LGT MAKING TURN ON TXWY HAS NOSEWHEEL EXIT TXWY.

Narrative

AFTER LEAVING THE DEICING AREA AT THE RAMP; FLT LEFT FOR TXWY D9. ON TXWY D9 WE WERE MAKING A L TURN ON TXWY D. WHILE THE CAPT BEGAN TO MAKE THE TURN; I WAS ASKED A QUESTION FROM THE FLT ATTENDANT. I TURNED BACK TO ANSWER HER QUESTION; TURNED MY HEAD BACK TO THE FRONT OF THE ACFT AND REALIZED THE NOSE OF THE ACFT HAD LEFT THE TXWY. THE CAPT SAID THAT THE NOSEWHEEL DID NOT RESPOND TO THE TURN. WE WERE TAXIING EXTREMELY SLOW USING ONLY THE #1 ENG. ENG WAS SHUT DOWN; GND NOTIFIED; AND MAINT NOTIFIED. MAINT ARRIVED AT THE ACFT; INSPECTED THE ACFT AND DETERMINED THAT THE NOSEWHEEL HAD JUST DEPARTED THE TXWY. NO DAMAGE WAS EVIDENT TO THE NOSEWHEEL. MAINT TOLD US TO PWR BACK THE ACFT. IT WAS DISCUSSED IN THE COCKPIT. I CHKED MY BOOK AND COULD NOT FIND A PROC AND TOLD THE CAPT. CAPT AND FO DISCUSSED IT. BOTH HAD PWRED BACK ACFT BEFORE. DECIDED TO PWR BACK THE ACFT. ALL ENGS STARTED; ACFT WAS PWRED BACK. WE TAXIED BACK TO THE GATE AND WROTE UP THE NOSEWHEEL IN THE ACFT FORMS. THE ACFT WAS INSPECTED; DETERMINED TO BE OKAY AND THE FLT CONTINUED TO FWA. THINGS LEARNED FROM THIS INCIDENT: SHOULD NOT HAVE TALKED TO FLT ATTENDANT DURING TAXI; EVEN THOUGH I PHYSICALLY COULD NOT DO ANYTHING TO STOP THE ACFT FROM SKIDDING. WHEN I SEE THAT THERE IS NO PROC IN THE BOOK; YOU DON'T THINK ABOUT DOING IT.