Introduction: the "science of choice" you have not been told until now
Every time you look in the mirror, do you sigh, "If only this were a little higher," "If only this wrinkle weren't here"?
In fact, the way to solve that worry already exists. But the issue is not "whether to do it or not," it is"what, where, and at what firmness to put in"— the fact that the precision of this choice greatly affects satisfaction.
- The truth of the overwhelming safety and patient satisfaction of hyaluronic acid filler, proven by the latest clinical data
- The medical criteria for choosing the optimal hyaluronic acid product for the target area, such as viscoelasticity (firmness) and cross-linking technology
- The complete manual, recommended by specialists, of accurate injection volume, angle, and needle choice in high-difficulty areas (especially the nose)
- The risk-avoidance measures you should absolutely know before the procedure, in order to prevent serious complications such as blindness and skin necrosis
Anyone is bound to feel anxious about a first filler injection. But if you have correct knowledge based on the latest medical data, you can safely approach your ideal self while keeping risk to a minimum. By the time you finish reading this article, you should feel, "Why did no one ever tell me this?"
94.94% — the overwhelming approval rate and satisfaction of hyaluronic acid, told by the data
First, let's start with this number.
There is a solid reason why so many people around the world choose the non-surgical approach. The fact that an enormous number of patients have already safely resolved their hang-ups through filler injection without a scalpel backs up its reliability.
According to the comprehensive systematic review by Williams et al., from 4,632 studies extracted in the initial search, 23 studies selected by rigorous criteria were analyzed. In data on a total of 1,600 patients, the most frequently used in non-surgicalrhinoplastywas hyaluronic acid, used in1,174 patients, equivalent to 73.38% of the whole. Next were calcium hydroxylapatite at 12.44% (199 people), botulinum toxin at 7.69% (123 people), collagen of porcine or bovine origin at 3.69% (59 people), and other materials at 2.81% (45 people (Williams 2020)). In another analysis as well, hyaluronic acid was used in 28 (75.67%) of all 37 studies, while calcium hydroxylapatite was limited to 7 (18.92% (Devictor 2021)).
So how do the patients who actually received it feel — that's the part you're most curious about, right?
Patients' overall satisfaction recorded the astounding figure of94.94%. In 20 studies (1,511 people in total), surveys were conducted between 14 days and 18 months after injection. Short-term satisfaction under 6 months was 95.19% in 14 studies (1,415 people), and long-term satisfaction of 6 months or more was 89.58% in 6 studies (96 people). The p-value for this short-vs-long difference was 0.017, and the 95% confidence interval was 0.77% to 13.43% (Williams 2020). In a study of more than 250 Swedish people, the effect lasted from 1 year to a maximum of 5 years, and in a study of 280 Chinese women, good results were maintained for as long as 9 months. The effect ofhyaluronic acid injectionin the nose lasts longer than at other facial areas, and in some areas it may last 2 to 3 years (Trevidic 2022). There are also products for which a treatment duration of 12 months (Harb 2020) was assumed.
The numbers tell the story. But to achieve high satisfaction, there is one more "core" you must know — that is "the choice of firmness."
"What happens if you get the firmness wrong" — why viscoelasticity and product choice divide the result
Any hyaluronic acid is the same — if you think so, that is a dangerous misunderstanding.
Hyaluronic acid is composed of a component called glycosaminoglycan, in which d-glucuronic acid and N-acetyl-d-glucosamine — which originally exist in the human body — are alternately linked (Trevidic 2022). When choosing a product, its biophysical properties, especially elasticity and cohesivity, become extremely important.
For example — for an area that needs to maintain its shape, like the nose, a product with high elasticity and cohesivity is indispensable (Trevidic 2022). If you inject a too-soft product into the nose, its shape collapses under gravity and the pressure of daily movement, and you cannot get the result you envisioned. Conversely, putting a firm product into a mobile area like the lips or the tear-trough (aegyo-sal) becomes a cause of unnatural firmness or unevenness.
That is precisely why the evolution of products matters. In the latest products, gels have been developed that keep the cross-linking density low while enhancing adaptability to the tissue and giving higher cohesivity. For example, Vycross technology, which combines high- and low-molecular-weight hyaluronic acid, was reported to be used in 2 studies (154 patients in total (Williams 2020)). Furthermore, high-viscosity products such as Teosyal Ultradeep 25 mg/ml and Perfectha Subskin 20 mg/ml (Harb 2020) are chosen for their excellent durability and reversibility. Owing to these rheological (flow-science) properties, even under physical stress such as stretching and compression of the skin, the product adapts to the surrounding environment and can maintain its shape over a long period (Trevidic 2022).
And there is one more point in product selection that absolutely cannot be left out — that is "reversibility."
The greatest reason hyaluronic acid is overwhelmingly recommended is that, by using a dissolving injection called hyaluronidase, you can respond quickly even to a complication in the unlikely event. In fact, of 19 patients who suffered vascular disorders,permanent sequelae were successfully prevented in 16. By contrast, in a study conducted at a private clinic in Germany, of 26 people who used calcium hydroxylapatite, 1 moderate and 2 severe complications occurred, whereasamong the 20 people who used hyaluronic acid, there were 0 complications (Trevidic 2022). The overall data also show that the complication rate of calcium hydroxylapatite is about 10 times higher than that of hyaluronic acid (Williams 2020). To deliver a reliable result with one cycle (Carruthers 2010) of treatment while also safeguarding against risk, hyaluronic acid is the optimal choice.
So let's look at the concrete injection criteria for the area of the highest difficulty and the one most people are concerned about — the "nose."
The complete filler guide by area: the nose (non-surgical rhinoplasty) edition
"Put in more and it gets higher" — this assumption can sometimes invite an irreversible result.
The careless thought that "just inject a bit more and it'll get higher" is very dangerous. Top specialists, based on anatomy, rigorously define the 'golden standard' of an extremely safe and meticulous injection volume, angle, and depth. Undergoing a procedure without knowing this standard is not recommended.
First, let's confirm from the number of "how much volume is used."
Regarding the concrete injection volume, in data on 242 Korean patients, injection into the nasal dorsum was in 112 people (46.3%) with an average of1.0 ± 0.4 ml, injection for the purpose of tip rotation was in 8 people (3.3%) with an average of 0.9 ± 0.3 ml, and injection into the whole nose was in 122 people (50.4%) with an average of 1.6 ± 0.5 ml (Trevidic 2022). On the other hand, the average injection volume in the 11 studies (512 people) in the review by Williams (2020) et al. was limited to0.54 ml (Williams 2020), proving that even an extremely small injection can produce a visual change. In a study of 5,000 people, the most common treatment indication was correction of the hump (a stepped nose), accounting for 44% of the whole (Harb 2020).
Many people are surprised here — but the "injection volume per session" at the expert level is a far smaller amount than you would imagine.
In the expert consensus, to prevent misinjection into a blood vessel,microdeposits (micro-injections) of 0.1 ml or less per injection, ideally less than 0.05 ml,are recommended. The general injection volume into the columella is 0.2 to 0.3 ml. In an actual case of a 28-year-old woman, 0.1 ml into the anterior nasal spine, 0.2 ml into the columella, 0.15 ml into the nasal dorsum, and 0.05 ml into the infratip lobule (Trevidic 2022) were injected, successfully achieving extremely precise contouring.
Not only volume, but "angle and depth" are equally important.
As an injection technique, it is recommended that the needle's entry angle be a diagonal of about 30 to 45 degrees, and that during injection the needle be bent to about 60 degrees and advanced from the cranial to the caudal side. To lower vascular risk,injection into the deepest layer, supraperiosteal or supraperichondrial, is essential. As instruments, 22- to 30-gauge needles or cannulas are used. In one technique, a 26-gauge needle pierces the skin, and then a switch is made to a 23-gauge (Williams 2020) blunt cannula to prevent vascular injury. Among Korean specialists, short 27-gauge needles tend to be preferred. Prior computer simulation has an accuracy of 86% (Trevidic 2022) and is useful for planning.
As for the postoperative course, touch-ups (fine adjustments) should be done 2 to 4 weeks later (Williams 2020), or at least 2 weeks (Trevidic 2022) afterward. ...
An approach based on the bone-structure characteristics of Asians
...
@@INFOGRAPHIC_0@@
Combination with other products such as botulinum toxin, and a risk comparison
...
The truth about the risks, complications, and downtime you should know
...
Summary of this article: remember the "safe and beautiful choice" with four numbers
It was a long article, but what we want you to take home are these four numbers.
- 73.38%— hyaluronic acid is the overwhelming first choice, used in 73.38% of non-surgical approaches, and overall satisfaction is also extremely high at 94.94% (Williams 2020).
- 10 times— although the complication rate is very low at 1.63% overall, to prepare for a vascular disorder in the unlikely event, it is indispensable to choose a highly reversible product that can be quickly dissolved with hyaluronidase (calcium hydroxylapatite has about 10 times (Williams 2020) the complication risk of hyaluronic acid).
- 0.05 ml— the injection volume into the nose is small, even for the whole nasal dorsum at 1.0 ± 0.4 ml, requiring minute control of 0.05 ml to 0.1 ml (Trevidic 2022) per spot and accurate approach to the deep layer.
- less than 0.1 ml— even when combining other products such as botulinum toxin, keeping the injection volume to less than 0.1 ml (Gostimir 2023) per session greatly lowers the relative risk of adverse events.
Beauty stands only on a firm foundation of safety. Filler is not "something you put in" but "something you choose" — the type of product, firmness, volume, angle, depth. Only when all of these come together is the ideal result born for the first time. Please correctly understand the structure of your own face, and choose a trustworthy physician who provides the appropriate product and technique based on the latest data.
If you find yourself thinking, "What about my case?"
Book a free consultation
There is no pushy sales. Please feel free to get in touch.
Author of this article
Hiromitsu Nakamura Ginza Clinic Physician
Zetith Beauty Clinic Ginza, Osaka, and Fukuoka clinics
He has a track record of research presentations at domestic and international academic conferences, and is also engaged in technical guidance and education for Zetith Beauty Clinic as a whole. He specializes in precise aesthetic medicine based on anatomical grounds, pursuing natural results tailored to each person's bone structure and tissue.