Here are a few ways you may be able to repair a minor scratch on your Samsung S8 Plus screen without a full replacement:

• Screen protectors - Adding a high quality screen protector can help fill in and hide superficial scratches. Apply the protector carefully to minimize bubbles.
• DIY scratch repair kits - These contain polishing compounds you rub into the scratch using included tools. Results vary depending on depth.
• Plastic polish - Very fine polishes like Brasso or PlastX can be used gently with a soft cloth to buff out some light surface scratches.
• UV or liquid screen protectants - Products like Liquid Glass or nanocoatings get applied as a liquid and cure via UV light. Some can fill minor scratches.
• Get a professional repair quote - Repair shops may be able to do minor screen refinishing or injections depending on scratch severity. Ask for a quote.

The key is ensuring the scratch truly is minor surface damage only affecting the glass. Deeper scratches likely require a full screen replacement. But methods like polish and protectants are worth trying for light scratch removal to extend the screen's life. Take care not to further damage the display. Replacement remains the surest fix for substantial scratch damage. To learn more or contact Samsung phone screen repair services in Sydney.