Lip Filler Singapore — A Doctor's Guide

Lip filler or lip flip: what is the difference?

Lip filler adds material; a lip flip adds none. That single distinction decides which one fits.

Lip filler places hyaluronic acid gel in the lip body, border and Cupid's bow. It changes volume, shape and definition, and because it is gel it can be moulded at the time and dissolved later with hyaluronidase.

A lip flip is a small dose of botulinum toxin (BTX) placed into the orbicularis oris, the ring of muscle around the mouth. As the upper part of the muscle relaxes, a little more of the pink upper lip rolls outward, which is most noticeable when smiling. A 2025 systematic review describes it as a technique for subtle eversion without added volume, with transient effects such as difficulty using a straw or whistling.

The two answer different problems. A lip that is genuinely thin or has lost its border needs structure, which BTX cannot provide. An upper lip of reasonable volume that disappears on smiling may be better served by relaxation than by more product. Some plans use both, sequenced. Because the muscle around the mouth also speaks, eats and drinks, BTX here is dosed conservatively, and suitability is decided at assessment.

What can go wrong with lip filler, and how is it managed?

Most effects after lip filler are expected and short-lived: swelling, tenderness and bruising that settle over days. The less common problems are the reason the lip is treated in a medical setting.

Lumps can form when gel collects in one spot; many soften with moulding, and persistent ones can be dissolved. Migration — filler drifting above the border into the upper lip skin — tends to follow repeated volume over time or placement in the wrong plane, and is managed by dissolving and replanning rather than adding more. Cold sores can be triggered in people prone to them, which is why that history is asked about beforehand.

The serious complication is vascular occlusion, where filler compresses or enters a blood vessel. The lip has a rich arterial supply, so the signs — unusual pain, blanching or a dusky, mottled colour — are watched for during and after treatment. Hyaluronidase is kept on hand because it breaks down HA gel, and published guidelines set out how it is used urgently in this situation.

Restraint lowers risk as well as improving the look: smaller volumes, the right depth, and a review once swelling has resolved.

Who should not have lip filler?

Lip filler is deferred or avoided in some situations, and the consultation exists partly to find them.

Pregnancy and breastfeeding are reasons to wait. An active cold sore, infection or broken skin on or around the lips means postponing until it has healed. A history of non-resorbable filler in the lips, or filler of unknown type from elsewhere, needs careful assessment first, because injecting into or around it behaves differently.

Certain medical conditions and medications are reviewed, including autoimmune disease, bleeding tendencies and blood-thinning treatment, along with any previous reaction to filler or local anaesthetic. Recent or planned dental work matters too, since procedures in the mouth can introduce bacteria around fresh filler.

Expectations count as much as medical history. A request to match a filter or someone else's lips, or to keep adding volume to lips that are already in proportion, is a reason to pause rather than proceed. Lips are read against the chin, teeth and mid-face; where a recessed chin is making the lips look larger or smaller than they are, that is discussed before any lip plan is made.

Lip fillers in Singapore: what affects the cost?

The cost of lip filler follows the plan rather than a fixed figure, because the plan differs from one pair of lips to the next.

Four things shape it. First, the product: lip fillers differ in how firm or soft the gel is, and the choice depends on whether the aim is border definition, body volume or hydration. Second, the amount used, which follows the assessment of proportion rather than a preset volume. Third, whether existing filler has to be dissolved or corrected first — migrated or excess product is addressed before new work is added. Fourth, whether the plan is staged, with a conservative first treatment and a review once swelling has settled.

A figure quoted before anyone has looked at your lips cannot reflect any of these. Cost is set out clearly at consultation, before anything is agreed, and a decision not to treat — or to do less than was asked for — is always an acceptable outcome of that conversation.

How Dr Sin Yong approaches lip filler

Dr Sin Yong's lip approach, Rekindling the Lips, starts with proportion mapping rather than a volume. The lips are assessed against the whole lower face, including tooth show and chin projection, and where lips have thinned with age, old photographs are used so the plan returns structures that existed rather than imposing a new shape.

The sequence is border definition before body, support at the corners and philtrum, and projection rather than inflation. Hyaluronic acid filler is placed with fine needles at planned points along the border, body, Cupid's bow and corners, in small aliquots. He moulds the lip immediately after injection, reviews it with the patient and makes minor adjustments in the same session where needed; the settled shape is reviewed again once swelling has resolved.

Lip shapes and proportions: what a doctor looks at

Lips vary widely in shape, and much of that variation is normal anatomy rather than something to correct. Words such as full, thin, wide, heart-shaped, round, top-heavy or bottom-heavy are everyday ways of naming that variety; at assessment a doctor looks instead at the structures that create it.

The first is the ratio of upper to lower lip. Published measurements in several populations find the lower lip somewhat fuller than the upper, but the figures differ with ethnicity, age and sex, so the ratio is read as a reference point for one face, not a target. The second is the vermilion border, the edge where the pink lip meets the skin, together with the white roll just above it, which decides how defined the outline reads. The third is the Cupid's bow, the double curve at the centre of the upper lip, and the philtrum above it, the groove between the two philtral columns running up to the nose.

These are judged alongside the length of the upper lip, how much tooth shows at rest and when smiling, symmetry between the two sides, and the chin, teeth and mid-face around them. That is why two people asking for the same lip shape can need different plans, or none.