Retrospective Evaluation of Prosthetic Complications and Peri-implant Bone Resorption in Implant-supported Single Unit Fixed Restorations
Conditions: Implant Clinical Survival, Restoration Survival
Sponsor: Özer İşisağ

Retrospective Evaluation of Prosthetic 
Complications and Peri-implant Bone Resorption in 
Implant-Supported Single Unit Fixed Restorations 
Study Protocol 
Date: 07.04.2023 
Department of Prosthetic Dentistry 
Afyonkarahisar Health Sciences University, Faculty of Dentistry 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
Pre-assignment Details 
Participants included in the study were later excluded from the analysis due to reasons such as 
missing data in patient records, the presence of data outside the specified time frame, patients 
initially thought to meet the study criteria being incorrectly coded, or medical records being in an 
unsuitable format or unreadable. 
Arm/Group Information 
This study does not include any specific study or control groups. The research focuses on the follow-
up of participants with certain characteristics over a specified time period. 
Type of Units Assigned 
- 
Period(s): This is a retrospective study following a 12-month period. 
  Period Title: Overall Study 
  Started: This study was conducted by including patients 12 months after delivery of the 
implant-supported restoration. The sample was completed when a total of 100 patients were 
reached. 
  Completed: The number of participants at the end of the study is 100. 
Baseline Characteristics 
- 
Arm/Group Information: There were no separate groups in the study. The study included a 
12-month follow-up of participants with implant-supported single-unit restorations. 
  Arm/Group Title: There were no separate groups in the study.  
- 
Baseline Analysis Population Information 
  Overall Number of Baseline Participants: 100 participants 
- 
Baseline Measure Information 
  Baseline Measure Title 
   Age: Age, Continuous 
   Sex/Gender: Female, Male 
- 
Measure Type: Count of Participants 

- 
Measure of Dispersion: Not Applicable 
- 
Baseline Measure Data: Not Available. The study does not have any baseline data, because 
the data in the study only includes data from participants at the end of the 12-month follow-
up. 
- 
Unit of Measure: Not Available 
Outcome Measures: 
- 
Outcome Measure Information: Implant survival and prosthetic complication rate 
   Outcome Measure Type: Primary 
   Outcome Measure Title: Implant survival and prosthetic complication rate 
   Outcome Measure Time Frame: 12 months after delivery of implant-supported restoration 
   Arm/Group Information: There were no separate groups in the study. The study included a 
12-month follow-up of participants with implant-supported single-unit restorations. 
    
Analysis Population Information: 
  Overall Number of Participants Analyzed: 100 participants 
Outcome Measure Data Table 
  Measure Type: Count of Participants 
Measure of Dispersion/Precision: Not Applicable 
Outcome Measure Data: The effect of prosthetic, anatomical and surgical parameters on 
implant survival rate and prosthetic complications 
Unit of Measure: Implant survival  and prosthetic complications rate 
Statistical Test of Hypothesis: 
  P-Value: p<0.05 
  Method: Chi-Squared 
Adverse Event Information: Since this is a retrospective analysis, adverse events were not evaluated. 
Certain Agreements:  
- 
Are all PIs Employees of Sponsor? Yes: The principal investigator is an employee of the 
sponsor 
Results Point of Contact: 
- 
Name or Official Title: Özer İşisağ. Assistant Professor at Afyonkarahisar Health Sciences 
University, Department of Prosthodontics. 
- 
Organization Name: Afyonkarahisar Health Sciences University 
- 
Phone: +905446558727 
- 
E-mail: ozer.isisag@afsu.edu.tr 
Document Upload Information: 
- 
Document Type: Study Protocol with Statistical Analysis Plan (SAP)  
- 
Document Date: 07.04.2023 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
  This retrospective study included 100 volunteer patients aged between 30 and 77 who presented at 
the Department of Prosthetic Dentistry at Afyonkarahisar Health Sciences University Faculty of 
Dentistry for prosthetic treatment and received a single-unit implant-supported crown. The 
evaluation of the included patients was conducted during their 12-month follow-up control 
appointments after prosthetic loading. After obtaining oral and written consent from the patients, 
demographic data, prosthetic complications related to single-unit fixed implant-supported 
prostheses, and peri-implant bone loss assessed via radiographic controls were recorded and 
analyzed. During clinical examinations, the compatibility of the prostheses with adjacent teeth and 
gingiva, the presence of gingival recession, patient complaints about the prosthesis, and any 
prosthetic complications were assessed and recorded. Statistical analyses were performed 
retrospectively after evaluating the collected data. 
Ethical Approval for the Study 
Since participation in this study was voluntary and conducted with volunteers, it was reviewed by the 
Clinical Research Ethics Committee of Afyonkarahisar Health Sciences University. The study was 
unanimously deemed to comply with medical ethical standards (Date: 07.04.2023, Protocol Code: 
2023/4). All volunteers signed an informed consent form approved by the ethics committee before 
participating in the study. 
Volunteer Selection 
This study included 100 volunteer patients who applied to the Department of Prosthetic Dentistry at 
Afyonkarahisar Health Sciences University Faculty of Dentistry for prosthetic treatment and received 
a single-unit implant-supported crown. Patients were selected from archives and evaluated during 
their 12-month follow-up appointments through clinical and radiographic examinations. To 
determine the number of volunteers needed for the study, a sample size calculation was performed 
using GPower software (GPower Ver. 3.0.10, Franz Faul, University of Kiel, Germany). With a 
significance level of α=0.05 (95% confidence interval), an effect size (d) of 0.5, and power (1-β) = 
0.80, at least 80 patients were required. To account for potential dropout and data loss during 
follow-up, an additional 25% (20) patients were added, resulting in 100 patients at the start of the 
study. 

Systemic and dental anamneses of the volunteers were thoroughly evaluated, and inclusion and 
exclusion criteria were established. Patients meeting the inclusion criteria were provided detailed 
information about the study plan before the start. Those who agreed to participate signed the  
Inclusion Criteria 
1. Patients who had received single-unit dental implant treatment and had 12 months elapsed 
since prosthetic loading. 
2. Patients aged 18 and older, regardless of gender. 
3. Patients with no systemic health issues. 
4. Non-smokers. 
5. Patients for whom radiographic bone loss, mobility, and prosthetic complications data were 
recorded and evaluated. 
6. Patients who signed the informed consent form voluntarily after being fully informed about 
the study's purpose, duration, and requirements. 
Exclusion Criteria 
1. Patients diagnosed with osteoporosis and/or undergoing bisphosphonate treatment during 
or after treatment. 
2. Patients with uncontrolled systemic diseases (e.g., diabetes mellitus, heart diseases, liver 
diseases). 
3. Patients with a history of head or neck radiotherapy. 
4. Patients on chronic medication (e.g., steroids, antidepressants). 
5. Smokers. 
6. Patients without radiographs immediately after prosthetic loading. 
7. Patients with psychiatric problems. 
8. Patients with missing data on radiographic bone loss, mobility, prosthetic complications, or 
implant dimensions. 
9. Patients with short implant designs. 
10. Patients who lost implants before the 12-month follow-up. 
Data Collection 
The evaluations conducted during the patients' 12-month follow-up appointments were recorded 
and analyzed. The parameters assessed during these appointments include: 
A. Demographic Data 

1. Age of the patient. 
2. Gender of the patient (Male/Female). 
3. Education level (Primary School, Secondary School, High School, Undergraduate, Graduate). 
B. Clinical Parameters 
1. Tooth brushing habits (None, Once daily, Twice daily, More than twice daily). 
2. Presence of functional pain (Yes/No). 
3. Mobility (Yes/No). 
4. Presence of exudate (Yes/No). 
5. Attached gingiva (≥3 mm) (Yes/No). 
6. Reason for tooth extraction (Endodontic, Periodontal, Other). 
7. Immediate implant placement after extraction (Yes/No). 
8. Implant diameter (Narrow <3.75 mm, Standard ≥3.75 mm and <5 mm, Wide ≥5 mm). 
9. Implant length (Short implants excluded; Standard ≥10 mm). 
10. Implant type by tissue relationship (Bone Level, Tissue Level). 
11. Anatomical location of the implant (Maxillary Anterior/Posterior, Mandibular 
Anterior/Posterior). 
12. Type of abutment (Standard, Screw-Retained, Ti-Base). 
13. Status of the opposing arch (Natural Tooth, Tooth-Supported Fixed Prosthesis, Implant-
Supported Fixed Prosthesis, Implant-Supported Removable Prosthesis, Tooth-Supported 
Removable Partial Prosthesis/Full Denture). 
14. Occlusal table dimensions (Normal/Reduced by 30-40%). 
15. Superstructure material (Metal-Ceramic, Monolithic Zirconia, Monolithic Glass Ceramic). 
16. Presence and history of screw loosening (Yes/No). 
17. Presence and history of cementation loss (Yes/No). 
18. Framework-ceramic separation (Chipping) (Yes/No). 
Data Evaluation 
   Evaluation of Implant Success and Survival 
The success and survival of the implants were evaluated based on the 2007 consensus criteria 
established by the International Congress of Oral Implantologists (ICOI). The data were categorized 

into four groups: Healthy-Successful, Sufficient Survival, Compromised Survival, and Unhealthy-
Failed. 
   Evaluation of Radiographic Bone Loss 
Digital radiographs (periapical and panoramic films) taken at the end of prosthetic treatment and 
during the 12-month follow-up were analyzed using Planmeca Romexis® software (Planmeca, 
Helsinki, Finland). Marginal bone loss was measured using ImageJ software (ImageJ 1.54g, NIH, USA). 
Measurements were calibrated based on the actual implant length. The mesial and distal marginal 
bone loss was calculated separately by subtracting the values obtained immediately after prosthetic 
loading from those at the 12-month follow-up. 
 
 
Statistical Analysis 
The collected data were analyzed using SPSS Statistics V.26 (IBM SPSS Statistics, USA). The normality 
of parameters was assessed using the Kolmogorov-Smirnov and Shapiro-Wilk tests. Descriptive 
statistical methods (mean, standard deviation, median, frequency) were employed. Quantitative data 
and intergroup comparisons were evaluated using the Kruskal-Wallis test, with Dunn’s test for post 
hoc analysis. The Mann-Whitney U test was used for pairwise comparisons, and the Fisher-Freeman-
Halton Exact Chi-Square test was employed for qualitative data comparisons. A significance level of 
p<0.05 was considered statistically significant.