Although the effect’s reminiscent of what dental tools would do to a gigantic block of marble, Bing and Yahoo continue to chip away at Google’s lead in the search market, according to new data from Experian Hitwise.  The two companies’ combined market share increased 3.79 percent on a month-over-month basis.

That gave Bing and Yahoo a share of 28.48 percent in February, up from 27.44 percent in January.  Google’s market share, meanwhile, slipped from 67.95 percent to 66.69 percent, a relative decrease of 1.85 percent.

So again, Bing and Yahoo aren’t ready to dethrone Google.  But their progress is hard to deny.  Their market shares have been climbing for several months now, and as the table below shows, Bing isn’t just cannibalizing Yahoo’s user base.

What’s more, Experian Hitwise said in a statement, “Yahoo! Search and Bing achieved the highest success rates in February 2011.  This means that for both search engines, more than 81 percent of searches executed resulted in a visit to a Website.  Google achieved a success rate of 66 percent.”

Finally – although it’s hard to say what this will achieve – we’ll point out that Internet Explorer 9 is supposed to grant users access to certain advanced features on Bing, and the search engine’s market share could increase some more as a result.

Stay tuned, and we’ll be sure to report on the March numbers as soon as they’re available.