Long-Term Clinical Outcomes of Treatment with Dental Implants with Acid Etched Surface

Silver coating on dental implant-abutment connection screws as potential strategy to prevent loosening and minimizing bacteria adhesion

Introduction: One of the main problems for the long-term behavior of dental implants are loosening of the implant-abutment connection screws and bacterial infiltration. The aim of this work is to increase the screw fixation by silver coating, providing superior mechanical retaining and antibacterial effect. Methods: Eighty dental implants with their abutments and screws have been studied. Twenty screws were not coated and were used as a control while the rest of screws were silver coated by sputtering, with three different thickness: 10, 20 and 40 μm and 20 screws per each thickness. Coating morphology and thickness were determined by scanning electron microscopy using image analysis systems. The screws were tightened for each of the thicknesses and the control with two torques 15 Ncm and 20 Ncm and tested under mechanical fatigue simulating oral stresses up to a maximum of 500,000 cycles. The remaining torques at different cycles were determined with a high-sensitivity torquemeter. Cell viability assays were performed with SaOs-2 osteoblasts and microbiological studies were performed against Streptococcus gordonii and Enterococcus faecalis bacteria strains, determining their metabolic activity and viability using live/dead staining. Results: It was observed a decrease in torque as cycles increase. For a preload of 15 Ncm at 100,000 cycles, the loosening was complete and, for 20 Ncm at 500,000 cycles, 85% of torque was lost. The silver coatings retained the torque, especially the one with a thickness of 40 μm, retaining 90% of the initial torque at 500,000 cycles. It was observed that osteoblastic viability values did not reach 70%, which could indicate a slight cytotoxic effect in contact with cells or tissues; however, the screw should not be in direct contact with tissue or living cells. Silver coating induced a significant reduction of the bacteria metabolic activity for Streptococcus gordonii and Enterococcus faecalis, around 90% and 85% respectively. Discussion: Therefore, this coating may be of interest to prevent loosening of implant systems with a worthy antibacterial response.

Relevant Aspects of Titanium Topography for Osteoblastic Adhesion and Inhibition of Bacterial Colonization

The influence of the surface topography of dental implants has been studied to optimize titanium surfaces in order to improve osseointegration. Different techniques can be used to obtain rough titanium, however, their effect on wettability, surface energy, as well as bacterial and cell adhesion and differentiation has not been studied deeply. Two-hundred disks made of grade 4 titanium were subjected to different treatments: machined titanium (MACH), acid-attacked titanium (AE), titanium sprayed with abrasive alumina particles under pressure (GBLAST), and titanium that has been treated with GBLAST and then subjected to AE (GBLAST + AE). The roughness of the different treatments was determined by confocal microscopy, and the wettability was determined by the sessile drop technique; then, the surface energy of each treatment was calculated. Osteoblast-like cells (SaOs-2) were cultured, and alkaline phosphatase was determined using a colorimetric test. Likewise, bacterial strains S. gordonii, S. oralis, A. viscosus, and E. faecalis were cultured, and proliferation on the different surfaces was determined. It could be observed that the roughness of the GBLAST and GBLAS + AE was higher, at 1.99 and 2.13 μm of Ra, with respect to the AE and MACH samples, which were 0.35 and 0.20 μm, respectively. The abrasive treated surfaces showed lower hydrophilicity but lower surface energy. Significant differences could be seen at 21 days between SaOS-2 osteoblastic cell adhesion for the blasted ones and higher osteocalcin levels. However, no significant differences in terms of bacterial proliferation were observed between the four surfaces studied, demonstrating the insensitivity of bacteria to topography. These results may help in the search for the best topographies for osteoblast behavior and for the inhibition of bacterial colonization.

The Influence of Health Behavior on Immediate Loading Implant Success and Patient Satisfaction In The Complete Edentulous Treatment

Objective: The cases of edentulous treatment are increasing in Turkey. The patients are less satisfied with the health care facilities of the public sector health institutes. The government of Turkey is facing critical challenges for medical reforms in the public sector to improve the living standards of the public. The objective of current research is to determine the influence of health behavior on immediate loading implant success and patient satisfaction in complete edentulous treatment. Method: A Likert scale questionnaire is employed and the response rate of this research is 71%. The population of this research is the patients visiting different clinics for edentulous treatment and loading implant success. Results: The research findings demonstrate the satisfaction of the patients and implant success is influenced by the health behavior of patients. Conclusion: The model of this research is enrichment in the knowledge of the edentulous treatment of the patients. The practical implications of this research are outstanding to influence the satisfaction of the edentulous treatment patients who are getting the treatment of loading implant success. The research has certain limitations that are straightforwardly presented with future directions to enrich the knowledge of edentulous treatment by the research work of scholars in health care.

Immediate Functional Loading with Full-Arch Fixed Implant-Retained Rehabilitation in Periodontal Patients: Clinical Study

(1) Background. The immediate functional loading of implants is a clinical procedure used for treating periodontal edentulous patients. This clinical study aimed to evaluate the clinical outcomes of the immediate functional loading of implants with fully fixed rehabilitations in compromised periodontal patients. (2) Methods. Three hundred and five implants IPX screw implants were placed in 27 periodontal patients using an immediate functional loading protocol with fixed rehabilitations. All patients had a previous history of periodontitis, four patients (14.8%) were smokers and seven patients (25.9%) suffered from chronic medical conditions. (3) Results. Implant and prosthetic clinical findings were evaluated during a mean period of 41.3 ± 19.6 months. No implants were lost during the clinical follow-up. The cumulative survival rate for all implants was 100%. Regarding the prostheses designed, a total of 54 fixed prostheses were placed in the 27 patients immediately after the surgery. Forty-four hybrid fixed prostheses (81.5%) and 10 fixed rehabilitations (18.5%) were placed in the patients. The mean marginal bone loss was 1.51 ± 1.16 mm, ranging from 0 to 3.5 mm during the follow-up evaluation. Thirty-one implants (10.2%) in 10 patients (37%) were associated with peri-implantitis. Five patients (18.5%) showed some kind of technical complications (loss/fracture of the prosthetic screw, acrylic resin fracture, ceramic chipping). (4) Conclusions. The clinical outcomes of this study demonstrate that fixed rehabilitation by immediate functional loading of implants is considered a predictable procedure.

Implications of considering peri-implant bone loss a disease, a narrative review

BACKGROUND

Peri-implantitis has been suggested to cause significant increasing proportions of implant failure with increasing time.

PURPOSE

To assess whether implant failure rates in long term studies are matching the supposed high prevalence of peri-implantitis.

MATERIAL AND METHODS

This paper is written as a narrative review of the long-term clinical investigations available in the literature.

RESULTS

Some implant systems have seen unacceptable marginal bone loss figures with time coupled to increased implant failure rates, resulting in the withdrawal of these systems. The reasons for such mishap are generally unknown, with the exception of one system failure that was found to be due to improper clinical handling. Modern, moderately rough implant systems have functioned excellently over 10-15 years of follow up with minor problems with marginal bone loss and implant failure rates within a few per cent. Machined implants have functioned adequately over 20-30 years of follow up. Implant failures occur predominantly during the first few years after implant placement. No significant increase of implant failures has been observed thereafter over 20-30 years of follow up. Over the years of our new millennium, scientific and technical advances have allowed the discovery of numerous molecular pathways and cellular interactions between the skeletal and immune system promoting the development of the interdisciplinary field called osteoimmunology. Nowadays, this knowledge has not only allowed the emergence of new etiologic paradigms for bone disease but also a new dynamic approach on the concept of osseointegration and MBL around oral implants, re-evaluating our older disease oriented outlook. This facilitates at the same time the emergence of translational applications with immunological perspectives, scientific approaches based on omics sciences, and the beginning of an era of personalized dental implant therapy to improve the prognosis of oral implant treatment.

CONCLUSIONS

Oral implant systems have been found to function with very good clinical outcome over follow-up times of 20-30 years. Registered implant failures have occurred predominantly during the first few years after implantation, and there has been no significant increase in late failures due to peri-implantitis.

Long-Term Treatment Outcomes of Implant Prostheses in Partially and Totally Edentulous Patients

Implant dental therapy is a clinical procedure used for treating patients with tooth loss with known clinical success. This clinical study aimed to evaluate the long-term clinical outcomes of dental implants in partially and totally edentulous patients. A total of 544 Microdent (Microdent SU, Implant Microdent System®, Santa Eulàlia de Ronçana Barcelona, Spain) screw implants were placed in 111 patients using a two-stage surgical technique and a conventional loading protocol (lasting 3 months). Implant and prosthetic clinical findings were evaluated during a 15-year follow-up. A total of 6 implants were lost during the healing period, and 124 prostheses were placed over the 538 implants that remained: 20 single crowns, 52 partially fixed bridges, 45 full-arch fixed restorations, and 7 overdentures. A total of 20 of these were lost during the follow-up period. The cumulative survival rate for all implants was 96.4%. The data underwent statistical analysis (significance level: p < 0.05). The mean marginal bone loss was 1.82 ± 0.54 mm, ranging from 1.2 to 3.1 mm. The most frequent complications were mechanical prosthodontic complications (16.2%). In all, 11.8% of implants showed periimplantitis as the primary biological complication. Dental implants inserted in both the maxillary and mandibular areas produce long-term favorable outcomes and stable tissue conditions when a delayed loading protocol is followed.

Effects of Osseodensification on Immediate Implant Placement: Retrospective Analysis of 211 Implants

Osseodensification is a new method of bone instrumentation for dental implant placement that preserves bulk bone and increases primary implant stability, and may accelerate the implant rehabilitation treatment period and provide higher success and survival rates than conventional methods. The aim of this retrospective study was to evaluate and discuss results obtained on immediate implant placement with immediate and delayed loading protocols under Osseodensification bone instrumentation. This study included private practice patients that required dental implant rehabilitation, between February 2017 and October 2019. All implants were placed under Osseodensification and had to be in function for at least 12 months to be included on the study. A total of 211 implants were included in the study, with a 98.1% total survival rate (97.9% in the maxilla and 98.5% in the mandible). For immediate implants with immediate load, 99.2% survival rate was achieved, and 100% survival rate for immediate implant placement without immediate load cases. A total of four implants were lost during this period, and all of them were lost within two months after placement. Within the limitations of this study, it can be concluded that Osseodensification bone instrumentation provided similar or better results on survival rates than conventional bone instrumentation.

Three interfaces of the dental implant system and their clinical effects on hard and soft tissues

Anatomically, the human tooth has structures both embedded within and forming part of the exterior surface of the human body. When a tooth is lost, it is often replaced by a dental implant, to facilitate the chewing of food and for esthetic purposes. For successful substitution of the lost tooth, hard tissue should be integrated into the implant surface. The microtopography and chemistry of the implant surface have been explored with the aim of enhancing osseointegration. Additionally, clinical implant success is dependent on ensuring that a barrier, comprising strong gingival attachment to an abutment, does not allow the infiltration of oral bacteria into the bone-integrated surface. Epithelial and connective tissue cells respond to the abutment surface, depending on its surface characteristics and the materials from which it is made. In particular, the biomechanics of the implant-abutment connection structure (i.e., the biomechanics of the interface between implant and abutment surfaces, and the screw mechanics of the implant-abutment assembly) are critical for both the soft tissue seal and hard tissue integration. Herein, we discuss the clinical importance of these three interfaces: bone-implant, gingiva-abutment, and implant-abutment.

Clinical and Radiological Outcomes for Guided Implant Placement in Sites Preserved with Bioactive Glass Bone Graft after Tooth Extraction: A Controlled Clinical Trial

The goal of the study was to evaluate marginal bone loss (MBL) after 1-year implant placement using a guided implant surgical (GIS) protocol in grafted sockets compared to non-grafted sites. We followed a parallel study design with patients divided into two groups: grafted group (Test group, n = 10) and non-grafted group (Control, n = 10). A bioactive glass bone graft was used for grafting. A single edentulous site with a minimum bone height ≥11 mm and bone width ≥6 mm confirmed by cone-beam computerized tomography (CBCT) was chosen for implant placement. Tapered hybrid implants that were sandblasted and acid-etched (HSA) were placed using the GIS protocol and immediately loaded with a provisional prosthesis. MBL and implant survival rates (ISR) were assessed based on standardized radiographs and clinical exams. Patients were followed up for 1-year post-loading. MBL after one year, in the control group, was −0.31 ± 0.11 mm (mesial) and −0.28 ± 0.09 mm (distal); and in the test group was −0.35 ± 0.11 mm (mesial) and −0.33 ± 0.13 mm (distal), with no statistical significance (p > 0.05). ISR was 100% in both groups after one year. ISR was similar between groups and the marginal bone changes were comparable one year after functional loading, without statistical significance, suggesting that bioactive glass permitted adequate bone formation. The GIS protocol avoided raising flaps and provided a better position to place implants, preserving the marginal bone around implants.

Latest Trends in Surface Modification for Dental Implantology: Innovative Developments and Analytical Applications

An increase in the world population and its life expectancy, as well as the ongoing concern about our physical appearance, have elevated the relevance of dental implantology in recent decades. Engineering strategies to improve the survival rate of dental implants have been widely investigated, focusing on implant material composition, geometry (usually guided to reduce stiffness), and interface surrounding tissues. Although efforts to develop different implant surface modifications are being applied in commercial dental prostheses today, the inclusion of surface coatings has gained special interest, as they can be tailored to efficiently enhance osseointegration, as well as to reduce bacterial-related infection, minimizing peri-implantitis appearance and its associated risks. The use of biomaterials to replace teeth has highlighted the need for the development of reliable analytical methods to assess the therapeutic benefits of implants. This literature review considers the state-of-the-art strategies for surface modification or coating and analytical methodologies for increasing the survival rate for teeth restoration.

Implant Treatment by Guided Surgery Supporting Overdentures in Edentulous Mandible Patients

INTRODUCTION

This study aimed to show the clinical outcomes of implants inserted by guided surgery supporting mandibular overdentures in edentulous patients.

PATIENTS AND METHODS

Mandibular edentulous patients were diagnosed with an oral examination, cone-beam computerized tomography, and diagnostic casts for intermaxillary relations and treated with overdentures over two implants by guided surgery. After flapless surgery, implants were early loaded with an overdenture at 6 weeks.

RESULTS AND DISCUSSION

Fourteen patients (nine females and five males) were treated with 28 implants. Four patients (28.6%) had a previous history of periodontitis. Five patients (35.7%) were smokers. Nine patients (64.3%) suffered from systemic diseases (i.e., diabetes, cardiovascular diseases). The clinical follow-up of the study was 44.7 ± 31.4 months. Clinical outcomes showed a global success of 100% of implants. Fourteen overdentures were placed in the patients over the implants. Mean marginal bone loss was 1.25 mm ± 0.95 mm. Four patients (28.6%) showed some kind of mechanical prosthodontic complications. Six implants (21.4%) were associated with peri-implantitis.

CONCLUSIONS

This study indicates that treatment of mandibular edentulous patients with overdentures by guided surgery and early loading of implants placed appears to be a successful implant protocol.

Mechanical Properties and Corrosion Behavior of Ti6Al4V Particles Obtained by Implantoplasty: An In Vitro Study. Part II

In the field of implant dentistry there are several mechanisms by which metal particles can be released into the peri-implant tissues, such as implant insertion, corrosion, wear, or surface decontamination techniques. The aim of this study was to evaluate the corrosion behavior of Ti6Al4V particles released during implantoplasty of dental implants treated due to periimplantitis. A standardized protocol was used to obtain metal particles produced during polishing the surface of Ti6Al4V dental implants. Physicochemical and biological characterization of the particles were described in Part I, while the mechanical properties and corrosion behavior have been studied in this study. Mechanical properties were determined by means of nanoindentation and X-ray diffraction. Corrosion resistance was evaluated by electrochemical testing in an artificial saliva medium. Corrosion parameters such as critical current density (icr), corrosion potential (E_CORR), and passive current density (i_CORR) have been determined. The samples for electrochemical behavior were discs of Ti6Al4V as-received and discs with the same mechanical properties and internal stresses than the particles from implantoplasty. The discs were cold-worked at 12.5% in order to achieve the same properties (hardness, strength, plastic strain, and residual stresses). The implantoplasty particles showed a higher hardness, strength, elastic modulus, and lower strain to fracture and a compressive residual stress. Resistance to corrosion of the implantoplasty particles decreased, and surface pitting was observed. This fact is due to the increase of the residual stress on the surfaces which favor the electrochemical reactions. The values of corrosion potential can be achieved in normal conditions and produce corroded debris which could be cytotoxic and cause tattooing in the soft tissues.

Clinical Evaluation of Dental Implants with a Double Acid-Etched Surface Treatment: A Cohort Observational Study with Up to 10-Year Follow-Up

BACKGROUND AND OBJECTIVES

The main purpose of this study was to evaluate the survival and success rates of dental implants with a double acid-etched surface treatment with evaluation times up to 10 years post-loading. Materials and Methods: This study was conducted at a hospital oral surgery and implantology unit. It included 111 dental implants with a double acid-etched surface. Three groups were created: Group 1 (1-3 years loading), Group 2 (3-5 years loading), and Group 3 (over 5 years loading). Probing depth, resonance frequency analysis (ISQ value), and marginal bone loss were evaluated. Results: The data obtained underwent statistical analysis. Overall, 78 patients were included in the study, who received, in total, 111 dental implants, all replacing single teeth. Mean probing depth was 3.03 mm and mean ISQ was 65.54. Regarding marginal bone loss, in Group 1, 67.6% of implants did not undergo any thread loss, in Group 2, 48.3%, and in Group 3, 59.6%; 59.10% of all implants did not present thread loss with a mean bone loss of 0.552 mm. The implant survival rate was 99.1%, and the success rate was 96.37%. Conclusions: Implants with a double acid-etched surface showed excellent success rates in terms of marginal bone loss, ISQ, and probing depth after up to 10 years of loading, making them a clinically predictable treatment option. Future studies are needed to compare this implant surface with other types in different restorative situations.

Osseointegration of Sandblasted and Acid-Etched Implant Surfaces. A Histological and Histomorphometric Study in the Rabbit

Titanium surface is an important factor in achieving osseointegration during the early wound healing of dental implants in alveolar bone. The purpose of this study was to evaluate sandblasted-etched surface implants to investigate the osseointegration. In the present study, we used two different types of sandblasted-etched surface implants, an SLA™ surface and a Nanoblast Plus™ surface. Roughness and chemical composition were evaluated by a white light interferometer microscope and X-ray photoelectron spectroscopy, respectively. The SLA™ surface exhibited the higher values (Ra 3.05 μm) of rugosity compared to the Nanoblast Plus™ surface (Ra 1.78 μm). Both types of implants were inserted in the femoral condyles of ten New Zealand white rabbits. After 12 weeks, histological and histomorphometric analysis was performed. All the implants were osseointegrated and no signs of infection were observed. Histomorphometric analysis revealed that the bone–implant contact % (BIC) ratio was similar around the SLA™ implants (63.74 ± 13.61) than around the Nanoblast Plus™ implants (62.83 ± 9.91). Both implant surfaces demonstrated a favorable bone response, confirming the relevance of the sandblasted-etched surface on implant osseointegration.

Mineralization of Titanium Surfaces: Biomimetic Implants

The surface modification by the formation of apatitic compounds, such as hydroxyapatite, improves biological fixation implants at an early stage after implantation. The structure, which is identical to mineral content of human bone, has the potential to be osteoinductive and/or osteoconductive materials. These calcium phosphates provoke the action of the cell signals that interact with the surface after implantation in order to quickly regenerate bone in contact with dental implants with mineral coating. A new generation of calcium phosphate coatings applied on the titanium surfaces of dental implants using laser, plasma-sprayed, laser-ablation, or electrochemical deposition processes produces that response. However, these modifications produce failures and bad responses in long-term behavior. Calcium phosphates films result in heterogeneous degradation due to the lack of crystallinity of the phosphates with a fast dissolution; conversely, the film presents cracks, which produce fractures in the coating. New thermochemical treatments have been developed to obtain biomimetic surfaces with calcium phosphate compounds that overcome the aforementioned problems. Among them, the chemical modification using biomineralization treatments has been extended to other materials, including composites, bioceramics, biopolymers, peptides, organic molecules, and other metallic materials, showing the potential for growing a calcium phosphate layer under biomimetic conditions.

Preservation of alveolar ridge height through mechanical memory: A novel dental implant design

Irreversible marginal bone loss can hinder recovery around dental implants. Insufficient alveolar osteogenesis and stress concentration during chewing contribute to marginal bone resorption and can result in implant failure. A biomaterial with a micropore-channel structure was developed using 3D printing technology. This design facilitated bony ingrowth and provided similar mechanical stimulation at the implant neck during mastication to a natural tooth. The micropore channels provided a guiding structure for bone mesenchymal stem cell proliferation and differentiation without the need for growth factors. Specifically, this was achieved through mechanical transduction by F-actin remodeling and the activation of Yes-associated protein (YAP). The implants were verified in a canine dental implant surgery model, which demonstrated the promising use of biomaterial-based dental implants in future clinical applications.