Short Dental Implants (5 mm) Versus Long Dental Implants (10 mm) in Combination With Sinus Floor Elevation: A Randomized Clinical Trial
Phase: NA
Conditions: Bone Loss, Alveolar
Sponsor: University of Michigan

 
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Cover Page for ClinicalTrials.gov 
 
 
 
Document: 
Protocol 
 
 
Official Study Title: 
Short dental implants (5 mm) versus Long dental implants (10 mm) in combination 
with sinus floor elevation: A Randomized Clinical Trial 
 
 
NCT Number: 
NCT04144322 
 
 
Document Date: 
December 6, 2022 
 

 
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Short dental implants (5 mm) versus Long dental 
implants (10 mm) in combination with sinus floor 
elevation: A Randomized Clinical Trial 
 
University of Michigan School of Dentistry 
Department of Periodontics and Oral Medicine 
 
 
 
 
 
In partial fulfillment of the M.S. in Periodontics  
 
 
 
 
 
 
 
Candidate:  
Andrea Ravidà, DDS, MS  
Resident, Graduate Periodontics 
 
 
Thesis Committee:  
                                                                                Tae-Ju Oh, DDS, MS (PI) 
Jordi Gargallo-Albiol, DDS, MS, PhD 
                                                                                                   Furat M. George, DDS (Co-I) 
Junying Li, DDS, MS, PhD (Co-I) 
Hom-Lay Wang, DDS, MSD, PhD (Co-I) 
                                                                                                   Shan-Huey Yu, DDS, MS (Co-I) 
 
 
Study Coordinator: 
Alice Ou, RDH, MS 
 
 
 
Version 3.3 

 
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INTRODUCTION 
 
List of Abbreviations: 
Implant placement (IP) 
Marginal Bone level changes (MBL) 
Probing pocket depth (PPD) 
Bleeding on Probing (BOP) 
Group Short (GS): Experimental Group 
Group Long (GL): Control Group 
 
 
BACKGROUND and SIGNIFICANCE 
 
Edentulism is a condition of being toothless, which impacts the patient’s ability in performing some 
daily tasks and affects their esthetic appearance and self-confidence (Misch, 2007). Prostheses 
supported by dental implants can improve patients’ quality of life by providing a pleasant appearance 
as well as comfort in speaking and chewing (Sargozaie et al., 2017). After extraction, the bony socket 
undergoes significant horizontal and vertical resorption especially in the maxillary posterior area 
(Chappuis et al., 2017). These changes often lead to more complex and time-consuming procedures, 
such as a lateral or transcrestal sinus lift, for placing implants in the area.  Despite the reliability of 
these techniques, providers are faced with challenges such as elevated cost, higher morbidity, and 
more intra- and post-surgical complications. These challenges may be overcome by utilizing less 
invasive procedures such as short implants. However, the definition of a short dental implant remains 
a topic of controversy. According to Striezel & Reichart, an implant with a length of ≤11 mm is 
considered short (Strietzel and Reichart, 2007) whereas some authors consider a short implant to be 
<10 mm (Mezzomo et al., 2014, Telleman et al., 2014) or <8 mm (Fan et al., 2017). Additionally, an 
implant with a length of ≤6.5 mm has been defined as extra-short (Anitua et al., 2014, Anitua et al., 
2015) . During the last decade, short implants have shown to be a reliable and effective alternative 
solution for patients with bone atrophies (Pieri et al., 2017). Indeed, it has been demonstrated that 
unfavorable crown to implant (C/I) ratio is not related to increased biological complications or 
implant failure (Garaicoa-Pazmino et al., 2014). However, prevalence of peri-implantitis could 
present a greater concern due to the limited length, especially for people with previous history of 
periodontitis. A recent meta-analysis on short implants versus standard implants in the posterior jaw 
that included 13 studies with 1269 patients and 2631 implants showed no significant difference in 
implant survival, marginal bone loss, complications, or prosthesis failure. Nevertheless, it was 

 
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concluded that short implants with <8 mm should be used with caution because they present a higher 
risk of failure as compared to standard-length (≥8mm) implants (Lemos et al., 2016). In a systematic 
review based on the evaluation of 8 randomized controlled clinical trials (RCTs), the European 
Academy of Osseointegration (EAO) Consensus Conference in 2015 noted that longer dental 
implants in the augmented sinus caused a higher number of biological complications, increased 
morbidity, costs and surgical time. Therefore, shorter dental implants may be the preferred treatment 
alternative (Thoma et al., 2015). A recent multicenter, randomized, controlled clinical trial found that 
short implants (6 mm) for single-tooth restorations in the posterior maxilla were a viable solution 
versus longer implants (≥10mm) in combination with sinus lift. After three years of follow-up and 
with a residual ridge height of 5–7 mm, no implants were lost in both groups and no statistically 
significant difference in prosthetic complications were reported (Pohl et al., 2017). All these studies 
excluded patients with a previous history of periodontitis. 
 
 
OBJECTIVES OF THE STUDY 
 
The purpose of this study is to evaluate clinical and radiological parameters of 5 mm short implants 
(GS) compared to longer implants (GL) (10 mm) placed in sinus-grafted sites. 
 
Null Hypothesis (H0): There are no statistically significant clinical or radiographic outcome 
differences between the two groups, GS and GL.  
Alternative Hypothesis (H1): There are statistically significant clinical or radiographic outcome 
differences between the two groups, GS and GL. 
 
 
STUDY DESIGN 
 
The present study will be a parallel, randomized single center clinical trial performed according to 
the CONSORT statement (http://www.consort-statement.org/). 
Two different treatment modalities, GS and GL, will be compared in this randomized clinical trial. 
GS subjects will receive a short dental implant (5 mm in length) with no sinus lift whereas GL 
subjects will receive a 10 mm long implant after sinus lifting with allograft. The flow chart of the 
study is presented in Fig. 1. 
 

 
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Fig. 1 CONSORT flow chart of the study
 
 
The Institutional Review Board (IRB) for the Medical Sciences at the University of Michigan, Ann 
Arbor, MI, must review and approve this study before enrollment of participants begins. It is the 
responsibility of the investigator to assure that all aspects of the institutional review are conducted in 
accordance with current Federal Regulations.  A letter with IRB approval for the protocol must be 
received by the Principal Investigator before the initiation of the study. Amendments to the protocol 
will be subject to the same requirements as the original protocol.  At each annual protocol renewal, 
an updated report of the numbers of samples and any adverse events will be provided to the IRB.  
After completion or termination of the study, the investigator will submit a final report to the IRB.  
This report should include any deviations from the protocol, the number of patients evaluated, 
adverse events, and a conclusion summarizing the results. This study will also be registered on 
ClinicalTrials.gov. In addition, the study will be conducted according to the principles outlined in 
the Declaration of Helsinki on experimentation involving human subjects, as revised in 2000. 
Partially edentulous patients requiring an implant to replace a missing tooth in the maxillary premolar, 
1st molar, or 2nd molar area with bone crest height more than 5 mm but less than 8 mm will be 
recruited for this trial. Up to 50 patients will be enrolled (half randomized for each group) in the 
Periodontics and Oral Medicine clinic at the University of Michigan School of Dentistry, Ann Arbor, 
Michigan.  

 
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A signed, written informed consent must be obtained from each subject before he or she enters the 
study after he or she has been given verbal and written information describing the nature and duration 
of the study. Subjects will be consented in a private cubicle inside the Periodontics and Oral Medicine 
clinic. An investigator or study coordinator will give the consent document to the potential subject 
and answer any questions the subject has before and after they read the consent document. Subjects 
will be given ample time to read the form and ask questions before they sign. The signed informed 
consent will be retained with the study records.  Each subject will also be given a copy of his/her 
informed consent. 
Patients that meet the inclusion/exclusion criteria and consent to the research study will receive a 
dental implant at no cost and an implant crown at reduced cost to replace their missing tooth. Research 
subjects will be followed for 24 months (± 1 month) after implant placement, for a total of 23-26 
months (see Appendix A: Schedule of Events) for the entire study. Subjects will complete 10 research 
visits as described in the Study Procedures. 
Primary and secondary endpoints 
Primary endpoint: Comparing mesial-distal (M-D) bone loss between the two groups (Radiologic 
outcome) 
Secondary endpoints: Clinical outcomes and Patient reporting outcomes 
1. Determine the survival rate and success rate of the Group Short (GS) and Group Long (GL) 
group. 
2. Compare incidence and types of surgical and prosthetic complications between groups 
3. Compare the number of sites with bleeding on probing (BOP)  
4. Compare the cost of both procedures and the cost of the prosthetic complications 
5. Compare the probing pocket depth (PPD) 
6. Determine the pain after treatment: Visual analog score (VAS)  
7. Compare patient satisfaction 
8. Compare surgical time 
Participants 
50 patients satisfying the following inclusion criteria will be recruited: 
 Age 20 years or older at enrollment 
 Able to provide informed consent 
 Systemically healthy patients 

 
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 Full-mouth plaque score and full-mouth bleeding score ≤ 30% (measured at four sites per 
tooth) 
 Missing one premolar, 1st molar, or 2nd molar in the maxillary arch (Minimum healing time 
after extraction: ≥4 months) 
 One neighboring tooth or implant restoration must be present to the implant site. 
 Presence of natural tooth/teeth, partial prosthesis and/or implants in the opposite jaw in 
contact with the planned crown/s deemed by the investigator as likely to present an initially 
stable implant situation 
 Residual bone height under the maxillary sinus more than 5 mm but less than 8 mm and a 
width of at least 7 mm, as measured on cone beam computer tomography (CBCT) scans. 
 
Exclusion criteria are: 
 Unlikely to be able to comply with study procedures 
 Uncontrolled pathologic processes in the oral cavity 
 History of allergic reactions to dental local anesthetics 
 History of head and neck chemotherapy or radiation within 5 years prior to surgery 
 Systemic or local disease or condition that could compromise post-operative healing and/or 
osseointegration, such as HIV infection, Paget’s disease, osteoporosis, etc. 
 Uncontrolled diabetes mellitus (HbA1c >8) 
 Patients taking corticosteroids, IV bisphosphonates, or any other medication that could 
influence post-operative healing and/or osseointegration 
 Smokes more than 10 cigarettes/day 
 Present alcohol and/or drug abuser (self-reported) 
 Pregnant, unsure pregnancy status, or lactating females (self-reported), or planning to become 
pregnant within 1 year of study enrollment 
 Any medical conditions that may affect the outcome of the study. 
 
INVESTIGATIONAL PRODUCT OVERVIEW 
Implants 
 GS - T3 Short External Hex with DCD 5.0 mm Length Implants; Zimmer Biomet (Zimmer, 
Palm Beach Gardens, Florida, US)  
 GL - T3 with DCD External Hex Parallel Walled x 10 mm Length Implants; Zimmer Biomet 
(Zimmer, Palm Beach Gardens, Florida, US) 

 
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STUDY PROCEDURES 
Clinical measurements 
1) The following measurements will be taken for each treated implant by a blinded, calibrated 
examiner at the implant placement (surgery V2), at the time of prosthetic placement (5-month post-
op V6), 12-month follow-up (V8), and 24-month follow-up (V10). 
  Marginal bone level (MBL): It will be calculated based on standardized radiographs using 
registered bite-block with a Rinn (Dentsply Rinn, Elgin, IL, USA) film holder and expressed 
as the distance from the implant shoulder to the most coronal bone-to-implant contact (BIC) 
on the mesial and distal side of the implant. The mean values will be calculated for each 
implant at the time of implant placement, at the time of prosthetic placement (5-month post-
op V6), 12-month follow-up (V8), and at 24-month follow-up (V10). In the case that the 
bone levels around the study implants are hidden or difficult to read, new radiographs will 
be taken. Peri-implant marginal bone levels will be measured using the ImageJ software* 
(ImageJ, U. S. National Institutes of Health, Bethesda, Maryland, USA) (Schneider et al., 
2012). The software will be calibrated for every single image using the known implant 
length or the length of the implant collar. Measurements of the mesial and distal bone crest 
level adjacent to each implant will be rounded to the nearest 0.1 mm. Implants with bone up 
to the coronal margin of the implant collar will be given a value of zero. Mesial and distal 
measurements of each implant are averaged, and a mean calculated at patient level and then 
at group level.  
 PPD and BOP: It will be assessed at 4 sites per implant (mesial, distal, buccal, and palatal) 
with a measurement stent using a periodontal probe (UNC, Hu-Friedy, Chicago, IL, USA). 
PPD are measured from the distance of the mucosal margin to the bottom of the probable 
pocket in mm. BOP is recorded using the following scoring method: 0) no bleeding 1) an 
isolated bleeding spot is visible, 2) blood forms a confluent red line on margin, and 3) heavy 
or profuse bleeding. 
 Plaque: The level of oral hygiene will be evaluated using the Modified gingival index (Lobene 
et al., 1986) (Scores 1-4).  
0 = Absence of inflammation 
1 = Mild inflammation or with slight changes in color and texture but not in all portions of 
gingival marginal or papillary 
2 = Mild inflammation, such as the preceding criteria, in all portions of gingival marginal or 
papillary 

 
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3 = Moderate, bright surface inflammation, erythema, edema and/or hypertrophy of gingival 
marginal or papillary 
4 = Severe inflammation: erythema, edema and/or marginal gingival hypertrophy of the unit 
or spontaneous bleeding, papillary, congestion or ulceration. 
 Prosthesis failure: Planned prosthesis which could not be placed due to implant failure(s), 
loss of the prosthesis secondary to implant failure(s), or replacement of the definitive 
prosthesis for any reason.  
 Implant failure: It will be defined as implant mobility (assessed from force applied with two 
hand instrument), pain, or neuropathy.  
 Implant success: It will be defined as 1) Absence of persistent subjective complaints such as 
pain, foreign body sensation and/or dysesthesia 2) Absence of a peri-implant infection with 
suppuration 3) Absence of mobility 4) Absence of a continuous radiolucency around the 
implant and 5) Absence of any biological or prosthetic complications (Buser et al., 2012)  
 Peri-implantitis: It will be defined as detectable radiographic bone loss beyond the initial 
biological bone remodeling. 
2) The following measurements will be taken for each treated implant by a blinded, calibrated 
examiner after implant placement, 12-month follow-up, and 24-month follow-up.  
 Bone thickness (BT): It will be determined based on CBCT and expressed as the distance 
from the most coronal bone-implant contact to the outer surface of the buccal plate. The 
mean values will be calculated for each implant.  
3) The following measurements will be taken for each treated implant by a blinded, calibrated 
examiner at prosthetic placement, 12-month follow-up, and 24-month follow-up. 
 Crown to implant ratio: The height of the crowns will be measured on the radiographs from 
the implant-abutment interface to the most coronal point on the crown. The anatomical 
crown-to-implant ratio (anatomical C/I ratio) will then be calculated dividing the anatomical 
crown by the length of the implant.4) 
 
4)  ISQ (Implant stability quotiant) will be measured at the time of healing abutment placement. 
Intra-operatory measurements  
 Subjective evaluation of the bone type (Lekholm & Zarb 1985) during implant site 
preparation will be performed by the surgeon.  
- 
Type 1: Almost entirely comprised of homogeneous compact bone 

 
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- 
Type 2: thick layer of compact bone surrounding a core of dense trabecular bone 
- 
Type 3: thin layer of cortical bone surrounding a core of dense trabecular bone 
- 
Type 4: Thin layer of cortical bone surrounding a core of low-density trabecular bone 
coupled with the surgeon’s tactile perception 
 Thickness of soft tissues will be measured with a 1.0-mm marked periodontal probe (UNC, 
Hu-Friedy, Chicago, IL, USA) on the top of bone crest in the center of future implant 
placement. This will ensure direct visibility of mucosal thickness during measurement. 
 Patient phenotype: Classification of the patient’s phenotype will be thin, medium, thick, or 
very thick by using the Colorvue biotype probe (Hu-Friedy). 
 Chair time of the surgical procedure will be recorded from the end of local anesthesia until 
the completion of sutures. 
 The time required for placement of one single implant, with both treatments (short implants 
and sinus floor elevation with placement of longer implants) will be calculated as follows: 
the time required for the entire surgical procedure (from anesthesia to sutures) will be 
assessed for each patient and divided by the number of installed fixtures. The ratio of the 
time required for placement of a single short implant to the time required for a sinus floor 
elevation procedure in combination with a longer implant will be calculated and expressed 
as a percentage.  
 A wireless magnetic-based Osstell Mentor RF Analyzer (Ostell USA, Linthicum, MD, USA) 
will be used to assess primary implant stability. The designated transducer (SmartPeg) will 
be hand-tightened per the manufacturer’s instructions to the fixture. ISQ values will be taken 
immediately after implant placement and measured in triplicate and averaged to yield the 
mean baseline ISQ value for each implant.  
Clinical measurement to monitor early healing 
 At the 2-week post-op suture removal visit (± 2 days after surgery) clinical photographs will 
be taken. In addition, data on soft tissue complications (edema, bleeding), general 
discomfort, pain (measured by VAS from 0 to 100) (Appendix A) and patient satisfaction 
(Appendix B) will also be collected at the 2-week post-op visit.  
 
Demographic data and patient questionnaires  
At the pre-surgical visit, age, gender, smoking habits (number of cigarettes/day) will be recorded.  
At the 2-week post-op visit, data on post-operative pain during the first day and possible side 

 
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effects or complications of the first three days will be registered. Patient discomfort will be 
measured by VAS scale and number of post-operative pain medication quantified. Patients will 
receive 3 sheets containing the VAS scale to be filled out daily. In case of drop out, the related 
reason will be registered (Appendix B).  
Furthermore, all patients will be asked at the 2-weeks, 12-month, and 24-month follow-up to give 
their perception of the received therapy by completing a questionnaire concerning function, 
esthetics, cleaning of the implant-supported restorations, satisfaction, and cost (Appendix C).  
Screening & Pre-surgical procedures 
The medical history and vitals (heart rate and blood pressure) will be taken. In addition, clinical 
photographs and one standardized periapical radiograph will be completed. A CBCT scan will be 
taken before implant placement for screening eligibility, and impressions will be taken for surgical 
guide preparation. The CBCT scan may be scheduled separately due to availability of the CBCT 
machine. 
 
Randomization and masking of examiners 
The randomization of the patients to either the test (5-mm implant) or control group (10-mm implant) 
is determined using a computer-generated randomization list (www.random.org). After 
administration of a local like 2% Lidocaine with 1:100k epinephrine, sulcular incisions at the adjacent 
teeth and a midcrestal incision will be performed, allowing reflection of a full-thickness flap. At this 
stage, the randomization concealment will be broken, and the surgical site will be prepared according 
to the manufacturer’s instructions. 
 
Surgical procedures 
The medical history and vitals (heart rate and blood pressure) will be taken prior to the surgical 
procedure. In addition, clinical photographs will be taken during the surgical procedure. An implant 
surgical guide for partially edentulous patients will be fabricated according to procedure previously 
described by Shotwell (Shotwell et al. 2005). 
 
Experimental group (GS) 
5.0 mmL x 5.0mmD Zimmer T3 Short Ex Hex With Discrete Crystalline Deposition (DCD) 
implants: 
 
1. Crestal incision and flap elevation 

 
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2. ACT Short Pointed Started Drill will be used to penetrate the cortical bone to the first depth 
mark on the drill. The recommended drill speed is 1200-1500 rpm. Copious irrigation with 
sterile saline solution is planned to prevent overheating of the bone during high speed 
drilling. 
3. 2.0 mm ACT Short Twist Drill will be to drill to the bottom of the depth mark for 5.0 mm 
length implants. The recommended drill speed is 1250 rpm. 
4. The direction and position of the preparation is verified by inserting the narrow end of the 
direction indicator into the osteotomy. A suture will be threaded through the hole to prevent 
accidental swallowing. 
5. After proper alignment is verified using the Direction indicator, the 3.25 mm ACT Short 
Twist Drill will be used to drill until the bottom of the depth mark for 5 mm implants with a 
speed 1250 rpm. 
6. Once the coronal aspect of the osteotomy has been prepared the 3.85mm ACT Short Twist 
Drill will be used to Drill to the bottom of the depth mark for 5.0mm. The recommended 
drill speed is 1250 rpm. 
7. The 3.85 mm Short Shaping Drill with a yellow band indicating that it is for use with a 
5.0mmD T3 Short Implants. The recommended drill speed is 1250 rpm. 
8. Tapping Step for dense bone (Type I) using the Handpiece Connector advancing the tap into 
the prepared site at approximately 15-20 rpm. Final seating of the Short Dense bone Tap 
may require the use of the Ratchet Extension and the Ratchet Wrench.  
9. The implant will be placed into the prepared site at approximately 15-20 rpm. Final seating 
of the implant may require the use of a Ratchet Extension and Ratchet Wrench. 
10. To remove the implant mount, Open End Wrench will be placed onto the mount. The screw 
is loosened at the top of the mount with a Large Hex Driver or Large Hex Driver Tip 
inserted into the Right-Angle Driver or Low Torque Indicating Ratchet Wrench and rotate 
counter-clockwise. After the screw is completely loosened, the Open End Wrench will be 
rotated counter-clockwise slightly before removing the mount. The mount can be carried 
from the mouth with the Open End Wrench.  
11. Cover Screw from the No-Touch Implant Tray with the Small Hex Driver (PHD00N) is 
placed onto the implant at no more than 10 Ncm.  
12. Soft-tissue flaps will be secured and repositioned with sutures. 
13. Final periapical radiograph is taken.  
 
 

 
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Control group (GL) 
10 mmL X 5.0mmD Zimmer T3 with DCD Ex Hex Parallel Walled implants  
1. A midcrestal incision is made, with full thickness flap reflection. Then sutures will be used to 
assist flap reflection both on the buccal and palatal sides. 
2. Implant sites are marked with a 2.0mm round bur drill and prepared to a depth of 1.0 mm 
from the sinus floor with first 2 osteotome drills (up to 2.8 mm wide). 
3. 2.8 mm reamer (SCA kit, Neobiotech, Seoul, South Korea) will then be inserted with different 
stoppers until the sinus membrane wall is fractured.   
4. After the sinus membrane wall is fractured, a gauge will then be applied to check sinus wall 
surrounding to ensure membrane is lifted from the sinus wall.   
5. Subsequently, bone graft (human allograft) small particle (size 250µm to 850 µm) will be 
inserted into the osteotome sites then slowly tapped into the sinus floor either by bone 
inserter/spreader (SCA kit, Neobiotech, Seoul, South Korea) or osteotome instrument by 
mallet. These instruments should not enter the sinus cavity. 
6. The sinus floor should be elevated to at least 2 mm height longer than the desired implant 
length due to bone shrinkage occurring after healing.  
7. Implant osteotome drills will be used to drill the osteotome site to the final diameter size 
according to the manufacturer’s guideline, but only to the level of remaining bone height.  
Again, the instruments should not enter the sinus cavity to avoid any potential perforation. 
8. 10mm length of Zimmer T3 with DCD Ex Hex Parallel Walled implant will be placed into 
the prepared hole. 
9. Cover Screw is placed onto the implant at no more than 10 Ncm.  
10. Soft-tissue flaps will be secured and repositioned with sutures. 
11. Final periapical radiograph is taken.  
All surgeries will be performed under local anesthesia using one or more of the following 
medications: 
 Lidocaine with epinephrine, (Xylocaine 2%®-Epinephrine 1:100,000 and 1:50,000, 
Dentsply Pharmaceutical, York, PA, USA). 
 Articaine (Septanest 4%®-Epinephrine 1:100,000, Dentsply Pharmaceutical, York, PA, 
USA). 
 Mepivacaine (Polocaine 2%®-Levonordefrin 1:20,000, Dentsply Pharmaceutical, York, PA, 
USA).” 
 

 
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Post-surgical instructions 
All subjects will be prescribed and instructed to take the following oral antibiotics after surgery: 
500 mg amoxicillin (GlaxoSmithkline) three times per day for 7 days, or 300 mg clindamycin (if 
allergic to penicillin) four times per day for 7 days. In addition, 600 mg of ibuprofen (Brufen; 
Abbott S.R.L., Latina, Italy) as needed, and chlorhexidine mouthwashes 0.12% twice daily for 2 
weeks. Subjects with a removable prosthesis will be instructed  to not wear them during the healing 
phase. The sutures will be removed after 2 weeks. Any surgical complication will be recorded such 
as infection, pain, and other adverse events.  
 
Prosthetic placement 
After 4 months of submerged healing, exposure of the implant and placement of a healing abutment 
is performed. After  2 weeks, the sutures are removed. After 5 months of submerged healing, 
impressions via pick-up impression copings are taken either using a polyether material (Impregum 
3M/ESPE, Neuss, Germany) and/or a digital scan (TRIOS, 3Shape, Denmark). Within 1 to 3 weeks, 
definitive screw-retained metal-ceramic or metal-resin restorations are delivered.  
 
Follow-up evaluation visits  
Follow-up evaluation (2 weeks) 
 Clinical photographs 
 Suture removal 
 VAS on pain 
 Patient satisfaction 
 Implant mobility 
 Plaque index 
Follow-up evaluation (4 months) for stage 2 implant (Installment of abutment) 
 Clinical photographs 
 Standarized Periapical Radiograph 
 ISQ 
 Implant mobility 
 Plaque index 
Follow-up evaluation (4 months and 2 weeks) for post-op and impression 
 Post-op stage 2 implant, remove suture 
 Implant mobility 
 Plaque index 

 
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Follow-up evaluation (5 months) for post-op and impression 
 Impression definitive crown 
 Implant mobility 
 Plaque index 
             Follow-up evaluation (5 months and 2 weeks) for crown placement and maintenance 
 Implant maintenance 
 Definitive Crown placement 
 Clinical photographs and standardized periapical radiographs.  
 Implant mobility 
 Plaque index 
Follow-up evaluation (6 months after crown placement) 
 Clinical measurements evaluation  
 Implant maintenance 
 Clinical photographs and standardized periapical radiographs.  
 Patient satisfaction 
 Implant mobility 
 Plaque index 
Follow-up evaluation (12 months after crown placement) 
 Implant maintenance 
 Implant mobility 
 Plaque index 
Follow-up evaluation (18 months after crown placement) 
 Clinical measurements evaluation  
 Clinical photographs and standardized periapical radiographs.  
 Patient satisfaction 
 Implant maintenance 
 Implant mobility 
 Plaque index 
 
DATA MANAGEMENT 
Data reflecting participant experience with the protocol under investigation will be reported to the 
Principal Investigator and the data recorded on Case Report Forms (CRF). CRF will be signed and 

 
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dated by the investigator or a designated representative and filled out in black ink.  If an entry on a 
CRF requires change, the correction will be made as follows:   
a. A single line will be drawn through the incorrect entry. 
b. The date will be entered and the change initialed. White-out or erasure on CRFs will not be 
permitted under any circumstance.  
All fields and blanks must be completed.  The following abbreviations will be used when values or 
answers cannot be provided:  NA=not applicable; ND=not done, UNK=not known. Completed 
original CRF’s will be collected by the Principal Investigator. CRF must be submitted for each 
subject. Database entry will proceed directly from the CRF for analysis.  The data, as well as 
group/subject identification, will be made available to the investigator at the conclusion of the study.  
The study coordinator will audit all CRFs and corresponding portions of School of Dentistry records.  
The monitoring will provide the Principal Investigator the opportunity to evaluate the progress of the 
study and to verify the accuracy and completeness of the CRFs; assure that all protocol requirements, 
applicable FDA regulations and investigator’s obligations are being fulfilled, and to resolve any 
inconsistencies in the study records.  The Principal Investigator may stop the study if it is observed 
that the protocol or sound clinical practices are not being followed.  The Principal Investigator may 
exclude subjects from the study if review of their records indicates violations of the protocol or if 
there were other reasons to believe that their inclusion would jeopardize the validity of the study. 
All research records will be labeled “confidential” and kept in a locked room in a locked cabinet with 
limited access or in a password protected computer program. Only those directly involved with this 
research study will have access to the research records and password. A description of this clinical 
trial will be available on http://www.clinicaltrials.gov/, as required by U.S. Law. This Web site will 
not include information that can identify the patient. 
The study coordinator and investigator will make an accurate and adequate written progress reports 
to the IRB at appropriate intervals not exceeding one year. The investigator will make an accurate 
and adequate final report to the IRB within 3 months after completion or termination of the study. 
The investigator will make an accurate and adequate special report to the IRB on any serious 
unexpected or life-threatening adverse event or death occurring in relationship to the study whether 
regarded as study-related or not.  
On completion of the study, the investigators will prepare a final report of the study results. 
 

 
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STATISTICAL CONSIDERATIONS 
The study will be powered to detect a minimum clinically significant difference in bone loss of 0.5 
mm using α = 0.05, a power (1- β) = 80%.  Considering possible dropouts, the number of patients 
will also be increased by 10% for each arm. On the basis of this data, the minimum needed number 
of patients to be enrolled in this study is 17 with for the test group (GS) and 17 for the control group 
(GL). Mean values, standard deviations, and medians will be calculated for the clinical 
parameters. The association between crown-implant ratio and final bone loss as well as prosthetic 
complications will be examined. Changes of the parameters over time within the two groups as well 
as differences between groups will be analyzed using repeated measure of analysis of variance 
(ANOVA). 
 
 
PATIENT SAFETY AND COMPLIANCE 
 
Deviations 
The investigator will not deviate from the protocol without obtaining written approval from the IRB.  
Any other changes or deviation in the protocol will be made as an amendment to the protocol and 
must be approved by the IRB before being implemented. 
 
Risks associated with dental x-rays 
In this study, patients will have about eight standard dental x-rays and two CBCT scans. They should 
experience no more discomfort related to the x-rays than they would with x-rays taken during regular 
dental visits. The only discomfort may be related to the x-ray film or film holder pressing on the soft 
tissues.  
 
The biologic effect of radiation is termed “effective dose” (EF) and is expressed in milliSieverts 
(mSv). The amount of radiation for one dental x-ray is about 0.005 mSv and 5.3mSv for CBCT scan. 
This is considered to be a very small risk. The average radiation exposure that includes the natural 
background radiation an individual receives is about 3.1 mSv per year and about 0.008 mSv per day. 
The total amount of radiation exposure to patients from this study is minimal. 
 

 
18 
 
The researchers will try to minimize these risks by providing a lead apron that will be mandatory to 
wear during x-rays. 
 
Risk associated with surgery  
Subjects will be assigned to a treatment program by chance. The treatment they receive may prove to 
be less effective or to have more side effects than the other study treatment(s) or other available 
treatments. The likelihood that the patient will be assigned a treatment that will be less effective than 
other study treatments or other available treatments is unknown. Both surgery methods are the 
standard of care. Mild to moderate pain and swelling is expected for both groups. There is a very low 
risk of uncontrolled bleeding that may occur with subjects that are in general good health and not 
taking medications that are classified as a blood-thinner. In some cases, subjects may feel some 
temporary sensitivity with the teeth next to the implant. 
 
Implant Related Risks 
1) Implant Failure 
2) Biologic complications such as sinus membrane perforations, persistent bleeding, sinusitis (or 
acute sinus infection), rupture of sinus membrane, soft tissue (graft) dehiscence, abscess, pus, 
pain, swelling, peri-implant mucositis (heavily inflamed soft tissue without bone loss), or 
peri-implantitis (bone loss around the implant). 
3) Prosthetic complications such as fixed prosthetic device detachment, loosening of abutment 
screws or healing caps, and fracture of the screw, framework, or occlusal material. 
 
Risk of Sinus Lift 
A major risk of a sinus augmentation is that the sinus membrane could be pierced or ripped. There 
are other risks involved including infection, inflammation, hematoma, pain, graft failure, sinusitis, 
and hemorrhage. 
 
Risk of Bone Graft  
Donor bone (allograft) will be used during this study. This material has been used for more than 30 
years. Any pieces in the bone that may cause a reaction have been removed when it was made. There 
has been no report of people getting an infection from the donor bone. However, that does not mean 
an infection or reaction will not happen to the subjects. There is a low chance that the bone graft may 
get infected or the body may reject the bone graft, which would result in removal of the graft. 
 

 
19 
 
The researchers will try to minimize these risks by taking a CBCT prior to surgery. All of these risks 
are possible for any implant placed and are standard of care risks. 
 
Adverse Events (AE) 
One of the following determinations will be used to document the relationship of any adverse events 
to the study test material:  
 NOT RELATED 
 POSSIBLE 
 PROBABLE  
 
ANY SERIOUS AND UNEXPECTED ADVERSE EVENT INCLUDING HOSPITALIZATON OR 
DEATH DUE TO ANY CASE, WHICH OCCURS DURING THIS INVESTIGATION, WHETHER 
OR NOT RELATED TO THE STUDY, MUST BE REPORTED IMMEDIATELY (WITHIN 24 
HOURS) TO THE PRINCIPAL INVESTIGATOR. Reports of serious or unexpected adverse events 
will be made immediately to: Dr. Tae-Ju Oh, Phone number: (734) 647-3320 or Dr. Andrea Ravidà, 
Phone number: (734) 730-9678. 
 
This telephone report or fax must be followed within 5 days by a written summary fully documenting 
the event in order to permit the Principal Investigator to file a report, which satisfies regulatory 
guidelines. All serious and unexpected adverse events associated with the use of the study test 
material will be immediately reported to the IRB by the Principal Investigator. Adverse events 
reporting will proceed according to the University of Michigan guidelines for standard AE reporting. 
 
Withdrawing Participation 
Taking part in this study is strictly voluntary. Patients do not need to participate if they do not want 
to, and are free to leave the study at any time. In addition, their care will not be affected by not taking 
part in this study. Patients may have other options to replace their missing tooth at their own cost. 
 
The researchers may also need to end a subject’s participation in the study even if they want to 
continue to participate. For instance, a subject may be withdrawn if the researcher believes that it is 
not in their best interest to stay in the study, if they become ineligible to participate, if their condition 
changes and they need treatment that is not allowed while taking part in the study, or if the subject 
does not follow instructions from the researchers. 
 

 
20 
 
 If a subject leaves the study before it is finished, there will be no penalty to them. They will not lose 
any benefits to which they may otherwise be entitled. There would be no harm to the patient if they 
decide to leave this study before it is finished. If they leave the study before the crown is made, no 
money will be given to them and they will receive no free cleanings. 
 
 
 
 

 
21 
 
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41, 191‐213. doi:10.1111/jcpe.12180. 
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23 
 
Appendix A: Schedule of Events Table 
 
Visit 
 
Screening & Pre-
Surgical Visit 
(V1) 
 
Surgery 
(V2) 
 
2 weeks 
post-op  
(V3) 
 
4 months 
post-op  
(V4) 
 
4 months 
post-op  
(V5) 
 
5 months 
post-op  
(V6) 
 
5 months 
post-op  
(V7)  
 
6 months 
post-crown 
delivery  
(V8) 
 
12 months 
post-crown 
delivery  
(V9) 
 
18 months 
post-crown 
delivery  
(V10) 
Window 
 
Baseline 
(BL) 
± 2 days  
± 1 month  
2 weeks 
after V4 
± 2 days  
± 1 month  
± 1 month  
± 1 month  
± 1 month  
± 1 month  
Informed consent 
(*Inclusion & exclusion 
criteria) 
*X 
 
 
 
 
 
 
 
 
 
Medical History 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Adverse Events 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
CBCT scan 
(*May be scheduled 
separately) 
*X 
 
 
 
 
 
 
 
 
X 
Vitals (blood pressure 
& heart rate) 
X 
X 
 
 
 
 
 
 
 
 
Maintenance 
 
 
 
 
 
 
X 
X 
X 
X 
Implant crown 
placement (definitive) 
 
 
 
 
 
 
 
X 
 
 
 
Radiograph 
(*Standardized) 
*X 
X and *X 
 
*X 
 
 
*X 
*X 
 
*X 
Suture removal 
 
 
X 
 
X 
 
 
 
 
 
Impression 
X 
 
 
 
 
X 
 
 
 
 
Photographs 
X 
X 
X 
X 
X 
 
X 
X 
 
X 
Clinical measurement 
 
 
X 
 
X 
 
 
 
X 
X 
 
X 
Subject pain assessment 
 
 
 
X 
 
 
 
 
 
 
 
Patient satisfaction 
 
 
 
X 
 
 
 
 
X 
 
X 

 
24 
 
 
Appendix B 
 
 
Subject:________________________ 
 
 
Rating Scales for Pain Measurement 
 
 
 
Line Scale: 
 
Please rate the level of your pain by placing an “X” on the following line. 
 
No Pain                                                                                                        Worst pain imaginable 
 
 
 
 
 
 
Box Scale: 
 
Rate the level of your pain by circling one number on the scale, where 0 means “no pain” and 10 
means “worst pain imaginable.” 
 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
 
 
 
Verbal Rating Scale: 
 
Circle the phrase that best describes your pain 
 
Not Painful 
Slightly Painful 
Moderately 
Painful 
Very Painful 
Extremely Painful 
 
 
 
 
 
How much ibuprofen (or other painkiller) did you take today? ______ 
 
 
 
 
 
 
 
 
 
 
 
Survey Version 2.0 

 
25 
 
Appendix C 
 
Subject:___________________ 
 
Patient Evaluation of Implant Treatment 
Please answer the following five questions. Place an “X” on the line indicating your satisfaction from 
0 “not satisfied at all” to 100 “fully satisfied”. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1. DOES MY IMPLANT-SUPPORTED RESTORATION(S) FUNCTION 
WELL?  
Not satisfied at all 
Fully satisfied 
2. DO I FEEL SECURE BITING/CHEWING ON MY IMPLANT-
SUPPORTED RESTORATION?  
Much less secure 
Much more secure 
3. AM I PLEASED WITH THE ESTHETIC RESULT? 
Not satisfied at all 
Fully satisfied 
4. CAN I CLEAN MY IMPLANT-SUPPORTED RESTORATION(S) 
WELL? 
Extremely likely 
Extremely unlikely 
5. AM I SATISFIED WITH THE TREATMENT? 
Not satisfied at all 
Fully satisfied 

 
26 
 
 
 
6. WOULD I UNDERGO THIS TREATMENT AGAIN, IF 
REQUESTED? 
Extremely unlikely 
Extremely likely 
7. WOULD I RECOMMEND THIS TREATMENT TO A 
RELATIVE/FRIEND? 
Extremely unlikely 
Extremely likely