Please select the eligibility criteria that correspond to the clinical trial below.
Title: Ridge Preservation Following Tooth Extraction Using Mineralized Freeze-Dried Bone Allograft Compared to PUROS Mineralized Bone Allograft
Brief Summary: The study is a 2-arm, parallel-design, randomized, prospective clinical trial designed to examine histologic wound healing following ridge preservation using bone allograft that has been prepared by either freeze-drying or via a non-freeze-dried solvent process.This entire protocol involves procedures that are standard care. All materials are FDA-approved materials being used in an FDA-approved manner. The test group subjects will have extraction sockets grafted with a cancellous non-freeze-dried bone allograft (called PUROS graft). This test group will be compared to an active control group using cancellous freeze-dried bone allograft (called FDBA). The null hypothesis is that there will be no significant difference in formation of new vital bone between treatment groups (primary outcome).

Each subject will provide a single non-molar tooth site for study treatment. After tooth extraction, the graft material will be placed and covered by a resorbable collagen membrane. Following 3 months of healing, the dental implant will be place, at which time a core of bone will be removed from the site as part of the preparation for the implant. The core biopsy will then be evaluated for the primary histologic outcome of % vital bone formation and secondary histologic outcome of % residual graft material.


Options:
A: Inclusion Criteria:

* Patients will be included in this study if they qualify the following inclusion criteria:
* Live within 50 miles from the School of Dentistry, University of Texas Health Science Center at San Antonio
* Are able to attend a minimum of 6 visits over a 4-5 month period, as required by the study protocol
* A single rooted tooth that has been identified as requiring extraction
* Desire a dental implant to replace the missing tooth
* Have adequate restorative space for a dental implant-retained restoration
* Have at least 10mm of alveolar bone height, without impinging on the maxillary sinus or inferior alveolar canal.
* Have a dehiscence of the buccal or lingual bony plate of the tooth socket extending no more than 50% of the total depth of the socket.
* Female patients who have undergone a hysterectomy, tubal ligation, or menopause, and non-pregnant women of child-bearing potential.
* Are nonsmokers or former smokers. Current smokers may only be included if they smoke \<10 cigarettes per day

Exclusion Criteria:

* Patients who live more than 50 miles from the School of Dentistry, University of Texas Health Science Center at San Antonio
* Patients who do not meet all the inclusion criteria or who will not cooperate with the required follow-up schedule.
* Patients will are mentally incompetent, prisoners, or pregnant.
* Pregnant women or women intending to become pregnant during the study period.
* Smokers who smoke \>10 cigarettes per day
* Clinical and/or radiographic determinations which will preclude inclusion in this study are: Active infection other than periodontitis; Inadequate bone dimensions or restorative space for a dental implant; Presence of a disease entity, condition or therapeutic regimen which decreases probability of soft tissue and bony healing, e.g., poorly controlled diabetes, chemotherapeutic and immunosuppressive agents, autoimmune diseases, history of bisphosphonate use or long-term steroid therapy
* Positive medical history of endocarditis following oral or dental surgery.
B: Inclusion Criteria:Patients will be included in this study if they qualify the following inclusion criteria:

* Live within 50 miles from the School of Dentistry, University of Texas Health Science Center at San Antonio
* Are able to attend a minimum of 6 visits over a 4-5 month period, as required by the study protocol
* A single rooted tooth that has been identified as requiring extraction
* Desire a dental implant to replace the missing tooth
* Have adequate restorative space for a dental implant-retained restoration
* Have at least 10mm of alveolar bone height, without impinging on the maxillary sinus or inferior alveolar canal.
* Have a dehiscence of the buccal or lingual bony plate of the tooth socket extending no more than 50% of the total depth of the socket.
* Female patients who have undergone a hysterectomy, tubal ligation, or menopause, and non-pregnant women of child-bearing potential.
* Are nonsmokers or former smokers. Current smokers may only be included if they smoke \<10 cigarettes per day

Exclusion Criteria:

* Patients who live more than 50 miles from the School of Dentistry, University of Texas Health Science Center at San Antonio
* Patients who do not meet all the inclusion criteria or who will not cooperate with the required follow-up schedule.
* Patients will are mentally incompetent, prisoners, or pregnant.
* Pregnant women or women intending to become pregnant during the study period.
* Smokers who smoke \>10 cigarettes per day
* Clinical and/or radiographic determinations which will preclude inclusion in this study are: Active infection other than periodontitis; Inadequate bone dimensions or restorative space for a dental implant; Presence of a disease entity, condition or therapeutic regimen which decreases probability of soft tissue and bony healing, e.g., poorly controlled diabetes, chemotherapeutic and immunosuppressive agents, autoimmune diseases, history of bisphosphonate use or long-term steroid therapy; Positive medical history of endocarditis following oral or dental surgery.
* Sensitivity or allergy to Bacitracin, Gentamicin, Polymyxin B Sulfate, alcohol and/or surfactants
C: Inclusion Criteria:

* Patients will be included in this study if they qualify the following inclusion criteria:

  * One molar tooth that has been identified by dental faculty as requiring a single tooth extraction
  * A dental implant is indicated and treatment planned to replace the missing molar tooth
  * Have adequate restorative space for a dental implant-retained restoration
  * Have at least 10mm of alveolar bone height, without impinging on the maxillary sinus or inferior alveolar canal.

Exclusion Criteria:

* Obvious exclusions are patients who do not meet all the inclusion criteria or who will not cooperate with the follow-up schedule.
* Patients will not be entered who are mentally incompetent, prisoners, or pregnant.
* Pregnant women or women intending to become pregnant during the study period. As standard practice prior to dental surgery, females of child-bearing age are asked verbally if there is any possibility that they are pregnant. If not, we proceed with surgery and no pregnancy test is done. If the woman states that there is a possibility that she is pregnant, we do a urine pregnancy test to rule pregnancy in or out. So use of the urine pregnancy test is only done if she says she may be pregnant. \[If needed: An over-the-counter urine pregnancy test will be provided to female subjects in the graduate periodontics clinic of UTHSCSA. Patients will be allowed access to a private restroom and the results of the tests will be read by one of the named investigators. Only those with a negative pre-operative pregnancy test will be eligible for the study.\] Female patients who have undergone a hysterectomy, tubal ligation or menopause will be excluded from pregnancy testing.
* Patients who become pregnant during the study will be withdrawn and standard care will be delivered.
* Clinical and/or radiographic determinations which will preclude inclusion in this study are:

  * Active localized or systemic infection other than periodontitis.
  * Untreated periodontal diseases
  * Inadequate bone dimensions or restorative space dimensions to place a dental implant
  * Presence of a disease entity, medical condition or therapeutic regimen which decreases probability of soft tissue and bony healing, e.g., poorly controlled diabetes, chemotherapeutic and immunosuppressive agents, or autoimmune diseases.
  * Positive medical history of endocarditis following oral or dental surgery.
D: Inclusion Criteria:

* Systemically healthy subjects with 1 maxillary premolar tooth requiring extraction
* Residual extraction sockets must have \< 80% bone loss in all dimensions (3 or 4-walled bony defects)
* Nonsmokers (individuals who quit smoking at least 6 months prior to the study will be allowed to participate)
* Subjects willing and able to comply with all study-related procedures including maintenance of good oral hygiene and compliance with re-evaluation appointments
* Subjects who read, understand and are willing to sign an informed consent statement

Exclusion Criteria:

* Inadequate zone of keratinized gingiva (KG) or alveolar mucosa to obtain primary wound closure of the surgical site
* Presence of acute infections at the time of tooth extraction
* Clinically significant or unstable (as defined by the investigators) systemic diseases affecting bone or soft tissue growth or other renal, hepatic, cardiac, endocrine, hematological, autoimmune or acute infectious diseases that makes interpretation of the data more difficult
* History of head \& neck radiation therapy
* Subjects taking steroids, tetracycline or tetracycline analogs, bone therapeutic levels of fluorides, biphosphonatesm, medications affecting bone turnover, antibiotics for \> 7 days or any investigational drug
* Patients who are or become pregnant during the length of the study
* Sites in which one or both adjacent teeth are missing

Answer: B