometimes cuboidal and sometimes columnar
- The superficial cells are called umbrella cells because they can open and close like umbrellas, when the epithelium stretch and shrink
- Umbrella cells can have 2 nuclei
- Found in the bladder and ureter