# The term ‘Orthodontics’ was coined by:
A. Le Foulon
B. Hunter
C. Carabelli
D. Norman Kingsley
The correct answer is A. Le Foulon.
The term orthodontics was apparently used first by the Frenchman Le Foulon in 1839.
The occipital condyle is represented by the following cephalometric point:
# The occipital condyle is represented by the following cephalometric point:
A. Bolton’s point
B. Broadbent registration point
C. Basion
D. Articulare
The correct answer is A. Bolton's point.
Bolton's point: The highest point at the post-condylar notch of occipital bone
Few other cephalometric landmarks are:
1. Glabella: It is the most prominent point on the forehead in the mid-sagittal plane.
2. Nasion: The most anterior point midway between the frontal and nasal bone on the frontonasal suture.
3. Orbitale: The lowest point on the inferior bony margin of the orbit.
4. Porion: The highest bony point on the upper margin of external auditory meatus.
5. Sella: This point represents the mid point of the pituitary fossa or sella-turcica.
6. Basion: It is median point of the anterior margin of the foramen magnum
7. Anterior nasal spine: It is the anterior tip of the sharp bony process of the maxilla in the midline of the lower margin of anterior nasal spine.
8. Point A: It is a deepest point in the midline between the anterior nasal spine and alveolar crest between the two central incisors. It is also called as " subspinale".
9. Prosthion: The lowest and the most anterior point on the alveolar bone in the midline between the upper central incisors. It is also called as " supradentale".
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10. The key ridge: The lower most point on the contour of anterior wall of the infra-temporal fossa.
11. Posterior nasal spine: The intersection of a continuation of the the anterior wall of the pterygopalatine fossa and the floor of the nose, marking the distal limit of the maxilla.
12. Broadbent registration point: It is the midpoint of the perpendicular from the centre of the sella turcica to the Bolton point.
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13 PTM point: It is the intersection of the inferior border of foramen rotundum with posterior wall of the pterygo maxillary fissure.
14. Chelion: It is the lateral terminus of the oral slit on the slit on the outer corner of the mouth.
15. Subnasal: The point where the lowest border of the nose meets the outer contour of the upper lip.
16. Point B: It is the deepest point in the midline between the alveolar crest of mandible and the mental process. Also called as " submentale".
17. Gonion: It is a constructed point at the junction of ramal plane and the mandibular plane.
18. Pogonion: It is the most anterior point of the bony chin in the median plane.
19. Menton: It is the most inferior midline point on the mandibular symphysis.
20. Gnathion: It is the most antero-inferior point on the symphysis of the chin. It is constructed on the symphysis of the chin, by intersecting a line drawn perpendicular to the line connecting menton and pogonion.
21. Articulare: It is a point at the junction of the posterior border of ramus and the inferior border of the basilar part of the occipital bone.
22. Condylion: The most superior point on the head of the condyles.
23. Infradentale: The highest and the most anterior point on the alveolar process, in the median plane between the mandibular incisors.
Termination of skeletal maturity - Indicator
# Which of the following bone indicates the termination of skeletal maturity?
A. Presence of Sesamoid
B. Appearance of pisiformis
C. Appearance of calcification of hook of hamate
D. Union of diaphysis and epiphysis on radius
The correct answer is D. Union of diaphysis and epiphysis on radius.
Some other important tips:
* Absence of hamate and pisiform - Still 1 year for prepubertal growth spurt
* Presence of hamular process of the hamate, pisiform and sesamoid- Beginning of growth spurt
* Initial ossification of sesamoid - Peak pubertal growth spurt
* The epiphysis and diaphysis fusion/ ossification of sesamoid completed - Prepubertal growth spurt completed
* The epiphysis and diaphysis fusion on radius and ulna- Active growth completed
Fishman’s index is used in relation with:
# Fishman’s index is used in relation with:
A. Population
B. Hand-wrist radiographs
C. Cephalograms
D. Periodontal diseases
The correct answer is B. Hand-wrist radiographs.
The following are the most commonly used methods for determination of skeletal maturity through hand-wrist xrays:
- Atlas method by Greulich and Pyle
- Bjork Grave and Brown method
- Singer's method of assessment
- Fishman's skeletal maturity indicators
- Hagg and Taranger method
Carpal radiograph is used for assessment of:
# Carpal radiograph is used for assessment of:
A. Bone condition
B. Chronological age
C. Treatment plan
D. Skeletal maturation
The correct answer is: D. Skeletal Maturation.
There are different methods to assess the skeletal maturity of an indivudual which include:
1. Use of hand wrist radiographs
2. Evaluation of skeletal maturation using cervical vertebrae
3. Assessment of maturity by clinical and radiographic examination of different stages of tooth (Lower third molar)
Hand wrist radiograph is the most reliable among all these.
Vestibuloplasty procedure
# A vestibuloplasty procedure is performed by:
A. Reducing buccal bone from the alveolar ridge with a barrel bur and a handpiece
B. Apically repositioning the muscular and mucosal attachments of the mandible
C. Reflecting the gingiva and using Rongeurs to remove bone from the alveolar crest
D. Using a bone file to smooth rough bony projections
E. Grafting harvested iliac or rib bone onto the alveolar process
The correct answer is B. Apically repositioning the muscular and mucosal attachments of the mandible
Vestibuloplasty is a procedure performed to lengthen the residual ridge and deepen the oral vestibule.
A vestibuloplasty can only be achieved by relocating or repositioning the muscle attachments and mucous membrane covering it into a deeper or more apical position.
Vestibuloplasties are also accompanied with the use of a mucosal graft or a skin graft.
Most ideal finish line configuration for a porcelain veneer:
# The most ideal finish line configuration for a porcelain veneer is:
A. Feather
B. Chamfer
C. Shoulder
D. Chisel
The correct answer is: C. Shoulder.
#Shoulder Finish Line
Indications: • All ceramic crowns • PFM crowns • Injectable porcelains
Advantages: • Good crown contours • Esthetics • Less distortion • Provides adequate bulk
Disadvantages: • Least conservative • Inferior marginal adaptation
# Shoulder with bevel Finish Line
Indications: • Proximal boxes of onlays and inlays • Labial finish line of metal ceramics • Occlusal shoulder of onlays
Advantages: • Superior marginal adaptation • Resists distortion • Facilitates removal of unsupported enamel rods
Disadvantages: • Requires subgingival extension • Detection of post cementation caries is difficult
# Chamfer Finish Line
Indications: • Cast metal restorations • Lingual aspect of metal ceramics
Advantages: • Conservative • Good marginal adaptation • Provides bulk
Disadvantages: • Improper fabrication may result in an unsupported tip
# Knife edge Finish Line
Indications: • Young patients • MOD onlay • Inaccessible areas • Finish lines in cementum
Advantages: • Conservative • Ideal for marginal adaptation
Disadvantages: • Does not provide a distinct finish line • Waxing, polishing and casting becomes critical • Overcontoured restoration in an attempt to obtain bulk
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