Which method uses a special adhesive and requires a patch test?

• A. Sewing
• B. Bonding
• C. Fusion
• D. Clip-in

Answer: (B)

Bonding is the method that uses a special adhesive to attach extensions to natural hair, and it requires a patch test to check for any allergic reaction to the adhesive before full application. The patch test places a small amount of the adhesive on a discreet skin area and waits 24–48 hours to make sure there’s no irritation or reaction. This safety step helps prevent dermatitis and ensures the client can tolerate the product.

Sewing uses thread to anchor extensions, not glue. Clip-in extensions attach with small clips, which don’t involve adhesives or patch testing. Fusion involves keratin bonds that are melted with heat to fuse the extensions, which relies on a different bonding method rather than the typical skin patch test for adhesives used in bonding.