Elderly folks are different from us. (Big shock, huh?)
If you live in an area where there are geriatricians, I would recommend making a "get to know you appointment! If you live in an area where a visit to a geriatrician would involve a long drive or other inconvenience, please keep in mind that if you are struggling, or if your loved one is struggling, that inconvenience would pale compared to the benefit that you would probably get from a geriatrician.
Geriatricians have special training to help them be more aware of the needs of elderly people. They are very familiar with conditions and illnesses that tend to be associated with "old age", like incontinence, nutrition, falls/fall prevention and memory problems.
A geriatrician can help with behavior problems and "acting out". If your loved one has any type of problem that is causing your family or the facility stress beyond what is "normal", a geriatrician might be in order.
A geriatrician is also more aware of some of the medication interactions and side effects that elderly people may be more prone to. Since the metabolism of an elderly person is different from that of a younger person, drugs that we wouldn't think twice about can cause significant problems in an elderly person. Many non-geriatrician doctors are very good at what they do, but aren't fully aware of some of the problems that medications can cause.
On the flip side, though, a geriatrician has likely "seen this before", if you are dealing with a specific problem. They are aware of resources and medications that can help. Sometimes just talking to a geriatric team can make you feel less alone, because virtually nothing you tell them about your loved one will be shocking to them, and they can reassure you that you are doing just fine!
If you do not live in an area where a geriatrician is available at least on an as-needed basis, I would suggest that you ask the staff at your loved one's facility (or even at your loved one's clinic, if he or she is not in a facility yet) which doctors seem to be more skilled in treating elderly people, and which doctors are kind and gentle with elderly people--doctors are just regular people like you and me, and many of them are "younger". They may not have had a lot of experience with dementia or other problems of the elderly, so it's good to find someone who has.