Prosthetic Loading Research Articles

Bone and Soft Tissue Modifications in Immediate Implants Versus Delayed Implants Inserted Following Alveolar Ridge Preservation: A Randomized Controlled Clinical Trial. Part II: Radiographic Outcomes

This study evaluated the radiographic alterations that occur in immediate postextraction implants and in delayed implants inserted in a preserved ridge. In group A, an implant was placed immediately after tooth extraction, grafting the bone-to-implant gap. In group B, alveolar ridge preservation was performed after tooth extraction, and delayed implant placement was performed 4 months later. The final follow-up was 1 year after prosthetic loading in both groups. The marginal bone level (MBL) was measured at implant insertion (T1), at loading (T2), and at the final follow-up, 12 months after prosthetic loading (T3). At tooth extraction (T0) and T3, the horizontal ridge width (HW) was measured on CBCT scans at three different levels. No statistically significant differences in MBL or HW were found between the two study groups. The outcomes suggest that it is possible to maintain MBL and alveolar bone volumes regardless of whether the procedure is performed through immediate postextraction implant placement or through delayed implant placement in a preserved ridge.

Evaluation of marginal bone level after implant placement and before loading, by digital radiography

Background: Marginal bone loss around dental implant is one of the criteria for evaluating implant success. Objectives: To evaluate the marginal bone loss around dental implants using digital radiographs and to determine correlation of mesial and distal bone loss around dental implants with gender and location in either arch in a period of 3-6 months after placement and before prosthetic loading. Methods: An analytical study was undertaken from July 2021 till December 2021, after ethical clearance, in 18 patients on whom 23 implants had been placed at Dhulikhel hospital. After implant placement first radiograph was taken by CE 0297 size 2 PSP plate and Carestream (CS2100) intraoral periapical radiograph machine using paralleling technique (XcpRinn Device) and second at 3-6 months later. The radiographs were viewed using image viewer software (Vistasoft2.0.1) to calculate the bone level. Calculating the difference in bone level at zero month and at 3-6 months gave us the amount of bone loss which was entered in Excel sheet and transferred to SPSS v.22 for analysis and student unpaired-t test was used.Results: The mean bone loss was 0.27 ± 0.2 mm on mesial aspect and 0.13 ± 0.3 mm on distal aspect at the end of the study period. No statistically significant bone loss in relation to gender and location of implant placement was found. Conclusion: Within the limitation of the study, no significant difference was found in the mesial and distal aspect of bone loss around dental implant when compared with different parameters.

Farklı mukozal kalınlıkların implant çevresi krestal kemik kaybına etkisi

A dental implant is a treatment option that is widely used nowadays and provides to giving the aesthetic, function, and phonation back to the patient in dental deficiencies. Nevertheless, the inefficacies of dental implants also draw attention for various reasons. Factors causing early period implant inefficacies are being analyzed and reasons that may be affecting marginal bone loss are being elaborated. In the literature, factors causing marginal bone loss such as premature prosthetic loading, neglected cement residues at the prosthesis stage, micro-gap foundation, infection foundation on the surgery region and traumatic surgery draws attention. One of these reasons is the thickness of the mucosa covering the region that the implant is placed (phenotype). The purpose of our review is to discuss the effect of mucosal thickness in the surgical area on the marginal bone loss in the implant area, within the scope of the literature.

Marginal Bone Loss in Internal Conical Connection Implants Placed at the Crestal and Subcrestal Levels before Prosthetic Loading: A Randomized Clinical Study.

The vertical position concerning the bone in which the implants are placed has been related as one of the factors causing marginal bone loss. The objective of this study was to evaluate the bone loss that occurs before prosthetic loading around tapered internal connection (CIC) implants placed at the crestal (C) and subcrestal (S) levels. Method: A randomized clinical trial (RCT) was carried out, with a sample size of 62 implants placed in 27 patients who underwent radiological controls on the day of placement, at one month, and at 4 months, and stability was measured by resonance frequency analysis (RFA) on three occasions. Results: Bone loss in implants C and S from the time of placement (T0) and the month after (T1) was not significant (p = 0.54) (C = 0.19 mm and S = 0.15 mm). The difference between one month (T1) and four months (T2) (C = 0.17 mm and S = 0.22 mm) was not significant either (p = 0.26). The difference between the day of placement (T0) and the third and last measurement (T2) was almost null (p = 0.94) (C = 0.35 mm and S = 0.36). The overall success rate of the implants was 97.8%. The stability of the implants measured with RFA went from 70.60 (T0) to 73.16 (T1) and 74.52 (T2). Conclusions: No significant differences were found in the bone loss for implants placed at the C and S levels. The millimeters of bone loss detected in both vertical positions did not have a significant impact on the stability of the implants.

Full Digital Workflow for Prosthetic Full-Arch Immediate Loading Rehabilitation Using OT-Bridge System: A Case Report

Nowadays, digital technologies have brought very important advancements in clinical prosthetic dentistry. However, a full digital workflow is still considered to be challenging in the management of full-arch implant cases with immediate prosthetic loading. The aim of this case report is to show a full-digital workflow for the fabrication of an implant-prosthetic fixed provisional prosthesis for immediate loading on seven implants in the upper maxilla. The static guided implant surgery and the OT Bridge prosthetic system were used to rehabilitate the patient. In this way, the combination of a well-known surgical technique with a peculiar prosthetic system that allows for a certain degree of tolerance resulted in it being useful for full-arch immediate loading. Future research and studies are necessary to prove the reliability of this full-digital protocol.

Implant rehabilitation with Strategic Implant® technology in two stage implants – bone addition, sinus-lift failure (cases presentation)

In this article, the authors want to present the possibilities of solving some difficult cases, treated in a conventional surgical and implant manner and which were a failure, as well as the possibilities of avoiding these failures using Strategic Implant® technology. In the first case presented, the patient goes through bone augmentation procedures, without reaching the time of implant insertion and prosthesis, with the loss of bone addition on one side of the mandible, the case being later completed with corticobasal implants in immediate prosthetic loading. The second case in which the patient successively loses the inserted two stage implants, without reaching their functional load, resorts to the treatment with corticobasal implants in immediate loading and the fixed prosthetic restoration of the mandible in 3 days postimplantation. The last case in which the patient comes for the removal of a maxillary prosthetic work fixed on 4 two stage implants with bone addition and unilateral sinuslift, with mobility, and in which the treatment with corticobasal implants and fixed prosthetic work in 3 days was the optimal way of treatment. These cases as well as the feedback of the treatment after a number of years show us that the treatment with corticobasal implants can be made much easier using only the native bone of the patient using implants that adapt to the morphology of the existing bone and a immediate loading protocol to allow the optimal functioning of prosthetic works; knowledge of surgical and prosthetic protocols of Strategic Implant® technology lead to predictable prosthetic results with minimally invasive surgery, without sinus lift and bone addition, in a short time of 3 days from the surgical step until the final oral rehabilitation.

Peri-implant bone microstructural analysis and comparison of resonance frequency analysis before prosthetic placement: a retrospective study.

ObjectivesFractal analysis is a mathematical method used for the calculation of bone trabeculation and lacunarity. This study aims to evaluate the relationship between resonance frequency analysis (RFA) and fractal dimension (FD) of peri-implant bone to determine the preload stability of implants.Materials and methodsIn this study, the results of the fractal analysis calculated from the resonance frequency analysis results taken in the 3rd month of the patients who underwent 2-stage implant by the same doctor and the radiographs taken in the same session were evaluated. A hundred implants in 20 patients were applied in this study. The implant stability quotient (ISQ) values of the implants and fractal dimension values of the peri-implant bone were calculated.ResultsThe findings showed that the ISQ1 (p = 0.008), ISQ2 (p = 0.038), ROI2 (p = 0.013), and ROI3 (p < 0.001) values were statistically significantly higher in men than women. The ISQ1 (p = 0.003), ISQ2 (p = 0.013), ROI1 (p = 0.011), and ROI3 (p < 0.001) of the mandible were statistically higher than the maxilla. The fractal dimension cut-off value to assess prosthetic loading was found 1.198.ConclusionFractal analysis is a non-invasive method that can be used in conjunction with clinical examination in the prosthetic loading decision of implants. It is a valuable parameter that can be used without the need for an extra device when it is necessary to reduce the clinical study time.Clinical relevanceCalculating the fractal dimension of the peri-implant bone is a practical, economical, and applicable method for clinicians. FD calculated from panoramic radiographs used for diagnosis in routine treatments in clinics where access to the necessary devices for ISQ measurement is not available will contribute to clinical practice.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00784-022-04464-3.

Comparative Study by Systematic Review and Meta-Analysis of the Peri-Implant Effect of Two Types of Platforms: Platform-Switching versus Conventional Platforms.

Objective: The aim of the systematic review and meta-analysis carried out was to evaluate the effects of changing the prosthetic platform on peri-implant tissue after 1 year of prosthetic loading. Material and methods: In November 2020, an electronic search was carried out in PubMed, EMBASE, Web of Science, and Scopus databases with the aim of obtaining all the randomized clinical trials that had been published in the preceding 10 years comparing the effects on the peri-implant tissue of implants with a prosthetic platform change and implants with a conventional platform for at least 1 year after prosthetic loading. Randomized model meta-analyses of the selected studies were performed to compare the results of the two implant groups in terms of vertical maintenance of bone level and increased probing depth. Results: Nine studies were included, summing up a total of 475 implants with prosthetic platform exchange and 462 implants with a conventional platform. Implants with prosthetic platform exchange had less peri-implant bone loss than implants with a conventional platform (mean difference of 0.255 mm, statistically significant) but suffered a greater increase in probing depth (mean difference of 0.082 mm, not statistically significant). However, the probing depth from One Study Remove revealed a statistically significant increase of 0.190 mm in the prosthetic platform exchange group compared to the conventional platform group. Conclusion: Implants with platform switching suffer less peri-implant bone loss after 1 year of loading than implants with a conventional platform. Further long-term studies are required to observe how these differences vary over time.

Analysis of Peri-Implant Bone Loss with a Convergent Transmucosal Morphology: Retrospective Clinical Study

Objective: The aim of this study was to analyze the peri-implant bone loss of infracrestal, supracrestal, and crestal implants from the day of placement and up to 1 year of prosthetic loading. Material and methods: A retrospective clinical study was carried out. The sample consisted of 30 implants placed on 30 patients. It was divided into three groups: infracrestal (n = 10), crestal (n = 10), and supracrestal (n = 10) implants. Results: Following the statistical analysis, it was observed that, 4 months after implant placement, the mean values of total peri-implant bone loss were 0.04 mm in infracrestal implants, 0.26 mm in crestal implants, and 0.19 mm in supracrestal implants. At the end of one year of prosthetic loading, the peri-implant bone loss was 0.12 mm in infracrestal implants, 1.04 mm in crestal implants, and 0.27 mm in supracrestal implants. It was determined that peri-implant bone loss in crestal implants was significantly higher than in supracrestal implants, and these in turn were significantly higher than in infracrestal implants. Conclusions: The implants that obtained a better biological behavior on peri-implant bone tissue were the infracrestal implants with a converging transmucosal abutment.

Retrospective Study of Biohorizons® Implants Placed by Postgraduate Students at the University of Barcelona

The study aimed to evaluate the survival and failure rate, in the short- and medium-term, in addition to its relationship with risk factors, in implants placed by postgraduate students of the Master of Medicine, Surgery, and Oral Implantology course from the University of Barcelona. The study was designed including 192 patients with 422 implants placed between 2015 and 2018. Variables of implant failure were evaluated and related. Failure was split into early failure and late failure. Qualitative data were compared using the chi-squared test, taking p ≤ 0.05 as a significant value. The comparison of quantitative variables was carried out using the Student’s t-test for independent samples. The survival rate in a period of 6 months to 3 years was 97.87%. The mean age of the patients was (54.5 ± 13), and the largest number of implants were placed in the 51–60 age range. The failure rate was 2.13% (N = 9), 6 failed early and 3 failed after definitive prosthetic loading, with a p value &lt; 0.0001. When comparing the failures according to their location in the anterior/posterior sector of the arch, the anterior sector showed statistically significant results (p = 0.027). Failed implants had a statistically significant relationship when they were placed in the anterior sector and were performed in the early stage.

Evaluation of the Effects of Attachment Type and Implant Number on Life Quality of Implant-Supported Mandibular Overdenture Prosthesis Patients

Objective: The current study aimed to evaluate the life quality of implant-assisted mandibular overdenture patients who have had additional implant applications and were rehabilitated with ball or bar attachment. Material and Methods: 53 patients who came to Van Yüzüncü Yil University, Faculty of Dentistry, Prosthodontics Clinic for implant-supported mandibular overdenture treatment between 2019 and 2021 were included in this prospective clinical study (32 females, 30 males; mean age: 64.03; age range: 33-90). The patients were called back for the study precisely one year after prosthetic loading of their implants. Implant-supported mandibular overdenture prosthesis patients diverged into six groups: splinted two implants (bar attachment), single two implants (ball attachment), splinted three implants (bar attachment), single three implants (ball attachment), splinted four implants (bar attachment) and single four implants (ball attachment). And they asked for completing the Turkish version of the OHIP-14 questionnaire. Results: Ball attachment was used in 45.28% of the participants, a mandibular overdenture design supported by a bar attachment was preferred in 54.72%. Kruskal-Wallis test results indicated that the number of implants had a statistically significant effect only on functional limitation and psychological disability among the seven OHIP-14 categories evaluated (p=0.018, p=0.009). Accordingly, the average functional limitation score in individuals with four implants was 4.44 ± 1.89. Conclusion: We found that there are a positive correlation between the number of implants and the patient's life quality; however, it can be concluded that attachment type does not significantly affect the scores of the life quality

Primary and Secondary Stability of Extrashort (4-mm) Implants in the Edentulous Mandible: Preliminary Results of a Prospective Clinical Trial

To compare the primary and secondary stability of conventional (≥ 8-mm) and extrashort (4-mm) implants in edentulous patients using different methods of assessment. Patients underwent implant surgery and were randomly allocated into two groups: test, with two conventional implants in the anterior region and two extrashort (4-mm) implants in the posterior region; and control, with two conventional (≥ 8-mm) implants in the anterior region only. Primary stability (S1-implant placement) was assessed by insertion torque, implant stability quotient (ISQ, Osstell), and damping capacity (PTV, Periotest), while secondary stability (S221-21 days after S1; and S2clip-at prosthetic loading, ± 3 months after S1) was evaluated by ISQ and PTV. The statistical significance level was set at P < .05. Fifty conventional implants and 24 extrashort implants were placed in 25 patients. The overall survival rate was 97.3%. There was no statistically significant difference between the insertion torque of conventional and extrashort implants (P > .05). PTV values were significantly lower for conventional implants only at S2clip (P = .041). ISQ values were significantly greater for conventional implants at S1 (P = .004), whereas at S221 and S2clip, no differences were found (P = .413 and P = .490, respectively). Damping capacity showed no significant differences between S1-S2M21 and S1-S2clip. ISQ values showed a significant increase of stability between S1-S2clip, for conventional (P = .022) and extrashort (P = .005) implants, which was different from that observed between S1-S221. There was a moderate negative correlation between the PTV and ISQ variables (r = 0.5) of extrashort implants, and between the PTV and insertion torque (r = -0.3) of conventional implants. For extrashort implants, there was a null correlation between ISQ and torque (r = 0.0). There was a moderately positive correlation between ISQ and torque (r = 0.3) in the conventional implant group. The results suggest that extrashort and conventional implants present similar primary and secondary stability values and may similarly influence restorative protocols.

Osteotome-Induced Blood Clot and Subsequent Bone Formation with the Use of Collagen Sponge for Integration of Single Dental Implants into the Atrophied Posterior Maxilla: A Retrospective Follow-Up of 36 Implants after 5 to 13 years.

Background Atrophy of the posterior maxilla as a consequence of tooth loss and sinus pneumatization is a frequent condition encountered in the clinical practice. Prosthetic rehabilitation with implants in these patients often requires some kind of bone regeneration procedure to increase the bone volume. Aim The aim of the present retrospective study is to analyze the survival and success rates of a series of implants placed in the atrophic posterior maxilla with a transcrestal osteotome procedure, without placing a bone grafting material. Materials and Methods From 2006 to 2014, 36 dental implants (Neoss Ltd., Harrogate, UK) were inserted in 36 patients with at least 4 mm of bone below the maxillary sinus using transcrestal osteotome sinus floor elevation and placement of collagen sponge below the sinus membrane. ISQ measurements were made after implant placement and at abutment surgery after 4 to 6 months. The vertical bone height (VBH) was evaluated in intraoral radiographs taken prior to surgery and in radiographs from annual check-up appointments 5 to 13 years after implant placement. In addition, marginal bone loss (MBL) was evaluated. Results One implant was lost after four years of prosthetic loading. The remaining 35 implants showed no complications and were loaded with single crowns after 4–6 months of healing. All 35 implants showed clinical success after 8.5 ± 2.8 years of prosthetic loading (from 5 to 13 years). The vertical bone height was 5.9 ± 1.4 mm at surgery, 9.7 ± 1.1 mm at second surgery after 4–6 months, and 8.3 ± 1.8 at the follow-up at 8.5 ± 2.8 years (from 5 to 13 years). The implant stability registered was 73.2 ± 6.2 ISQ at the surgery and 75.8 ± 3.9 at the second surgery after 4–6 months. Conclusions The present long-term follow-up study showed that the crestal approach for sinus floor bone augmentation without additional bone grafting results in predicable bone formation and high implant survival. The osteotome technique is a valid alternative to the more invasive lateral window technique in single cases with a minimum of 4 mm of VBH below the maxillary sinus.

Minimally Invasive Management of the Edentulous Space in the Anterior Sector without Prosthetic Loading

Introduction: Osseointegration is nowadays considered highly predictable, so minimally invasive surgical approaches are sought in order to allow proper function and a good esthetic result. It is of great importance to determine whether the shape and surface of the implant is an important factor in conjunction with the surgical technique. Objective: To evaluate the use of tomographic surgical guidance for the placement of a V3 implant in edentulous space in the maxillary esthetic zone. Method: A 53-year-old male patient with a vestibularly collapsed edentulous area corresponding to the left upper lateral. The treatment used was the IN2GUIDE system and MIS V3 implant, with evaluation up to 90 days. Results: Bone loss at the level of the implant platform without receiving any type of load. Discussion: Bone and peri-implant soft tissue loss will be similar with any procedure.

Influence of Crown Height of Dental Implant on Marginal Bone Loss: A Retrospective Study

Bone loss around implant necks has traditionally been regarded as an indicator of implant success over the long term. Both surgical and prosthetic variables have been linked to premature marginal bone loss. Early marginal bone loss (MBL) &gt;0.44 mm in the first six months following prosthetic loading is a risk indication for peri-implant bone loss development, according to new research on crystal-level implants. To determine the effect of crown height of dental implant on marginal bone loss. Th

Effects of wearing removable dentures and aging on palatal mucosa blood flow by laser doppler.

The purpose of this work is to analyze the effects of removable dental prostheses and aging on blood microcirculation in the palatal mucosa. Blood flow was measured in two groups using the Laser Doppler Flowmeter at three specific anatomical sites: Retro incisive papilla, medial raphe, and Schroeder area. Group 1 included young, healthy dentulous individuals (mean age: 23 ± 3 years), and Group 2 contained elderly edentulous individuals (mean age: 62 ± 11.69 years). For Group 1, measurements were taken in a single session; for Group 2, the measurements were taken in two sessions: The first just before the prosthetic load (E1) and again 1 week after new dentures were provider (E2). Statistical analyses were performed using SAS software, Version 9.4 of the SAS System for Windows, Copyright © 2017 SAS Institute Inc. (Cary, NC, USA). A P < 0.05 was classified as statistically significant. Measurements of blood flow of the palatal mucosa showed that the healthy young dentulous participants had significantly lower perfusion unit values than the elderly edentulous participants at all three anatomical sites (P < 0.05). For Group 2, the comparisons between the measurements taken before (E1) and after (E2) new dentures were provided showed no significant differences. Our results indicate that the process of aging significantly modifies the blood flow of the palatal mucosa while wearing removable dental prostheses does not modify the blood flow of the palatal mucosa in a 1week period. These results are not influenced by systemic pathology (e.g., diabetes, cardiovascular diseases) or smoking.

Comparative evaluation of implant stability with and without autologous platelet-rich fibrin prior to prosthetic loading - A split-mouth randomized clinical trial.

Context:Status of bone–implant interface or osseointegration can be assessed by using resonance frequency analysis (RFA), which measures implant stability. A modified implant surface can significantly enhance osseointegration and reduce healing period. Platelet-rich fibrin (PRF) consists of fibrin mesh with entrapped platelets and leukocytes that release a huge number of growth factors which contribute to wound healing and tissue regeneration.Aims:The present study aims to evaluate the effect of PRF on osseointegration in terms of implant stability.Settings and Design:This was a split-mouth randomized clinical trial.Materials and Methods:Sixty surgical sites were divided randomly into two groups. In Group 1 (thirty sites), PRF was placed in osteotomy sites before implant placement whereas no PRF was placed in Group 2 (thirty sites). Stability was measured using RFA in terms of implant stability quotient (ISQ) at baseline, 1 week, 1 month, and 3 months.Statistical Analysis:Intergroup comparison was done using Mann–Whitney U-test. Intragroup comparison was done using Friedman's test followed by pairwise comparison using Wilcoxon signed-rank test.Results:On intergroup comparison, Group 1 showed higher values for ISQ which were statistically significant (P < 0.05) at 1 week and 1 month. No significant difference (P > 0.05) was found at baseline and 3 months. Intragroup comparison and further pairwise comparison revealed a highly significant difference for values between all pairs of time intervals (P < 0.01) with higher values at 3 months.Conclusions:PRF has a significant effect on osseointegration of dental implants during the early healing period prior to loading.

A 5-Year Satisfaction Outcome Study of Patients Receiving Six-Implant-Supported Fixed Prosthesis.

The aim of the study was to analyze the satisfaction of patients treated with a protocol of six-implant-supported fixed prosthesis (6IFP) throughout 5 years of service. This retrospective study collected the data of all patients who had full-arch rehabilitations using 6IFP and followed them for 5 years. After applying the research inclusion/exclusion strategy, 37 cases were finally included in the study. All the patients had no previous complete dentures because they were partially edentulous, not interested in pursuing complete denture rehabilitation, had immediate dental extractions, implantation used the 2-stage protocol, and there was minor peri-implant socket grafting. Cases with severe bone loss that required extensive grafting were excluded. A total number of 222 implants were placed in the maxillary or mandibular arches in a total of 37 patients. The data presented the satisfaction outcomes concerning mastication, phonetics, and comfort during the first 5 years of the recall plan. The former was achieved based on the clinical record reviews, follow-up visits, and recall phone calls at the preoperative stage as well as annually thereafter. The mean satisfaction rate was 94.5%, with a mean record of 8.21 ± 1.7 out of 10, there was no gender predilection significance, and no age range variation significance was validated. Regarding the smoking status, the t-test score exhibited no significant effect on phonetics and mastication (p = 0.12, p = 0.16, respectively), whereas comfort was found to be significantly affected (p = 0.03). The comfort level was found to be slightly less at the immediate postoperative period among smokers when compared to non-smokers. In conclusion, partially edentulous patients who received the rehabilitation plan of arch dental extractions, six immediate implantations, and delayed prosthetic loading were found to be highly satisfied.

Effect of Opposite Tooth Condition on Marginal Bone Loss around Submerged Dental Implants: A Retrospective Study with a 3-Year Follow-Up

Background: The objective of this study was to evaluate the effects of opposite tooth conditions on change in marginal bone level (MBL) around submerged dental implants. Materials and methods: The study included healthy patients with one or two implants. Structures opposite implants were either natural teeth (NT) or fixed restorations (FRs). MBLs were measured on digital periapical radiographs at the mesial and distal aspects of each implant. Results: Sixty implants were inserted by the 3-year follow-up. Mean MBLs for NT were 0.21 ± 0.33 mm before prosthetic loading and 0.30 ± 0.41 mm 3 years later (p = 0.001). Mean MBLs with FRs were 0.36 ± 0.45 mm before loading and 0.53 ± 0.50 mm 3 years later (p < 0.001). Changes in mean MBL from the 6-month follow-up to the 1- and 3-year follow-ups were statistically significant (p < 0.01) for implants opposite NT. However, changes in mean MBL from the 6-month follow-up to the 1-year (p = 0.161) and 3-year follow-ups (p = 1.000) were not significant for implants opposite FRs. Between baseline and the 3-year follow-up, MBL change was relatively small and did not differ regarding NT and FRs. Conclusion: Bone loss was greater if submerged dental implants were opposed by FRs. MBLs around submerged implants continued to change after 3 years if NT opposed implants.

Logistic Regression Analysis of the Factors Involved in the Failure of Osseointegration and Survival of Dental Implants with an Internal Connection and Machined Collar: A 6-Year Retrospective Cohort Study.

Background Although the long-term success rate of dental implants is currently close to 95%, it is necessary to provide more evidence on the factors related to the failure of osseointegration and survival. Purpose To establish the risk factors associated with the failure of osseointegration and survival of dental implants with an internal connection and machined collar and to establish a predictive statistical model. Materials and Methods An analytical, retrospective, and observational clinical study of a sample of 297 implants with a follow-up of up to 76 months. Independent variables related to the implant, patient, and surgical and rehabilitative procedures were identified. The dependent variables were failure of osseointegration and failure of implant survival after prosthetic loading. A survival analysis was carried out by applying the Kaplan-Meier model (significance for p < 0.05). The log-rank test and the Cox regression analysis were applied to the factors that presented differences. Finally, the regression logit function was used to determine whether it is possible to predict the risk of implant failure according to the analyzed variables with the data obtained in this study. Results The percentages of osseointegration and survival were 97.6 and 97.2%, respectively. For osseointegration, there were significant differences according to gender (p = 0.048), and the risk of nonosseointegration was 85% lower in women. Regarding survival, the Cox analysis converged on only two factors, which were smoking and treatment with anticoagulant drugs. The risk of loss was multiplied by 18.3 for patients smoking more than 10 cigarettes per day and by 28.2 for patients treated with anticoagulants. Conclusions The indicated risk factors should be considered, but the analysis of the results is not sufficient to create a predictive model.