<prompt> The advantage of acidulated phosphate fluoride solution is-It is good to taste and can be stored in glass containerNo repeated suction evacuation neededNo effect on existing composite restorationIt has the ability to deposit fluoride in enamel to a deeper depth than neutral sodium fluoride or stannous fluoride  <response>: Advantages of acidulated phosphate fluoride Requires only 2 applications in a year and is thus suited for most dental office routines. The gel preparation can be self applied and thus the cost of application also gets reduced. It has the ability to deposit fluoride in enamel to a deeper depth than neutral sodium fluoride or stannous fluoride APF is stable and need not be freshly prepared for each patient. Disadvantages of acidulated phosphate fluoride Practical difficulties like the teeth should be kept wet for 4 minutes. So repeated applications necessitates the use of suction thereby minimizing its use in the field. This also increases the chair side time making this method more expensive. It is acidic, sour and bitter in taste. It cannot be stored in glass containers. Repeated or prolonged exposure of porcelain or composite restorations to APF can result in the loss of materials, surface roughening and possible cosmetic changes. 