HOUSTON — Wearing brick-red scrubs and chatting in Spanish, Miguel Alquicira settled a tiny girl into an adult-size dental chair and soothed her through a set of X-rays. Then he ushered the dentist, a woman, into the room and stayed on to serve as interpreter.

A male dental assistant, Mr. Alquicira is in the minority. But he is also part of a distinctive, if little noticed, shift in workplace gender patterns. Over the last decade, men have begun flocking to fields long the province of women.

Mr. Alquicira, 21, graduated from high school in a desolate job market, one in which the traditional opportunities, like construction and manufacturing, for young men without a college degree had dried up. After career counselors told him that medical fields were growing, he borrowed money for an eight-month training course. Since then, he has had no trouble finding jobs that pay $12 or $13 an hour.

He gave little thought to the fact that more than 90 percent of dental assistants and hygienists are women. But then, young men like Mr. Alquicira have come of age in a world of inverted expectations, where women far outpace men in earning degrees and tend to hold jobs that have turned out to be, by and large, more stable, more difficult to outsource, and more likely to grow.