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Trap of a hard hyaluronic acid preparation that is said to have a long-lasting effect




Hidemasa Shinohara
Dr. Hidemasa Shinohara

Skin Refine Clinic Ginza

Regular member of the Japanese Society of Plastic Surgery Certified specialist Regular member of the Japanese Society of Clinical Dermatology Regular member of the Japanese Society of Cranial Forehead Surgery

Medical institution with Dr. Hidekatsu Shinohara

skin refine clinic skin refine clinic ginza
Contact: 0120-661-062

There are various types of hyaluronic acid preparations used in aesthetic medicine by multiple manufacturers.

There are differences in properties such as the ability to lift skin tissue, elasticity, and cohesiveness, and they are used according to the injection site and treatment purpose.

In general, hyaluronic acid preparations, which have hardness, are used for procedures such as lifting cheeks, making the nose look higher, and injecting into the tip of the chin to make the face line look sharper, and the injection effect tends to last longer.

Hard hyaluronic acid is a hyaluronic acid preparation that has many advantages considering its forming power and persistence, but there are also unfavorable treatment sites and risks.

Organizing the differences in the applicable areas due to differences in the hardness of hyaluronic acid preparations, and knowing that the finish differs depending on the type of hyaluronic acid preparation and the technique of the practitioner, is a great way to practice without regrets. important to receive.

Trap of a hard hyaluronic acid preparation that is said to have a long-lasting effect

Features of hyaluronic acid preparations that differ by manufacturer

Hyaluronic acid preparations used in aesthetic medicine vary in molecular weight (particle size), concentration, and content of ingredients, depending on the unique manufacturing method of each manufacturer .

This makes a difference in the following properties:

Differences between products of hyaluronic acid preparations


Viscoelasticity is stickiness and the ability to return to its original shape after being stretched like rubber, and expresses the ease of deformation. It gradually deforms when a force is applied, and returns to its original state when the applied force is reduced.

tissue affinity

When it has an affinity with skin tissue, hyaluronic acid adapts to the movement of the skin caused by changes in facial expressions, giving it a natural finish.


Cohesiveness is the property of hyaluronic acid to remain at the injection site. If it has excellent cohesiveness, it will retain its shape even if force is applied from the outside.

formative force

Forming force is the force that shapes things. The forming power of hyaluronic acid is necessary for procedures such as sharp face lines and narrowing the nose bridge.


Sustainability refers to the ability to maintain the injection effect. In general, the duration of hyaluronic acid preparations is said to be about six months to one year, but it varies depending on the hyaluronic acid preparation.

water absorption

Water absorption is the ease with which water is absorbed, and if the water absorption of hyaluronic acid preparations is low, the possibility of swelling due to water in the body after injection is low, reducing the risk of a different image after injection.

Difference by series

Most hyaluronic acid preparations have several series in their products.

For each series, the concentration of hyaluronic acid, the size of the particles, and the concentration of the cross-linking agent are changed, which makes a difference in the hardness of the hyaluronic acid. Due to the difference in hardness, it can be used for minor wrinkles and lips such as fine wrinkles around the eyes, for lifting moderate sagging such as nasolabial folds, and for contouring specific parts such as nose and chin . The contents of the treatment will change.

Therefore, even with the same product, there are multiple series, so the finish will be different.

In addition, most hyaluronic acid preparations contain lidocaine, which relieves pain, but there are also products that do not contain lidocaine.

Some people are allergic to lidocaine, so in that case, it is safe to choose a hyaluronic acid preparation that does not contain lidocaine.

Molecular weight of hyaluronic acid and cross-linking agents that affect the hardness of hyaluronic acid

Molecular weight of hyaluronic acid

Hyaluronic acid includes hyaluronic acid found in the human body, shark fin, chicken wings, skin, comb, and soft-shelled turtle, as well as artificial hyaluronic acid used in cosmetic medicine. .

Hyaluronic acid in the natural world is a high-molecular hyaluronic acid with a large molecular weight of hyaluronic acid , and artificially produced hyaluronic acid is a low-molecular-weight hyaluronic acid with a small molecular weight .

Hyaluronic acid is like a chain in which a number of molecules of glucuronic acid, a type of acid, and N-acetylglucosamine, a type of sugar, are alternately linked. High-molecular-weight hyaluronic acid has many chains that are naturally connected, but low-molecular-weight hyaluronic acid has a short chain structure.

The lower the molecular weight of hyaluronic acid, the easier it is to be decomposed and absorbed by the enzymes present in the body .

Therefore, some manufacturers have developed their own production methods to keep the molecular weight of hyaluronic acid as high as possible.

Cross-linking agents added to hyaluronic acid formulations

Hyaluronic acid preparations used in cosmetic medicine are often added with a cross-linking agent that acts like an adhesive that connects the chains of hyaluronic acid .

The presence of a cross-linking agent that bridges the gap between hyaluronic acid molecules links the molecules and processes them into a viscous solid (gel-like), slowing the speed at which it is absorbed into the body. It is prepared as

Advantages and disadvantages of hyaluronic acid preparations with hardness due to cross-linking agents

Advantages of hard hyaluronic acid preparations

Artificially produced hyaluronic acid cannot remain in the body as it is for a long time after injection.

Therefore, cross-linking agents are added to most hyaluronic acid formulations. 1,4-butanediol diglycidyl ether (BDDE) is used as a cross-linking agent in many hyaluronic acid formulations.

The higher the proportion of cross-linking agent (BDDE) included, the stronger the action of binding hyaluronic acid molecules, and the longer the injection effect .

In addition, since the feel is hard and the shaping power is increased, it can be expected that the shape will be maintained even in treatments such as making the nose bridge look neat and sharpening the chin to create an E-line that connects the nose and chin.

The consistency of hyaluronic acid formulations makes them less likely to spread to unwanted areas within the skin tissue after injection.

Disadvantages of hard hyaluronic acid preparations

Hyaluronic acid preparations, which have a high degree of hardness due to the high proportion of cross-linking agents, are good at contouring, but are not suitable for forming procedures such as eye bags and lip volume-up, which require a soft finish in areas where the skin is thin. .

By adding a cross-linking agent to the hyaluronic acid formulation, the shape will be maintained for a long time, but it is said that if there is too much cross-linking agent, lumps and unevenness will easily occur at the injection site . It can be highly palpable, like rumbling to the touch .

When the surrounding tissue moves or an external force is applied, if the ability to flexibly expand and contract and restore the shape is low, facial expressions may look unnatural .

Hard hyaluronic acid risks

Cross-linking agents are said to have the risk of causing redness and inflammation, and in order to reduce the risk, it is important to choose a hyaluronic acid preparation with the lowest possible cross-linking agent content .

Kaisense, a hyaluronic acid preparation that overturns conventional wisdom

Hyaluronic acid injection has been increasing in the number of treatments since the late 1990s in aesthetic medicine, but new products are being developed and released one after another in order to reproduce the desired injection effect and maintain greater safety.

KYSENSE, which was launched in the EU in February 2021, is one of them.

Hyaluronic acid injection therapy is a cosmetic treatment that is selected as one of the ways to improve sagging by those in their late 30s and beyond who are beginning to worry about changes due to aging and want to look younger. You tend to take it repeatedly to get results. In addition, it is a procedure that is often revisited in hopes of injecting into a different site than the first.

The most important thing required at that time is a beautiful and natural finish.

Kaisense is a hyaluronic acid formulation with excellent forming and lifting power, and is said to have high performance to provide natural beauty and higher safety .

Features of Kaisense

Generally speaking, the harder the hyaluronic acid formulation, the better its forming power and lasting power. A new product that overturns common sense .

You can expect a natural finish because of its suppleness and flexibility that matches the movement of facial tissues when creating expressions.

In addition, it is said that the most important characteristic of Kaisense is its ability to lift the skin tissue, which is a high lifting force, and even a small amount can achieve a high lifting force .

Kaisense is able to achieve such high performance thanks to a patented manufacturing method for hyaluronic acid preparations.

Kaisense's patented manufacturing method

Kaisense is a hyaluronic acid formulation made by the patented OXIFREE manufacturing method.

During the manufacturing process of hyaluronic acid formulations, active oxygen is generated that destroys the molecular structure of high-molecular-weight hyaluronic acid. Artificially produced hyaluronic acid has a molecular structure of low-molecular-weight hyaluronic acid due to active oxygen, so the time it stays in the body after injection is short, and the volume formed by injection tends to be less durable.

However, Kaisense's OXIFREE manufacturing method is said to be able to maintain the long chain of high-molecular-weight hyaluronic acid by thoroughly removing active oxygen generated during the manufacturing process .

Kaisense is a hyaluronic acid formulation with reduced risk

Since hyaluronic acid has higher viscoelasticity as the molecular weight of the polymer increases, even a small amount of Kaisense tends to have high lifting power and forming power .

Since we have succeeded in maintaining the chain of high-molecular hyaluronic acid, there is no need to add a large amount of cross-linking agent, making it possible to keep the amount of cross-linking agent to a minimum .

Hyaluronic acid preparations have the risk of redness and inflammation due to cross-linking agents, so Kaisense, which has less cross-linking agents, has less risk of complications than other hyaluronic acid preparations.

What it takes to get a high level of satisfaction

In hyaluronic acid injection therapy, it is necessary to select a suitable hyaluronic acid formulation to achieve each purpose, such as ``I want to make wrinkles less noticeable'', ``I want to improve sagging'', and ``I want to make contours look neater''.

However, even if the same hyaluronic acid preparation is used, it does not mean that the result will be the same even if the practitioner changes.

There are multiple layers to inject hyaluronic acid, such as intradermal, subcutaneous, and periosteal layers, and there are various injection methods, such as pinpoint injection and fan-shaped injection. It is also necessary to use a sharp needle called a needle and a blunt needle called a cannula depending on the injection site and injection method.

In order to obtain a high degree of satisfaction, it is necessary to select a high-performance hyaluronic acid preparation and have high injection skills . It is important to choose a doctor who has a good knowledge of anatomy and who is constantly brushing up on new injection techniques and has a lot of practical experience.

Medical institution with Dr. Hidekatsu Shinohara

skin refine clinic skin refine clinic ginza
Contact: 0120-661-062