Hi Guest!

D0140 - limited oral evaluation - problem focused
Can be crosscoded to:
99201 - Office or other outpatient visit for the evaluation and management of a new patient, which requires these 3 key components: A problem focused history; A problem focused examination; Straightforward medical decision making. Counseling and/or coordination of care with other physicians, other qualified health care professionals, or agencies are provided consistent with the nature of the problem(s) and the patient's and/or family's needs. Usually, the presenting problem(s) are self limited or minor. Typically, 10 minutes are spent face-to-face with the patient and/or family.
or
99211 - Office or other outpatient visit for the evaluation and management of an established patient, that may not require the presence of a physician or other qualified health care professional. Usually, the presenting problem(s) are minimal. Typically, 5 minutes are spent performing or supervising these services.


D0220 - intraoral - periapical first radiographic image
can be cross coded to:
70300 - Radiologic examination, teeth; single view


D0230 - intraoral - periapical each additional radiographic image
Can be cross coded to:
70310 - Radiologic examination, teeth; partial examination, less than full mouth


As for nitrous, extractions & space maintainers (D9230, D7140 & D1517), there are not direct crosscodes we are aware of for these procedures, so you can either use the "D" code on the medical claim (many insurers these days will process "D" codes when they are medically necessary services), or you can use the CPT code below and include a narrative report describing the procedure:
41899 - Unlisted procedure, dentoalveolar structures


Hope this helps!