Filler is not the only way to address a hip dip or flat buttock. Depending on frame and the change wanted, autologous fat grafting, an implant, or BiVol hip-up — fat-centred surgery using acellular dermis and hyaluronic acid together — can be compared. The first step is not making the buttock larger but identifying which is deficient: upper volume, posterior projection, or the hip dip.
Contents
How do a hip dip and a flat buttock differ?
Both look like a lack of volume, but the missing volume sits in different places. A hip dip is a lateral line that curves inward between the pelvis and thigh; a flat buttock usually lacks upper or central posterior projection when seen from the side.
So rather than enlarging the whole buttock the same way, the question is where volume should be added for the waist, pelvis and buttock line to connect naturally.
How does BiVol hip-up work?
BiVol hip-up designs volume for the buttock and pelvic line around autologous fat, used together with acellular dermis and hyaluronic acid. Fat is distributed to the areas that need it, so the result is not just a larger centre but adjusted upper volume, posterior projection and lateral hip dip according to the frame.
What matters is therefore where and in which layer a given amount is placed, not simply how much goes in.
Read alsoThe basic concept of BiVol hip-up is covered in “Implant-free BiVol hip-up for a better silhouette” (Korean).
How does BiVol differ from buttock filler?
| Aspect | Buttock filler | BiVol hip-up |
|---|---|---|
| Main material | Hyaluronic acid and similar fillers | Fat plus acellular dermis and hyaluronic acid |
| Method | Injection into the desired area | Fat harvest, then regional grafting and supplementation |
| Character | Comparatively simple procedure | Volume designed across several regions |
| Considerations | Migration, nodules, infection | Swelling, asymmetry, differences in fat take |
Concern about filler side effects does not make BiVol a safer method by definition: filler and fat-based surgery differ in the kinds of complications and the recovery involved, so the question is which suits your frame and the change you want rather than which is safer in the abstract.
In a systematic review of 10 studies (168 patients) using HA filler for gluteal volume, mean effect duration was about 16 months, with some reports of injection-site inflammation and filler migration.[1]
When is BiVol considered?
Where a hip dip and upper buttock volume need addressing together, or where a route other than filler or a silicone implant is wanted, BiVol can be compared as one option:
- Hip dip and upper buttock volume both deficient
- Uncomfortable with enlarging only the centre
- Wanting the waist-to-pelvis-to-buttock line considered together
- Looking for an alternative to filler or a silicone implant
Because fat is part of the method, how much fat can be harvested from the abdomen or thigh must be confirmed.
In a one-year prospective study of HA buttock filler, satisfaction fell from 90% at 30 days to 62% at 12 months.[2]
BiVol hip-up: common myths and facts
| You may think… | In practice |
|---|---|
| "One filler session lasts for years." | Mean duration in studies was about 16 months. |
| "Filler has almost no side effects." | Injection-site inflammation and migration have been reported. |
| "BiVol is a kind of filler." | BiVol is a surgical method using ADM, not a filler. |
When comparing hip filler and BiVol I split it by how long and how much. To try a small change first, filler; where duration matters more, a surgical approach is reviewed.
A hip dip and a flat buttock lack volume in different places, so the first question is where, not how much. BiVol hip-up designs volume around autologous fat with acellular dermis and hyaluronic acid, so upper volume, projection and the lateral dip can be adjusted to the frame rather than enlarging only the centre. Filler's limits show in the numbers: a 10-study review of 168 patients found mean duration around 16 months with reports of inflammation and migration, and a one-year prospective study saw satisfaction fall from 90% at 30 days to 62% at 12 months. Neither is safer by definition — the complications simply differ.
🔬 The research behind this article
These are the international journal papers that support the content above. Select a title to open the abstract on PubMed.
- Aesthetic Plastic Surgery 2023 — systematic review of 10 studies, 168 patients, HA gluteal fillerMortada H, Alkadi D, Saqr H, et al. Effectiveness and Role of Using Hyaluronic Acid Injections for Gluteal Augmentation: A Comprehensive Systematic Review of Techniques and Outcomes. Aesthetic Plast Surg. 2023;47(6):2719-2733.Key: mean duration about 16 monthsText [1] · PMID 37407710 · DOI
- Journal of Cosmetic Dermatology 2025 — one-year prospective study of HA gluteal fillerBussade M, Faria G, Barros M, et al. Assessment of Hyaluronic Acid Filler in Gluteal Augmentation and Contouring: A 1-Year Prospective Study. J Cosmet Dermatol. 2025;24(12):e70600.Key: satisfaction 90% at 30 days, 62% at 12 monthsText [2] · PMID 41423732 · DOI
🎬 Watch: Dr. Park Seong-Soo on video
Korean-language videos from BongBong Plastic Surgery's official channel and Dr. Park's channel, “Seongsu-ro Doctor”. Titles are translated for reference; selecting one opens YouTube.
- Can you have an apple hip with a hip dip? BiVol hip-up without an implantSeongsu-ro Doctor · 2026.08.26
- How to fill a slim hip: hip dip volume and firmness with BiVolSeongsu-ro Doctor · 2025.12.22
Frequently asked questions
Is BiVol the same as buttock filler?
A. No. Buttock filler injects a filling agent directly, while BiVol designs volume with autologous fat plus other materials.
Can a hip dip alone be treated with BiVol?
A. Treatment can centre on the lateral deficiency, though the actual scope depends on pelvic shape and existing fat volume.
Is it possible in a slim person?
A. Feasibility depends on how much fat can actually be harvested and the volume wanted, more than on body weight.
Is BiVol safer than filler?
A. They cannot be ranked as a blanket statement. Filler and fat-based surgery differ in materials and complication patterns, so each method's risks should be reviewed separately.
📖 References
Select a [number] in the text to jump to the source, and ↩ to return. Only papers whose title, journal and year were verified on PubMed are included.
- Mortada H, Alkadi D, Saqr H, et al. Effectiveness and Role of Using Hyaluronic Acid Injections for Gluteal Augmentation: A Comprehensive Systematic Review of Techniques and Outcomes. Aesthetic Plast Surg. 2023;47(6):2719-2733. — Aesthetic Plastic Surgery 2023 — systematic review of 10 studies, 168 patients, HA gluteal filler. ↩
- Bussade M, Faria G, Barros M, et al. Assessment of Hyaluronic Acid Filler in Gluteal Augmentation and Contouring: A 1-Year Prospective Study. J Cosmet Dermatol. 2025;24(12):e70600. — Journal of Cosmetic Dermatology 2025 — one-year prospective study of HA gluteal filler. ↩
BongBong Plastic Surgery · Dr. Park Seong-Soo, Medical Director
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