Onda Microwave
Where It Fits in Fat-Type Sagging and Double Chin

Three-Line Summary

• Onda uses 2.45GHz microwave energy (Coolwaves). Contact cooling holds the epidermis and dermis down in temperature while heat is designed to linger longer in the subcutaneous fat layer beneath them. The layer it mainly works in is simply different from that of ultrasound or radiofrequency.
• A double chin is a mix of fat-type, skin-type and skeletal-type patterns. Onda's share grows in the pattern where fat and laxity occur together. Where skin alone has loosened, or where jaw structure drives the appearance, Onda on its own can only carry so much.
• Change appears not immediately but gradually from two to three weeks onward, tending to be clearest around three months. A plan that holds a tolerable temperature for a sustained period influences the result more than one intense pass.

Where Onda's Microwave Energy Creates Heat

The core of Onda is microwave energy in the 2.45GHz band (Coolwaves). Devices get grouped together as "heat-based treatments," but when the physical route to heat differs, the layer where heat accumulates differs too. Understanding Onda starts with that route.

Dielectric heating — making heat by shaking molecules

Microwaves shake electrically polarized molecules such as water and fat billions of times per second, generating friction heat. This is called dielectric heating. It is physically distinct from the resistive heating of radiofrequency, where current runs between electrodes and tissue impedance produces the heat.

Radiofrequency often generates heat mainly in the dermis, where current flows readily. Microwave energy, by contrast, sets molecules moving at whatever depth the electromagnetic field reaches, so where you place the peak of that field determines which layer the heat concentrates in. Onda is a device built around that property.

Antenna design and contact cooling — two elements that only work together

Through the antenna structure inside the handpiece, Onda is designed so that the peak of the microwave field forms toward the subcutaneous fat layer rather than at the skin surface. On top of that, strong contact cooling deliberately limits the temperature rise in the epidermis and dermis.

Both have to run at once for this to mean anything. Antenna design alone would heat the surface as well; cooling alone would stop energy from reaching the deeper layer. Because the structure cools the outside while warming what lies beneath, it becomes possible to hold a state in which the epidermis and dermis stay relatively cool while heat accumulates and persists longer in the subcutaneous fat layer. Under reported device settings, the aim is to keep the skin surface around 30℃ while bringing the fat layer up toward roughly 50℃.

What "the same frequency as a microwave oven" actually means

Microwave ovens also use 2.45GHz microwaves, so you may well hear the worry: "isn't that putting a microwave oven on your face?" The frequency band is indeed the same, but the output and total energy are lower by an order that does not really compare, and the energy is delivered while the surface is cooled hard — which is a different situation altogether.

A microwave oven is meant to heat food evenly throughout. Onda is meant to hold a limited amount of energy in one particular layer. The same physics applies, but the conditions of use are close to opposite. Leave that difference out and "the same principle as a microwave oven" invites misunderstanding.

How the treatment feels

Because of that design, the sensation during treatment has a different character from other devices. Many people describe it as "cool on the surface but warm underneath," "like a warm stone pressing down," or "like a hot compress." That is close to the normal response while surface cooling is working and the fat layer is coming up to temperature.

Clinical studies report pain scores averaging around 2 to 3 out of 10. It is unlike the resonance against bone that ultrasound can produce, and unlike a sudden hot spot at the surface. Because the heat rises gradually, treatment often proceeds without numbing cream. That said, if too much energy is delivered, warm can tip over into hot, so what you tell us during treatment becomes the reference point for adjusting intensity.

Low pain is an advantage, but it does not by itself indicate the size of the effect. Pain is low because there is little stimulation at the surface, not because the energy is weak. Conversely, keeping intensity low just because it does not hurt can leave the fat layer too cool for the intended response. Not placing pain and result on the same axis is the first step to understanding Onda.

Ultrasound, Radiofrequency and Microwave Are Not the Same Heat

Lifting consultations often line up device names side by side, but what actually separates them is which layer the response is created in. Different layer, different problems handled well.

The fat layer is not the layer ultrasound and radiofrequency mainly handle

Ulthera forms micro-coagulation points in deep support structures including the SMAS, prompting the tissue to reorganize. Density warms the dermis broadly to drive collagen remodeling. Neither device is built with fat volume reduction as its goal. In fact, with radiofrequency aimed at the dermis, excess heat carried down into the fat layer can produce unwanted hollowing of the cheeks, so settings are adjusted to avoid it.

Onda turns that same phenomenon around. What a dermis-targeting device has to avoid becomes the objective for a device targeting the fat layer. This is why the same double chin is approached differently depending on the device.

Onda is not a device that pulls upward — it is one that tidies

Onda is often introduced as a lifting device, but judged by the layer it acts on, it sits closer to contouring than to lifting. Lifting means pulling descended tissue upward and supporting it. Contouring means easing excess volume so the line reads more clearly.

That said, Onda does not deal with volume alone. The fibrous septae (connective tissue) running through the fat layer respond as well, adding a sense of tightening, and some heat reaches the dermis, so a collagen response tends to follow. What people actually notice is therefore closer to a little volume eased and, at the same time, a slight tightening. Rather than thinking of it as removing fat, it is closer to the reality to understand it as easing the weight that was pulling the tissue down, through the response of fat and connective tissue.

The Fat Layer Responds to Temperature × Time

What determines the outcome with Onda is not whether a clinic owns the device but at what temperature the fat layer was held, and for how long. If that condition is not met, a long treatment session still may not produce the intended response.

A tolerable temperature held steadily, rather than short and hard

Fat cells exposed above a certain temperature for a certain length of time are understood to sustain membrane damage and enter a process of self-clearance (apoptosis). The key point is that temperature and time have to be met together. Spiking very hot for a moment and cooling straight back down may not fill the condition.

So in practice we do not start excessively low. We bring the temperature up relatively quickly toward the target, then ease back to a point just below the line where it reads as "hot" and hold there. From the patient's side that is warm but bearable; from the operator's side it is the band where a response can be expected within a safe range.

Why the same total energy can give different results

In Korea, Onda is often explained in terms of total energy in joules (J). But even at the same total energy, how that energy is spread out changes the conditions the tissue experiences.

• Hard and fast — the session is shorter and the immediate sense of tightening can be strong, but momentary pain is greater, and if temperature spikes and drops quickly the hold time may fall short. The burden of responses such as erythema is also relatively greater.
• Moderate intensity, held steadily — it takes longer to reach the target temperature, but once there the band is easier to maintain for a set period. There is also more room to adjust while watching the response during treatment. The trade-off is a longer session.

At ABLE Dermatology we work by default from bringing the temperature near target early, then holding it evenly at a tolerable intensity. Rather than spending the total quickly, what connects more closely to the result is the temperature band that same total was held in, and for how long.

Why a sauna or a heat room is not a substitute

"Couldn't I just sit somewhere hot for a while?" is another frequent question. A sauna or heat room warms from the skin surface inward by convection and conduction, so surface temperature rises while the temperature of the subcutaneous fat layer most likely barely changes. The whole body warms evenly; energy does not gather in any one layer.

Onda does the opposite: it cools the surface while concentrating energy at a specific depth. The sensation of a cool surface over warmth beneath comes from exactly that difference. Everyday heat exposure and the selective heating of a medical device are hard to group together.

We define the areas that must not shrink first

Acting on the fat layer also means that a poorly planned treatment can affect volume in areas that should keep it. That includes areas already hollow, areas where fat is thin, and areas where further volume loss would make the face read as older.

So before treatment we set the field to be treated along with the field to be excluded. We plan the path so energy does not stack and overlap, and we allocate intensity and time differently by area. Skip this and you can end up with the area under the chin tidied while the cheeks look hollowed alongside it.

Fat-Type, Skin-Type and Skeletal-Type Double Chin, and Where Onda Sits

The reason "double chin means Onda" falls apart is that the same double chin can be built differently underneath. Differentiating by cause is covered in detail in our column on the causes and types of double chin; here we organize it by how much of each type Onda can take on.

Fat-type — the pattern where Onda's share is largest

Here subcutaneous fat has genuinely built up thickly under the chin and in the lateral cheek. Even without high body weight, the jawline and neckline do not run smoothly into each other, and the face commonly reads as one mass in photographs. On palpation there is a soft thickness to hold, and tilting the head back tends to reduce the fullness noticeably.

In this pattern, pulling the support structures up alone often leaves satisfaction low because the weight of the fat stays exactly where it was. The layer Onda handles is the layer where the problem lives, which is why Onda's share is largest in this type.

Skin-type — the pattern where Onda alone carries less

Here fat is not abundant, but the skin and the support structures beneath it have loosened, blurring the jawline. On palpation the thickness you can hold is thin, and lightly pushing the skin upward brings the line back — a characteristic sign. As collagen and elastic fibers decline with age and the SMAS loosens as well, this pattern becomes more distinct.

In this case, putting energy only into the fat layer means there is not much fat to reduce, so the change is small, and the remaining volume can be reduced further, leaving the face looking hollow. It is natural for ultrasound working on support structures, or radiofrequency working on the dermis, to take the larger share.

Skeletal-type — a question that sits before device choice

Here the lower jaw does not project far enough forward, or chin length and neck length are themselves short, so the space under the chin is narrow in profile. Even without much fat, a profile photograph shows no clear boundary between jawline and neckline.

This pattern is not a problem solved by working on the fat layer or the support structures. Repeating Onda may not produce the change hoped for, and it is more accurate to reset the goal itself or to discuss approaches at a different level alongside it. It is also the type that needs to be identified first in consultation.

In practice, most cases are mixed

The double chins we see in clinic rarely fall cleanly into one of the three types. Far more often they are mixed — fat plus laxity, or laxity plus skeletal structure. The purpose of differentiating is therefore not to attach a label but to work out which layer holds the largest share, and to set the sequence from there.

One more thing to check. If the fullness under the chin is firm toward the back on both sides rather than in the middle, it may involve the salivary glands rather than fat. An approach aimed at the fat layer tends not to produce much change in that case, so palpation and any necessary assessment should come before a treatment is decided.

Tips and Treatment Areas — Where It Is Used, and Where It Is Not

Onda is a device used by combining tips of different depth and treatment area. The same energy behaves differently depending on which tip handles which region.

Different tips for narrow areas and broad areas

• Pocket tip — a small treatment area, used for narrow regions where the line needs to be worked in detail, such as around the jawline, under the chin and the front of the neck.
• Shallow tip — a broader area, used for regions with some surface where fat and laxity occur together, such as the deep cheek, submental fat and below the jawline.

The Onda configurations available in Korea generally carry out facial and submental contouring with these two tips. Separate tips aimed at deep fat in the abdomen or thighs are intended for body use and differ from the configuration used on the face.

Areas where Onda is not used

Device manuals and international recommendations consistently specify areas where use is contraindicated.

• Scalp and head — not used over the region directly above the skull.
• The area around the heart — excluded from treatment.

Conversely, the facial regions clearly given as indications are the lower face: the jawline, under the chin and the front of the neck. Rather than treating the whole face broadly, the baseline is to confine use to the lower face, where fat is actually creating the problem.

Areas where fat is thin are not Onda's target

In regions such as the forehead, the temples and above the cheekbones, where there is little soft tissue and bone shows through, the very layer Onda targets is thin. These regions are not its main target, and where something is needed there, we approach from devices that work in a different layer. That is why "Onda over the whole face" does not follow naturally.

How a session runs

The session itself follows a fairly simple flow. After cleansing, the treatment field and the excluded field are marked; a dedicated gel is spread broadly so the microwave energy is delivered evenly; then the handpiece is moved at a steady speed while energy is delivered. Because hand speed and degree of overlap are what set temperature and hold time, the speed of the hand contributes to the result as much as the output figure on the device.

During treatment, skin temperature and response are checked and intensity adjusted; afterward there is a soothing step. As there is no incision or injection, a separate recovery period is generally not set aside, and warmth or mild swelling usually settles within a short time. The degree of response does vary from person to person.

The Timeline of Change, and How Long It Holds

Disappointment with Onda usually comes from starting without knowing when what becomes visible. Knowing the timeline in advance matters a great deal to satisfaction.

Immediate tightening and later change are two different things

Straight after treatment many people do feel the face looks a little tidier. But this is closer to temporary tightening from heat than to reduced volume. Once fat cell membranes are damaged, the process in which surrounding immune cells gather and clear the damaged cells generally begins over two to three weeks.

It is therefore better not to judge from how things look on the day. The change Onda is aiming at is the kind that emerges over time.

Around three months, and how long it lasts

• 2 to 3 weeks — when the process of clearing damaged fat cells begins
• Around 3 months — reported as the point at which change is felt most clearly
• 6 to 9 months — where weight is held within about plus or minus 3kg, results have been reported to last roughly this long

This timeline is an average course; there is individual variation with fat thickness, skin firmness, age and daily habits. And while damaged fat cells themselves do not recover, volume can return if the remaining fat cells enlarge again with weight gain. That is why weight management is mentioned alongside maintaining the result.

How the number of sessions is set

One session can give a sense of reduced puffiness or a slightly tidier look, but if the goal is a change in the contour itself, it is more realistic to plan three sessions at two to four week intervals and then adjust the final count between three and six while watching the response.

It also helps to be clear that what Onda reduces is volume and thickness in a localized area, not the number on the scale. Changing body weight itself belongs to diet and exercise, and Onda does not replace that. Keeping the two separate helps set expectations against reality.

What to pay attention to afterward

Onda is not a treatment with long downtime, but because the result unfolds over weeks to months, how you look after yourself in that period plays a part.

• Day of treatment — warmth may remain in the area, and cooling it to settle is fine. It is better to avoid high-temperature environments such as saunas and heat rooms, and exercise that provokes heavy sweating, for a few days.
• First week — it is safer to pause strongly active skincare ingredients for a while. Washing the face and wearing makeup are usually possible as normal.
• Afterward — consistent sun protection, and keeping weight from rising sharply, both affect how the result holds.

This guidance is a general baseline and can change with skin condition and treatment field. Individual guidance is given directly after your treatment.

It is not a one-and-done treatment

The effect can hold for several months or longer, but aging, gravity and daily habits carry on. People who were satisfied with the result have generally planned maintenance sessions at set intervals. The timing and interval of maintenance are also worth settling together before the first treatment.

Questions About Microwave Safety

This comes up often in Onda consultations. "I heard microwaves are bad for the brain" and "is there any risk of hippocampal damage?" are the typical versions. Here is what is known.

Animal study conditions and aesthetic device conditions are different

Some animal studies have reported hippocampal neuronal damage and reduced memory in rats when strong microwave energy was applied to the head or whole body over long periods. Those conditions, however, exposed brain tissue directly beneath the skull and deliberately used intensities and durations beyond human safety limits.

That is a different set of conditions from an aesthetic device using limited energy on skin and fat and not treating the scalp or head at all. The same word appearing in both places does not make them the same situation.

What has been reported so far, and what is still missing

Clinical studies published to date on Onda and similar aesthetic microwave devices include numerous reports of improvement in double chin, localized fat and skin laxity, while no adverse events directly linked to hippocampal damage or reduced cognitive function have been identified.

To put it honestly at the same time, long-term studies following thousands of people over several years are still not sufficient. Having no grounds in current data to declare a risk is a different statement from long-term safety having been fully established.

So we keep our principles of use conservative

For these reasons, ABLE Dermatology confines Onda to the lower face: the jawline, under the chin and the front of the neck, and works in a direction that avoids unnecessarily wide fields, excessive energy and excessive session counts. The scalp, the head and the area of the heart are excluded from treatment.

The principle of using only where needed and only as much as needed is not because a risk has been confirmed, but because there is no particular reason to use more in territory that has not been mapped. Safety questions are welcome in consultation before treatment.

How ABLE Dermatology Runs Onda

ABLE Dermatology has Onda (ONDA, DEKA — Coolwaves 2.45GHz microwave), and in the same lifting space keeps Ulthera Prime (focused ultrasound), Density (sequential radiofrequency) and Olewave (focused shockwave) alongside it. More important than owning several devices is that the share each one takes is divided according to which layer holds the largest part of the problem.

The ABLE Double Chin Package

This is our signature program, built for cases where fat and laxity occur together under the chin. Within a single session it runs Onda on the subcutaneous fat layer first, then Ulthera on the SMAS layer, finishing with a step that refines the detail in the remaining areas.

There is a reason for that order. Address volume alone and the laxity in that spot can become more noticeable; pull the support structures alone and the weight of the fat stays exactly where it was. The point of this combination is handling volume and support in sequence within the same session. Details of the program are available in the double chin package guide.

When it runs alone, and when it is combined

• Raising Onda's share — when fat thickness under the chin and in the lateral cheek is clear and baseline firmness has not dropped much
• Combining with ultrasound or radiofrequency — when fat and laxity occur together, or when support structures have already been addressed by other treatment and localized fat remains
• Lowering Onda's share — when fat is thin and skin laxity is the main problem, or when hollowing has already progressed and volume should not be reduced further

The same double chin is approached differently depending on which of these three it belongs to. The Onda treatment guide covers the device itself in more detail.

We also tell you when we would not recommend it

Repeating Onda where fat thickness is not sufficient can mean little of the hoped-for change and only a loss of volume. The same applies where jaw structure is the major factor — that is not a problem in the layer Onda works in. In these cases we either do not recommend Onda, or reset the goal and discuss approaches at a different level.

Owning a device and that device being right for the face in front of us are two different statements. What consultation has to establish is not a device name but where the largest share of your own submental fullness actually lies.

From Consultation Through Treatment

A board-certified dermatologist examines you directly to identify the layer behind the problem, sets the device and parameters, and then the same dermatologist carries out the treatment. There is no structure in which a consultant recommends the procedure.

Session count, intervals, maintenance timing and cost are all settled together before the first treatment.