erve . ▁The ▁posterior ▁superior ▁al ve olar ▁n erve ▁supplies ▁the ▁ging iva ▁on ▁the ▁fa cial ▁aspect ▁of ▁the ▁max ill ary ▁mol ar ▁teeth . ▁The ▁ging iva ▁on ▁the ▁pal atal ▁aspect ▁of ▁the ▁max ill ary ▁teeth ▁is ▁inner v ated ▁by ▁the ▁greater ▁pal at ine ▁n erve ▁apart ▁from ▁in ▁the ▁in cis or ▁region , ▁where ▁it ▁is ▁the ▁nas op al at ine ▁n erve ▁( long ▁s phen op al at ine ▁n erve ). ▁The ▁ging iva ▁of ▁the ▁ling ual ▁aspect ▁of ▁the ▁mand ib ular ▁teeth ▁is ▁inner v ated ▁by ▁the ▁sub ling ual ▁n erve , ▁a ▁branch ▁of ▁the ▁ling ual ▁n erve . ▁The ▁ging iva ▁on ▁the ▁fa cial ▁aspect ▁of ▁the ▁mand ib ular ▁in cis ors ▁and ▁can ines ▁is ▁inner v ated ▁by ▁the ▁mental ▁n erve , ▁the ▁continu ation ▁of ▁the ▁inferior ▁al ve olar ▁n erve ▁emer ging ▁from ▁the ▁mental ▁for amen . ▁The ▁ging iva ▁of ▁the ▁bu cc al ▁( che ek ) ▁aspect ▁of ▁the ▁mand ib ular ▁mol ar ▁teeth ▁is ▁inner v ated ▁by ▁the ▁bu cc al ▁n erve ▁( long ▁bu cc al ▁n erve ). ▁ ▁Development ▁ ▁The ▁phil tr um ▁is ▁the ▁vertical ▁gro ves ▁in ▁the ▁upper ▁lip , ▁formed ▁where ▁the ▁nas omed ial ▁and ▁max ill ary ▁processes ▁meet ▁during ▁emb ry o ▁development . ▁When ▁these ▁processes ▁fail ▁to ▁f use ▁fully , ▁either