The nose is made up of a fixed and rigid part that is called nasal pyramid, although it rather has the shape of a tent or roof, and a pliable mobile part which is the nasal tip, the alae and its annexes. The nasal pyramid is formed by two types of structures or tissues; in the most cephalic or upper part the nasal pyramid is formed by the nasal bones and the ascending process of the maxilla, that is, by bone tissue; the most caudal or lower part of the nasal pyramid is formed by the triangular cartilages or also called quadrangular or lateral or upper lateral, that is, by cartilaginous tissue.
Both halves or walls of the nasal pyramid join and fuse horizontally with each other in the center of the nose to form the dorsum, hump or nasal bridge (misnamed by many people as the septum, which is not part of the nasal dorsum), creating what is called pyramid or bony or osseous or hard dorsum (cephalic or upper), formed by synostosis or fusion between bones, and the cartilaginous middle vault or soft pyramid or dorsum (caudal or lower), formed by synchondrosis or fusion between cartilages. In turn, the nasal dorsum is joined and merged by its lower or posterior face with the nasal septum, nasal septum which also, in turn, consists of a cephalic or upper bony part and a caudal or lower cartilaginous part, corresponding the bony septum to the fusion with the cephalic or upper or bony dorsum and the cartilaginous septum to the fusion with the caudal or lower or cartilaginous dorsum, forming a tripod in which the lateral legs are the nasal wall and the central leg the nasal septum.
The nasal tip and the alae are structured by the so called alar or lower lateral horseshoe shaped cartilages with their lateral and medial crura or crus and accessory cartilages, the domes between lateral and medial cruras, the interdomal fibrofatty pad, the caudal or lower septum and the skin of the alae.
Both halves of the nasal tip join with each other in the center of the tip to form a tripod in which the lateral legs are the lateral cruras of the alar or lower lateral cartilages and the central leg the union of both medial cruras of the alar or lower lateral cartilages.
A canonically balanced nose is that having the tip projection at the same or close to same level than the caudal or lower dorsum or supratip, building an optimal balance between the tip domes and the caudal or lower septum of the middle vault dorsum surface. However, some noses gather very specific features to become the so called tension nose, like caudal and dorsal septum hypertrophy, hypertrophic alar or lower lateral cartilages, a prominent caudal or lower cartilaginous bridge hump, protruding and overprojected tip, protrusion of the nose on the upper lip or philtrum, prominent nasal spine, blunt transition and short distance between columella and upper lip, all due to septum and other cartilages overgrowth, which creates a relative shortfall of skin thus tensioning the nose, being narrow the nasal pyramid and showing a relative polly beak deformity.
Very specific custom structure rhinoplasty techniques have to be applied to correct such effect, combining either alar or lower lateral cartilages trimming and plasties, plications (shaping sutures through the cartilages), nasal tip grafting, septum shortening, nasal spine reduction, tongue in groove maneuver, with or without reinforcement of tip support with columellar strut, and of course suitable shaving the dorsum to the desired level.