Nose muscular dynamics: the tip trigonum.

In 1995, the senior author (E.E.F.) published an article in which he described the musculus digastricus septi nasi labialis. In the article presented here, work carried out by anatomists and other researchers who, over the last two centuries, studied nose muscular dynamics is described. The present study is based on Gray's Anatomy, which, in 1858, first described the nasal tip muscles, along with the other nasal muscles. Later works not only used different terminology for these muscles but also ignored some, creating tremendous confusion. The study presented here provides an update of the exact terms, location, insertions, and muscle functions of the muscles of the nose. Each nose muscle is described with regard to the two portions able to produce separate contractions. In this study, the term "dual function" is used and characterizes the nasal mimetic muscles that do not have well-defined fascia. Therefore, there is doubt about the existence of a real nasal superficial muscle aponeurotic system. The musculus myrtiformis seems to have a dual function, inserting in the canine fosse and in the periosteum of the central incisors, forming two portions-one to the septum and the other to the nostril-each of which has specific functions. This study has been based on research in physiognomy, the science of expression. With regard to the basis for nose expressions, common anatomical research is excluded because it provides a different view of the dynamics studied to date. The term trigonum musculare apicis nasi defines the interaction of the musculi compressor narium minor and dilator naris anterior, connecting with the columellar bundle of the musculus digastricus and levering the nasal spine. This muscular trigone creates circular concentric and eccentric movements of the nasal tip.