If you reside in the city limits of Dayton, you are required to file a Dayton City income tax return, regardless of where you work, unless your employer withheld the correct amount of Dayton tax.
Dayton allows a full credit for tax paid to other cities. Kettering has a 2.25% tax rate and Dayton was 2.25% until 1-1-17 (when it went to 2.5%). So, you did not have to file a Dayton return in the past, because the Kettering withholding that your employer did was adequate. If you employer is not now withholding an additional 0.25% for Dayton, you will have to now file a Dayton return.
Your wife has essentially the same situation, but only for part of the year. It may be simpler for you to file separate city tax returns (the tax rate is the same married separately or jointly). You may also have to file a 2017 return.
[EDIT] Dayton will accept CCA forms. So you can do the Dayton form in TurboTax.
City web site: https://www.daytonohio.gov/262/Tax-Information-Forms
