Teeth-straightening startup SmileDirectClub Inc. has filed to go public. The Nashville-based company is looking to raise $100 million in its public offering, according to an S-1 the company filed last week. The company has applied to list on Nasdaq under the ticker symbol “SDC,” and J.P. Morgan and Citigroup are the lead underwriters on the deal. SmileDirectClub ships clear aligners directly to customers, whose progress is monitored remotely by licensed dentists or orthodontists.