Most offices smell that way from eugenol the active ingredient in clove oil. It is an essential oil and like many essential oils, like those found in mouthwashes, is an antiseptic. Another property of eugenol is that it acts as a weak anesthetic, obviously an advantage in dentistry.
Although the crown cement that once used eugenol, zinc oxide eugenol (ZOE), is not used anymore, there are still several dental uses. Some people still use it in some forms of temporary crown cement. It’s still commonly used in temporary or sedative fillings. It is also still commonly used in the treatment of dry socket. It the past, every time a permanent crown was put in, ZOE would have been taken out and the whole office would get a dose of the eugenol. Now that ZOE is no longer used, most offices do not have that smell anymore. Personally I like the smell and would not mind at all having our office smell like that still today, but maybe that’s a case of the grass is always greener.