A randomized, controlled, clinical study on a new titanium oxide abutment surface for improved healing and soft tissue health

Effect of Repeated Moist Heat Sterilization on Titanium Implant-Abutment Interface-An In Vitro Study

OBJECTIVES

 Sterilization eliminates microbial viability by decreasing the biological load, but likewise have the ability to deteriorate the mechanical properties of an implant material. This study intended to evaluate the effect of repeated moist heat sterilization on implant-abutment interface using two different implant systems.

MATERIALS AND METHODS

 Forty screw-retained titanium implant-abutment combinations (fixture 3.5 ×10 mm, abutment 2 mm diameter), twenty each from Genesis (Aktiv Implant Systems, United States) and Bredent (SKY, Germany), were divided into four different groups (n = 10) and placed in a computer-aided diagnostic model. The abutments from each group were exposed to first and second autoclave cycle (121°C for 30 minutes), connected back to the fixture and analyzed under scanning electron microscope for marginal gap and surface roughness.

RESULTS

 Genesis group showed higher marginal gaps on both sides (buccal/mesial [2.8 ± 0.47]; lingual/distal [2.8 ± 0.33]), while Bredent implant-abutment system (IAS) did not show any changes in marginal gaps after autoclaving. Differences within and between the group were found to be statistically significant. Surface roughness for Genesis (243.7 ± 70.30) and Bredent groups (528.9 ± 213.19) was highest at second autoclave, with Bredent implant-abutment showing higher values for surface roughness than Genesis IAS.

CONCLUSION

 Marginal vertical gap increased with autoclaving for Genesis IAS, while Bredent implant abutments were more stable. Surface roughness increases with autoclaving for both Genesis and Bredent group of IAS.

Surface Topography Steer Soft Tissue Response and Antibacterial Function at the Transmucosal Region of Titanium Implant

Metallic dental implants have been extensively used in clinical practice due to their superior mechanical properties, biocompatibility, and aesthetic outcomes. However, their integration with the surrounding soft tissue at the mucosal region remains challenging and can cause implant failure due to the peri-implant immune microenvironment. The soft tissue integration of dental implants can be ameliorated through different surface modifications. This review discussed and summarized the current knowledge of topography-mediated immune response and topography-mediated antibacterial activity in Ti dental implants which enhance soft tissue integration and their clinical performance. For example, nanopillar-like topographies such as spinules, and spikes showed effective antibacterial activity in human salivary biofilm which was due to the lethal stretching of bacterial membrane between the nanopillars. The key findings of this review were (I) cross-talk between surface nanotopography and soft tissue integration in which the surface nanotopography can guide the perpendicular orientation of collagen fibers into connective tissue which leads to the stability of soft tissue, (II) nanotubular array could shift the macrophage phenotype from pro-inflammatory (M1) to anti-inflammatory (M2) and manipulate the balance of osteogenesis/osteoclasia, and (III) surface nanotopography can provide specific sites for the loading of antibacterial agents and metallic nanoparticles of clinical interest functionalizing the implant surface. Silver-containing nanotubular topography significantly decreased the formation of fibrous encapsulation in per-implant soft tissue and showed synergistic antifungal and antibacterial properties. Although the Ti implants with surface nanotopography have shown promising in targeting soft tissue healing in vitro and in vivo through their immunomodulatory and antibacterial properties, however, long-term in vivo studies need to be conducted particularly in osteoporotic, and diabetic patients to ensure their desired performance with immunomodulatory and antibacterial properties. The optimization of product development is another challenging issue for its clinical translation, as the dental implant with surface nanotopography must endure implantation and operation inside the dental microenvironment. Finally, the sustainable release of metallic nanoparticles could be challenging to reduce cytotoxicity while augmenting the therapeutic effects.

Effect of TiO2 Abutment Coatings on Peri-Implant Soft Tissue Behavior: A Systematic Review of In Vivo Studies

Establishing a proper soft tissue adhesion around the implant abutment is essential to prevent microbial invasion, inhibit epithelial downgrowth, and obtain an optimal healing process. This systematic review aims to evaluate the real potential of TiO2 coating on the behavior of peri-implant soft tissue health and maintenance. A specific aim was to evaluate clinically and histologically the effect of TiO2 abutment coating on epithelial and connective tissue attachment. Electronic database searches were conducted from 1990 to 2023 in MEDLINE/PubMed and the Web of Science databases. In total, 15 out of 485 publications were included. Eight studies involved humans, and seven were animal studies. Exposure time ranges from 2 days to 5 years. The peri-implant soft tissue evaluations included clinical assessment (plaque index (PI), peri-implant probing pocket depth (PPD), and bleeding on probing (BoP)), histological as well as histomorphometric analysis. The Office of Health Assessment and Translation (OHAT) Risk of Bias Rating Tool for Human and Animal Studies was used to evaluate the overall quality of the studies included in the review. The results showed some variation but remained within acceptable limits. Within the limitations of this systematic review, the present findings suggest that TiO2 coatings seem to influence soft tissue healing. TiO2-coated abutments with a roughness value between 0.2 and 0.5 μm enhance soft tissue health. Sol-gel-derived TiO2 coatings induced better soft tissue attachment than noncoated machined abutment surfaces. The anodized titanium abutments demonstrate comparable clinical and histological outcomes to conventional machined abutments. However, there was variation among the included studies concerning TiO2 coating characteristics and the measured outcomes used to evaluate the soft tissue response, and therefore, quantitative analysis was not feasible. Long-term in vivo studies with standardized soft tissue analysis and coating surface parameters are necessary before a definitive conclusion can be drawn. OSF Registration No.: 10.17605/OSF.IO/E5RQV.

Influence of surface nanotopography and wettability on early phases of peri-implant soft tissue healing: an in-vivo study in dogs

BACKGROUND

It is well established that nanotopography and wettability of implant surfaces contribute to osseointegration and long-term implant success. However, the effects of a hydrogenated surface with nanotubular and superhydrophilic properties on peri-implant soft tissue remain unclear. This study was designed to study the impact of a modified abutment surface on early soft tissue integration compared with a machined surface.

METHODS

Thirty-six implants were placed at the bone level in the bilateral mandible of six beagles, followed by healing abutments belonging to the standard machined Ti-6Al-4V alloy abutments (TC4-M), anodized abutments with nanotubes (TC4-Nano), and hydrogenated abutments (TC4-H/Nano) groups, which were randomly screwed to the implants. After two and four weeks of wound healing, the animals were euthanized for histological evaluation.

RESULTS

A superhydrophilic nanotubular surface developed on the hydrogenated abutment. Histological and histometric analyses revealed similar peri-implant soft tissue healing and dimensions for the three types of abutments at two and four weeks. Connective tissue (CT) length was longer around TC4-H/Nano abutments compared with standard abutments; however, the differences were not statistically significant. Moreover, collagen fibers in the TC4-H/Nano group extended and were attached perpendicularly to the superhydrophilic surface.

CONCLUSIONS

Our results revealed that the soft tissue interface adjacent to the hydrogenated abutment is comparable to that of the machined abutment. A tendency of increased CT length and perpendicular collagen fibers was observed around the modified abutment. This study suggests that nanotubular/superhydrophilic surfaces could be a promising modification to enhance soft tissue sealing. However, comprehensive studies should be conducted to evaluate the peri-implant soft tissue around the modified abutment immunohistochemically, histopathologically, and clinically.

Trans-mucosal platforms for dental implants: Strategies to induce muco-integration and shield peri-implant diseases

OBJECTIVES

Trans-mucosal platforms connecting the bone-anchored implants to the prosthetic teeth are essential for the success of oral rehabilitation in implant dentistry. This region promotes a challenging environment for the successfulness of dental components due to the transitional characteristics between soft and hard tissues, the presence of bacteria, and mechanical forces. This review explored the most current approaches to modify trans-mucosal components in terms of macro-design and surface properties.

METHODS

This critical review article revised intensely the literature until July 2023 to demonstrate, discuss, and summarize the current knowledge about marketable and innovative trans-mucosal components for dental implants.

RESULTS

A large number of dental implant brands have promoted the development of several implant-abutment designs in the clinical market. The progress of abutment designs shows an optimistic reduction of bacteria colonization underlying the implant-abutment gap, although, not completely inhibited. Fundamental and preclinical studies have demonstrated promising outcomes for altered-surface properties targeting antibacterial properties and soft tissue sealing. Nanotopographies, biomimetic coatings, and antibiotic-release properties have been shown to be able to modulate, align, orient soft tissue cells, and induce a reduction in biofilm formation, suggesting superior abilities compared to the current trans-mucosal platforms available on the market.

SIGNIFICANCE

Future clinical implant-abutments show the possibility to reduce peri-implant diseases and fortify soft tissue interaction with the implant-substrate, defending the implant system from bacteria invasion. However, the absence of technologies translated to commercial stages reveals the need for findings to "bridge the gap" between scientific evidences published and applied science in the industry.

Influence of Surface Characteristics of TiO2 Coatings on the Response of Gingival Cells: A Systematic Review of In Vitro Studies

The soft tissue-implant interface requires the formation of epithelium and connective tissue seal to hinder microbial infiltration and prevent epithelial down growth. Nanoporous titanium dioxide (TiO₂) surface coatings have shown good potential for promoting soft tissue attachment to implant surfaces. However, the impact of their surface properties on the biological response of gingival cells needs further investigation. This systematic review aimed to investigate the cellular behavior of gingival cells on TiO₂-implant abutment coatings based on in vitro studies. The review was performed to answer the question: "How does the surface characteristic of TiO₂ coatings influence the gingival cell response in in vitro studies?". A search in MEDLINE/PubMed and the web of science databases from 1990 to 2022 was performed using keywords. A quality assessment of the studies selected was performed using the SciRAP method. A total of 11 publications were selected from the 289 studies that fulfilled the inclusion criteria. The mean reporting and methodologic quality SciRAP scores were 82.7 ± 6.4/100 and 87 ± 4.2/100, respectively. Within the limitations of this in vitro systematic review, it can be concluded that the TiO₂ coatings with smooth nano-structured surface topography and good wettability improve gingival cell response compared to non-coated surfaces.

Transmucosal abutments in the esthetic zone: Surgical and prosthetic considerations

OBJECTIVE

This article describes an updated step-by-step protocol for transmucosal abutment selection and treatment sequencing after immediate implant placement in the esthetic zone.

CLINICAL CONSIDERATIONS

Current surgical and prosthetic concepts strive to preserve hard and soft-tissues to provide optimal esthetics at the implant-abutment interface. Consequently, restoring implants in the esthetic zone with transmucosal abutments presents a great challenge and must take into consideration implant depth, angulation, and bucco-lingual position as well as transmucosal height and space for an optimized emergence profile of the restoration and the dimensions of the anterior tooth to be restored. The proper selection of the type, shape, and dimensions of implant components and connections, determined by the product portfolio offered by the implant manufacturer, play a critical role in the ability to adequately address these challenges. This article provides an update on surgical and prosthetic workflows for single implant restorations in the esthetic zone.

CONCLUSIONS

Following esthetic, mechanical, and biologic principles, the long-term success of implant-supported restorations in the esthetic zone is directly correlated to proper execution and sequencing of surgical and prosthetic treatment steps, especially after immediate implant placement. These steps must be critically assessed based on the current scientific evidence to achieve the desired clinical outcomes on a predictable and consistent basis.

CLINICAL SIGNIFICANCE

Selection of surgical and prosthetic treatment protocols to achieve ideal esthetic outcomes and emergence profiles in implant dentistry is often a great challenge, not only determined by technical and clinical skills of the provider but also by the type and dimensions of implant components and connections offered by the manufacturer. Following certain decision-making principles and workflows are key for clinical success with implant-supported restorations after immediate implant placement the esthetic zone.

Preventing Peri-implantitis: The Quest for a Next Generation of Titanium Dental Implants

Titanium and its alloys are frequently the biomaterial of choice for dental implant applications. Although titanium dental implants have been utilized for decades, there are yet unresolved issues pertaining to implant failure. Dental implant failure can arise either through wear and fatigue of the implant itself or peri-implant disease and subsequent host inflammation. In the present report, we provide a comprehensive review of titanium and its alloys in the context of dental implant material, and how surface properties influence the rate of bacterial colonization and peri-implant disease. Details are provided on the various periodontal pathogens implicated in peri-implantitis, their adhesive behavior, and how this relationship is governed by the implant surface properties. Issues of osteointegration and immunomodulation are also discussed in relation to titanium dental implants. Some impediments in the commercial translation for a novel titanium-based dental implant from "bench to bedside" are discussed. Numerous in vitro studies on novel materials, processing techniques, and methodologies performed on dental implants have been highlighted. The present report review that comprehensively compares the in vitro, in vivo, and clinical studies of titanium and its alloys for dental implants.

Race for Applicable Antimicrobial Dental Implant Surfaces to Fight Biofilm-Related Disease: Advancing in Laboratorial Studies vs Stagnation in Clinical Application

Across years, potential strategies to fight peri-implantitis have been notoriously explored through the antimicrobial coating implant surfaces capable of interfering with the bacterial adhesion process. However, although experimental studies have significantly advanced, no product has been marketed so far. For science to reach the society, the commercialization of research outcomes is necessary to provide real advancement in the biomedical field. Therefore, the aim of this study was to investigate the challenges involved in the development of antimicrobial dental implant surfaces to fight peri-implantitis, through a systematic search. Research articles reporting antimicrobial dental implant surfaces were identified by searching PubMed, Scopus, Web of Science, The Cochrane Library, Embase, and System of Information on Grey Literature in Europe, between 2008 and 2020. A total of 1778 studies were included for quality assessment and the review. An impressive number of 1655 articles (93,1%) comprised in vitro studies, whereas 123 articles refer to in vivo investigations. From those 123, 102 refer to animal studies and only 21 articles were published on the clinical performance of antibacterial dental implant surfaces. The purpose of animal studies is to test how safe and effective new treatments are before they are tested in people. Therefore, the discrepancy between the number of published studies clearly reveals that preclinical investigations still come up against several challenges to overcome before moving forward to a clinical setting. Additionally, researchers need to recognize that the complex journey from lab to market requires more than a great idea and resources to develop a commercial invention; research teams must possess the skills necessary to commercialize an invention.

Effect Morphology and Surface Treatment of the Abutments of Dental Implants on the Dimension and Health of Peri-Implant Biological Space

Statement of the problem: The gingival configuration around implant abutments is of paramount importance for preserving the underlying marginal bone, and hence for the long-term success of dental implants. Objective: The objective was to study, clinically and histologically, the effects of the change in the morphology of abutments connected to the endosseous implant, and of their surface treatment. In particular, the objective was to ascertain the effect of changing the shape of the transepithelial pillar and the treatment of its surface on the dimensions, quality and health of the components of the peri-implant biological space, such as the dimensions of the epithelial and connective tissues of the biological space, the concentration of inflammatory cells and the density of collagen fibers. Methods: A clinical trial of 10 patients with a totally edentulous maxilla, who had four implants (IPX4010_GALIMPLANT®, Sarria, Spain) inserted in the area of the first and second molars on both sides with computer-guided implant surgery, was conducted with the final purpose of assessing the quality of the peri-implant soft tissue attachment around the transepithelial abutments which were employed (aesthetic machined (RM), aesthetic anodized (RA), slim machined (SM) and slim anodized (SA)). At 8 weeks and following the collection of the samples (removal of the implant-abutment assembly with its surrounding hard and soft tissue) and their processing for subsequent histological and histomorphometric analysis in order to study the dimensions, quality and health of the peri-implant soft tissue area, the variables previously mentioned were determined according to the aims of the study. By using appropriate diameter trephine in order to obtain a useful fringe of soft tissue around the transepithelial pillars, ANOVA and chi-square tests were performed. Results: The SPSS statistical analysis ANOVA results revealed that the machined slim abutments have a better performance considering the variables analyzed with epithelial and connective attachment heights of 1.52 mm and 2.3 mm, respectively, and that connective density (density of collagen fibers) was high at 85.7% of the sample size affected by the design for the slim abutments and 92.9% of the high-density sample size affected by the surface treatment for the machined surface. Conclusions: All variables studied, despite the small sample size, showed the superiority of the slim machined abutment among the four groups.

Lithium disilicate and peek implant-retained single crowns - a randomized, prospective clinical study

Introduction/Objective. Comparing two materials under the same conditions is the best way to define differences between them. PEEK is a polymer that has many possible uses in dentistry as already well-known lithium disilicate ceramics. The aim of this study was to compare peri-implant soft tissue healing and evaluate patient satisfaction with esthetics in different observation periods, as well as the success and survival rate of both types of crowns. Methods. The study was conducted as a clinical, prospective, randomized split-mouth study on 17 patients with bilaterally missing upper teeth of the same type, replaced with dental implants. Study outcomes have been analyzed with subjective (VAS scale) and objective parameters (MBI, MPI and PPD) baseline, six and twelve months after fixing crowns onto the implants. Results. Comparison of the results between PEEK and lithium disilicate crowns showed no statistical differences in terms of MPI, MBI and PPD in the observed periods. Analyzing MPI during observation periods in the PEEK group of crowns, statistical significance was registered between baseline values and after 6 months. Also, statistical significance was noticed in terms of PPD during the observation time both in the study and control group of crowns. Results for VAS for the esthetics showed no statistically significant difference between the groups, while VAS for restoration satisfaction showed a statistically significant difference. Conclusion. This study showed that scores of the applied subjective and objective parameters can be a reliable tool to rate the clinical outcome of implant-retained single crowns over time.

Effect of anodized titanium abutment collars on peri-implant soft tissue: A split-mouth clinical study

STATEMENT OF PROBLEM

Anodic oxidation of titanium implant abutment collars has been used to mask their unesthetic grayish color. However, the effect of anodic oxidation on the health and appearance of peri-implant soft tissues is unclear.

PURPOSE

The purpose of this split-mouth clinical study was to investigate the effect of anodized titanium on the health and esthetics of peri-implant soft tissues.

MATERIAL AND METHODS

A total of 60 osseointegrated implants placed in 30 participants were included in the present study. Each participant received 2 randomly allocated abutments, one with a pink anodized collar and the other with an unanodized one to form 2 groups: unanodized group (control group) and anodized group (experimental group). All implants were restored with lithium disilicate restorations. Evaluations of the peri-implant soft tissues were performed at the time of definitive restoration insertion (baseline) and after 3, 6, 12, and 18 months: peri-implant probing depth, soft tissue recession, modified sulcus bleeding index, modified plaque index, and modified gingival index. The esthetics of peri-implant soft tissues were evaluated by using the modified pink esthetic score. The paired t test or Wilcoxon signed-rank test was used for comparing the 2 study groups at each point of time depending on the normality of the variables (α=.05). To compare each variable at different time points within each group separately, repeated measures ANOVA or Friedman tests were used according to the normality of the variables, followed by post hoc pairwise comparisons by using the Bonferroni adjusted significance (α=.05).

RESULTS

Five peri-implant soft tissue indices were followed up throughout the study. No statistically significant differences were found among the mean values of the tested indices in the anodized and unanodized groups throughout the evaluation periods (P>.05). The collective mean values of the modified pink esthetic score also showed no statistically significant differences between the groups (P>.05).

CONCLUSIONS

Based on this split-mouth clinical study, pink anodized titanium abutment collars do not produce a clinically significant effect on the health or esthetics of peri-implant soft tissues.

Oral prosthetic microbiology: aspects related to the oral microbiome, surface properties, and strategies for controlling biofilms

The oral cavity is an environment that allows for the development of complex ecosystems; the placement of prosthetic devices as a consequence of partial or total tooth loss may alter the diversity of microbial communities. Biofilms on the surface of materials used in dental prostheses can promote important changes in the mechanic and aesthetic properties of the material itself and may cause local and systemic diseases for the prosthetic wearer. This review presents the main features of the oral microbiome associated with complete or partial dentures and dental implants. The main diseases associated with microbial colonization of prosthetic surfaces, factors that may affect biofilm formation on prosthetic materials, as well as novel alternative therapies aiming to reduce biofilm formation and/or to eradicate biofilms formed on these materials are also explored.

Clinical Performance of Short Expandable Dental Implants for Oral Rehabilitation in Highly Atrophic Alveolar Bone: 3-year Results of a Prospective Single-Center Cohort Study

Background and Objectives: Oral health-related quality of life (OHRQOL) is compromised during the post-implant healing period, especially when vertical augmentation is required. A long-term trial sought to evaluate a short dental implant system with an apically expandable macro-design. Materials and Methods: Over 4.5 years, patients with limited vertical alveolar bone were consecutively recruited into this prospective cohort study. Implant success rate, OHRQOL (Oral Health Impact Profile (OHIP)-14), implant stability, and crestal bone changes were evaluated. Results: Data from 30 patients (mean age: 64.6 years, range 44–83) were analyzed, which related to 104 implants (53 in the maxilla, 51 in the mandible). Over the mean follow-up (42.6 ± 16.4 months), the implant success rate was 94.7% in the mandible (two implants lost) and 83.6% in the maxilla (four implants lost; p = 0.096), and the prosthetic success rate was 100%. The median OHIP-14 scores improved from 23 (interquartile range (IQR) 9–25.5) to 2 (IQR 0–5; p < 0.001). The mean implant stability quotient (ISQ) was 71.2 ± 10.6 for primary stability and 73.7 ± 13.3 (p = 0.213) for secondary stability, without significant maxilla-versus-mandible differences (p ≥ 0.066). Compared to the baseline, median crestal bone changes after loading were 1.0 mm (IQR 0–1.3) and 1.0 mm (IQR 0.2–1.2) in the maxilla and mandible (p = 0.508), respectively, at the end of the first year, 1.1 mm (IQR 0–1.3) and 1.0 mm (IQR 0.1–1.2) (p = 0.382), respectively, at the end of the second year, and 1.2 mm (IQR 0–1.9) and 1.1 mm (IQR 0.1–1.2) (p = 0.304), respectively, at the end of the third year. Conclusions: In patients with limited vertical bone height, short implants with optimized macro-design constitute a reliable method for functional rehabilitation, avoiding extensive alveolar bone augmentation.

Titanium abutment surface modifications and peri-implant tissue behavior: a systematic review and meta-analysis

OBJECTIVES

To evaluate the effect of various titanium abutment modifications on the behaviour of peri-implant soft tissue healing, inflammation and maintenance.

MATERIAL AND METHODS

An electronic database research until 30 April 2019 was performed. A meta-analysis (MA) for each outcome parameter was performed by using the random-effects models with the DerSimonian-Laird estimator.

RESULTS

Ten studies were included in the present review. Four studies with a long follow-up (5-6 years) reported the outcomes in a heterogeneous way and were suitable for MA. Six studies (4 RCT, 2 CCT) including 118 patients and 182 implants dealing with a modified healing abutment surface and short follow-up were selected for MA. The MA for PI and BoP as outcome showed no significant differences between surfaces (PI: P = 0.091; BoP: P = 0.099). The MA for PD as outcome showed no significant differences between surfaces (P = 0.488). No statistical significance was found by evaluating each mixed-effects model for potential moderators (type of study, study design, number of implants, follow-up length). The other four studies with a longer follow-up (5-6 years) reported contradictory results depending on the surface treatment investigated.

CONCLUSIONS

Within their limits, the present findings suggest that peri-implant soft tissue may not be affected by the surface treatment of titanium abutments on the short term. Contrasting results are reported in longer follow-up periods depending on the technique used to modify the abutment.

CLINICAL RELEVANCE

Clinicians should carefully evaluate the use of a modified titanium surface in their practice. Even if no differences in terms of inflammation are present at short term, these findings need to be validated in long-term studies.

Safety and efficacy of a novel anodized abutment on soft tissue healing in Yucatan mini-pigs

BACKGROUND

It is well established that electrochemical anodization of implant surfaces contributes to osseointegration and long-term implant survival. Few studies have investigated its effect on soft tissue healing.

PURPOSE

To evaluate the safety and efficacy of a novel abutment surface prepared by electrochemical oxidation compared to commercially available machined titanium abutments.

MATERIALS AND METHODS

Twelve 16-19 months-old, Yucatan mini-pigs received three dental implants in each mandibular jaw quadrant. Each side was randomized to receive either an anodized or a machined titanium abutment. Titanium healing caps were placed on both abutments. Animals were euthanized at 6 and 13 weeks. Radiographic and histological analyses were performed.

RESULTS

No significant differences were observed histologically between groups in regard to inflammation, epithelium length, mucosal height, bone-to-implant contact, or bone density for any time point. Radiographically, crestal bone level change from baseline to 6 weeks was significantly lower for anodized than machined abutments (P = 0.046); no significant differences were observed at 13 weeks (P = 0.12).

CONCLUSIONS

The novel anodized abutment showed a comparable effect on soft and hard tissue healing/remodeling and inflammation reaction to standard titanium abutments. Clinical studies should confirm these findings and explore the positive radiographic results observed at the early time point.