Modification of Adam's clasp with distal extension

  In orthodontics, the modification of Adam's clasp with distal extension refers to a technique where the distal end of the Adam's clasp is extended to engage elastics or auxiliary components.

Adam's clasp is a commonly used intraoral auxiliary component in orthodontic treatment. It consists of a rectangular wire arm that extends from the buccal surface of a molar tooth and curves occlusally to engage an undercut on an adjacent tooth. It provides anchorage and stability to the orthodontic appliance or archwire.

The modification of Adam's clasp with distal extension involves extending the clasp arm distally beyond the last tooth involved in the clasp. This extended portion is used to attach elastics, which are commonly used in orthodontics to apply additional forces and aid in tooth movement.

The distal extension of Adam's clasp allows for the placement of elastics from the extended arm to various areas in the mouth, such as hooks on brackets or other auxiliary attachments. The elastics exert the desired force vectors, assisting in achieving the desired tooth movements and occlusal adjustments.

By incorporating the distal extension into the Adam's clasp design, orthodontists can apply forces in different directions to address specific tooth movements, such as closing gaps, correcting malocclusions, or aligning the bite. It provides versatility in treatment mechanics and enhances the precision and control of orthodontic tooth movements.

It's important to note that the modification of Adam's clasp with distal extension is specific to certain orthodontic cases and treatment plans. The decision to utilize this modification is made by the orthodontist based on the individual patient's needs and treatment goals.

In summary, the modification of Adam's clasp with distal extension in orthodontics involves extending the clasp arm beyond the last tooth to engage elastics. This modification allows for the application of additional forces to achieve specific tooth movements and optimize treatment outcomes.

Sensory nerve supply to the base of the tongue:

 # Sensory nerve supply to the base of the tongue:

A. Facial nerve

B. Trigeminal nerve

C. Glossopharyngeal nerve

D. Optic nerve

The correct answer is C. Glossopharyngeal nerve.

The hypoglossal nerve (CN XII) provides motor innervation to all of the intrinsic and extrinsic muscles of the tongue except for the palatoglossus muscle, which is innervated by the vagus nerve (CN X). It runs superficial to the hyoglossus muscle. Lesions of the hypoglossal nerve cause deviation of the tongue to the ipsilateral (i.e., damaged) side.

Taste to the anterior two-thirds of the tongue is achieved through innervation from the chorda tympani nerve, a branch of the facial nerve (CN VII). General sensation to the anterior two-thirds of the tongue is by innervation from the lingual nerve, a branch of the mandibular branch of the trigeminal nerve (CN V3). The lingual nerve is located deep and medial to the hyoglossus muscle and is associated with the submandibular ganglion.

On the other hand, taste perception in the posterior third of the tongue is accomplished through innervation from the glossopharyngeal nerve (CN IX), which also provides general sensation to the posterior one-third of the tongue. Taste perception also is performed by both the epiglottis and the epiglottic region of the tongue, which receives taste and general sensation from innervation by the internal laryngeal branch of the vagus nerve (CN X). Damage to the vagus nerve (CN X) causes contralateral deviation (away from the injured side) of the uvula.

Reference: Dotiwala AK, Samra NS. Anatomy, Head and Neck, Tongue. [Updated 2022 Aug 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507782/

Sensory nerves supply to the body of the tongue:

 # Sensory nerves supply to the body of the tongue:

A. Optic nerve

B. Trigeminal nerve

C. Facial nerve

D. Glossopharyngeal nerve

The correct answer is B. Trigeminal nerve.

The hypoglossal nerve (CN XII) provides motor innervation to all of the intrinsic and extrinsic muscles of the tongue except for the palatoglossus muscle, which is innervated by the vagus nerve (CN X). It runs superficial to the hyoglossus muscle. Lesions of the hypoglossal nerve cause deviation of the tongue to the ipsilateral (i.e., damaged) side.

Taste to the anterior two-thirds of the tongue is achieved through innervation from the chorda tympani nerve, a branch of the facial nerve (CN VII). General sensation to the anterior two-thirds of the tongue is by innervation from the lingual nerve, a branch of the mandibular branch of the trigeminal nerve (CN V3). The lingual nerve is located deep and medial to the hyoglossus muscle and is associated with the submandibular ganglion.

On the other hand, taste perception in the posterior third of the tongue is accomplished through innervation from the glossopharyngeal nerve (CN IX), which also provides general sensation to the posterior one-third of the tongue. Taste perception also is performed by both the epiglottis and the epiglottic region of the tongue, which receives taste and general sensation from innervation by the internal laryngeal branch of the vagus nerve (CN X). Damage to the vagus nerve (CN X) causes contralateral deviation (away from the injured side) of the uvula.

Reference: Dotiwala AK, Samra NS. Anatomy, Head and Neck, Tongue. [Updated 2022 Aug 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507782/

From which arch is hypobranchial eminence derived?

 # Hypobranchial eminence is derived from:

A. 1st arch 

B. 2nd arch

C. 3rd arch 

D. 4th arch

The correct answer is C. 3rd arch.

During embryonic development, the pharyngeal arches play a crucial role in the formation of various structures in the head and neck region. The third pharyngeal arch gives rise to several important structures, including the hyoid bone, the posterior one-third of the tongue (base of the tongue), and the associated muscles and nerves.

The hypobranchial eminence is a swelling within the third pharyngeal arch that contributes to the formation of the base of the tongue. It gives rise to the posterior part of the tongue, while the anterior part of the tongue is formed by the first pharyngeal arch.

Therefore, the correct option is C. 3rd arch.