The ‘Lecture of the Month’ series introduces famous talks in the field of dermatology and plastic surgery in Korea. It provides a detailed look at the lecture our readers may have wanted to attend but could not due to a busy schedule. With this series, D&PS provides our readers a chance to enjoy important lectures at their convenience.

If you have lectures that you would like to learn about, please let us know. We will deliver the details of the lecture through our magazine.

The March issue features the talk of Dr. Ki-woong Hong of Samskin Plastic Surgery. Dr. Hong gave a talk at the Restylane User Meeting held on the 14th of last February. The gist of this talk will be presented in two articles; “Part 1: How to make an attractive face for Koreans through Harmony Programme” and “Part 2: How to improve perioral wrinkles including nasolabial folds and marionette lines based on filler and toxin treatment”.

 

Dr. Ki-woong Hong(Samskin Plastic Surgery)

Various dermal filler products are being developed and introduced in the market. This expanded the indications and usage of injectable dermal fillers. The following aspects should be considered for safe and effective use of dermal fillers with various ingredients and hardness in the Korean population.

First, we need to be aware of the difference between indications of dermal fillers recommended in the Western societies and the unique conditions of Korean patients to successfully perform total facial contouring with fillers. Simply speaking, it boils down to knowing the anatomical differences between Caucasians and Asians.

Caucasians generally have a narrower shape of the face with large features. They tend to prefer sharp angles and striking features. On the other hand, Asians have a flatter and more rounded shape of the face and tend to prefer a rounded and dainty outline of the face. Asians also prefer gentle curves of the facial outline rather than sharp protrusions. Additionally, Asians have thicker and harder skin than Caucasians and require a dermal filler with high viscosity and elasticity for overall volumization of the face. Asians are also more susceptible to serious vascular complications or necrosis due to tough subcutaneous tissues and complex vasculatures. Therefore, it is crucial to be aware of anatomically safe injection entry points and depth.

 

HELIOSⅡ/LOTUSⅡ/HYPERION – Manufacturer: LASEROPTEK(www.laseroptek.com)

 

Differences in the facial structure

 

Second, it is also important to consider racial differences in facial features. The ratios and proportions that Koreans view as ideal are as following.

The Western culture views that the ratio between the distance from trichion to glabella, from glabella to subnasale and from subnasale to gnathion should be 1:1:1. This ratio was followed in most aesthetic procedures. However, the recent trends in Korea favor shorter vertical length of the lower face as in babies. Lately, the preferred proportion of the lower face is only 0.8-0.9 of the mid face in the chin and jaw line procedures.

When dividing the face into five vertical sections from the right ear to the left ear, each fifth of the face should be of equal width. Special importance is given on the distance between the eyes and the width of the nose being about the same. This gives a balanced appearance to the entire face regardless of the absolute width of the right and left nostrils. Therefore, the dermal filler is increasingly used on the columella and the nasal tip to narrow the nostrils. In some cases, botulinum toxin injections are combined to adjust the muscles involved in flaring the nostrils in a smile or to pull the nasal tip downward. The right degree of protrusion of the mouth is determined based on the protrusion of the nasal tip and gnathion in the profile of the face. The line from the nasal tip to gnathion is called Rickett's line and it is used to assess the location of the nasal tip, lips and gnathion in relation with each other. In Caucasians, the ideal face has the lower lip situated 2mm posterior and the upper lip 4mm posterior to the Rickett's line. In Asians, these measurements would mean that the nasal tip and gnathion would protrude too much. Therefore, in an ideal Korean face, the lips should lie almost on the line that connects the nasal tip and gnathion. Following the latter standard will bring better results in Asians.

In a front view of the face, Koreans tend to prefer appropriately high cheekbones that create a subtle smile, rounded yet narrow outline of the face, symmetrical jawline, and proportionate shape and height of the nose bridge, etc. Hinderer proposed enhancing the upper lateral side of the cheekbones to create an apple cheek. However, the ogee curve should be more rounded in an Asian face and the medial lower cheekbones should be enhanced. Unlike Caucasians, most Asians have a wide and protruding zygomatic arch which does not need to be enlarged in lateral cheek hollow correction. Therefore, a corrective procedure should address the area under the arch.

Compared to Caucasians, Asians generally have a wider and more angular lower face in the shape of a heart or an inverted triangle. Most Asians prefer an inverted egg shape of the face but the lower face often widens with age due to sagging skin (Fig 1). To create a more convex and narrower shape of the face, dermal filler is combined with botulinum toxin or lipolytic agent to reduce the volume of the muscles, skin and soft tissues in the lateral cheek. When the jawline becomes angular due to sagging skin despite narrow bone structure, thread lift or laser tightening can also be combined to dermal filler to optimize the outcome.

 

The facial plane and amount of dermal filler

 

Third, I would like to emphasize the importance of using the right amount of filler in the right facial plane. As more air is needed to inflate the balloon, a larger amount of dermal filler may be needed to volumize a certain area. However, an excessive amount of filler injected into one area can interfere with the local blood circulation to cause various complications. Sometimes, post-injection molding performed to smooth the treatment area can compromise the volume enhancement or bring an undesired shape. The technique I use to bring maximal volumization with a low amount of filler is called dual plane remodeling (Fig 2). In dual plane remodeling, a hard dermal filler is injected into deeper layers such as the deep fat or submuscular layers for the purpose of local volumization and overall contouring. If the bumps or visible outlines of the filler appear on the skin surface, some may try molding or injecting more filler to smooth the surface. However, hard fillers are not easily controlled by molding and excessive molding can cause the filler to migrate. Also, a large amount of filler injected into one area can cause various problems. Therefore, a soft HA filler with small particles should be injected into the subdermal layers including the upper dermis in the tenting technique. This technique allows only a small amount of filler to be used and prevent the risk of excessive molding. It also has economic benefits as it does not create noticeable boundaries of the filler and eliminates the need for additional injections.

One may be concerned that the superficial injection of HA filler loses volume quickly and may create bumps. However, the subdermal layer including the upper dermis has histological characteristics that retain the injected filler for a longer period of time compared to other layers. The added benefit of this method is that the HA filler injected into the subdermal layer does not interact with other fillers when combining various types of fillers.

 

-To be continued-