The face deflates before it sags.

They answer different questions. A firm hyaluronic gel restores a temple or a cheekbone on the day, is judged at two weeks, lasts a year or two and dissolves with an enzyme if the face was misjudged — the right first treatment, and the one the temple and midface trials were built on. Poly-L-lactic acid does nothing on the day and builds over three months into the patient's own collagen, across the whole face rather than one shelf; in the randomised comparison it beat hyaluronic acid 90.6% to 51.0% at twelve months, at the price of a 10% nodule rate and no reversal. Learn your face on the gel; graduate to the stimulator when you know how much volume you actually want, because that decision cannot be undone.

The pivotal trial treated 112 people with no serious adverse events and the approval followed, so the answer in expert hands is yes. The anatomy is the reason for the caveat: the superficial temporal and zygomatico-orbital arteries connect to the eye, the middle temporal vein to the lungs, and the published catastrophes — blindness, embolism — came from gel in those vessels. The safeguards are specific: injection deep on the periosteum or in the plane between the superficial and deep temporal fasciae that the meta-analysis supports, a cannula rather than a needle, aspiration, small volumes, slow injection, and hyaluronidase within reach. A temple should not be a first-year injector's site; ask how many they treat a month, and ask to see the emergency kit.

The trials give the visible durations: temple hyaluronic gel held its response in 73% at 13 months and the newer product reports results toward 18; midface gel had 79% of patients still rating their cheeks improved at two years; poly-L-lactic acid held 97% of temples at twelve months and its class reaches two years and beyond; fat grafting is permanent for the fraction that survives and then follows body weight. The number that matters more is the invisible one: MRI finds hyaluronic gel persisting in the midface for years after the effect has faded, expanding rather than shrinking, which is why a routine yearly top-up accumulates. The second session is decided by comparing the three-quarter photograph, not by the anniversary.

Fat is the patient's own tissue, ages with the face, follows body weight and is permanent for what survives; the trades are an operation with a donor site, survival that averages 47% and varies from a quarter to four-fifths so a second session is common, no reversal, and the rare catastrophe of fat in an artery, which nothing dissolves. Filler is an afternoon, judged at two weeks, reversible, and trialled site by site with responder rates of 80–89%; its trades are a year or two of visible effect and gel that lingers invisibly. The usual sequence is filler until the face has told you how much volume it wants, then fat — or a collagen stimulator — for the person who is done with syringes; and fat at the same operation for anyone having a lift anyway.

The medicines empty deep facial fat fast and, in an older face, the skin does not follow; the temples and cheeks go first, and the clinics treating these patients describe a layered plan — hyaluronic gel on the shelves of the cheekbone and temple, poly-L-lactic acid for the deflation across the face, and skin quality work over it — with an open-label study of the combination reporting improved harmony. The timing rules matter more than the products: hold the weight for a few months before anyone injects, because a face refilled during the loss is refilled again after it; do the recline test, because a face that is now also loose needs support and tightening rather than more volume; and keep the volume modest, because the skin has already been stretched once. The sagging-skin guide covers the laxity half.

Estrogen shapes where a woman's body stores fat, including the cheeks and lips, and its withdrawal at menopause is one reason the face deflates in the fifties. Menopausal hormone therapy has a meta-analysis for skin elasticity, thickness and collagen, graded in the sagging-skin guide, and it is prescribed for menopause rather than for looks; nobody has shown it refilling the temples or the cheeks, and the fat that left is replaced with the treatments on this page. A woman whose face changed fast around menopause has two conversations to have — one with a menopause clinician about hormones and her skin, one with an injector about volume — and they are not the same conversation.

The overfilled face is made by four habits: filling descent as if it were deflation, building a cheekbone that was never there instead of restoring the medial cheek that was, topping up on an annual schedule while gel from previous years persists, and never dissolving. The defences are the opposites. Lie flat before every course — if the face improves lying down, it wants support and repositioning, not volume. Restore the medial cheek and the temple, which read as youth, before the lateral cheekbone, which reads as a procedure. Compare the three-quarter photograph before each session and skip the ones you do not need. Know the total millilitres in your face. And choose a clinician who proposes hyaluronidase as easily as a syringe, because the same enzyme that reverses an occlusion reverses a mistake.

Hyaluronic gel shows on the day and is judged at two weeks once the swelling has gone — the moment a misjudged temple can still be dissolved. Calcium hydroxylapatite fills on the day and firms over months as collagen forms around it. Poly-L-lactic acid is the patient's exercise in trust: the water it is suspended in is absorbed within days and the face returns to baseline, then collagen builds over six to twelve weeks, sessions are spaced a month apart and the course is judged at three months after the last. Fat grafting is over-corrected on the day, swollen for weeks, and the fat that will survive has declared itself by three months, with the final result at six. Photograph at three-quarters in daylight before anything.

The ladder in euros: the recline test and a three-quarter photograph (free, the whole diagnosis) → weight settled and lost slowly, half an hour of facial exercise if you will do it, a retinoid and sunscreen (€10–30 a month, the skin over the hollow) → hyaluronic gel for the temple (€400–800) and the medial cheek (€600–1,600), reversible, a year or two → calcium hydroxylapatite for a firmer cheek (€800–2,100) → a poly-L-lactic acid course for the whole face (€1,000–3,200, two years) → fat grafting (€3,500–8,000, once or twice, permanent for what survives) → a facelift with fat grafting when the face is descended too (€10,000–22,000). Skin boosters, "volumising" creams and energy devices sit outside the ladder for this problem, and the last of them sometimes causes it.

The temple is the most dangerous injection site on the face because it is crossed by vessels going somewhere worse. The superficial temporal artery and the zygomatico-orbital artery connect through the orbit to the ophthalmic circulation, so gel forced into either can reach the retina; the middle temporal vein, running in the temporal fat pad between the two layers of the deep temporal fascia, drains through the superficial temporal vein to the external jugular, and gel injected into it has caused pulmonary embolism (venous danger zone review; CT angiography study). The 2024 review counts 511 published cases of filler-related blindness worldwide (2024 review), and a large practitioner survey puts occlusion at about 1 in 6,410 needle syringes against 1 in 40,882 by cannula (practitioner survey). The safeguards are anatomical: a systematic review and meta-analysis supports injection between the superficial and deep temporal fasciae with 18–21-gauge cannulas in small volumes (interfascial meta-analysis), the expert guides map the planes and hazards (expert guide), ultrasound guidance is described (ultrasound-guided technique), and 84% of hyaluronic occlusions recover at least partly with prompt hyaluronidase (pooled analysis). Pain out of proportion, blanching, visual change or headache during a temple injection is an emergency in minutes; ask the injector how many temples a month and where the hyaluronidase is.

The folklore says hyaluronic gel is gone in twelve to eighteen months; the imaging says otherwise. A review of 33 patients with midface MRI found gel persisting for years after injection (MRI review), and 3D-MRI shows the injected volume expanding as the gel draws water rather than disappearing (3D-MRI study). Added to yearly, it accumulates into the swollen, flattened, feature-blurring face that the literature now classifies as facial overfilled syndrome and treats with hyaluronidase (overfilled syndrome), often after gel has migrated from the cheek into the lower face. The rules: volume decided on the photograph rather than the calendar, the medial cheek before the lateral cheekbone, nothing in a face that passed the recline test as sagging, and a clinician who dissolves as readily as they inject.

The collagen stimulators buy their duration with irreversibility. In the 331-person randomised trial, nodules occurred in 10.2% of the poly-L-lactic acid group, mostly mild (superiority trial); papules form when the suspension is placed too superficially, diluted too little or massaged too briefly, and the temple and the orbit are the sites where a nodule shows. Calcium hydroxylapatite lumps in thin skin and is not used in the temple or the tear trough; delayed-onset nodules are reported after 0.02–4.25% of hyaluronic filler treatments, the top of the range with some lower-molecular-weight gels, sometimes after an infection or vaccine (review). No enzyme removes either; a nodule is steroids, time and occasionally a scalpel. Hyaluronic acid first, to learn the face; a stimulator once its behaviour under volume is known.

Fat grafting's routine costs are swelling, donor-site bruising and the uncertainty of survival — 47% pooled retention, so a second session is common (retention meta-analysis). Its rare catastrophe is embolism: fat injected under pressure into an artery of the face travels to the eye or the brain, nothing dissolves it, and autologous fat accounts for a large share of the 511 published cases of filler blindness and of the strokes among them (2024 review). Blunt cannulas, low pressure, small aliquots on withdrawal and the danger zones respected are the surgeon's safeguards. The other harm is the hollow that was bought: buccal fat removed for a sculpted look in the twenties leaves a gaunt midface in the forties, and focused ultrasound over-applied to a thin face dissolves the fat this guide exists to restore (retrospective study). Both are treated like any deflation, with less to build on.