Prospective, Comparative Volumetric Assessment of Alveolar Ridge Preservation Utilizing Different Bone Grafting Materials (SYMBIOS CORTICAL-CANCELLOUS GRANULE MIX; SYMBIOS OSTEOGRAF LD-300; OSTEOGRAF/N-300) Following Tooth Extraction
Phase: NA
Conditions: Tooth Fractures, Tooth Injuries, Tooth Diseases
Sponsor: University of North Carolina, Chapel Hill

 
PROSPECTIVE, COMPARATIVE ASSESSMENT OF ALVEOLAR RIDGE 
PRESERVATION USING DIFFERENT BONE GRAFTING MATERIALS 
(SYMBIOS CORTICAL-CANCELLOUS GRANULE MIX; SYMBIOS 
OSTEOGRAF LD-300; OSTEOGRAF/N-300) FOLLOWING TOOTH 
EXTRACTION 
 
NCT number NCT02532543 
Document Date October 04, 2016 
 

 
 
 
CLINICAL STUDY PROTOCOL 
 
 
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PROSPECTIVE, COMPARATIVE ASSESSMENT OF 
ALVEOLAR 
RIDGE 
PRESERVATION 
USING 
DIFFERENT 
BONE 
GRAFTING 
MATERIALS 
(SYMBIOS CORTICAL-CANCELLOUS GRANULE 
MIX; 
SYMBIOS 
OSTEOGRAF 
LD-300; 
OSTEOGRAF/N-300) 
FOLLOWING 
TOOTH 
EXTRACTION 
 
 
Study Product: 
 
Study Code: 
 
 
 
Date: 
October 4, 2016 

 
 
 
 
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PROTOCOL SYNOPSIS 
 
Principal Investigator  
Jonathan Reside, DDS, MS 
 
Co-Investigators  
Ingeborg De Kok, DDS, MS 
David Semeniuk, BDSc 
Anthony Prudenti, DDS 
 
Study Coordinator 
Gidgetta Jenkins 
 
Study center(s) and number of subjects planned 
The study will include a total of 80 subjects recruited at the University of North 
Carolina, USA 
 
Study timetable 
 
Estimated date of first subject 
enrolled 
Q4 2015 
Estimated date of last subject 
completed 
 
Q3 2016 
Objectives 
The primary objective of this study is to investigate volumetric osseous changes of 
an extraction socket at 3 months following a ridge preservation procedure using 
three different commercially available grafting materials (allograft, xenograft, and 
alloplast). 
 
Secondary objectives include calculating linear horizontal and vertical bone and soft 
tissue changes. 
 
Study design 
The study is designed as a randomized controlled clinical trial.  Immediately following 
tooth extraction, patients will be assigned to one of four treatment groups for ridge 
preservation.  Groups will include the following:  
• Group A (Symbios demineralized cortical-cancellous granule mix, Symbios 
OsteoShield Collagen Resorbable Membrane) (Allograft) 
• Group B (Symbios OsteoGraf/LD-300, Symbios OsteoShield Collagen 
Resorbable Membrane) (Alloplast) 
• Group C (OsteoGraf/N-300,Symbios OsteoShield Collagen Resorbable 
Membrane) (Xenograft) 
• Group D (Symbios OsteoShield Collagen Resorbable Membrane only) 
 

 
 
 
 
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Target subject population 
Patients in need of extraction and ridge preservation within zones 4-13, 20-22, and 
27-29 will be included. 
 
Investigational products 
All products are intended to be used in an on-label procedure.   
 
Symbios demineralized cortical-cancellous granule mix is an allograft bone graft 
material. 
 
Symbios OsteoGraf LD-300 is an alloplastic bone grafting material composed of a 
low density synthetic hydroxyapatite. 
 
OsteoGraf/N-300 is a xenoplastic bone grafting material that is a bovine-derived 
microporous hydroxyapatite. 
 
Symbios OsteoShield Collagen Resorbable Membrane is a resorbable tissue matrix 
composed of Type-I Bovine collagen taken from the Achilles tendon. It presents as a 
multi-layer membrane which guides the healing of bone and the surrounding tissue, 
while the inner layers help prevent cellular and bacterial down growth into the site of 
bone preservation. 
 
Duration of treatment 
The study will be a 3 month follow-up.  The treatment period includes tooth 
extraction followed by a ridge preservation procedure.  Follow-up visits following the 
ridge preservation will occur at 14 days, and 3 months. 
 
Outcome variables 
Efficacy 
Primary outcome variable:  
- 
Volumetric osseous dimensional changes at 3 months 
Secondary outcome variables:  
- 
Horizontal and vertical dimensional changes in site (CBCT, cast 
measurements) 
- 
Soft tissue dimensional changes (CBCT, cast measurements) 
Patient reported outcomes 
- 
Not applicable 
Health economics 
- 
Not applicable 
Pharmacokinetics 
- 
Not applicable 

 
 
 
 
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Safety 
- 
Not applicable 
Genetics 
- 
Not applicable 
 
Statistical methods 
All primary and secondary outcome measurements will be analyzed by Wilcoxon 
rank sum test. 
 

 
 
 
 
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1 INTRODUCTION 
1.1 Background 
 
Following tooth extraction, a reduction in the alveolar ridge dimension occurs as a 
consequence of the wound healing process (1, 2).  These resorptive changes 
preferentially affect the buccal bone, resulting in a horizontal shift of the bone volume 
to the lingual (3).  Studies indicate that osseous resorption of 29-63% of the initial 
horizontal ridge width may occur, with much of the remodeling occurring within the 
first 3 months following extraction (2).  When implant replacement is planned, this 
reduction in bone width and the displacement of the ridge crest may challenge ideal 
dental implant, resulting in the need for further bone augmentation procedures at 
time of implant placement and/or compromised implant positioning. 
 
Implant positioning must facilitate esthetics and functional restoration.  As such, 
maintenance of the alveolar architecture is desirable, although not detrimental, in 
helping to achieve this proper implant positioning.  Attempts to prevent the 
dimensional ridge alterations associated with extraction socket healing have resulted 
in the development of ridge preservation procedures, whereby membranes are 
placed over the extraction socket and/or regenerative biomaterials are placed within 
the extraction socket, in an effort to maintain the alveolar ridge.  While an implant 
can still be placed in an extraction site that has not undergone a ridge preservation 
procedure, systematic reviews suggest that ridge preservation techniques can be 
used to reduce the amount of horizontal and vertical ridge changes following tooth 
extraction (4, 5), possibly reducing the need for additional bone grafting procedures, 
and facilitating ideal implant placement.  Currently ridge preservation procedures are 
not regarded as the standard of care. The majority of ridge preservation evidence, is 
restricted to linear measurements on radiographs or dental casts, which may not 
take into account volumetric or dimensional hard and soft tissue changes. 
 
Membranes and bone replacement grafts are commonly used in ridge preservation 
procedures.  A variety of bone graft options are available, including autogenic, 
allogenic, xenogenic, and alloplastic options, none of which have shown any 
superiority over another.  The use of autogenic bone, however, requires a second 
surgical site, leading to increased treatment time and added patient 
morbidity.  Instead, allografts, xenografts, and alloplasts are favored for ridge 
preservation procedures due to their convenience.  Similarly, allogenic, xenogeneic, 
and alloplastic membranes have been used to seal extraction sockets, promoting a 
more ideal healing pattern, and reducing the amount of bone loss (6). What is 
unclear, however, is the effect of these different grafting materials in maintaining the 
ridge.  Clarification of their unique influences, if any, of the maintenance of the post-
extraction alveolus is necessary to help guide treatment decisions. 
1.2 Rationale 
This study is intended to provide statistically robust evidence that Symbios 
demineralized Cortical cancellous mix, Symbios OsteoGraf LD-300, and 
OsteoGraf/N-300 combined with Symbios OsteoShield Collagen Resorbable 
Membrane can adequately support the alveolus during ridge augmentation 

 
 
 
 
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procedures, reducing the dimensional changes of both the alveolus and the overlying 
soft tissues. Additionally, a comparison between each material will be made, 
providing further evidence of each materials’ ability to preserve the alveolus. An 
additional comparison of the use of the Symbios OsteoShield Collagen Reservable 
Membrane with or without supportive graft material will be made. These comparisons 
are intended to define in objective terms the response of the hard and soft tissues to 
ridge augmentation using four different protocols currently used in clinical practice. 
To fulfill the goals of this project, the clinical study will enroll sufficient patients to 
perform statistical analyses of primary objectives. 
 
A common and non invasive approach used for site assessment following a grafting 
procedure is the use of cone-beam computed tomography (CBCT) images 
(7).  Several studies have demonstrated the reproducibility and accuracy of CBCT(8-
11); concluding that there was no significant difference between the radiographic and 
clinical measurements.  CBCT is now acknowledged by the American Academy of 
Oral and Maxillofacial Radiology, for the pre-surgical implant planning and 
augmentation procedures as the imaging modality of choice for preoperative cross-
sectional images of potential implant sites (12). CBCT may be used to measure the 
alveolar bone condition prior to implant therapy and following ridge 
preservation.  Therefore, when serial CBCT data is available, the direct volumetric 
assessment of ridge preservation outcomes will be possible.  
 
 
 

 
 
 
 
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2 STUDY OBJECTIVES 
2.1 Primary objective 
The primary objective is to compare the volumetric changes in the osseous 
dimensions following a post-extraction ridge preservation procedure.  Three different 
bone-grafting materials will be used, along with comparison to a non-grafted 
membrane only group.  Data will primarily be obtained from DICOM images acquired 
by CBCT imaging.  A surface based model will be constructed through image 
segmentation from both the pre- and post-operative CBCT images. The models will 
then be aligned/superimposed using a surface registration algorithm. Both images 
will be cropped to represent the same region of interest and the volumes will be 
calculated and compared. 
 
Hypothesis: No significant differences in ridge volume maintenance are anticipated 
among the three grafting groups. The combined use of particulate graft material with 
a resorbable collagen membrane will maintain a greater ridge volume than the use of 
a resorbable collagen membrane alone. 
 
2.2 Secondary objectives 
Secondary objectives of the study are to evaluate and compare: 
• Buccolingual dimensional changes in site (CBCT) 
• Vertical dimensional changes in site (CBCT) 
• Soft tissue contour changes associated with healing post extraction (digitized 
cast measurements superimposed on CBCT images) 
 
 

 
 
 
 
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3 STUDY PLAN AND PROCEDURES 
3.1 Overall study design and flow chart 
The study is designed as a randomized controlled prospective clinical trial. 
 
The study population will consist of individuals requiring an extraction with socket 
preservation.  Sites within zones 4-13, 20-22, 27-29 will be included.  
 
80 subjects will be included. Each subject will be randomized into one of three bone 
graft treatment groups or one membrane only treatment group:  
• Group A (Symbios demineralized cortical-cancellous granule mix, Symbios 
OsteoShield Collagen Resorbable Membrane) (Allograft) 
• Group B (Symbios OsteoGraf/LD-300, Symbios OsteoShield Collagen 
Resorbable Membrane) (Alloplast) 
• Group C (OsteoGraf/N-300,Symbios OsteoShield Collagen Resorbable 
Membrane) (Xenograft) 
• Group D (Symbios OsteoShield Collagen Resorbable Membrane only) 
 
The study will be a 3 month follow-up with 4 clinic visits. 
 
Figure 1 Study flow chart 
 

 
 
 
 
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3.1.1  Visit 1:  Screening 
 
Subjects in need of a single tooth extraction and ridge preservation of a single tooth 
bound by adjacent teeth that are deemed eligible by meeting inclusion and exclusion 
criteria will be considered for treatment in this study.  The tooth requiring extraction 
must lie within the region 4-13, 20-22, 27-29 (maxillary or mandibular first premolar 
or anterior tooth, excluding mandibular incisors). 
 
Before any assessment or examination is carried out  the subject must have been 
informed orally and in writing about the study, and have signed the appropriate 
clinical and study consent forms.  Informed consent for the research study will be 
given and signed on paper, as well as HIPAA authorization. Subjects will also be 
asked to sign informed consent documents. 
 
Individuals meeting all inclusion and exclusion criteria and that have signed all 
appropriate consent forms will be further evaluated.  A clinical exam will entail 
evaluation of general dental and systemic health.  It will also include a clinical and 
radiographic assessment of the tooth to be removed and the adjacent teeth, which is 
standard of care.  Pre-existing radiographs (e.g. panoramic and intraoral) can be 
used but must not be older than 6 months.  An impression will be made using an 
elastomeric impression material of the planned extraction site to allow fabrication of 
a temporary tooth (standard clinical requirement). This impression will also serve an 
additional research purpose, providing baseline tissue data. Subjects will 
immediately be scheduled for Visit 2 provided that they fulfill all inclusion and 
exclusion criterion. 
 
A radiographic stent for research purposes will be fabricated using the model 
obtained from the initial impression to aid in image alignment, superimposition and 
identifying the points of measurement for the study objectives. 
 
After pre-surgical evaluation and planning, patients will be enrolled and randomly 
allocated treatment into treatment group A, B, or C; or into group D. 
 
This visit includes all procedures, which are standard clinical protocol, with additional 
usage of the clinical impression for research purposes. 
 
3.1.2 Visit 2: Extraction, Initial CBCT, and Socket Preservation Surgery 
Randomization and Stratification 
Subjects meeting all inclusion and none of the exclusion criteria will be randomly 
allocated to group A, B, C, or D, through the blind drawing out of a folded piece of 
paper containing the assigned treatment group (20 pieces indicating group, A, B, C 
and D) by the PI or co-investigators. Subjects will be randomized into treatment 
groups immediately following tooth extraction. 
 

 
 
 
 
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Figure 2 Randomization and stratification 
 
 
 
 
 
 
Pre-Surgical, Surgical, and Post-Surgical Care (at surgical appointment) 
Pre-surgical, surgical and post-surgical care will be given at the discretion of the 
Investigator and recorded in appropriate sections in the CRF: 
• Antibiotics 
• Analgesics 
• Anaesthesia 
• Anxiolysis 
 
Antibiotics: 
Pre-surgical antibiotic prophylaxis will be provided for patients at risk for infective 
endocarditis or with total joint replacement according to current guidelines provided 
by the American Dental Association, American Heart Association (13), and the 
American Academy of Orthopaedic Surgeons (14). 
 
Post-surgical antibiotic coverage will be provided to patients.  It is anticipated that a 
7-day course of 500mg Amoxicillin every 8 hours or 300mg Clindamycin every 6 
hours will be provided. 
 
Analgesics: 
Post-surgical analgesics will be provided, most likely consisting of 800mg Ibuprofen 
every 6-8 hours and 5/325mg Acetaminophen/Hydrocodone every 4-8 hours. 
 
Anxiolysis: 
Options will be discussed with the patient and a decision will be made to reduced 
anxiety using 1-2mg Ativan. 
 
Anesthesia: 
20% benzocaine topical anesthesia will be maintained for 1 minute.  Infiltration 
anesthesia using 2% lidocaine with 1:100,000 and 2% lidocaine with 1:50,000 
epinephrine will be provided.  It is anticipated that 1.8 to 3.6cc will be used. 
 
Post-surgery, infiltration anesthesia with 0.5% bupivacaine with 1:200,000 will be 
provided.  It is anticipated that 1.8cc will be used. 
 

 
 
 
 
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All medications used are standard clinical practices. 
 
Pre-Surgical Procedures 
Buccal and crestal photographs of the planned surgical site will be obtained using a 
Canon 50D digital camera body with a Canon 100mm f/2.8 macro lens and a Canon 
MR-14EX macro ring flash. 
 
All pre-surgical procedures including photographs taken are standard clinical 
practice in the School of Dentistry clinics. 
 
Surgical Procedure 
A circumferential sulcular incision will be placed around the teeth to be extracted.  
Periotomes and luxators will be used to extract the tooth with minimal trauma to the 
adjacent tissues. The socket wall will be examined for any dehiscence greater than 
3mm or fenestrations. If these are present, the patient will be excluded from the 
study. Gauze will be placed in the area to produce wound hemostasis 
 
Immediately following tooth extraction, the patient will have a small field-of-view cone 
beam computed tomography (CBCT) image produced whilst wearing the 
radiographic stent.  Images will provide pre-preservation data for horizontal and 
vertical bone locations. 
 
Following CBCT imaging, a ridge preservation procedure will be completed as 
follows: 
• Group A:  Symbios demineralized cortical-cancellous granule mix 
reconstituted in sterile saline will be used to augment the socket and will be 
covered by a Symbios OsteoShield Collagen resorbable membrane. 
• Group B: Symbios OsteoGraf LD-300 reconstituted in sterile saline will be 
used to augment the socket and will be covered by a Symbios OsteoShield 
Collagen resorbable membrane. 
• Group C:  Symbios OsteoGraf/N-300 reconstituted in sterile saline will be 
used to augment the socket and will be covered by a Symbios OsteoShield 
Collagen resorbable membrane  
• Group D: Socket covered with Symbios OsteoShield Collagen resorbable 
membrane and no grafting material, allowing socket to heal. 
 
Grafted sockets will be closed with a barrier membrane using 5-0 chromic gut suture.  
It is anticipated that a cross mattress and/or simple loop sutures will be employed. 
 
All surgical procedures listed above are standard clinical procedures, including 
preparation and utilization of grafting materials list above. 
 
Post-Surgical Procedures 
Buccal and crestal photographs of the surgical site will be obtained, which is 
standard clinical practice in the School of Dentistry. 
Standard UNC post-operative instructions will be given which includes the use of a 
Chlorhexidine rinse 2 times daily for 2 weeks. 
 
This visit includes a CBCT for research purposes only. The remainder of treatment is 
standard clinical protocol. 

 
 
 
 
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3.1.3 Visit 3:  Post-Operative Visit (14 days ± 2 days) 
The stage of healing will be clinically assessed.  Remaining suture material will be 
removed.  Buccal and crestal photographs of the surgical site will be obtained using 
a Canon 50D digital camera body with a Canon 100mm f/2.8 macro lens and a 
Canon MR-14EX macro ring flash. 
 
AEs/ADEs will be recorded. 
 
This visit is standard clinical protocol 
 
3.1.4 Visit 4: Cone Beam Computed Tomography Imaging (12 weeks ± 
7 days) 
Small field-of-view cone beam computed tomography (CBCT) imaging whilst wearing 
the radiographic stent will be obtained for all patients 3 months following surgical 
treatment.  Images will provide post-ridge preservation data for horizontal and 
vertical bone assessments.  Buccal and crestal photographs of the surgical site will 
be obtained. An elastomeric impression of the site will be obtained. 
 
AEs/ ADEs will be recorded. 
 
This appointment contains a CBCT, photographs and an impression which is 
standard clinical protocol when planning future implant placement. Additionally the 
CBCT and impression will be used for research purposes. 
 
Additional visits may be scheduled at the discretion of the investigator and recorded 
as extra visits in the CRF. 
 
Figure 3 Appointment flow chart 

 
 
 
 
 
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Table 1  Study plan 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
**All standard of care procedures will be used for research purposes. 
 
Standard of Care Clinical requirement=C 
Research requirement =R 
Visit Number 
1 
2 
3 
4 
Visit Description 
Screening, 
Impressions 
Extraction, 
initial CBCT, 
Ridge 
Preservation 
Post-op 
Post-op, 
Impressions, 
final CBCT 
Visit Window 
 
0 
2w 
12w 
Patient Information 
 
 
 
 
Informed consent 
X (R) 
 
 
 
Patient demographics 
X (C) 
 
 
 
Medical/surgical history 
X, (C) 
 
 
 
Oral examination 
X (C) 
 
 
 
Inclusion/exclusion criteria 
X (R) 
 
 
 
Radiographic examination 
X (C) 
 
 
 
Treatment 
 
 
 
 
CBCT 
 
X (R) 
 
X (C) 
Clinical photography 
 
X (C) 
X (C)  
X (C) 
Tooth Extraction 
 
X (C) 
 
 
Site Preservation 
 
X (C) 
 
 
Suture removal 
 
 
X (C)  
 
Impression 
X (C) 
 
 
X (C) 
Other 
 
 
 
 
Adverse events/Adverse device effects 
 
X  
X 
X 
Summary of additional patient 
requirements per appointment solely 
for research purposes 
 
CBCT 
 
 

 
 
 
 
 
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3.2 Rationale and risk/benefit assessment  
Limited data is available regarding volumetric changes of the alveolus following tooth 
extraction and ridge preservation procedures.  This has direct effects on subsequent 
dental implant treatment.  Successful ridge preservation enhances proper implant 
placement.  Furthermore, it is necessary to better define the effects of different 
grafting materials on the clinical outcomes following ridge preservation.  This study 
has been designed to treat a clinical scenario commonly encountered in clinical 
practice 
 
The public will benefit from the study results, which will help to define the knowledge 
of bone healing following extraction and ridge preservation with different grafting 
materials.  This will help aid clinicians in the selection of materials to optimize their 
clinical outcomes of treatment.  It will also further characterize the effects of these 
materials on soft tissue healing while comparing its outcomes to other commonly 
used materials.  Data acquisition includes minimally invasive collection methods, 
both before and after the extraction and ridge preservation procedure.  
 
3.2.1 Study selection record 
Investigator(s) will keep a record of subjects who were considered for enrollment but 
were never enrolled (e.g., subject screening log).  This information is necessary to 
establish that the subject population was selected without bias. 
3.2.2 Inclusion criteria 
For inclusion in the study subjects must fulfill all of the following criteria: 
 
1. 
Provision of informed consent 
2. 
≥ 18 years and ≤ 75 years 
3. 
Good physical health (ASAI/II) 
4. 
Extraction of maxillary premolar, canine or incisor, or mandibular premolar and 
canine required (4-13, 20-22, 27-29) 
5. 
Teeth adjacent (mesial and distal) to study site must consist of two stable 
natural teeth with minimal restorations, without signs of periodontal bone loss (> 
3 mm) and/or significant soft tissue deficiencies 
3.2.3 Exclusion criteria 
Any of the following is regarded as a criterion for exclusion from the study: 
 
1. 
Buccal plate dehiscence and/or fenestration >3mm at study site following 
extraction 
2. 
Untreated rampant caries and uncontrolled periodontal disease 
3. 
Inadequate oral hygiene (estimated plaque score >20%) 

 
 
 
 
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4. 
Smokers using more than 10 cigarettes or equivalent per day 
5. 
Smokeless tobacco use or e-cigarette use 
6. 
Compromised physical health and/or uncontrolled or severe systemic diseases 
including: 
ASA III/IV 
Metabolic bone disease 
History of malignancy 
History or radiotherapy or chemotherapy for malignancy in the past 5 
years 
History of autoimmune disease 
Long-term steroidal (20mg cortisol or equivalent for 2 weeks duration in 
past 2 years) or antibiotic therapy (Antibiotic therapy exceeding 2 weeks in 
past 1 year) 
 
Uncontrolled diabetes (HbA1c ≥7) 
 
Known alcohol or drug abuse 
7. 
Systemic or local disease or condition that would compromise post-operative 
healing 
8. 
Use of any substance or medication that will influence bone metabolism 
9. 
Pregnancy at time of screening 
10. Unable or unwilling to return for follow-up visits for a period of 3 months 
11. Unlikely to be able to comply with study procedures according to Investigators 
judgement 
12. Involvement in the planning and conduct of the study 
13. Previous enrolment or randomization of treatment in the present study 
3.2.4 Restrictions 
Subjects will be advised of the following restrictions during the study period: 
• To avoid disruption of wound healing during the initial study period the subject 
should have a restricted diet for at least 3-5 days and will be instructed to 
avoid manual oral hygiene in site for 2 weeks (printed instructions will be 
distributed to the subjects at Visit 2) 
• For current smokers, interim cessation will be encouraged and no more than 
10 cigarettes per day are allowed 

 
 
 
 
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3.2.5 Discontinuation of subjects from treatment or assessment 
3.2.5.1 Criteria for discontinuation 
Subjects may be discontinued from study treatment and assessments at any time. 
Specific reasons for discontinuing a subject from this study are: 
 
• Voluntary discontinuation by the subject who is at any time free to discontinue 
his/her participation in the study, without prejudice to further treatment 
• Safety reasons as judged by the investigator  
• Severe non-compliance to protocol as judged by the investigator 
• Incorrect enrolment (i.e., the subject does not meet the required 
inclusion/exclusion criteria for the study) 
• Subject received further dental therapy on study site or adjacent teeth without 
consent of investigator (e.g. new crown, periodontal surgery, or orthodontics 
on adjacent teeth) 
• Subject lost to follow-up 
3.2.5.2 Procedures for discontinuation 
Subjects who discontinue should always be asked about the reason(s) for their 
discontinuation and the presence of any AEs or ADEs.  If possible, they should be 
seen and assessed by an investigator(s).  Ongoing AEs and ADEs should be 
followed up. 
 
A subject will be classified as lost to follow up only if, he/she has failed to return to 
the required study visits and his/her dental status remains unknown, despite multiple 
attempts to contact the subject via telephone, fax, email, certified letter and through 
subject locator agencies (if allowed per national regulation). 
3.3 Treatments 
3.3.1 Identity of investigational product and comparators 
All procedures involved in this research study are standard of care procedures for 
patients requiring dental extraction and desiring dental implant treatment in the 
future. All graft materials and their combinations used in this study are widely used in 
the dental procession for patient care. All components are commercially available. 
 
Symbios demineralized cortical-cancellous granule mix is a human allograft product 
obtained from the Musculoskeletal Transplant Foundation (MTF), which mimics the 
natural bone anatomy, providing space maintenance and surface area for bone 
formation. The material contains 80% cortical and 20% cancellous bone, displaying a 
particle size of 200-1000 microns. 
 
Symbios OsteoGraf LD-300 is a 100% pure synthetic hydroxyapatite bone product 
that shows 56% porosity and high surface area. It is conducive to solution-mediated 
resorption, producing a readily available source of calcium for bone regeneration. 
This low density resorbable grafting material presents as 250-420 micron particles, 
and is available in 0.5, 1.0 and 3.0 gram vials. 

 
 
 
 
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Symbios OsteoGraf/N – 300 is a sintered natural anorganic bovine-derived 
microporous hydroxyapatite, displaying a particle size of 250-420 microns. The 
hydroxyapatite is conducive to cell-mediated resorption and provides a scaffold for 
new bone growth, holding the space until host bone takes over. There are no 
extractable proteins present in the product. The product is available in 1.0 and 3.0 
gram vials. 
 
Symbios OsteoShield Collagen Resorbable membrane made from Type-I bovine 
collagen from the Achilles tendon. It has a resorption time of between 26 and 38 
weeks. It is a multi-layered membrane, which assists in healing of the bone and 
surrounding tissues, while the inner layers help prevent cellular and bacterial down 
growth. The membrane is available in 15x20mm, 20x30mm and 30x40mm. 
3.3.2 Labeling 
All grafting materials and membranes will be labelled as follows: 
• “Reference number” 
• “Lot number” 
• “Expiration date” 
 
The reference number and lot numbers will be recorded in clinical records (source 
data) and CRF. 
3.3.3 Storage 
All investigational products must be kept in a secure place under appropriate storage 
conditions.  A description of the appropriate storage and shipment conditions are 
specified on the study product label and product information. 
3.3.4 Accountability 
Distributed study products will be used for this study in accordance with the Clinical 
Study Protocol.  All product deliveries will be confirmed by the investigator or 
delegate.   
3.4 Method of assigning subjects to treatment groups 
Subject numbers (subject ID) will be consecutively allocated in series at day of 
inclusion (Visit 1).  Subjects will receive numbers starting at 101.  Enrollment will 
continue until 80 subjects have been allocated a subject ID.  If a subject 
discontinues, the subject number will not be reused. 
 
Subjects will be randomized strictly sequentially at day of extraction and ridge 
preservation (Visit 2).  At Visit 2 all study sites in all subjects are considered 
equivalent.  The randomization schedule will be generated using a validated system 
under the responsibility of the investigatory team.  80 pieces of folded paper will 
contain the allocated treatment group (20 each of group A, B, C and D) and 
contained in an enclosed container. One piece of paper will be blindly selected by 
the PI or co-investigators, and the treatment group will be revealed to the clinician 
only following extraction of the tooth. 

 
 
 
 
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The randomization code papers will be stored in an enclosed and concealed 
container and stored by PI and co-investigators. 
 
3.5 Pre-study, concomitant and post-study treatment(s) 
In the case of dehiscence, fenestration, infection, or other surgical complications 
encountered during treatment and/or healing, appropriate site preservation 
procedures and/or debridement and/or infection control steps will be implemented. 

 
 
 
 
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4 MEASUREMENTS OF STUDY VARIABLES AND 
DEFINITIONS OF OUTCOME VARIABLES 
4.1 Screening and demographic measurements 
The following data will be recorded via a standard CRF: 
• Date of birth 
• Height and weight (Body Mass Index) 
• Sex 
• Race 
• Relevant medical and surgical history 
• Medication 
• Oral examination  
• Local condition of alveolus and adjacent teeth 
o Periodontal disease 
o Bone loss 
o Caries 
o Mobility 
o Crown 
o Post/core 
o Endodontic treatment 
o Existing periapical radiolucency 
• Tobacco use 
• Reason for tooth extraction 
• Previous bone graft, soft tissue graft, or apical surgery 
4.2 Efficacy 
4.2.1 Primary outcome variable 
4.2.1.1 Volumetric osseous changes 
The amount of change in bone volume will be calculated using data from DICOM 
images acquired by CBCT using 3D software. 
4.2.1.1.1 Methods of assessment 
CBCT images will be obtained at baseline (Visit 2) and 3 months 
following alveolar ridge augmentation (Visit 4).  Using 3D imaging 
software, the bone will be segmented to produce an STL file. Following 
this, the segmented images will be superimposed and aligned through 
a fiducial point registration algorithm, and at the same time, the same 
region of interest will be cropped in each scan and exported as a 
separate model. The volume of the baseline and 3 month scan will be 
calculated and compared.  
4.2.1.1.2 Derivation or calculation of variable 

 
 
 
 
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The changes in the bone volume between baseline (Visit 2) and 3 
months (Visit 4) will be measured electronically using 3D analysis 
software. The change for each study site will be compared 
longitudinally and the average for each treatment group will be 
calculated and compared among treatment and control groups. 
 
 
4.2.2 Secondary Outcome Variables 
4.2.2.1 Osseous dimensional changes 
The amount of horizontal and vertical bone changes will be calculated using data 
from DICOM images acquired by CBCT using 3D software. 
4.2.2.1.1 Methods of assessment 
CBCT images will be obtained at baseline (Visit 2) and 3 months 
following alveolar ridge augmentation (Visit 4).  Using 3D analysis 
software, the CBCT images will be aligned via superimposition through 
fiducial point registration, to permit evaluation of bone changes within 
the bound edentulous space. 
4.2.2.1.2 Derivation or calculation of variable 
The mid-alveolar point (middle of the extraction site) positioned on a 
tangent drawn from the mesial and distal adjacent tooth CEJs will be 
used as a reference point for assessment of dimensional bone 
changes in the Z-axis (Bone width) at 3, 6 and 9mm as measured from 
the height of the original buccal zenith (with the aid of a radiographic 
stent. Measurements will be taken from at these points from the buccal 
plate to the lingual plate. Changes in the Y-axis (bone height) will also 
be assessed.  The changes in the bone dimensions between baseline 
(Visit 2) and 3 months (Visit 4) will be measured.  The change for each 
study site will be compared longitudinally and the average for each 
treatment group will be calculated and compared among treatment 
groups. 
 
 
4.2.2.2 Soft tissue dimensional change 
The amount of soft tissue change will be assessed through the use of dental casts at 
two time points following extraction and ridge preservation, and 3 months. 
4.2.2.2.1 Methods of assessment 
Elastomeric impressions will be made of the site at baseline, and 3 
months following extraction. The impression will be poured in dental 
stone, and the cast will be scanned using an optical/laser scanner to 
produce a digitized model. The digital models will then be aligned in 3D 
software and superimposed on one another and the relevant CBCT 
image utilizing the fiducial point registration algorithm. 
4.2.2.2.2 Derivation or calculation of variable 

 
 
 
 
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The mid-alveolar point (middle of the extraction site) positioned on a 
tangent drawn from the mesial and distal adjacent tooth CEJs will be 
used as a reference point for assessment of dimensional bone 
changes in the Z-axis (soft tissue width) at 3, 6 and 9mm as measured 
from the height of the original buccal zenith and indicated on the 
radiographic stent. Measurements will be taken from at these points 
from the buccal contour to the underlying buccal plate. Changes in the 
Y-axis (soft tissue height) will also be assessed.  The changes in the 
soft tissue dimensions between baseline (Visit 2) and 3 months (Visit 4) 
will be measured. The change for each study site will be compared 
longitudinally and the average for each treatment group will be 
calculated and compared among treatment groups. 
 
4.3 Patient reported outcomes 
Not applicable 
4.4 Health economic measurements and variables 
Not applicable 
4.5 Pharmacokinetics 
Not applicable 
4.6 Safety measurements and variables 
The methods for collecting safety data are described below. 
4.6.1 Adverse Events 
4.6.1.1 Definitions 
The definitions of AEs, ADEs and Serious Adverse Events (SAEs) are given below.  
It is of the utmost importance that all staff involved in the study are familiar with the 
content of this section.  The principal investigator is responsible for ensuring this. 
Adverse Event 
An AE is any untoward and unintended medical occurrence in a subject.  This 
definition does not imply that there is a relationship between the AE and the medical 
device under investigation.  An AE which is possibly related, is one that may have 
been caused by the medical device, or treatment, however there is insufficient 
information to determine the likelihood of this possibility.   
• Possibly related: temporal relationship of the onset of the event, relative to the 
use/administration of the medical device, is reasonable but the event could 
have been due to another, equally likely cause.  
• Non-related (unlikely): temporal relationship of the onset of the event, relative 
to the use/administration of the medical device, is not reasonable or another 
cause can itself explain the occurrence of the event. 
Ambiguous cases should be considered as possibly related. 

 
 
 
 
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Adverse Device Effect 
An ADE is any untoward and unintended response to a medical device.  This 
definition includes any event resulting from insufficiencies or inadequacies in the 
instructions for use of the medical device or any event that is a result of a user error.  
This definition also includes treatment- or procedure-related events. ADEs can only 
occur from the time of medical device use/administration.  Here the event is related 
to the use of the medical device where there is a probable/definite relationship that 
the event may have been caused by the medical device, or treatment.  
• Probably related: temporal relationship of the onset of the event, relative to 
the use/administration of the medical device, is reasonable and the event is 
more likely explained by the medical device/treatment than by any other 
cause.  
• Definitely related: temporal relationship of the onset of the event, relative to 
the use/administration of the medical device, is reasonable and there is no 
other cause to explain the event. 
Serious Adverse Event 
A SAE is an AE/ADE occurring during any study phase of the medical device that 
fulfills one or more of the following criteria: 
• Results in death 
• Is immediately life-threatening 
• Requires in-subject hospitalization or prolongation of existing hospitalization 
• Results in persistent or significant disability or incapacity 
• Is a congenital abnormality or birth defect 
• Is an important medical event that may jeopardize the subject or may require 
medical intervention to prevent one of the outcomes listed above 
If a non-related AE becomes serious, i.e. fulfilling one or more of the above criteria, 
action should be taken as for any other SAE. 
4.6.1.2 Recording of Adverse Events and Adverse Device Effects 
At each visit, scheduled or unscheduled, the subject will be asked an open question; 
"Have you had any health problems since the previous visit?"  
 
All health problems, reported by the subject or found at the clinic visit, where the 
investigator believes the event "possibly" has been caused by the investigational 
medical device or treatment, must be recorded in the CRF as AEs, specifying time of 
onset, action taken, outcome and whether it constitutes a SAE or not.  Non-related 
AEs must be recorded in the CRF together with a short description and whether it 
constitutes a SAE or not. 
 
All health problems, reported by the subject or found at the clinic visit, where the 
investigator believes the event "probably/definitely" has been caused by the 
investigational medical device or treatment, must be recorded in the CRF as AEs 
and ADEs, specifying time of onset, action taken, outcome and whether it constitutes 
a SAE or not. 
 
Should a pregnancy occur, it must be reported in accordance with the procedures 
described in Section 9.2, Pregnancy.  Pregnancy in itself is not regarded as an AE 

 
 
 
 
23(32) 
unless there is a suspicion that a medical device under study may have interfered 
with the effectiveness of a contraceptive medication. 
4.6.1.3 Reporting of Serious Adverse Events 
Timelines for reporting of SAEs 
Investigators and other study site personnel must inform the ethics committee and, if 
necessary, the appropriate regulatory authorities of any SAE that occurs during the 
course of the study within the timeline set by the code of federal regulations. 
 
4.7 Genetics 
Not applicable 
 
 

 
 
 
 
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5 DATA MANAGEMENT 
5.1 Data handling 
A web-based electronic data capture system (REDCAP) will be used. The eCRF will 
be completed for each included patient.  The completed eCRFs will not be made 
available in any form to third parties without written permission from the principal 
investigator/sponsor.  
 
All data from source documents will be entered into the eCRF database.  The data 
entry will be verified by means of double data entry or proofreading.  Before 
database lock, both manual and computerized validation tests will be performed and, 
if necessary, data queries will be sent to the investigator for clarification.  Should 
questionable data be detected during the validation process, written queries will be 
raised as result of this validation.  The study site personnel are required to resolve 
any such queries.  The eCRFs will be retained for 3 years following completion of the 
study as required by law and then disposed of according to the standard operating 
procedure of the School of Dentistry for patient information. 
 
5.2 Record retention 
To enable evaluations and/or audits from regulatory agencies, the investigator 
agrees to keep records in the Investigator’s Study File (ISF), including the 
identification list of the participating patients, all original signed Informed Consent 
forms, and detailed records of medical device disposition.  To comply with 
international regulations, the investigator should retain the records for 3 years 
following completion of the study as required by law and then disposed of according 
to the standard operating procedure of the School of Dentistry for patient information. 
 
 

 
 
 
 
25(32) 
6 STATISTICAL METHODS AND DETERMINATION OF 
SAMPLE SIZE 
6.1 Statistical evaluation – general aspects 
A comprehensive Statistical Analysis Plan (SAP) may be prepared before database 
lock. If prepared, the SAP will be kept as an appendix to the Data Management Plan. 
When using the terminology descriptive statistics it means that number of patients, 
mean, median, standard deviation, minimum and maximum values will be presented 
for continuous data and frequencies and percentages for categorical data. 
 
Descriptive statistics will be given for each variable in the study and p-values may be 
complemented by confidence intervals as appropriate.  A p-value less than 0.05 will 
be considered “statistically significant”. 
6.1.1 Demographics and other baseline characteristics 
Demographics and other baseline characteristics will be presented by means of 
descriptive statistics (by group and in total).  Continuous variables will be presented 
by means of number of observations (N), minimum (min), median, maximum (max), 
mean, and standard deviation (SD).  Discrete variables will be presented by 
frequency and percentage. Difference in patient demographics between the 
treatment groups will be assessed using the Chi Square test to assess the similarity 
in treatment groups, ensuring that the outcomes are not influenced by difference in 
treatment group demographics. 
6.1.2 Covariates and prognostic variables 
No covariates are judged to influence the outcome of the primary or any of the 
secondary variables, however these will be assessed using the Chi Square test. 
6.1.3 Handling of dropouts and missing data 
Patients dropping out from the trial prior to study end will not be replaced.  Data 
totally missing will not be estimated. 
6.1.4 Subgroup analyses 
No subgroup analyses are planned. 
6.2  Method of statistical analysis 
6.2.1 Primary objective 
The primary objective is to compare dimensional bone changes from baseline (Visit 
2) to three months (Visit 4) occurring in a single bound extraction site following ridge 
preservation using three different grafting materials and membrane, and one no graft 
membrane only group.  
 
Assume the change is denoted CA, CB, CC , and CD, for group A, B, C, and D 
respectively. The null-hypothesis is then to test if: 

 
 
 
 
26(32) 
H0 CA = Ci (i = B, C, and D respectively)  
can be rejected and hence 
H1 CA ≠ Ci (i = B, C, and D respectively)  
accepted. 
  
H0 will be tested by means of the Wilcoxon rank sum test. A p-value less than 0.05 
will be regarded statistically significant. 
6.2.2 Secondary objectives 
Both the dimensional soft tissue changes from baseline (Visit 2) to three months 
(Visit 4) and linear soft tissue and osseous changes occurring in a single bound 
extraction site following ridge preservation using three different materials will be 
compared.  
 
Assume the change (in the mid-buccal horizontal soft tissue dimensions from 
baseline to three months) is denoted CA, CB, CC , and CD, for group A, B, C, and D 
respectively. The null-hypothesis is then to test if: 
H0 CA = Ci (i = B, C, and D respectively)  
can be rejected and hence 
H1 CA ≠ Ci (i = B, C, and D respectively)  
accepted. 
  
H0 will be tested by means of the Wilcoxon rank sum test. A p-value less than 0.05 
will be regarded statistically significant. 
 
6.3 Determination of sample size 
A sample size of 20 participants per treatment group was selected following power 
calculations and allowing for 10% patient dropout (has dropout rate been factored 
into our sample size of 20 patients per group).  A sample size of 18 patients was 
calculated for the primary outcome variable (horizontal bone changes) with the 
assumption that the detectable difference would amount to 0.5mm3 with a standard 
deviation of 0.5.  The type I error probability was set at 0.05 and the statistical power 
was set at 80%. 
6.4 Statistical analyses during the course of the study 
The primary and secondary objectives will be analyzed when all data from the 3 
month follow-up visit has been collected, entered, verified, and validated (partial 
clean file).  
 
 

 
 
 
 
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7 STUDY MANAGEMENT 
7.1 Audits and Inspections 
Authorized regulatory authorities or an ethics committee may visit the center to 
perform audits or inspections, including source data verification. The purpose of an 
audit or inspections is to systematically and independently examine all study-related 
activities and documents to determine whether these activities were conducted, and 
data were recorded, analyzed, and accurately reported according to the protocol, 
ISO 14155, Good Clinical Practice (GCP), guidelines of the International Conference 
on Harmonization (ICH), and any applicable regulatory requirements. 
7.2 Training of staff 
The principal investigator will maintain a record of all individuals involved in the study 
(medical, nursing and other staff).  He or she will ensure that appropriate training 
relevant to the study is given to all of these staff, and that any new information of 
relevance to the performance of this study is forwarded to the staff involved. 
7.3 Changes to the protocol 
Study procedures will not be changed without the agreement of the principal 
investigator. 
 
If it is necessary for the study protocol to be amended, the amendment and/or a new 
version of the study protocol (Amended Protocol) must be notified to or approved by 
each Ethics Committee, and if applicable, also the local regulatory authority, before 
implementation.  Local requirements must be followed. 
 
If a protocol amendment requires a change to Informed Consent Form, then the 
Ethics Committee must be notified. Approval of the revised Informed Consent Form 
by the Ethics Committee is required before the revised form is used.   
7.4 Study timetable 
Before a subject's enrollment in the study and any study-related procedures are 
undertaken the following should be fulfilled: 
• Approval of the clinical study protocol 
• Approval of the study by the Ethics Committee 
• Approval of the study, if applicable, by the regulatory authority 
 
 

 
 
 
 
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8 ETHICS 
8.1 Ethics review 
The final study protocol, including the final version of the Informed Consent Form, 
must be approved or given a favorable opinion in writing by an Ethics Committee as 
appropriate.   
 
The Principal Investigator is responsible for informing the Ethics Committee of any 
amendment to the protocol in accordance with local requirements.  In addition, the 
Ethics Committee must approve all advertising used to recruit subjects for the study. 
 
The Principal Investigator is also responsible for providing the Ethics Committee with 
reports of any SAEs (or ADEs) from any other study conducted with the 
investigational product.   
 
Progress reports and notifications of SAEs (and ADEs) will be provided to the Ethics 
Committee according to local regulations and guidelines. 
8.2 Ethical conduct of the study 
The study will be performed in accordance with ethical principles that have their 
origin in the Declaration of Helsinki and are consistent with ISO 14155 and 
ICH/Good Clinical Practice and applicable regulatory requirements. 
8.3 Informed consent 
The principal investigator(s) will ensure that the subject is given full and adequate 
oral and written information about the nature, purpose, possible risk and benefit of 
the study.  Subjects must also be notified that they are free to discontinue from the 
study at any time.  The subject should be given the opportunity to ask questions and 
allowed time to consider the information provided. 
 
The subject’s signed and dated informed consent must be obtained before 
conducting any procedure specifically for the study.  The principal investigator(s) 
must store the original, signed Informed Consent Form in the ISF.  A copy of the 
signed Informed Consent Form must be given to the subject. 
8.4 Subject data protection 
The Master Informed Consent Form will incorporate (or, in some cases, be 
accompanied by a separate document incorporating) wording that complies with 
relevant data protection and privacy legislation.  Pursuant to this wording, subjects 
will authorize the collection, use and disclosure of their study data by the Investigator 
and by those persons who need that information for the purposes of the study. 
 
The Master Informed Consent Form will explain that study data will be stored in a 
computer database, maintaining confidentiality in accordance with national data 
legislation.  
 
 

 
 
 
 
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9 PROCEDURES IN CASE OF EMERGENCY 
9.1 Medical emergency 
In the case of a medical emergency you may contact the Clinical Study Team 
Leader.  If the Clinical Study Team Leader is not available, contact the Study 
Coordinator, see below:  
 
Role in the study 
Name 
Address & telephone number 
Principal Investigator 
Jonathan Reside, DDS, 
MS 
UNC School of Dentistry 
111 Brauer Hall 
CB #7450 
Chapel Hill, NC  27599-7450 
 
Tel: (919) 537-3727 
Study Coordinator 
Gidget Jenkins 
UNC School of Dentistry 
9.1.1.1.1 School of Dentistry 
9.1.1.1.2 UNC Chapel Hill 
9.1.1.1.3 Prosthodontics  
9.1.1.1.4 CB #7450 
Chapel Hill, NC 27599-7450 
Tel: 919-537-3968 
 
The principal investigator(s) is responsible for ensuring that procedures and 
expertise are available to handle medical emergencies during the study.  A medical 
emergency usually constitutes an SAE and should be reported as such. 
9.2 Pregnancy 
Many physiologic changes can be observed in the pregnant patient and should be 
considered when planning dental treatment. It has been suggested to avoid elective 
dental procedures in the 1st and 3rd trimesters due to risk of spontaneous abortions, 
pre-term births, increased patient discomfort, and increased likelihood of 
intraoperative complications (15).  The ultimate goal in dental therapy during 
pregnancy should be to educate the patient on the importance of oral hygiene and 
plaque control, perform periodontal maintenance therapy and treat emergency 
situations. 
 
According the American College of Obstetricians and Gynecologists, fetal risks of 
anomalies, growth restriction, or abortions are not increased with radiation 
exposures of less than 5 rad (50,000mSv), a level which is well above the range of 
exposure for diagnostic purposes (16). CBCT radiation exposure levels depends on 
field of view and manufacturer, and has been shown to fall within the range of 69 to 
560 mSv when a medium field of view CBCT was used (17). These dosages are well 

 
 
 
 
30(32) 
below the deterministic threshold for fetal abnormalities as outlined above. Despite 
the very low risk of adverse pregnancy outcomes, adherence to the ALARA principle 
or radiology will be adhered to. 
 
Although pregnancy is not a specific exclusion criteria for the study, all potential 
female subjects of reproductive age will be asked to complete a urine pregnancy test 
prior to enrollment in the study. Patients who are pregnant at the time of screening 
will be excluded from the study and referred back to their primary dental provider for 
further dental treatment. Patients who become pregnant during the course of the 
study will be asked to notify study personal. As the initial research indicated CBCT 
would have been completed prior to the patient knowing they were pregnant, and the 
second CBCT is a standard clinical requirement prior to implant placement, the 
patient will not be placed at any additional risk if they remained in the study, than if 
they were not taking part in the study. The patient does have the right to withdraw 
themselves from the study. Patients will be appropriately educated about the 
possible effects of dental treatment during pregnancy, along with the effects of 
ionizing radiation exposure as outlined below.  
 
Pregnancy itself is not regarded as an AE/ADE unless there is a suspicion that the 
medical device under study may have interfered with the effectiveness of a 
contraceptive medication.  
 
Congenital abnormalities/birth defects and spontaneous miscarriages should be 
reported as SAEs.  Elective abortions without complications should not be handled 
as AEs/ADEs. 
 
 

 
 
 
 
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10 REFERENCES 
1.         Schropp L, Wenzel A, Kostopoulos L, Karring T. Bone healing and soft tissue 
contour changes following single-tooth extraction: a clinical and radiographic 12-
month prospective study. The International journal of periodontics & restorative 
dentistry 2003;23:313-323. 
2.         Tan WL, Wong Tl Fau - Wong MCM, Wong Mc Fau - Lang NP, Lang NP. A 
systematic review of post-extractional alveolar hard and soft tissue dimensional 
changes in humans. 
3.         Araujo MG, Lindhe J. Dimensional ridge alterations following tooth extraction. 
An experimental study in the dog. 
4.         Ten Heggeler JM, Slot DE, Van der Weijden GA. Effect of socket 
preservation therapies following tooth extraction in non-molar regions in humans: a 
systematic review. Clinical oral implants research 2011;22:779-788. 
5.         Darby I, Chen ST, Buser D. Ridge preservation techniques for implant 
therapy. Int J Oral Maxillofac Implants 2009;24 Suppl:260-271. 
6. Vittorini Orgeas G, Clementini M, De Risi V, de Sanctis M. Surgical techniques for 
alveolar socket preservation: a systematic review. Int J Oral Maxillofac Implants. 
2013;28(4):1049-61 
7.         Fienitz T, Schwarz F, Ritter L, Dreiseidler T, Becker J, Rothamel D. Accuracy 
of cone beam computed tomography in assessing peri-implant bone defect 
regeneration: a histologically controlled study in dogs. Clinical oral implants research 
2012;23:882-887. 
8.         Veyre-Goulet S, Fortin T, Thierry A. Accuracy of linear measurement 
provided by cone beam computed tomography to assess bone quantity in the 
posterior maxilla: a human cadaver study. Clinical implant dentistry and related 
research 2008;10:226-230. 
9.         Kim TS, Caruso JM, Christensen H, Torabinejad M. A comparison of cone-
beam computed tomography and direct measurement in the examination of the 
mandibular canal and adjacent structures. Journal of endodontics 2010;36:1191-
1194. 
10.         Pertl L, Gashi-Cenkoglu B, Reichmann J, Jakse N, Pertl C. Preoperative 
assessment of the mandibular canal in implant surgery: comparison of rotational 
panoramic radiography (OPG), computed tomography (CT) and cone beam 
computed tomography (CBCT) for preoperative assessment in implant surgery. 
European journal of oral implantology 2013;6:73-80. 
11.       Ganguly R, Ruprecht A, Vincent S, Hellstein J, Timmons S, Qian F. Accuracy 
of linear measurement in the Galileos cone beam computed tomography under 
simulated clinical conditions. Dento maxillo facial radiology 2011;40:299-305. 
 
12.       Tyndall DA, Price JB, Tetradis S, Ganz SD, Hildebolt C, Scarfe WC, et al. 
Position statement of the American Academy of Oral and Maxillofacial Radiology on 
selection criteria for the use of radiology in dental implantology with emphasis on 
cone beam computed tomography. Oral Surg Oral Med Oral Pathol Oral Radiol 
2012;113:817-826. 
 
13. Wilson W, Taubert KA, Gewitz M, Lockhart PB, Baddour LM, Levison M, et al. 
Prevention of infective endocarditis: guidelines from the American Heart Association: 
a guideline from the American Heart Association Rheumatic Fever, Endocarditis and 
Kawasaki Disease Committee, Council on Cardiovascular Disease in the Young, and 

 
 
 
 
32(32) 
the Council on Clinical Cardiology, Council on Cardiovascular Surgery and 
Anesthesia, and the Quality of Care and Outcomes Research Interdisciplinary 
Working Group. J Am Dent Assoc. 2008;139 Suppl:3S-24S. 
 
14. Watters W, 3rd, Rethman MP, Hanson NB, Abt E, Anderson PA, Carroll KC, et 
al. Prevention of Orthopaedic Implant Infection in Patients Undergoing Dental 
Procedures. J Am Acad Orthop Surg 2013;21:180-189 
 
15. KurienS, Kattimani VS, Sriram R, Sriram SK, Prabhakar Rao VK, Bhupathi A, 
Bodduru R, Patil NN. (2013) Management of Pregnant Patient in Dentistry. Journal 
of International Oral Health. 5, 88-97. 
 
16. Guidelines for diagnostic imaging during pregnancy. ACOG Committee Opinion 
No. 299. American College of Obstetricians and Gynecologists. Obstet Gynecol 
2004; 104:647-51 
 
17. Ludlow JB, Ivanovic M. Comparative dosimetry of dental CBCT devices and 64-
slice CT for oral and maxillofacial radiology. Oral Surg Oral Med Oral Pathol Oral 
Radiol Endod. 2008;106(1):106-14.