I use day niacinamide for whitening and night hydroxyapatite for enamel repair.

2026-06-19 Toothpaste Reviews Categroy：Toothpaste Views：4

Day niacinamide whitens; night hydroxyapatite repairs. Despite coffee, teeth white. Gentle, probiotic, fluoride-free. I love it!Product Detail

My Day Night Toothpaste Combo Whitens Perfectly

This is a review from Amazon.com about product:

Hydroxyapatite Toothpaste 10% + Niacinamide Whitening Toothpaste - Enamel Repair & Sensitivity Relief, Nano Hydroxyapatite, Fluoride-Free for Gum Care & Fresh Breath, Teeth Whitening

My Day Night Toothpaste Combo Whitens Perfectly

Nice combo! I use the hydroxyappatite in the evening to help my enamel stay where it belongs and the niacinamide in the morning for whiter teeth and fresher breath. I’ve been a heavy tea and coffee drinker my whole life and still have relatively unstained teeth.

Introduction: A User's Experience with MCArthur Day-Night Toothpaste

One satisfied user shared: "Nice combo! I use the hydroxyapatite in the evening to help my enamel stay where it belongs and the niacinamide in the morning for whiter teeth and fresher breath. I've been a heavy tea and coffee drinker my whole life and still have relatively unstained teeth." This review highlights the effectiveness of a dual-action toothpaste system that combines niacinamide for daytime whitening and hydroxyapatite for nighttime enamel repair.

Key Ingredients Explained

Niacinamide (Vitamin B3): Niacinamide is a form of vitamin B3 widely used in skincare and oral care for its brightening and anti-inflammatory properties. In toothpaste, it helps whiten teeth by reducing surface stains, balancing oral pH, and neutralizing acidity from foods and drinks like coffee, tea, and wine. It also works with probiotics to combat stain-causing bacteria, promoting a naturally radiant smile.

Hydroxyapatite: Hydroxyapatite is a naturally occurring mineral that makes up the majority of tooth enamel and bone. In toothpaste, nano-hydroxyapatite (10% in this formula) mimics natural enamel minerals, filling in microscopic weak spots, reducing sensitivity, and repairing enamel, especially during sleep when saliva production decreases. It is a fluoride-free alternative for cavity prevention and strengthens teeth.

Probiotics: Probiotics are beneficial bacteria that help maintain a healthy oral microbiome. In this toothpaste, they work alongside niacinamide to break down plaque gently and fight staining without harsh bleaching agents. They also contribute to fresher breath by balancing oral bacteria.

The Day-Night System: How It Works

MCArthur's toothpaste is designed as a synchronized day and night system. The daytime formula features niacinamide to brighten gums and teeth, neutralize acidity, and provide fresh citrus-mint flavor. The nighttime formula uses 10% nano-hydroxyapatite for biomimetic overnight renewal, rebuilding enamel and repairing micro-cracks while you sleep. Together, they offer 24-hour dual-action protection: day whitening + night repair.

Benefits for Heavy Coffee and Tea Drinkers

Coffee and tea are notorious for staining teeth due to their dark pigments and acidity. The niacinamide in the day formula helps break down and prevent stains, while the hydroxyapatite in the night formula reinforces enamel, making it more resistant to future staining. The probiotic content further supports a clean, stain-free surface. Users report noticeable whitening even with lifelong heavy consumption.

Additional Product Features

This toothpaste is fluoride-free, vegan, dye-free, and cruelty-free. It contains no peroxide, making it safe for sensitive teeth and dental veneers. The flavors are inviting: energizing citrus-mint for day and soothing vanilla-mint for night, both free from artificial sweeteners, parabens, and gluten. The gel form is easy to use, and the 8.32-ounce package is convenient for daily use.

Product Specifications

Why Choose MCArthur Day-Night Toothpaste?

Combining the whitening power of niacinamide with the restorative properties of hydroxyapatite offers a comprehensive oral care routine. The system is gentle yet effective, addressing both cosmetic concerns (whitening) and structural health (enamel repair). For those with sensitive teeth, the fluoride-free probiotic formula provides a safe alternative. The positive user review confirms that even heavy coffee and tea drinkers can maintain white, strong teeth with consistent use.