He should test the PH of his morning urine. Excess acidity, as in a low PH buffer is what drives tooth decay. If he can improve is diet with ph raising fruits and vegetables he may slow the process down for these new technologies to mature. Another tip is diy mouthwash. Take poultry seasoning and steep it like tea and strain after 20 minutes. Put itvin a glass bottle, keep it in the fridge and let a serving warm up before tooth brush time in the evening. It really can lower plaque. First tip from a holstic dentist, second is mine.