Investing genius Peter Lynch liked to say that to find "tenbaggers," that is, stocks that will increase in value by 10 times or more, you should start by looking close to home. In his book One Up on Wall Street, he also noted he liked to seek out companies in dull, disagreeable industries because they were often overlooked or shunned, giving individual investors a chance to purchase them at a discount.

You can't get much closer to home than your mouth, and you can't find something much more dull and disagreeable than a trip to the dentist's office.

When I last wrote about DentsplyInternational (NASDAQ:XRAY), I pointed out that not only was the dental supply company growing earnings at an average annual rate of 16% for the past five years, with free cash flow growing at 23%, but the entire industry had prospects brighter than a smile considering an aging population and the limited longevity of natural teeth. The result is that Dentsply just announced an increase of its cash dividend by 14%, raising it to $0.06 per quarter.

The U.S. dental market boasts some 150,000 dentists with about 70% practicing alone. Only about 10% practice in groups of three or more, meaning the industry is exceptionally fragmented and competitive.

The 100-year-old Dentsply is the leading manufacturer of dental prosthetics, crown and bridge materials, and endodontic instruments and material used in root canals. And it's getting hard for the market to ignore the company's results. In the past five years, the stock price has risen more than 260% and is up more than 400% over the past decade. Yet it still sports a forward P/E ratio of only 19, just a little more than competitor SybronDental Specialties (NYSE:SYD) with a P/E of 16.

Still there are other ways to play an industry that would fulfill Lynch's requirement that it make "people shrug, retch, or turn away in disgust."

For Dentsply to get its products into the hands of dentists (and ultimately into your mouth), it needs distributors. The two dominant players are Patterson Dental (NASDAQ:PDCO) and Henry Schein (NASDAQ:HSIC), which account for about 60% of the market. While there are about 260 companies in the field, Patterson and Schein are the only two publicly traded entities. They buy products from more than 1,000 different manufacturers, including Dentsply. Patterson sells primarily in the U.S. and Canada, while Henry Schein has a greater international presence.

Dentsply believes Japan will be its next big market. It currently derives only 4% of its revenues from Asia, so there is plenty of room to grow. The U.S. and Europe each comprise about 40% of Dentsply's sales.

Whether it's through manufacturers like Dentsply or distributors like Patterson Dental and Henry Schein, investors can mimic Peter Lynch and reap big rewards in dull, depressing, and disagreeable businesses.

Fool contributor Rich Duprey is often accused of being dull, depressing, and disagreeable. He does not own any of the stocks mentioned in this article.