Gretna found themselves top of the second division courtesy of an early strike from Steve Tosh.
Tosh struck after just four minutes when he fired low into the net from the edge of the box after a neat one-two with Kenny Deuchar.
The Raydale men almost doubled their lead in the seventh minute, but Ryan McGuffie was inches away from connecting to James Grady's low delivery across the face of goal.
The Dumbarton defence were all at sea and Deuchar wasted a glorious chance three mintues later when he shot wide from 10 yards after being set up by David Bingham.
Dumbarton keeper Stephen Grindlay then had to dive low to his left to claw away a downward header from McGuffie after a perfect cross from Gavin Skelton on the half hour mark.
Ryan Baldacchino then raced down the right after being fed by Grady, but the little winger shot inches beyond the far post.
Dumbarton survived another scare in the 37th minute when Craig Brittain hooked the ball off his own goal-line after Grindlay misjudged a back header from Deuchar.
Gretna continued to dominate in the second half but failed to add to their tally due to a combinatioon of poor finishing and some frantic defending from the visitors.
The visitors began to weather the storm for a period as they limited rampant Gretna to a couple of long-range efforts from central defenders Chris Innes and Andy Aitken.