UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

GRAYMARK HEALTHCARE, INC.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

389465303

(CUSIP Number)

Marcelo Puiggari, Esq.

General Counsel & VP Legal Services

Foundation HealthCare Affiliates, LLC

14000 N. Portland Ave., Suite 204

Oklahoma City, OK 73134

(405) 608-1735

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

With copies to:

Eulalia M. Mack

Reed Smith LLP

599 Lexington Avenue

New York, New York 10022

Telephone: (212) 521-5400

July 22, 2013

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ¨

SCHEDULE 13D

The securities covered by this Schedule 13D are shares of common stock, $0.0001 par value, of Graymark Healthcare, Inc., an Oklahoma corporation (the “Issuer”). The Issuer’s principal executive offices are located at 204 N. Robinson Ave., Ste. 400, Oklahoma City, OK 73102.

This statement is filed by Foundation Healthcare Affiliates, LLC, an Oklahoma limited liability company (the “Reporting Person”). The Reporting Person is a healthcare development and management company operating ambulatory surgery centers and surgical hospitals, with its principal business address at 14000 N. Portland Avenue, Suite 203, Oklahoma City, OK, 73134. Set forth on Schedule I hereto is the name, citizenship, business or residence address and present principal occupation or employment, as well as the name and address of any corporation or other organiation in which such occupation or employmet is conducted, of each of the members of the Reporting Person’s Board of Managers and each executive officer of the Reporting Person.

The Reporting Person has not, during the last five years, (a) been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (b) been party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

The information contained in Item 4 is incorporated by reference into this Item 3. As described in Item 4, the 114,500,000 shares of common stock that are the subject of this Schedule 13D (the “Shares”) were acquired by the Reporting Person in the Acquisition (as defined below) in exchange for all of the outstanding membership interests of Foundation Surgery Affiliates, LLC and Foundation Surgical Hospital Affiliates, LLC (together the “Companies” or “Foundation”) as well as assets of the Reporting Person related to the businesses of the Companies. The Reporting Person was the sole equity owner of the Companies prior to consummation of the Acquisition. In consideration for the Acquisition, in addition to the issuance of the Shares, the Issuer assumed certain liabilities and obligations of the Reporting Person. In accordance with the Amended Purchase Agreement (as defined below), as further consideration for the equity interests of the Companies, a demand promissory note in the principal amount of $2,000,000 was also issued by the Issuer to the Reporting Company at the closing of the Acquisition (the “Closing”).

The Reporting Person acquired the securities described in this Schedule 13D in connection with the consummation on July 22, 2013, of the acquisition (the “Acquisition”) by the Issuer through its wholly owned subsidiary, TSH Acquisition, LLC (“Acquisition Sub”), from the Reporting Person of all of the membership interests of the Companies pursuant to the terms and conditions of the Amended and Restated Membership Interest Purchase Agreement, dated as of March 29, 2013, as amended by the First Amendment to Amended and Restated Membership Interest Purchase Agreement, dated as of July 22, 2013, among the Issuer, Acquisition Sub and the Reporting Person (as so amended, the “Amended Purchase Agreement”).

Prior to the completion of the Acquisition, the Reporting Person held all of the equity interests of the Companies. Pursuant to the terms of the Amended Purchase Agreement and effective upon the completion of the Acquisition, the Reporting Person acquired beneficial ownership of the Shares, and the Issuer assumed certain liabilities and obligations of the Reporting Person, as described in Item 3. The Reporting Person acquired such Shares for investment purposes and with the intent to obtain a substantial ownership interest in the Issuer in order to be able to influence the business and management of the Issuer. The Reporting Person disclaims any membership in a group relating to the Issuer. Subject to the information contained in this Item 4 and Item 6, which is incorporated by reference into this Item 4, depending upon market conditions and other factors that the Reporting Person deems material, after the date of this Schedule 13D the Reporting Person may purchase additional shares of common stock or other securities of the Issuer in the open market, in private transactions or from the Issuer, or may dispose of all or a portion of the shares of common stock (including the Shares) or other securities of the Company that the Reporting Person now owns or hereafter may acquire.

The Amended Purchase Agreement provides that at or prior to the Closing, the Issuer’s Board of Directors would appoint Mr. Thomas Michaud, Chief Executive Officer of the Reporting Person, and up to six other directors designated by the Reporting Person to serve until the next annual meeting of the Issuer following the Closing. In accordance therewith, concurrently with the Closing, Ms. Jamie Hopping and Dr. S. Edward Dakil resigned from the Board of Directors of the Issuer and the Board of Directors appointed Mr. Michaud and Dr. Robert Moreno, the Reporting Person’s designee, to fill the vacancies created thereby. The remaining four directorships continue unchanged. The Amended Purchase Agreement also provides that Mr. Michaud will be appointed Chairman. Inherent in his Board membership and in such position, Mr. Michaud will participate in and influence the affairs of the Issuer. In addition, the Reporting Person also may participate in and influence the affairs of the Issuer through the exercise of voting rights with respect to the beneficial ownership of the Shares. The Reporting Person has no registration rights.

Other than as described in this Schedule 13D, the Reporting Person does not have any present plans or proposals that relate to, or that would result in, any of the events described in paragraphs (a) to (j) of Item 4 of the Schedule 13D instructions. The Reporting Person reserves the right to formulate plans or make proposals, and take such actions with respect to its investment in the Issuer, including any or all of the items specified in paragraphs (a) to (j) of Item 4 of the Schedule 13D instructions and any other actions as it may determine.

The disclosures in Item 4 above are incorporated by reference into this Item 5. The Reporting Person is the beneficial owner of the Shares, constituting approximately 70.2% of the Issuer’s outstanding shares of common stock. Such percentage is based upon 163,203,276 shares of the Issuer’s common stock outstanding as of July 22, 2013, as reported in the Issuer’s Current Report on Form 8-K filed on July 26, 2013. The Reporting Person has sole power to vote and direct the vote of all Shares.

Except in connection with the acquisition of the Shares described in Items 4 and 5 of this Schedule 13D, the Reporting Person has not effected any transactions in the Issuer’s common stock during the sixty days prior to the date of this Schedule 13D.

There are no other contracts, arrangements, understandings, or relationships (legal or otherwise) between Reporting Person and any other person with respect to the Shares beneficially owned by the Reporting Person.

SIGNATURE

After reasonable inquiry and to the best of such Reporting Person’s knowledge and belief, the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated: August 1, 2013

Schedule I

Members of the Board of Managers and Executive Officers of

Foundation HealthCare Affiliates, LLC

July 31, 2013

Exhibit Index

Exhibit 2

EXECUTION COPY

FIRST AMENDMENT TO AMENDED AND RESTATED MEMBERSHIP INTEREST

PURCHASE AGREEMENT

This First Amendment to Amended and Restated Membership Interest Purchase Agreement (this “Amendment”), dated as of July 22, 2013 (the “Effective Date”), is entered into among Foundation Healthcare Affiliates, LLC, an Oklahoma limited liability company (“Seller”), TSH Acquisition, LLC, a Delaware limited liability company (“Buyer”), and Graymark Healthcare, Inc., an Oklahoma corporation (“Parent” and together with the Seller and Buyer, the “Parties”).

RECITALS

WHEREAS, Seller and Buyer entered into that certain Amended and Restated Membership Interest Purchase Agreement dated as of March 29, 2013 (the “Purchase Agreement”), pursuant to which Seller agreed to sell and Buyer agreed to purchase (i) all of the issued and outstanding membership interests (the “FSA Membership Interests”) in Foundation Surgery Affiliates, LLC, a Nevada limited liability company, and (ii) all of the issued and outstanding membership interests (together with the FSA Membership Interests, the “Membership Interests”) in Foundation Surgical Hospital Affiliates, LLC, a Nevada limited liability company, all as more particularly described in the Purchase Agreement.

WHEREAS, the Parties desire to amend the Purchase Agreement to update the Purchase Price Seller shall receive from Buyer in connection with the sale of the Membership Interests.

AGREEMENT

NOW, THEREFORE, in consideration of the mutual rights and obligations hereunder, the Parties hereby agree as follows:

““Parent Common Shares” means 114,500,000 shares of Parent Common Stock issued at Closing.”

““Post-Closing Tax Period” means any taxable period beginning after the Tax Effective Date and, with respect to any taxable period beginning before and ending after the Tax Effective Date, the portion of such taxable period beginning after the Tax Effective Date.”

““Pre-Closing Tax Period” means any taxable period ending on or before the Tax Effective Date and, with respect to any taxable period beginning before and ending after the Tax Effective Date, the portion of such taxable period ending on and including the Tax Effective Date.”

““Amendment” means the First Amendment to Amended and Restated Membership Interest Purchase Agreement, entered into by and among Buyer, Seller and Parent, dated as of July 22, 2013.”

““Note” has the meaning set forth in Section 2.2(c).”

““Tax Effective Date” means July 1, 2013.”

“Section 2.2 Purchase Price. The aggregate purchase price (the “Purchase Price”) for the Membership Interests and the Additional Purchased Assets shall be:

“(i) the Purchase Price, by delivery to Seller of a stock certificate registered in the name of Seller representing the Parent Common Shares and the Note executed by a duly authorized officer of Parent.”

“For tax and accounting purposes the Closing shall be deemed to be effective as of the Tax Effective Date.”

“(b) Without the prior written consent of Buyer, Seller (and, prior to the Closing, each Company, their Affiliates and their respective Representatives) shall not, to the extent it may affect, or relate to, any Company, make, change or rescind any Tax election, amend any Tax Return or take any position on any Tax Return, take any action, omit to take any action or enter into any other transaction not in the ordinary course of business consistent with past practice that would have the effect of increasing the Tax liability or reducing any Tax asset of Buyer or a Company. Seller agrees that Buyer is to have no liability for any Tax resulting from any action of Seller, any Company, their respective Affiliates or any of their respective Representatives taken prior to the Tax Effective Date, and agrees to indemnify and hold harmless Buyer (and, after the Closing Date, each Company) against any such Tax or reduction of any Tax asset.”

“Section 6.3. Tax Indemnification. Seller shall indemnify each Company, Buyer, and each Buyer Indemnitee and hold them harmless from and against: (a) any Loss attributable to any breach of or inaccuracy in any representation or warranty made in Section 3.25; (b) any Loss attributable to any breach or violation of, or failure to fully perform, any covenant, agreement, undertaking or obligation in Article VI; (c) all Taxes of the Seller or any Company for all Pre-Closing Tax Periods; (d) all Taxes required to be paid or withheld by the Seller or any Company for all Pre-Closing Tax Periods; (e) all Taxes of any member of an affiliated, consolidated, combined or unitary group of which the Company (or any predecessor of the Company) is or was a member on or prior to the Tax Effective Date by reason of a liability under Treasury Regulation Section 1.1502-6 or any comparable provisions of foreign, state or local Law; and (f) any and all Taxes of any person imposed on a Company arising under the principles of transferee or successor liability or by contract, relating to an event or transaction occurring before the Tax Effective Date, in each of the above cases, together with any out-of-pocket fees and expenses (including attorneys’ and accountants’ fees) incurred in connection therewith. Seller shall reimburse Buyer for any Taxes of a Company that are the responsibility of Seller pursuant to this Section 6.3 within ten Business Days after payment of such Taxes by Buyer or the Company.

Parent shall indemnify Seller and each Seller Indemnitee and hold them harmless from and against (i) any Loss attributable to any breach of or inaccuracy in any representation or warranty made in Section 4.11, and (ii) any Loss attributable to any breach or violation of, or failure to fully perform, any covenant, agreement, undertaking or obligation in Article VI, in each case, together with any out-of-pocket fees and expenses (including attorneys’ and accountants’ fees) incurred in connection therewith.

IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed effective in all respects as of the Effective Date set forth above.

[SIGNATURES ON FOLLOWING PAGE]

SIGNATURE PAGE TO FIRST AMENDMENT TO AMENDED AND RESTATED

MEMBERSHIP INTEREST PURCHASE AGREEMENT

EXHIBIT A

Promissory Note (Demand)

PROMISSORY NOTE (DEMAND)

1. Principal Amount. For Value Received, Graymark Healthcare, Inc., an Oklahoma corporation, (“Maker”), promises to pay to the order of Foundation Healthcare Affiliates, LLC (“Payee”), the principal amount of two million dollars ($2,000,000.00), payable at the times specified in paragraph 3 hereof.

2. Interest. Maker also promises to pay interest on the unpaid principal amount hereof from the date hereof until such unpaid principal amount is paid in full, at the per annum rate of seven percent, (7%), payable at the times specified in paragraph 3 hereof.

3. Payments. The principal balance shall be paid by Maker to Payee, on demand. Interest on the unpaid balance at the rate set forth above shall be paid monthly, commencing 30 days from the date hereof and continuing on the same day of each month thereafter until paid in full. All payments shall be payable in U. S. dollars and directed to Payee’s offices at 14000 N. Portland Ave., Suite 203, Oklahoma City, OK 73134, unless Maker is otherwise notified in writing by Payee.

4. Application of Payments. All payments made by Maker to Payee pursuant to this Note shall be applied first to accrued and unpaid interest and the balance, if any, to unpaid principal.

5. Post-Maturity Interest; Computation of Interest. Any amount of principal and/or interest hereof which is not paid when due, whether at stated maturity or by acceleration, shall bear interest from the date when due until said principal and/or interest amount is paid in full, at an interest rate of one and one-half per cent (1.5%) per month; provided however, that in no event shall the interest contracted for, charged, received, paid, or agreed to be paid to the holder hereof, exceed the maximum amount permissible under applicable law. If, from any circumstance whatsoever, interest would otherwise be payable to the holder hereof in excess of the maximum lawful amount, the interest payable to the holder hereof shall be reduced to the maximum amount permitted under applicable law, and if from any circumstance the holder hereof shall ever receive anything of value deemed interest by applicable law in excess of the maximum lawful amount, an amount equal to any excessive interest shall be applied to the reduction of the principal hereof and not to the payment of interest, or if such excessive interest exceeds the unpaid balance of principal hereof, such excess shall be refunded to Maker. Interest shall be computed on the basis of a year of 360 days.

6. Default. At the option of Payee and upon demand, it shall be considered an event of default (“Event of Default”) if any of the following occurs and such Event of Default remains uncured ten (10) days following a notice of default given by Payee to Maker:

7. Remedies. After the occurrence of an Event of Default, this Note shall, at the option of Payee, become due and payable forthwith, without demand upon or further notice to the undersigned, and upon occurrence of any Event of Default or nonpayment of any amounts due hereunder, Payee shall have all of the rights and remedies provided under applicable law and in equity. Failure to exercise this option shall not constitute a waiver of the right to exercise the same at any other time.

8. Waiver. Maker hereby: (i) waives presentment, demand, protest and notice of dishonor; and (ii) agrees that its liability hereunder shall not be affected by any neglect or omission of Payee to exercise any remedies of set-off. Any failure by Payee to exercise any right hereunder shall not be construed as a waiver of the right to exercise the same or any other rights at any other time.

9. Transfer of Note. Payee may transfer this Note and assign its rights to any transferee and such transferee shall become vested with all the powers and rights herein and therein given to Payee. Thereafter, Payee shall be forever relieved and fully discharged from any liability or responsibility in connection with this Note.

10. Choice of Law; Venue. THIS NOTE, ITS SCHEDULES, RIDERS, ANCILLARY DOCUMENTS AND AMENDMENTS THERETO SHALL BE GOVERNED IN ALL RESPECTS BY THE LAWS OF THE STATE OF OKLAHOMA. IN ORDER TO INDUCE MAKER TO EXECUTE THIS NOTE, MAKER HEREBY AGREES THAT ALL ACTIONS OR PROCEEDINGS ARISING DIRECTLY OR INDIRECTLY FROM THIS NOTE SHALL BE LITIGATED ONLY IN COURTS (STATE OR FEDERAL) HAVING SITUS IN THE STATE OF OKLAHOMA AND THE COUNTY OF OKLAHOMA UNLESS PAYEE, IN ITS SOLE DISCRETION, WAIVES THIS PROVISION. MAKER HEREBY EXPRESSLY SUBMITS AND CONSENTS IN ADVANCE TO SUCH JURISDICTION IN ANY ACTION OR PROCEEDING COMMENCED BY PAYEE IN ANY STATE OR FEDERAL COURT LOCATED WITHIN THE STATE OF OKLAHOMA. MAKER WAIVES ANY CLAIM THAT ANY ACTION INSTITUTED BY PAYEE HEREUNDER IS IN AN INCONVENIENT FORUM OR AN IMPROPER FORUM BASED ON LACK OF VENUE. TO THE EXTENT PERMITTED BY LAW, MAKER HEREBY WAIVES TRIAL BY JURY AND ANY RIGHT OF SETOFF OR COUNTERCLAIM IN ANY ACTION BETWEEN PAYEE AND MAKER.

11. Expenses of Enforcement. Maker promises to pay all costs and expenses, including reasonable attorneys’ fees incurred in the collection and enforcement of this Note.

12. Counterparts; Facsimile Execution. The Note may be executed in any number of counterparts and by different parties on separate counterparts, each of which, when executed and delivered, shall be deemed to be an original, and all of which, when taken together, shall constitute but one and the same Note. Delivery of an executed counterpart of this Note by facsimile shall be equally as effective as delivery of a manually executed counterpart. If Maker delivers an executed counterpart of this Note by facsimile, Maker shall also deliver a manually executed counterpart of the Note, but the failure to deliver a manually executed counterpart shall not affect the validity, enforceability, and binding effect of this Note.

IN WITNESS WHEREOF, Maker has executed and delivered this Note as of the date and year first above written.