Horton/By S. Bradley

BOSTON – His Colgate smile is ever-present.

His off-ice demeanor is always personable. When he’s on, his shot could seemingly break a hole in a brick wall and his skating stride makes him look like Batman racing to the scene of the crime.

Most of the time, you can paint a pretty word picture when discussing Bruins forward Nathan Horton. Right now, however, you can only use one term to describe him: rattled.

The highly touted power forward who was supposed to solve most of the Bruins’ offensive woes from a year ago is now mired in a slump that you can either track back 17 games (1 goal) or 30 games (4 goals) after he failed to hit the score sheet tonight in a 4-2 loss to Buffalo at TD Garden.

If the lack of scoring – which Boston has managed to overcome lately during a 6-3-1 stretch of play – wasn’t bad enough, Horton’s utter lack of confidence cost the Bruins dearly in the form of giveaways that led directly to Sabres goals.

Horton’s first gaffe occurred along the wall in the defensive zone, as he lost the puck after a hit that could generously be called a love tap. One pass and one rebound off the post later, Buffalo had tied the game at 1.

Then with the game knotted again at 2, Horton passed up a shot from the right circle and instead opted for a backhand pass to the point while facing the Buffalo goal. The pass missed Dennis Seidenberg by a couple feet and sprung Thomas Vanek for an end-to-end rush, which ended with the go-ahead goal beating Tuukka Rask.

Horton wasn’t available to speak after the game about his two miscues or the breakaway he missed a little more than five minutes into the game (he shot wide). He was getting medical treatment from the time the room was open to the media until it was closed.

To be somewhat fair, Horton missed two games earlier this month with what was described as “discomfort” and has been receiving lengthy post-game treatments a lot lately. In the cloak-and-dagger world of NHL injuries, we’ll never know how banged up Horton is until the season is over.

However, when you make the types of mistakes Horton made tonight, and your stat line looks more like that of a fourth-line plumber than that of a sniper who started the season with five goals in six games and has exceeded 27 goals in a season three times, the hurdle you have to clear is more mental than physical.

If Horton’s rattled, his longest-tenured teammate – center Gregory Campbell – isn’t detecting it.

“The thing about him, from what I’ve seen, is he’s confident in himself and he doesn’t let these things bother him,” said Campbell, who also lived the life of a Florida hockey player before last June’s trade to Boston. “That stuff doesn’t get him down. When he’s getting chances, goals aren’t far to come. He had that breakaway in the first period. I’m sure he’ll break out soon.”

Since the calendar turned to 2011, Horton has found a higher level in terms of intensity and force. And in the week and a half since he has been skating with Marc Savard and Michael Ryder, the chances have been plentiful hash mark to hash mark and closer. Sure there have been some bad bounces. There have also been some opportunities that required focus and an undying desire to turn his doldrums into glory days. For a while he looked like he expected that the goals were going to come any second, and now he seems to be skating with his head skyward looking for the next thing to go wrong.

The Bruins have made do without their top line, and their No. 1 sniper, producing much. There’s just so long, however, they can go with Campbell, Shawn Thornton and Brad Marchand providing the bulk of their offense. Horton has to get back on at least a 25-goal pace.

Backhand passes to the point in a tie game aren’t going to end the slump. Breakaways that end with a shot wide from inches in front of the crease are only going to keep the snowball rolling southward.

Happy-go-lucky Horton claimed upon putting on the black-and-gold sweater that nothing could derail his Smile Express. He was just too overjoyed to have been traded from South Florida to an Original Six city. His facial expression might be the same, but his stride’s a little less fluid, his shot’s a little less dangerous, his head seems unable to fathom that his escape to a hockey haven is turning hellish.

Whatever it’s going to take to get Horton’s head straightened out enough so his hands can produce the way he’s supposed to, the Bruins have to find it fast. Their fortunes or reliant on him as a point producer, not just a pretty smile.