So you think 2 times a year is enough? This recommendation was made by insurance companies back in the 1950's when dental insurances were formed.
For very few people one cleaning a year is enough for maintenance. They have minimum risk factors for cavities or bone loss. they may not harvest the bacteria that gives cavities and they maintain optimal home care. But for a lot of us two cleanings a year may not be enough. Each person has different needs because of differences in diet, bacterial flora, immune system, and tooth structure (among other factors).
If your dentist recommends having a cleaning more than 2x a year is for good reason. More than half of U.S. adult population have periodontal disease, which is a serious condition. It results in loss of the bone that supports your teeth. Other reasons for more frequent cleanings include excess of tartar formation, age and number of existing restorations (fillings, crowns, onlays, etc) which require more care. Besides, wouldn't it make sense to prevent cavities or catch them early so you only need a small filling rather than a waiting until you need a crown or even a root cannal treatment?
We are entering a time where we are living longer and most of us want to be at our best at any age. maintaining our teeth as long as possible is one way of looking and feeling younger. Now that you are more informed, see where you stand. make an appontment with your dentist and really consider following the recommendation your dentist makes.