Test on Congenital Craniofacial Clefts: Etiology and Treatment

Question 1: Is it believed that all of the craniofacial skeleton is formed by neural crest cells?

A. Yes

B. No

Explanation: The study materials state that "Most of the craniofacial skeleton is believed to be formed by these neural crest cells," indicating that not all of it is believed to be formed by them.

Question 2: According to the study materials, how has the perception of Tessier's classification system evolved among embryologists and geneticists in relation to embryologic developmental theories?

A. Tessier's classification was immediately and widely accepted by embryologists and geneticists due to its clear correlation with existing embryologic theories.

B. Embryologists and geneticists were initially hesitant to accept Tessier's classification because it did not align with existing embryologic developmental theories.

C. The consistency of newer neuroembryologic theories has reinforced the importance of Tessier's descriptions, making its value more apparent to embryologists and geneticists.

D. Tessier's classification, while useful for surgeons, has never found a basis in embryologic development and remains unsupported by geneticists.

Explanation: The study materials state that 'geneticists and embryologists have been slow to embrace his numeric organization of craniofacial clefts because it could not previously be understood by existing theories of embryologic developmental.' This indicates initial hesitation. However, with the progression of newer neuroembryologic theories, 'The consistency of these newer neuroembryologic theories with Tessier’s classification of craniofacial clefts reinforces the importance of Tessier’s descriptions' and 'the value of Tessier’s organization of rare craniofacial clefts should become apparent to embryologists and geneticists.'

Question 3: The number 3 Tessier craniofacial cleft is also commonly known as a Tessier frontozygomatic cleft.

A. Yes

B. No

Explanation: The study materials state that the number 3 Tessier craniofacial cleft is also referred to as a Tessier oronaso-ocular cleft. A frontozygomatic cleft located at the lateral canthus is identified as a number 8 cleft in the study materials, not a number 3 cleft.

Question 4: Which of the following are osseous anomalies typically associated with a Tessier number 7 cleft?

A. The skeletal cleft passes between the lateral incisor and the canine.

B. The posterior maxilla and mandibular ramus are hypoplastic in the vertical dimension.

C. The zygomatic arch may be disrupted, represented by a small stump.

D. The anterior maxillary arch is typically flat.

Explanation: According to the study materials, osseous anomalies in a number 7 cleft include the posterior maxilla and mandibular ramus being hypoplastic in the vertical dimension, and the zygomatic arch being disrupted and represented by a small stump in severe forms. The skeletal cleft passing between the lateral incisor and canine, and the anterior maxillary arch being flat, are characteristics of other cleft types, not specifically number 7.

Question 5: The cephalad progression of the number 5 cleft is the number 9 cleft.

A. Yes

B. No

Explanation: The cephalad progression of the number 5 cleft is the number 9 cleft.