The position of the maxillary canines and first permanent molars relative to the mandibular canines and first permanent molars

SOLUTION

The key to success is to use an appliance that is both comfortable, easily retained and predictable such as a simple Hawley retainer with recurve springs or a fixed labial-lingual appliance (including a vertical removable arch for ease of adjustment with a recurve spring to jump the cross-bite). 

Both of these appliances work by tipping the maxillary teeth forward so they are in a normal dental relationship to the mandibular teeth. Once this is accomplished, it will allow future coordinated growth between the maxilla and the mandible

SOLUTION 

Angle of Convexity The angle of convexity is formed by the intersection of line from N to point A, to point A to pogonion.

SOLUTION

The reason is found in the concept of "dental compensation for skeletal discrepancy.  This can occur naturally as well as being created by orthodontic camouflage treatment.

In mandibular prognathism, for instance, as the individual grows the upper incisors tend to protrude while the lower incisors incline lingually.

By the time growth is completed, the dental discrepancy usually is smaller than the jaw discrepancy. 

Tooth position has compensated at least partially for the jaw discrepancy.

Explanation: The philtrum is the vertical groove located in the middle of the upper lip. It is primarily formed by the fusion of the medial nasal processes, which include the globular process. The globular process is a key structure in the embryonic development of the face, contributing to the formation of the upper lip and the philtrum.