Temple Filler

What is temple filler?

Temple filler is the injection of a filler to add support where the hollow of the temple has lost volume with age. This page describes treatment with hyaluronic acid gel. In studies of temple filler, this was also the substance used in the large majority of treated patients; collagen stimulators and other substances account for a much smaller share of these studies.

As we get older, the fat in the temple decreases, and this leads to hollowing. Research indicates that this hollowing makes the cheekbone arch and the outer rim of the eye socket look more prominent. According to researchers, one reason hyaluronic acid has become widely used in this area is that it is relatively simple to inject.

Hyaluronic acid gels break down in the body over time, which means they are temporary; they can be dissolved with injected hyaluronidase, an enzyme. According to a review of complications from permanent fillers, hyaluronic acid fillers continue to be preferred because they are reversible; permanent fillers, on the other hand, increase the risk of complications in the long term. When the clinic assesses a product, approval by the US Food and Drug Administration (FDA) is not a criterion on its own; the assessment is based on the product’s CE marking, its registration and conformity status in Türkiye, and the manufacturer’s intended purpose.

RELATEDWhat Is Hyaluronic Acid?

SOURCEPMID 40325223PMID 41466484PMID 42499804PMID 42298154

Why do the temples become hollow?

Hollow temples do not have a single cause; changes in more than one layer combine to create the same appearance. Research shows that with age, the bones of the temple become more concave, the temple muscle becomes thinner and the fat pad in the temple shrinks, and that this volume loss gives the face a sunken, thin look.

Changes in the fat have been tracked in the same people over the years. In a study that compared magnetic resonance imaging (MRI) scans of 63 patients taken at least four years apart, the thickness of the subcutaneous fat (the fat layer under the skin) in the temple did not change significantly. The study concluded that hollowing of the temple is mainly caused by thinning of the superficial temporal fat compartment, a separate compartment from this layer.

Temple hollowing is a loss of volume in the hollow of the temple. It can give the face a skeletal look in which the bones stand out, and can contribute to looking older. The degree of hollowing varies from person to person; in studies it is graded as minimal, moderate or severe.

In other words, fat loss, muscle thinning or changes in bone structure can all play a part in hollowing, to different degrees. Which of these is most prominent in your case, and what filler can address in this picture, is assessed at your consultation.

RELATEDWhy does the face sag?

SOURCEPMID 26311237PMID 33649752PMID 39808069

Layers of the temple: where is filler placed?

The temple is made up of many layers stacked on top of each other, from the skin down to the bone; the layer in which filler is placed affects both the result and the risk. An anatomical study using cross-sectional images and three-dimensional models showed three separate layers of fascia (a thin sheet of connective tissue): the superficial temporal fascia (temporoparietal fascia), and the superficial and deep layers of the deep temporal fascia. Separate fat pads were found between these fascial layers and between the deep fascia and the temple muscle.

The structure is even more detailed than this. In a study that used ultrasound to follow 25 women who had hyaluronic acid injected into their temples, 17 separate soft tissue layers were identified in the temple, and the researchers noted that this level of detail calls the usual anatomical descriptions into question. The fact that the layers are named differently from one source to another is also a result of this complexity.

Research does not define a single correct injection plane. Injection between the fascial layers with a cannula (a fine, flexible tube with a blunt tip) and injection with a needle taken down to the bone, placing the filler on the periosteum, are described as separate techniques. Researchers state that there is more than one safe injection plane; according to a guideline prepared by experts, the plane beneath the fascia, within the superficial temporal fat pad or beneath the muscle is chosen according to the person’s anatomy and the intended result.

This difference in naming also matters in practice. When studies of the middle temporal vein (a vein that runs through the temple) were brought together, most of this vein was found to run in the fat pad between the two layers of the deep temporal fascia, and it was suggested that this interfascial plane should be treated as a ‘venous danger zone’. At the clinic, the doctor chooses a needle or cannula individually for each person, based on the treatment area and the anatomy.

SOURCEPMID 42262518PMID 39267731PMID 38480594PMID 39584692PMID 40003675PMID 32472312

Blood vessels and nerves in the temple

The temple is one of the areas of the face that needs care because of its blood vessels; different vessels run in different layers. According to a guideline prepared by experts, the structures that need to be known for safe treatment in this area include the superficial temporal artery, the temporal branch of the facial nerve and the vein known as the ‘sentinel vein’; recognising these risk areas helps to reduce the risk of injury to blood vessels and nerves.

In a study of 209 people that examined scans showing the blood vessels (computed tomography angiography), the superficial temporal artery was found to become thinner and closer to the skin surface from its origin towards the point where it divides. The frontal branch of the artery was reported to run at an average depth of 0.27 cm and 0.21 cm below the skin at its closest points to two reference points on the cheekbone. Another study used the same method to map the course of the superficial temporal artery, the zygomatico-orbital artery (an artery that runs over the cheekbone to the outer rim of the eye socket) and the middle temporal vein in 200 patients. According to this study, accidental injection into these arteries can cause blindness, and injection into the middle temporal vein can cause pulmonary embolism (a blockage of blood vessels in the lungs).

The middle temporal vein needs particular care. When studies of this vein were brought together, its course and depth were reported to be consistent, while its diameter varied between 0.5 and 9.1 mm from study to study. A cadaver study showed a direct connection from the middle temporal vein to the internal jugular vein (the large vein in the neck). This connection has been used to explain how filler that accidentally enters the vein can travel with the blood flow to the lungs and cause a pulmonary embolism that is not caused by a blood clot (non-thrombotic).

Even in the deepest layer, the risk is not zero. A cadaver study of 42 sides of the face and ultrasound measurements in 58 volunteers found that the deep temporal arteries run on average 1.3–2.1 mm from the bone, and that their distribution and depth vary markedly at the level of the eyebrow. The researchers therefore emphasised that extra care is needed.

SOURCEPMID 40003675PMID 40151027PMID 41680307PMID 32472312PMID 26174139PMID 36136301

What does the evidence show?

Scientific evidence on temple filler is growing, but it is still limited. In a systematic review that brought together 40 studies, 19 were prospective (following patients from the start) and 21 were retrospective (looking back at past records); 9 of the retrospective studies were case reports of complications. Of 881 patients in total, 783 were treated with hyaluronic acid. When the data were assessed together, improvements on temple hollowing and overall aesthetic appearance scales were reported, as well as patient satisfaction; the review was rated as level III evidence.

One example of evidence with a control group is a multicentre randomised trial. In this trial, adults with minimal, moderate or severe temple hollowing were randomly assigned either to a hyaluronic acid group or to a control group that received no treatment, and were followed for 13 months. At three months, an improvement of at least one grade in both temples was seen in 80.4% of the treatment group and 13.5% of the control group; the researchers reported that the effect lasted more than a year. Because the trial used a single product, the result cannot be directly applied to other products.

Other studies are smaller. In a single-group study with no control group, in which the treatment given was not concealed (open-label), 26 women were followed for 16 weeks; the gel was placed on the periosteum. A meta-analysis combining data from seven studies that assessed injection between the superficial and deep fascia reported high effectiveness. In 25 women followed with ultrasound, the thickness of the gel was found to decrease between the third and sixth months.

These data do not promise you a result. The studies used different products, different layers and different scales, and their follow-up periods also differ. Much of the information on rare serious complications also comes from case reports, not from controlled studies.

SOURCEPMID 40325223PMID 39808069PMID 37712833PMID 41466484PMID 39267731

Hyaluronic acid or a collagen stimulator?

Hyaluronic acid is not the only type of filler used in the temple, but most research in this area concerns it. In a systematic review of temple treatments, of the 881 patients included, 93 were treated with calcium hydroxylapatite (CaHA), 2 with poly-L-lactic acid (PLLA) and 28 with polymethyl methacrylate, a permanent substance. Temple treatment with collagen stimulators (substances intended to stimulate the skin’s own collagen production) is described separately on the Liquid Facelift with Collagen Stimulators page; the information here is limited to hyaluronic acid.

The benefit of mixing the two types is also less clear than expected. A randomised trial compared pure hyaluronic acid with a hand-mixed combination of hyaluronic acid and CaHA on 40 sides of the face in 20 patients. Over 90 days of follow-up, the mixture did not show the expected effect of the two substances strengthening each other; it was pure hyaluronic acid that maintained volume for longer. The researchers note that mixing by hand may change how the filler behaves. The study is small and its follow-up period is short.

There is also a safety side to the choice. In research on complications of permanent fillers, hyaluronic acid is seen as the preferred option because it is reversible, while permanent fillers are reported to increase the risk of complications in the long term. Which type makes sense for you, and its limits, are discussed at your consultation.

RELATEDLiquid Facelift with Collagen Stimulators

SOURCEPMID 40325223PMID 40860960PMID 42298154

Limits of this treatment

Temple filler targets volume loss in the temple. It does not remove excess skin, does not release and reposition sagging tissue as surgery does and is not a substitute for a surgical facelift. The term ‘lift’, often used in filler publications, has no agreed definition, no accepted measurement standard and no validated threshold for what counts as clinically meaningful. According to a critical review, all published numerical measurements reflect changes at the skin surface. The researchers state that this does not mean fillers have no such effect; it shows that the effect has not yet been defined with the necessary precision.

Hyaluronic acid is not permanent. According to a review of hyaluronic acid gels, the clinical effect usually lasts 4–18 months, depending on the product, the technique and the person; in the temple study with ultrasound follow-up, the thickness of the gel also decreased within six months. These figures are not a promise of how long the effect will last, and they cannot tell you how long it will last in your case.

The amount used is also a limit. According to assessments on this subject, the risk of filler migration and an overfilled look does not come from the product itself; it is linked to insufficient knowledge of anatomy, unsuitable technique, or unsuitable patient selection and patient information. More volume does not mean a more harmonious face.

The final limit is the scientific evidence itself: publications on temple filler consist largely of small studies and case reports. In any treatment, knowing where to stop is as important as knowing how far you can go.

SOURCEPMID 42620772PMID 42499804PMID 39267731PMID 40325223

Known risks

The most common side effects of temple filler are pain or a feeling of pressure, bruising and swelling. In a systematic review of temple treatments, the most frequently reported adverse effects were pain, tenderness or a feeling of pressure (29.6%), bruising (17.3%) and oedema (15.5%); vascular events and other serious adverse events were reported rarely. These figures are averages from published studies, not results from this clinic.

A complaint specific to the temple is pain or discomfort when chewing. It has been reported that deeper injections may be more often linked to this complaint; these are injections placed on the periosteum, or between or within the fascial layers. Side effects reported after treatment in this area also include bruising, tenderness, swelling, bluish discolouration under the skin (Tyndall effect), overcorrection and discomfort when chewing. Rare but serious ones are infection, foreign body granuloma (a cluster of tissue the body forms in reaction to a foreign substance), tissue death caused by injection into a blood vessel, and blindness caused by blockage of the artery of the eye (embolism).

There is also a risk affecting the scalp. A case has been reported in which skin tissue death and hair loss developed in an area with impaired blood flow after hyaluronic acid was injected into the temple; the condition improved with treatment. A case of scarring partial hair loss without signs of vascular occlusion has also been published; the researchers who reported it stated that hair loss caused by filler is rare and identified 17 cases in total, including this one.

Side effects can also appear outside the treatment area and at a later stage. In a patient who came in with persistent swelling of the upper eyelids two years after a temple treatment, deposits consistent with hyaluronic acid were found in the tissue; because the diagnosis was delayed, surgery was needed. Research on complications of permanent fillers emphasises that, in permanent damage, the treatment site, the technique and the permanence of the filler matter more than the amount of filler alone.

RELATEDWhat to Expect After a Treatment

SOURCEPMID 40325223PMID 26311237PMID 36857561PMID 40607771PMID 41959944PMID 42298154

Vascular occlusion and vision loss

The most serious risk of temple filler is filler entering an artery and disrupting the blood supply to tissue or to the eye. It is rare, but its consequences can be permanent. A review updating cases of vision loss reported after facial fillers identified 365 new cases; the highest-risk areas were reported to be the nose, the forehead and the area between the brows (glabella). Among the cases in which the later state of vision was reported, vision did not return in 68.2%.

The temple is not at the top of this list, but it is not outside it. In a case series of six patients who developed vision loss after hyaluronic acid injections in the face, one patient had had a temple treatment; in all of the cases, vision loss was caused by filler blocking the arteries of the retina or the eye (embolism). A study of images of the carotid arteries (carotid angiograms) identified four possible connection routes from the deep temporal arteries, which run in the plane on the periosteum, to the artery of the eye. According to the researchers, this plane, which guidelines recommend for safety, also carries risk because of the deep temporal arteries; the chance of filler following these routes may be low, but it is not impossible.

Early recognition determines the outcome. In a systematic review and meta-analysis of vascular occlusions after filler, timely recognition and treatment were associated with better recovery, and a delay of more than five days was associated with permanent damage. According to a review on hyaluronidase, emergencies such as vascular occlusion and blindness also require immediate treatment with hyaluronidase.

Consensus guidelines produced by a multidisciplinary group in the United Kingdom highlight the urgent first steps in filler-related vision loss, the routes to specialist care and improvements to the consent process (agreeing to treatment after being given full information). How you can reach the clinic if symptoms appear depends on the clinic’s own protocol; you should be given this information before your treatment.

SOURCEPMID 38630871PMID 30006992PMID 39749811PMID 40406769PMID 38231537PMID 41490283

Temples previously treated with filler

If your temples have had filler before, the first question before any new treatment is what the existing filler is. Hyaluronic acid fillers can be dissolved with the enzyme hyaluronidase. In research on the use of hyaluronidase, non-urgent problems such as bluish discolouration under the skin (Tyndall effect) and non-inflammatory nodules (small firm lumps) are considered separately from emergencies such as vascular occlusion. Controlled study data in this area are limited, but clinical experience is growing.

There is no way to dissolve permanent fillers with an enzyme; according to research, these fillers increase the risk of complications in the long term. The case of a patient who developed eyelid swelling two years after a temple treatment also shows why it matters to know about earlier treatments: the patient remembered the temple treatment only after surgery. The researchers who reported the case emphasise that detailed questions about past aesthetic treatments are important in reducing the risk of misdiagnosis.

Hyaluronidase is kept at the clinic. For fillers done elsewhere, the type, timing and site of the filler are asked about first; fillers of unknown type, or fillers that cannot be confirmed as hyaluronic acid, are not dissolved straight away. If you have a record of the previous treatment, this information is useful at your consultation.

RELATEDFiller Dissolving

SOURCEPMID 38231537PMID 42298154PMID 41959944