Dr. Raman Dhungel, BDS (BPKIHS), MDS Resident Department of Orthodontics, BPKIHS Dharan Contact Number

If you need to arrange / reschedule any appointment with Dr. Raman Dhungel,  BDS (BPKIHS), MDS Resident Department of Orthodontics, BPKIHS Dharan, then you can message on Whatsapp (+9779803027654) or call on +9779803027654/+9779849510059. Call only when absolutely necessary and preferably at 6:00 PM to 8:00 PM. 

Difference in the amount of space needed for the accommodation of the incisors and amount of space available for them is known as:

Difference in the amount of space needed for the accommodation of the incisors and amount of space available for them is known as:

A. Primate space

B. Leeway Space of Nance

C. Anthropoid space

D. Incisal liability

D. Incisal liability

Incisal liability, also known as incisor liability, describes the space discrepancy in the mixed dentition phase where the permanent incisors require more mesiodistal width (typically 7 mm in the maxillary arch and 5 mm in the mandibular arch) than the primary incisors they replace, creating a potential crowding issue that must be accommodated by factors like interdental spacing, arch perimeter changes, or leeway space. This is distinct from primate space (A, developmental space distal to the lateral incisor), leeway space of Nance (B, difference between deciduous and permanent molars/canines), and anthropoid space (C, a less common term sometimes used interchangeably with primate space in non-human primates). 

Type of crowding that is genetically determined and is caused by disproportionately sized teeth and jaws:

Type of crowding that is genetically determined and is caused by disproportionately sized teeth and jaws:

A. Primary crowding

B. Secondary crowding

C. Tertiary crowding

D. Environmental crowding

The correct answer is A. Primary crowding. 

Primary crowding refers to a type of dental crowding caused by a genetic discrepancy in tooth and jaw sizes, such as larger teeth relative to the jaw, leading to misalignment. This contrasts with secondary crowding, which results from environmental factors like early tooth loss, and tertiary crowding, which involves late-stage incisor irregularities. Environmental crowding isn't a standard classification but aligns with secondary causes.

Which of the following is the least biocompatible?

Which of the following is the least biocompatible?

A. TMA

B. Elgiloy

C. Stainless steel

D. Cu-NiTi

The correct answer is B. Elgiloy.

Elgiloy (a cobalt-chromium-nickel alloy) is the least biocompatible among the options due to its higher nickel content (14-16%) compared to stainless steel (8%), leading to greater nickel and chromium ion release in simulated oral environments. Studies show it induces significant neurotoxicity via necrosis, elevated oxidative stress, and higher cytotoxicity (2.7-fold increase in dead cells) relative to stainless steel (apoptosis, 1.7-fold dead cells), TMA (variable but generally low ion release and non-toxic), and Cu-NiTi (lower ion release and minimal cytotoxicity). This increases risks of allergic reactions and tissue irritation in orthodontic use.