Rotational force of extraction is used for delivery of which tooth out of the socket?

 # Rotational force of extraction is used for delivery of which tooth out of the socket?

A. Upper central incisors and lower premolars

B. Upper centrals and lateral incisors

C. Upper and lower central incisors

D. Upper premolars and lower central incisors

The correct answer is A. Upper central incisors and lower premolars.

Rotational pressure, as the name implies, rotates the tooth, which causes some internal expansion of the tooth socket and tearing of periodontal ligaments. Teeth with single, conical roots (such as maxillary incisors and mandibular premolars) and those with roots that are not curved are most amenable to luxation by this technique. Teeth that have other than conical roots or that have multiple roots—especially if those roots are curved—are more likely to fracture under this type of pressure.

Ref: Contemporary Oral and Maxillofacial Surgery 6th Edition, Hupp

Metapex is a combination of:

 # Metapex is a combination of: 

A. Calcium hydroxide + ZOE

B. ZOE + Iodoform

C. Calcium hydroxide + Iodoform

D. Calcium hydroxide + GIC

The correct answer is C. Calcium hydroxide + Iodoform.

Metapex = Calcium hydroxide + iodoform 

Vitapex = Calcium hydroxide + iodoform + Silicon based oil (better flow able property) 

• Ideal material for obturating primary teeth = same resorption rate as of primary tooth roots 

• Both Vitapex & metapex has same resorption rate to primary tooth root but due to better flow able property of vitapex its nearly IDEAL and best material for obturation in primary teeth. 

The condylar cartilage in the mandible is held to be a:

# The condylar cartilage in the mandible is held to be a: 

A. Primary cartilage

B. Secondary cartilage

C. Tertiary cartilage

D. Non growing cartilage

The correct answer is B. Secondary cartilage.

Meckel's cartilage is the primary cartilage of mandible. The cartilages at the condyle, coronoid and symphysis are the secondary cartilages. The condylar cartilage is considered as the pacemaker for growth of that bone. Nasal septum is considered as the pacemaker for growth of maxilla. 

In Peck and Peck index, mesiodistal and buccolingual measurements of which of the following tooth is taken:

 # In Peck and Peck index, mesiodistal and buccolingual measurements of which of the following tooth is taken: 

A. Maxillary central incisor 

B. Mandibular central incisor

C. Maxillary premolars 

D. Mandibular molars 

The correct answer is B. Mandibular central incisor.

Peck and Peck index: 

The mandibular incisors in persons with no crowding will have smaller mesiodistal width and large labiolingual width than in persons with incisal crowding.

The proportion of the mesiodistal width of each tooth to the labio lingual thickness is calculated using the formula:

M.D.W./L.L.W x100 

Mean value for lower central incisor should be 88 to 92%. 

Mean value for lower lateral incisor should be 90 to 95% 

If the calculated value is greater than mean value, it indicates that the mesiodistal width is more than labiolingual width and hence proximal stripping is indicated. 

Care 32 Dental, Changunarayan 2, Bhaktapur

 Name of Dental Clinic: Care 32 Dental

Address (Full): Changunarayan 2, Bhaktapur

Year of Establishment: 2080

Name of the chief Dental Surgeon: Dr. Sabin Gwachha, Dr. Anamol Dumaru

CONTACT NUMBER: 9813510103

NMC Number of Dental Surgeon: 30599

CLICK HERE TO VIEW ALL DENTAL CLINICS OF BAGMATI PROVINCE

According to Edward H. Angle's classification of malocclusion, what is the defining characteristic of Class III malocclusion?

 # According to Edward H. Angle's classification of malocclusion, what is the defining characteristic of Class III malocclusion?

A) Normal relationship of the molars but malposed teeth

B) Lower molar distally positioned relative to the upper molar

C) Lower molar mesially positioned relative to the upper molar

D) Correct line of occlusion with rotated teeth

The correct answer is C. Lower molar mesially positioned relative to the upper molar.

Angle’s classification of malocclusion in the 1890s was an important step in the development of orthodontics because it not only subdivided major types of malocclusion but also included the first clear and simple definition of normal occlusion in the natural dentition. Angle’s postulate was that the upper first molars were the key to occlusion and that the upper and lower molars should be related so that the mesiobuccal cusp of the upper molar occludes in the buccal groove of the lower molar. If the teeth were arranged on a smoothly curving line of occlusion and this molar relationship existed, then normal occlusion would result. This statement, which 100 years of experience has proved to be correct except when there are aberrations in the size of teeth, brilliantly simplified normal occlusion.

Angle then described three classes of malocclusion, based on the occlusal relationships of the first molars:

• Class I: Normal relationship of the molars, but line of occlusion incorrect because of malposed teeth, rotations, or other causes

• Class II: Lower molar distally positioned relative to upper molar, line of occlusion not specified

• Class III: Lower molar mesially positioned relative to upper molar, line of occlusion not specified

Ref: Proffit, W. R., Fields, H., Msd, D. M., Larson, B., & Sarver, D. M. (2019). Contemporary Orthodontics, 6e: South Asia Edition-E-Book. Elsevier India.

What was Norman Kingsley's contribution to orthodontics during the latter half of the 19th century?

 # What was Norman Kingsley's contribution to orthodontics during the latter half of the 19th century?

A) He developed the first orthodontic appliances in Greek materials.

B) He was among the first to use extraoral force to correct protruding teeth.

C) He introduced the concept of occlusion in the natural dentition.

D) He focused on the removal of teeth for various dental problems.

The correct answer is B. He was among the first to use extraoral force to correct protruding teeth.

After 1850 the first texts that systematically described orthodontics appeared, the most notable being Norman Kingsley’s Oral Deformities. Kingsley, who had a tremendous influence on American dentistry in the latter half of the 19th century, was among the first to use extraoral force to correct protruding teeth. He was also a pioneer in the treatment of cleft palate and related problems.

Ref: Proffit, W. R., Fields, H., Msd, D. M., Larson, B., & Sarver, D. M. (2019). Contemporary Orthodontics, 6e: South Asia Edition-E-Book. Elsevier India.