Temporal Triangular Alopecia: A Stable Hairless Patch

Temporal triangular alopecia (TTA) — also called congenital triangular alopecia — is a benign, non-scarring patch of hair loss that usually appears in the frontotemporal (“temple”) area. The key feature is that it is typically stable (not rapidly spreading) and the follicles are preserved.

Medical note: This article is for general education and does not provide personal medical advice. For the full roadmap, start here: Hair Loss (Complete Guide).

Temporal triangular alopecia: a stable, triangular or spear-shaped patch of thinning at the temple (non-scarring). — Temporal triangular alopecia is a non-scarring, usually stable patch of thinning at the temple area. It often contains fine vellus hairs on close exam.

What is temporal triangular alopecia?

Temporal triangular alopecia is a localized, non-scarring alopecia most often found in the frontotemporal region. It’s considered benign and usually non-progressive once established. Many cases are noticed in early childhood, but it can be recognized later as well.

On our site, this belongs under: Non-Scarring Alopecia (Hub) and the big-picture map: Types of Hair Loss.

What it usually looks like

Typical clues include:

Location: one-sided (unilateral) patch at the temple/frontotemporal scalp
Shape: triangular, oval, or “spear-shaped” area
Skin: normal-looking scalp (no thick scale, no shiny scar, no pustules)
Course: often stable over time

Why it happens (simple mechanism)

The exact cause isn’t fully settled. The practical takeaway is that TTA is not scarring and typically involves a localized pattern of miniaturization (fine vellus hairs may be present in the patch), rather than follicle destruction.

Trichoscopy clues (how it’s confirmed)

Trichoscopy/dermoscopy is the easiest way to confirm TTA and avoid misdiagnosis (especially as alopecia areata). Common findings include:

Normal follicular openings (supports non-scarring)
Vellus hairs throughout the patch (often variable lengths)
Absent alopecia areata clues like black dots, broken hairs, or exclamation-mark hairs

Trichoscopy in temporal triangular alopecia: normal follicular openings with vellus hairs in the patch. — Trichoscopy often shows normal follicular openings with vellus hairs across the patch, helping distinguish TTA from alopecia areata.

Conditions that can look similar (important)

TTA is commonly confused with other localized hair loss. Use these quick distinctions:

Alopecia areata: usually sudden smooth patches; trichoscopy may show black dots, exclamation-mark hairs.
Read: Alopecia Areata.
Trichotillomania: irregular patches with hairs of different lengths + broken hairs.
Read: Trichotillomania.
Traction alopecia: hair loss from pulling/tension; often edges/hairline with a traction pattern.
Read: Traction Alopecia.
Tinea capitis: more likely with scale, black dots, broken hairs, itch, or in children.
Read: Tinea Capitis.
Scarring alopecia: shiny smooth skin, loss of follicle openings, pain/burning → evaluate promptly.
Hub: Scarring Alopecia.

How it’s diagnosed

Diagnosis is usually clinical + trichoscopy. In unclear cases, clinicians may consider additional evaluation, but most cases do not need extensive testing.

What to do (safe next steps)

Confirm the diagnosis: a quick trichoscopy check can prevent unnecessary steroid treatments for “alopecia areata.”
Document stability: take a clear photo monthly for 3–6 months (same lighting).
Be cautious with self-treatment: if there is scale/itch/pain or rapid spread, re-check the diagnosis.

Treatment (cosmetic options)

Many people choose no treatment once reassured. If cosmetic correction is desired, options are typically procedural:

Hair transplantation (follicular unit methods are commonly reported)
Surgical excision in small lesions (case-dependent)

When to see a doctor (red flags)

Rapid expansion over weeks (TTA is usually stable)
Thick scale, crusting, pustules, or significant itch (consider infection/inflammation)
Pain, burning, tenderness or loss of follicle openings
Multiple new patches or a new generalized shedding pattern

Read: When to See a Doctor.

FAQ

Is temporal triangular alopecia permanent?

It’s usually long-standing and stable, but it’s non-scarring (follicles are preserved). People often keep the patch unless they choose a cosmetic procedure.

Does it spread?

Classically it remains stationary. Rapid changes should prompt re-evaluation for look-alike conditions.

Can it be mistaken for alopecia areata?

Yes — that’s one of the most common errors. Trichoscopy helps distinguish them by showing vellus hairs and normal openings without classic areata signs.

References (trusted medical sources)

Last updated: February 02, 2026.