I Do Biotech Dental Implants: Prospective Multicentric Study after 5 Years of Functional Loading

Introduction: I Do Biotech’s implants were developed starting in 2014. Since then, they obtained GMP and KFDA licenses for distribution in 2015. The main objective of this paper is to determine the survival rate of I Do Biotech implants five years after the first surgery. Material and Methods: 1000 implants were used on 480 prostheses across 10 clinics on 320 healthy, non-smoker and non-diabetic patients, chosen at random, of which 160 are male and 160 female, all in the age range of 30 to 50 years old. The failure rate was studied related to the patient’s gender, the length and diameter of the implant, anatomical location, the percentage of peri-implantitis, prosthodontic failures and the patient’s quality of life. Discussion: The results obtained are similar to those of Van Steenberghe D. Dieter-Busenlechner, E. Serrano Catauria and far superior to those of Sáenz Guzmán. Failure rates vary greatly from study to study due to the heterogeneity of the samples in the other research papers. Conclusion: The overall implant failure rate at 5 years is 1.7%. The factors affecting significantly the survival rate are: the implant diameter, its length and the anatomic area. Failure ratios increase significantly when the diameter or the length of the implant decreases, and when they are placed in the posterior maxilla (up to 4.3%). The rate of peri-implantitis is 5.1%. The prosthodontic failure rate is 2.91%. The improvement in quality of life and satisfaction increases with the years.


Introduction
Modern oral implantology began with Professor P.I. Brånemark (1969) [1], who in 1952 was working on the microscopic mechanisms of bone healing and discovered that the titanium cylinder had fused with the bone. He called this phenomenon "osseointegration".
In 1977, Professor Brånemark published his first paper on implantology and in 1982 presented his studies at the Toronto Conference Zarb G.A. (1990) [6]. Since then, the design of the implant, its prosthetic connection and the treatment of its surface have evolved, all with a view to increasing the success rate and reducing treatment times.
The I Do Biotech implant is a conical trunk implant, with an 11-degree prosthetic Morse taper and a bioactive surface according to the procedures specific to the SLA technique ( Figure 1).
The study was designed by distributing 1000 implants among ten implant clinics with more than seven years of experience and without any commercial relationship with the I Do Company. Each prosthesis was accompanied by a form to be filled out by the clinic and the patient together (Table 1).   This paper refers to the results of the multicentric study after 5 years of functional loading. The date of surgery was not taken into consideration, but each of the 1000 implants had completed 5 years of loading.
The implants had to be inserted in bone without any type of GTR. No patient could be a smoker or diabetic and all of them were loaded three months after the first surgery.
The main objective of this paper is to assess the survival of I Do Biotech im-

Description of the I Do Biotech Implant and Its Surgical Insertion Technique
The It is sold with 7 types of diameters (3.8, 4.0, 4.5, 5.0, 5.5, 6.0 and 7.0) and 6 types of lengths (7, 8.5, 10, 11.5, 13 and 15). It is presented in a double package sterilized with Gamma rays.
Regarding the surgical technique, it is a regulated, ergonomic, and simple procedure. All necessary surgical equipment is orderly presented in a surgical kit. It consists of 3 burs. The first is the Lindemann bur with which we approach the cortical; with the second tapered twist drill, we reach the desired working length; and with the third and final one we use a tapered bur, which reproduces the morphology of the implant with 0.45 mm more length and 0.8 mm less diameter ( Figure 2).
The implant is inserted at 35 Ncm and positioned 0.5 mm under the crest.
In this study, all implants were 7 and 10 mm long, and 3.8, 4 and 5 mm in diameter, loaded at 3 months, with 5 years of functional loading.

Selection of Implantologists
Only implantologists with a minimum of seven years of clinical experience and without any commercial relationship with the company I Do were invited. Ten surgeons were selected ( Table 2) and one hundred implants were provided to each one, indicating to them their assigned anatomical areas and the form that they had to fill in each year for the five years of the study.

Selection of Patients
This study was carried out on 320 patients, 50% female and 50% male, chosen at random within the population of the doctor's patients taking part in the study that matched the inclusion criteria. They had agreed to attend the check-up appointment once a year; and had signed the informed consent form. The inclusion criteria were: generally healthy, non-smoker, non-diabetic patients between 30 and 50 years old. They did not require any GTR technique at the time of the first surgery; and had a bone height greater than 10 mm and a minimum width of 8 mm. They didn't have any history of sever periodontal disease either. These criteria were chosen to remove factors that impacted failure rates.

Selection of the Implants
There were five hundred implants of 10 mm in length and another five hundred of 7 mm in length. The diameters were four hundred units of 3.8 mm diameter, four hundred units of 4 mm diameter and two hundred units of 5 mm diameter.

Anatomical Location of the Implant
The implants were divided into four groups.

3) Anterior inferior (mandibular symphysis). 4) Posterior inferior.
Fifty units of each diameter and length were used in each location, except for the 5 mm diameter implants, which were only used in the posterior areas (Table  3).

Related to the Implant: Diameter and Length
In each of these subgroups, the failure and complication rates were measured: bleeding, suppuration, gingival hyperplasia, bone loss (measured in intraoral Open Journal of Stomatology X-rays with Kodak RVG 5100, measuring mesial, distal and total loss (mesial + distal/2).

Related to the Prosthesis
Single-tooth prosthesis, fixed prosthesis with more than one implant, hybrid and their antagonist. Each subgroup measured screw fracture, porcelain fracture and prosthetic fracture.
As it was a prospective study, each of the dentists was allocated a number of implants, indicating where it had to be placed and what type of prosthesis should be performed, which resulted in a homogeneous sample (Table 4). In total, 480 prostheses were placed.

Related to the Type of Edentation
Superior, inferior, anterior and posterior.

Related to the Patient
On each yearly check-up, three factors were taken into account in order to assess the patients: -Proper hygiene maintenance and impact on the oral health profile (bad taste in the mouth, smell, inability to lead a normal life, difficulty with speech, aesthetic impact). -Evolution of the patients' quality of life over these five years, according to the OHIP-14 protocol, with all patients filling out a form. -Satisfaction of the patient with the treatment, on a scale of 0 (Not satisfied) to 5 (completely satisfied). They were matched against other patient's results that the same doctors treated using removable prosthesis. Table 3. Implants distribution for length, diameter, and anatomic place.

Statistical Processing
This is a cohort study design.
The data obtained by the doctors and sorted in Excel was entered into the SPSS software package (v 12.0).

Descriptive Statistics
The percentages of each of the variables were studied.

Inferential Statistics
The null hypothesis (there is a relationship of independence) must be rejected (i.e. the relationship between variables is dependency) when the minimum probability of rejection (p-value) does not exceed 0.05.
Once the variables were determined to be homogeneous, Pearson's chi-squared test was used to study the associations between continuous quantitative variables, thereby establishing hypothesis contrasts.
In the correlation between various variables multinomial logistic regression RR (risk ratio) was used (implant length and diameter for implant failure, and bone loss great than 2 mm for peri-implantitis) and the risk factors were age, gender, oral hygiene, and anatomical location, calculating 95% confidence intervals (Pv.0.05). This allows us to express the likelihood of implant failure.

Implant Failure
When comparing the homogeneity of the implant diameters and lengths with respect to their topographic location, it was verified that all samples were homogeneous with respect to age (Pv 0.0388), gender (Pv 0.0178) and oral hygiene (Pv 0.0405).
In the descriptive statistical analysis, we studied the failure rate of the sample and the failure rate of each variable. For the exploratory analysis of association of variables, Pearson's chi-squared test and multinomial logistic regression were used. The significance level was set at 0.05.
The failure rate over all implants is shown in Table 5.
In Table 6, we can see the failure rate according to anatomical location.
The failure rate which links implant length with diameter is shown in Table 7.
For Pv = 0.05 value, implants with 7 mm length for 3.8 diameter and 10 mm length for 3.8 diameter have a difference statistically significant. The chi-squared test showed that if the H˚ (null hypothesis) is "No length influence in failure", the chi squared calculated was 6 and the chi square table 3.84. That means that the null hypothesis is rejected and the rate of failure is limited to the length and diameter of the implant with a Pv = 0.010, with the difference being statistically very significant. As for gender, the chi-squared was Pv = 0.720 and no relationship was found between failure and gender.  Of the 1000 implants, 17 failed, accounting for 1.7%. Of these failed implants, 88.7% were due to osseointegration failure, with peri-implantitis being the cause of failure in 11.3% of cases (7% percussion pain and 93% peri-implant fibrosis with implant mobility).
The association between narrow diameter and short implant in posterior areas presented a RR (risk ratio) of 5 with a confidence interval between 1, 7 and 6, 5, for Pv = 0.001.
The multinomial regression study indicated that age, gender, and alcohol do not have an influence, while oral hygiene do have an influence on the presence of peri-implantitis (Table 8).
Bone lysis was measured annually, obtaining the following values ( Figure 4).
The percentage of periimplantitis increases over time from 0% to 5.1% at five years of function.

Related to the Prosthesis
Regarding the prosthesis, the implant failures were related to the type of prosthesis and its antagonist.

Type of Prosthesis
The total survival figure of the prosthesis was 468 (2.91% failure). Out of this failure rate, 57.1% corresponds to single-tooth prostheses, 35.7% to fixed prosthesis of more than one implant, and 7.1% to hybrids (Table 9).

Antagonist
The failed implant antagonist was a natural tooth in 70.5%, fixed prosthesis on teeth in 17.6%, fixed prosthesis on implants in 5.8%, and removable prosthesis in 5.8%.

Screw Fractures
There were no reported screw fractures. Open Journal of Stomatology

Evolution of the Quality of Life and Satisfaction
On comparing the quality of life among patients wearing I Do Biotech implants with the same patients wearing a skeletal or fully removable prosthesis, a significant improvement was observed. On a scale of 0 to 5, where 0 is absence of disability and 5 is maximum disability, the results shown in Table 10 were obtained.
The degree of satisfaction of patients with I Do Biotech implants compared to others with removable prostheses was quantified by measuring the level of satisfaction in each of the 320 patients (Table 11).

Discussion
This paper is a prospective clinical study based on a group of selected patients, Derks J. (2016) [7], carried out by a group of expert surgeons like Berglundh T. (2013) [8] and, although the methodology was questioned due to involving patients under optimal conditions, it provides results attributable to the quality of the implant, eliminating failure factors due to the patient, the surgeon or the surgical technique.  The study by Curto A.A. (2012) [21] shows a 10.7% failure rate for implants smaller than 7 mm and 5.9% for implants greater than or equal to 10 mm. In our study the failure rate for 7 mm and 3.8 mm diameter was 5%.
(1990) [23] proposes a 5% failure rate after 5 years and 8% after 15 years.  10.3% in the anterior maxilla, 4.5% in the posterior jaw and 2.3% in the anterior jaw. As for the type of prosthesis, 17.5% in single-tooth implants, 7.9% in hybrid denture and 5.8% in fixed prosthesis of more than one implant. In our study we had 9 failures over 480 prothesis 55% in single-tooth implants, 33% in fixed prosthesis with two implants and 11% in hybrid denture.
Our study coincides with that of Fartash B. (1997) [37], finding no differences regarding gender.
The highest failure rate is found in the conjunction of poor bone quality, short implant and small diameter.
The overall peri-implantitis rate was 5.1%. At the 1994 European Workshop, Isidor F., Albrektsson P. (1994) [4], the reversible inflammatory reaction in the gum surrounding a functioning implant was defined as "mucositis", indicating that it occurs in 80% of the implants and increases over the years, Roos-Jansåker The best peri-implantitis results obtained in our study, 5.1% at five years, may be due to the fact that since this was a prospective study, we did not include smokers, patients with a history of aggressive peri-implantitis or diabetics. In addition, we only choose cases where no GTR techniques were performed and loading was deferred at three months, while we also subjected patients to strict Open Journal of Stomatology hygiene controls and used an intermediate rough surface implant ( Figure 5).
Increasing the Ra value favours the proliferation of osteoblasts, but also of bacteria and, consequently, the rate of peri-implantitis. Bone-implant contact increases with surface roughness from value 1. To assess the quality of life, the OHIP-14 questionnaire, Lindeboom A.J.   Our study found no differences between men and women, while Lee did find some in terms of pronunciation, taste and discomfort.

Conclusions
The failure rate of the I Do Biotech implant after 5 years was 1.7%. It increases up to 4.3% when the length of the implant or its diameter decreases, and when it is placed in posterior areas.
The failure rate of the prosthesis after 5 years was 2.91%.
The rate of peri-implantitis after 5 years was 5.1%.
No significant differences were found between both genders, so it can be said that gender does not influence failure rates.
With a statistically significant difference, the highest failure rates were seen with short implants, smaller diameter, and located in the posterior areas of the maxilla.
The quality of hygiene decreases over the years and the rate of peri-implantitis increases.
The roughness of the I Do Biotech implant is ideal for increasing the rate of osseointegration without increasing the rate of peri-implantitis.
The conical form of the I Do Biotech implant connection guarantees the stability of the prosthesis.
The perception of improved quality of life and patient satisfaction grows over the years.
As this was a prospective study with highly selected patients and dentists, it is not possible to transfer this data to the general population, as it is limited to the I Do Biotech implant used in optimal conditions.

Conflicts of Interest
The authors declare no conflicts of interest regarding the publication of this paper.