Breaking the wave of peri-implantitis

Immediate single-tooth implant placement in bony defect sites: A 10-year randomized controlled trial

BACKGROUND

It is unclear whether an intact buccal bony plate is a prerequisite for immediate implant placement in postextraction sockets. The aim of this 10-year randomized controlled trial was to compare peri-implant soft and hard tissue parameters, esthetic ratings of, and patient-reported satisfaction with immediate implant placement in postextraction sockets with buccal bony defects ≥5 mm in the esthetic zone versus delayed implant placement after alveolar ridge preservation.

METHODS

Patients presenting a failing tooth in the esthetic region and a buccal bony defect ≥5 mm after an extraction were randomly assigned to immediate (Immediate Group, n = 20) or delayed (Delayed Group, n = 20) implant placement. The second-stage surgery and provisional restoration placement occurred 3 months after implant placement in both groups, followed by definitive restorations 3 months thereafter. During a 10-year follow-up period, marginal bone levels (primary outcome), buccal bone thickness, soft tissue parameters, esthetics, and patient-reported satisfaction were recorded.

RESULTS

The mean marginal bone level change was -0.71 ± 0.59 mm and -0.36 ± 0.39 mm in the Immediate Group and the Delayed Group after 10 years (p = 0.063), respectively. The secondary outcomes were not significantly different between both groups.

CONCLUSIONS

Marginal bone level changes, buccal bone thickness, clinical outcomes, esthetics, and patients' satisfaction following immediate implant placement, in combination with bone augmentation in postextraction sockets with buccal bony defects ≥5 mm, were not statistically different to those following delayed implant placement after ridge preservation in the esthetic zone.

PLAIN LANGUAGE SUMMARY

Immediate implant placement in case of a failing tooth is a favorable treatment option for patients because it considerably shortens treatment time and the number of surgical treatments. The question is if an intact buccal bone wall is necessary for immediate implant placement. A 10-year study was performed in which 20 patients with a failing tooth in the frontal region of the upper jaw were treated with immediate implant placement and were compared with 20 patients in whom a more conventional treatment strategy was followed in which the failing tooth was first removed and the bone gap restored and the implant placed in a second step. After a 10-year follow-up period, it appeared that the bone around the implant was very stable, gums were healthy, and patients were very satisfied with the result. There was no difference between the two treatment procedures. Such results mean that professionals can discuss the procedure with the patient and apply the individual's preference.

Guided tooth autotransplantation of a palatally impacted maxillary canine into the site of a failed maxillary canine implant

The aim of this report is to demonstrate the guided tooth autotransplantation of a palatally impacted maxillary canine into the site of a failed maxillary canine dental implant. A 47-year-old woman visited a dental clinic complaining of loose dental implant in the left maxillary canine site, tooth #11, as well as pain and swelling of the gum around the implant. The clinical examination revealed a mobile implant along with swollen soft tissues with bleeding on probing. A periapical radiograph demonstrated peri-implant marginal bone loss. Cone beam computed tomography sections revealed that tooth #11 was impacted palatally. The implant was removed and replaced with the impacted canine via guided autotransplantation and posterior orthodontic alignment. The patient was recalled at 1, 3, 6, 9, 12, 24 and 48 months after the procedure. During this period, the patient was symptom-free and radiographic examination at 2 years revealed no periapical pathosis or root resorption.

Evaluation of the effect of adjunctive diode laser application on peri-implant crevicular fluid biomarker levels: a randomized controlled trial

OBJECTIVES

To assess both the clinical and immunological effectiveness of diode laser therapy when used as an adjunct to non-surgical mechanical therapy in managing peri-implantitis.

MATERIALS AND METHODS

A cohort of 27 participants, comprising 21 females and 6 males, agreed to take part in this investigation. 37 dental implants with peri-implantitis diagnosis were randomly allocated to either the laser group (n = 19) or the control group (n = 18). Evaluation of peri-implant clinical parameters and collection peri-implant crevicular fluid (PICF) samples occurred at baseline, as well as at 3 and 6-month follow-up intervals. The level of various biomarkers (TWEAK, IL-1β, sclerostin, IL-17, RANKL, OPG and IL-10) within the PICF were quantified using enzyme-linked immunosorbent assay.

RESULTS

Significant time-dependent decreases in clinical and biochemical parameters were detected in both groups compared to the baseline. There were marked differences between the groups in terms of periodontal parameters, except probing depth, and IL-1β, IL-17, sclerostin levels in PICF at 3rd month follow-up. However, no statistically significant difference was detected at 6th month.

CONCLUSIONS

Diode laser seems to be a reliable tool as an adjunct for supporting the nonsurgical mechanical treatment during the early stages of peri-implantitis. Furthermore, the findings suggest that IL-17, sclerostin and IL-1β may serve as promising biomarkers for assessing efficacy of peri-implantitis treatment.

CLINICAL RELEVANCE

Based on these outcomes, clinicians may consider the application of adjunctive use of diode laser to non-surgical peri-implantitis treatment to achieve better clinical and immunological improvements than nonsurgical peri-implantitis therapy alone in just early healing period. However, it should be noted that there was no difference between the two methods in the long term.

Effectiveness of antimicrobial photodynamic therapy in the treatment of peri-implantitis: systematic review and meta-analysis

The purpose of this study was to evaluate the current scientific evidence on the effectiveness of antimicrobial photodynamic therapy (aPDT) as an adjunctive treatment to mechanical debridement in the treatment of peri-implantitis. The Preferred Reporting Items for Systematic Reviews and Meta-analyses was followed. A protocol was registered in the International Prospective Registry of Systematic Reviews (PROSPERO #CRD42022361684). The search was carried out in seven databases, with no restrictions regarding language or year of publication. Our work included studies that compared clinical periodontal parameters between individuals treated with mechanical debridement associated with aPDT and a control group of patients who had undergone mechanical debridement alone. Study selection, data extraction, and risk of bias assessment (RoB 2.0) were performed by two review authors. Meta-analysis was performed. The mean difference (MD) and a 95% confidence interval (CI) were provided. Four hundred and seven-four studies were identified, of which five studies were included. The meta-analysis demonstrated that aPDT adjunctive to mechanical debridement in subjects with peri-implantitis resulted in greater reduction in probing depth 3 months after treatment than among subjects receiving treatment with mechanical debridement. Most of the included studies exhibit a low risk of bias. Adjunctive aPDT to mechanical debridement contributes to the improvement of peri-implant clinical parameters in individuals with peri-implantitis, in particular probing depth.

Microbial Leakage through Three Different Implant-Abutment Interfaces on Morse Taper Implants In Vitro

The objective of this study was to evaluate microbial leakage by means of genome counts, through the implant-abutment interface in dental implants with different Morse taper abutments. Fifty-six samples were prepared and divided in four groups: CMC TB (14 Cylindrical Implants-14 TiBase Abutments), CMX TB (14 Conical Implants-14 TiBase Abutments), CMX PU (14 Conical Implants-14 Universal Abutment) and CMX U (14 Tapered Implants-14 UCLA Abutments). Assemblies had their interface submerged in saliva as the contaminant. Samples were subjected either to thermomechanical cycling (2 × 106 mechanical cycles with frequency of 5 Hz and load of 120 N simultaneously with thermal cycles of 5-55 °C) or thermal cycling (5-55 °C). After cycling, the contents from the inner parts of assemblies were collected and analyzed using the Checkerboard DNA-DNA hybridization technique. Significant differences in the total genome counts were found after both thermomechanical or thermal cycling: CMX U > CMX PU > CMX TB > CMC TB. There were also significant differences in individual bacterial counts in each of the groups (p < 0.05). Irrespective of mechanical cycling, the type of abutment seems to influence not only the total microbial leakage through the interface, but also seems to significantly reflect differences considering individual target species.

Advances in biomaterials for oral-maxillofacial bone regeneration: spotlight on periodontal and alveolar bone strategies

The intricate nature of oral-maxillofacial structure and function, coupled with the dynamic oral bacterial environment, presents formidable obstacles in addressing the repair and regeneration of oral-maxillofacial bone defects. Numerous characteristics should be noticed in oral-maxillofacial bone repair, such as irregular morphology of bone defects, homeostasis between hosts and microorganisms in the oral cavity and complex periodontal structures that facilitate epithelial ingrowth. Therefore, oral-maxillofacial bone repair necessitates restoration materials that adhere to stringent and specific demands. This review starts with exploring these particular requirements by introducing the particular characteristics of oral-maxillofacial bones and then summarizes the classifications of current bone repair materials in respect of composition and structure. Additionally, we discuss the modifications in current bone repair materials including improving mechanical properties, optimizing surface topography and pore structure and adding bioactive components such as elements, compounds, cells and their derivatives. Ultimately, we organize a range of potential optimization strategies and future perspectives for enhancing oral-maxillofacial bone repair materials, including physical environment manipulation, oral microbial homeostasis modulation, osteo-immune regulation, smart stimuli-responsive strategies and multifaceted approach for poly-pathic treatment, in the hope of providing some insights for researchers in this field. In summary, this review analyzes the complex demands of oral-maxillofacial bone repair, especially for periodontal and alveolar bone, concludes multifaceted strategies for corresponding biomaterials and aims to inspire future research in the pursuit of more effective treatment outcomes.

Metabolic profiling of peri-implant crevicular fluid in peri-implantitis

OBJECTS

This study aims to explore the etiology of peri-implantitis by comparing the metabolic profiles in peri-implant crevicular fluid (PICF) from patients with healthy implants (PH) and those with peri-implantitis (PI).

MATERIALS AND METHODS

Fifty-six patients were enrolled in this cross-sectional study. PICF samples were collected and analyzed using both non-targeted and targeted metabolomics approaches. The relationship between metabolites and clinical indices including probing depth (PD), bleeding on probing (BOP), and marginal bone loss (MBL) was examined. Additionally, submucosal microbiota was collected and analyzed using 16S rRNA gene sequencing to elucidate the association between the metabolites and microbial communities.

RESULTS

Significant differences in metabolic profiles were observed between the PH and PI groups, with 179 distinct metabolites identified. In the PI group, specific amino acids and fatty acids were significantly elevated compared to the PH group. Organic acids including succinic acid, fructose-6-phosphate, and glucose-6-phosphate were markedly higher in the PI group, showing positive correlations with mean PD, BOP, and MBL. Metabolites that increased in the PI group positively correlated with the presence of Porphyromonas and Treponema and negatively with Streptococcus and Haemophilus.

CONCLUSIONS

This study establishes a clear association between metabolic compositions and peri-implant condition, highlighting enhanced metabolite activity in peri-implantitis. These findings open avenues for further research into metabolic mechanisms of peri-implantitis and their potential therapeutic implications.

The role of oxidative stress biomarkers in the development of peri-implant disease: A systematic review and meta-analysis

OBJECTIVES

To analyze the role of oxidative stress (OS) biomarkers in peri‑implant diseases using a systematic review and meta-analysis approach. DATE: The review incorporated cross-sectional studies, randomized controlled trials, and case-control trials to evaluate the differences in OS biomarkers of peri‑implant disease.

SOURCES

A comprehensive literature search was conducted in electronic databases such as PubMed, Scopus, Embase, Web of Science, and CNKI, and no restrictions were applied during the search process.

STUDY SELECTION

A total of 452 studies were identified, of which 18 were eligible for inclusion. Risk of bias and sensitivity analysis were assessed using Egger's test and funnel plots.

RESULTS

We found that the levels of glutathione peroxidase (GSH-Px) in the peri‑implant sulcus fluid (PISF) of patients with peri‑implant diseases were significantly reduced (SMD = -1.40; 95 % CI = 1.70, -1.11; p < 0.001), while the levels of total myeloperoxidase (MPO) and malondialdehyde (MDA) were significantly increased (SMD = 0.46; 95 % CI = 0.12, 0.80; p = 0.008; SMD = 0.28; 95 % CI = 0.01, 0.56; p = 0.043). However, there were no significant differences of MPO concentration (SMD = 0.38; 95 % CI = -0.39, 1.15; p = 0.331) and superoxide dismutase (SOD)(SMD = -0.43; 95 % CI = -1.94, 1.07; p = 0.572) in PISF between peri‑implant disease group and control group. Similarly, salivary MPO did not show significant differences (SMD = 1.62; 95 % CI = -1.01, 4.24; p = 0.227).

CONCLUSIONS

Our results supported that the level of local OS biomarkers was closely related to peri‑implant diseases. GSH-Px, total MPO and MDA may be PISF biomarkers with good capability to monitor the development of peri‑implant disease.

CLINICAL SIGNIFICANCE

This study found significant differences in the levels of local OS biomarkers (GSH-Px, total MPO, and MDA) between patients with peri‑implant diseases and healthy subjects, which may be ideal candidate biomarkers for predicting and diagnosing peri‑implant diseases.

The past forty-three years of dental implantology literature. A global mapping and scientometric analysis

PURPOSE

The aim of this research is to make a scientometric analysis of the dental implantology literature and to present the results in a more understandable way to the reader by visualizing them with maps.

METHODS

The dental implantology literature was accessed through the Web of Science database. Scientometric data was obtained with Citespace 6.1 software, co-citation, clustering analysis, citation burst, and mapping analyzes were performed. Scimago Graphica software was used for additional visualizations.

RESULTS

A total of 35,704 articles were included in the analysis. There were 88,616 authors, 72,333 institutes, 142 countries/regions, and 3,265 journals contributing to the dental implantology literature. The United States was first with 7,334 publications and 225,868 citations. The literature between 1980 and 2023 was divided into 19 different clusters, and the literature between 2000 and 2023 was divided into 16 different clusters.

CONCLUSIONS

Key themes in the field include the use of autogenous bone, advancements in implant surface technology, and the use of platform switching and intraoral scanners. Emerging topics of interest include esthetic considerations in the treatment of the anterior region, stress distribution, the use of zirconia, and the impact of implant treatment on oral health-related quality of life. With similar scientometric analysis studies to be done in the future, the progress of the literature can be followed on the basis of evidence.

Innovative Bioactive Ca-SZ Coating on Titanium Dental Implants: A Multidimensional Structural and Elemental Analysis

The design of new, biomimetic biomaterials is of great strategic interest and is converging for many applications, including in implantology. This study explores a novel approach to improving dental implants. Although endosseous TA6V alloy dental implants are widely used in oral implantology, this material presents significant challenges, notably the prevalence of peri-implantitis. Therefore, in this study, we investigate a new advance in the design of hybrid medical devices. This involves the design of a Ca-SZ coating deposited by PVD on a TA6V substrate. This approach aims to overcome the inherent limitations of each of these materials, namely TA6V's susceptibility to peri-implantitis on the one hand and zirconia's excessively high Young's modulus compared with bone on the other, while benefiting from their respective advantages, such as the ductility of TA6V and the excellent biocompatibility of zirconia, offering relevant prospects for the design of high-performance implantable medical devices. This study integrates characterisation techniques, focusing on the structural and elemental analysis of the Ca-SZ coating by XRD and TEM. The results suggest that this coating combines a tetragonal structure, a uniform morphology with no apparent defects, a clean interface highlighting good adhesion, and a homogeneous composition of calcium, predisposing it to optimal biocompatibility. All of these findings make this innovative coating a particularly suitable candidate for application in dental implantology.

A Standardized Rat Model to Study Peri-implantitis of Transmucosal Osseointegrated Implants

With the high incidence rate, distinctive implant characteristic and unique infection pattern, peri-implantitis (PI) requires a specially designed implant animal model for the researches on the pathogenesis and treatments. Previous small-animal PI models exhibit variability in implant site selection, design, and surgical procedures resulting in unnecessary tissue damage and less effectivity. Herein, a quantitative-analysis-based standardized rat model for transmucosal PI-related research was proposed. After dissecting the anatomic structures of the rat maxilla, we determined that placing the implant anterior to the molars in the rat maxilla streamlined the experimental period and enhanced animal welfare. We standardized the model by controlling the rat strain, gender, and size. The customized implant and a series of matched surgical instruments were appropriately designed. A clear, step-by-step surgical process was established. These designs ensured the success rate, stability, and replicability of the model. Each validation method confirmed the successful construction of the model. This study proposed a quantitative-analysis-based standardized transmucosal PI rat model with improved animal welfare and reliable procedures. This model could provide efficient in vivo insights to study the pathogenesis and treatments of PI and preliminary screening data for further large-animal and clinical trials.

Dental biomechanics of root-analog implants in different bone types

STATEMENT OF PROBLEM

When implants are applied to restore oral function, the masticatory load on the crown will lead to stress development in all parts of the crown-abutment-implant-bone system. An optimal design of the whole system will be important for sustained function.

PURPOSE

The purpose of this 3-dimensional (3D) finite element analysis (FEA) study was to evaluate the influence of the root-analog implant (RAI) design in molar rehabilitation and bone type.

MATERIAL AND METHODS

Twelve 3D models of single posterior implant-supported restorations were created according to the zirconia implant design (monotype, 2-piece, or RAI) and bone type (D1, D2, D3, and D4, according to the Misch classification). The models were composed of cortical bone, cancellous bone, implant, cement layers, and a monolithic ceramic crown. For the 2-piece zirconia implant model, the titanium base, prosthetic screw, and framework were also designed. All materials were assumed to behave elastically throughout the entire analysis. The bone was fixed, and an axial loading of 600 N was applied to the contacts on the occlusal surface of the crowns. Results for the crown and implant were obtained in maximum principal stress, as well as the von Mises stress for the model and bone microstrain.

RESULTS

High stress concentration was observed at the intaglio surface of the crowns near the loading region. Regardless of the design, the stress trend in the implant was similar, increasing proportionally to the bone type (D1>D2>D3>D4). RAI showed a homogeneous stress field near the values calculated for the conventional designs, but with lower magnitudes. The 2-piece zirconia model showed the highest stress magnitude regardless of the bone type and, therefore, the highest failure risk. All models showed a higher strain in the cortical bone than in the cancellous bone, located predominantly in the cervical region. A strain analysis showed that both conventional implant models presented similar behavior for D1 and D2 bone types, with an increasing difference for D3 and D4. RAI showed the lowest strain regardless of the bone type.

CONCLUSIONS

Root-analog zirconia implants present a promising biomechanical behavior for dissipating the masticatory load in comparison with conventional screw-shaped implants.

The potential use of nanozymes as an antibacterial agents in oral infection, periodontitis, and peri-implantitis

Several studies suggest that oral pathogenic biofilms cause persistent oral infections. Among these is periodontitis, a prevalent condition brought on by plaque biofilm. It can even result in tooth loss. Furthermore, the accumulation of germs around a dental implant may lead to peri-implantitis, which damages the surrounding bone and gum tissue. Furthermore, bacterial biofilm contamination on the implant causes soft tissue irritation and adjacent bone resorption, severely compromising dental health. On decontaminated implant surfaces, however, re-osseointegration cannot be induced by standard biofilm removal techniques such as mechanical cleaning and antiseptic treatment. A family of nanoparticles known as nanozymes (NZs) comprise highly catalytically active multivalent metal components. The most often employed NZs with antibacterial activity are those that have peroxidase (POD) activity, among other types of NZs. Since NZs are less expensive, more easily produced, and more stable than natural enzymes, they hold great promise for use in various applications, including treating microbial infections. NZs have significantly contributed to studying implant success rates and periodontal health maintenance in periodontics and implantology. An extensive analysis of the research on various NZs and their applications in managing oral health conditions, including dental caries, dental pulp disorders, oral ulcers, peri-implantitis, and bacterial infections of the mouth. To combat bacteria, this review concentrates on NZs that imitate the activity of enzymes in implantology and periodontology. With a view to the future, there are several ways that NZs might be used to treat dental disorders antibacterially.

Periodontists and oral surgeons' peri-implantitis-related education, knowledge, attitudes, and professional behavior: A national survey

OBJECTIVES

Each year, approximately 5 million dental implants are placed in the United States and one out of three patients is likely to experience peri-implantitis (PI). The objectives were to compare the PI-related education, knowledge, attitudes, and professional behavior of periodontists and oral maxillofacial surgeons (OMS), and to explore relationships between these constructs of interest.

METHODS

A total of 389 periodontists and 161 OMS responded to a web-based survey. Descriptive and inferential statistical analyses (independent sample t-tests, chi-square tests, and correlational analyses) were conducted.

RESULTS

On average, periodontists reported a higher percentage of time spent in residency on implant surgery (21.02% vs. 7.27%; p < 0.001), better education about PI (5-point scale with 1 = not at all well: means: 2.86 vs. 2.59; p < 0.001), and better knowledge of risk factors (4.07 vs. 3.86; p < 0.001) than OMS. Periodontists argued that oral hygiene-related treatment (4.45 vs. 4.22; p = 0.001) and regeneration-focused treatments such as guided tissue regeneration (3.62 vs. 3.20; p < 0.001) contributed more to successfully treating PI and used these treatments more in their practices (4.86 vs. 4.56; p < 0.001/3.06 vs. 2.68; p < 0.001) than OMS. They also considered PI as a more serious problem than OMS (4.55 vs. 3.80; p < 0.001). The better the respondents' PI-related knowledge was, the more they considered PI as a serious problem (r = 0.19; p < 0.001). The more cases they treated per month, the more they considered PI as a serious problem (r = 0.19; p < 0.001).

CONCLUSIONS

The results of the present study highlight the lack of standardization in the specialty training of periodontists and OMS. Best practice guidelines for the diagnosis and treatment of PI are needed to optimize graduate education about this important topic.

Silver-deposited titanium as a prophylactic 'nano coat' for peri-implantitis

Dental implant failures caused by bacterial infections are a significant concern for dental implantologists. We modified the titanium surface by depositing silver (Ti-Ag) using direct current (DC) sputtering and confirmed the formation of a 'nano coat' by X-ray photoelectron spectroscopy (XPS), surface profilometry and energy dispersive spectroscopy (EDS). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed the deposition of a uniform nano Ag thin film. A gradual increase in thickness was observed, and the film thickness (530 nm) at 5 min deposition time (Ti-Ag5) resulted in a reduction of the water contact angle (WCA, 15%) and an increase in surface energy (SFE, 22%) in comparison to the uncoated Ti surface. Using inductively coupled plasma-atomic emission spectroscopy (ICP-AES), the slow, steady release of Ag from the coating was observed over 21 days. The Ti-Ag5 surface exhibited excellent antibacterial activity against Streptococcus oralis, Streptococcus sanguinis, Aggregatibacter actinomycetemcomitans, and Porphyromonas gingivalis, which belonged to the yellow, purple, and red complexes, representing specific periodontal pathogens. Furthermore, we observed excellent cytocompatibility of Ag-deposited Ti towards MG-63 osteoblasts with no inhibitory effect on their proliferative potential. Quantitation of alkaline phosphatase (ALP) activity, mineralization efficiency, and osteogenesis-related gene expression of MG-63 cells over 21 days was suggestive of rapid osseointegration. Overall, the 'nano coat' of Ag on Ti is indeed a prophylactic against peri-implantitis, ensuring increased implant success.

The biofilm removal effect and osteogenic potential on the titanium surface by electrolytic cleaning: An in vitro comparison of electrolytic parameters and five techniques

OBJECTIVES

To determine the optimal current and time of electrolytic cleaning (EC), compare its biofilm removal effect with generic treatments and evaluate the influence of EC to surface characteristics and osteogenic potential of SLA titanium (Ti) discs.

MATERIALS AND METHODS

The six-species biofilm-covered Ti discs were placed as cathodes in physiologic saline and subjected to various current and time treatments. The residual biofilms were evaluated to determine the optimal parameters. The contaminated Ti discs were randomized and treated by rotating Ti brush; ultrasonic-scaling with metal tips; ultrasonic-scaling with PEEK tips; air-polishing and EC. The residual biofilms were compared using a lipopolysaccharide kit (LPS), scanning electron microscope (SEM), confocal laser scanning microscopy and colony-forming unit counting. Non-contaminated Ti discs were treated and characterized. The bone marrow mesenchymal stem cells (BMSCs) were cultured on treated non-contaminated Ti discs. The adhesion, proliferation, alkaline phosphatase (ALP) activity and osteocalcin level of BMSCs were assessed.

RESULTS

The parameters at 0.6A5min were considered optimal. For LPS and SEM, EC promoted a significantly greater biofilm removal than the other groups. There were no changes in the Ti discs' colour, topography, roughness and chemical elements after EC, and the electrolysis-treated Ti discs obtained a super-hydrophilic surface. EC positively impacted the proliferation and ALP activity of BMSCs, surpassing the efficacy of alternative treatments.

CONCLUSIONS

EC achieves a near-complete eradication of contaminants on the SLA surface, causes no surface damage with improved hydrophilicity, and promotes the early osteogenic response of BMSCs, which makes it a promising treatment for peri-implantitis.

Enhanced osteogenic and antibacterial properties of titanium implant surface modified with Zn-incorporated nanowires: Preclinical in vitro and in vivo investigations

OBJECTIVE

This study aimed to synthesize zinc-incorporated nanowires structure modified titanium implant surface (Zn-NW-Ti) and explore its superior osteogenic and antibacterial properties in vitro and in vivo.

MATERIALS AND METHODS

Zn-NW-Ti was synthesized via displacement reactions between zinc sulfate solutions and the titanium (Ti) surface, which was pretreated by hydrofluoric acid etching and hyperthermal alkalinization. The physicochemical properties of the Zn-NW-Ti surface were examined. Moreover, the biological effects of Zn-NW-Ti on MC3T3-E1 cells and its antibacterial property against oral pathogenic bacteria (Staphylococcus aureus, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans) compared with sandblasted and acid-etched Ti (SLA-Ti) and nanowires modified Ti (NW-Ti) surface were assessed. Zn-NW-Ti and SLA-Ti modified implants were inserted into the anterior extraction socket of the rabbit mandible with or without exposure to the mixed bacterial solution (S. aureus, P. gingivalis, and A. actinomycetemcomitans) to investigate the osteointegration and antibacterial performance via radiographic and histomorphometric analysis.

RESULTS

The Zn-NW-Ti surface was successfully prepared. The resultant titanium surface appeared as a nanowires structure with hydrophilicity, from which zinc ions were released in an effective concentration range. The Zn-NW-Ti surface performed better in facilitating the adhesion, proliferation, and differentiation of MC3T3-E1 cells while inhibiting the colonization of bacteria compared with SLA-Ti and NW-Ti surface. The Zn-NW-Ti implant exhibited enhanced osseointegration in vivo, which was attributed to increased osteogenic activity and reduced bacterial-induced inflammation compared with the SLA-Ti implant.

CONCLUSIONS

The Zn-incorporated nanowires structure modified titanium implant surface exhibited improvements in osteogenic and antibacterial properties, which optimized osteointegration in comparison with SLA titanium implant surface.

Prevalence of Peri-Implant Mucositis, Peri-Implantitis and Associated Risk Indicators of Implants with and without Laser-Microgrooved Collar Surface: A Long-Term (≥20 Years) Retrospective Study

The aim of the current study was to retrospectively investigate the prevalence of peri-implant mucositis (PIM) and peri-implantitis (P) in a long-term follow-up (≥20 years) of implants with the same body design and body surface but different collar surfaces with laser-microtextured grooves (LMGSs) vs. no laser-microtextured grooves (no-LMGSs) in private practice patients. Furthermore, several patient-related, implant-related, site-, surgical-, and prosthesis-related potential disease risk factors were analyzed. A chart review of patients receiving at least one pair of implants (one with an LMGS and the other without LMGS) in the period 1993-2002 was used. Chi-square analysis was used to determine if a statistically significant difference between the investigated variables and PIM/P was present. Possible risk factors were statistically evaluated by a binary logistic regression analysis. A total of 362 patients with 901 implant-supported restorations (438 with LMGS and 463 no-LMGS) were included in the study. The cumulative survival rates of implants at 5, 10, 15, and 20 years were 98.1%, 97.4%, 95.4%, and 89.8%, respectively, for the LMGS group, and 93.2%, 91.6%, 89.5%, and 78.3% for the no-LMGS group. The difference was statistically significant at all timepoints (p < 0.05). In total, at the end of the follow-up period, 45.7% of patients and 39.8% of implants presented PIM, and 15.6% of patients and 14% of implants presented P. A total of 164 LMGS implants (37.4%) and 195 no-LMGS implants (42.1%) presented peri-implant mucositis, while 28 (6.3%) of LMGS implants and 98 (21.1%) no-LMGS implants demonstrated peri-implantitis. Differences between LMGS implants and no-LMGS implants were statistically significant (p < 0.05). The binary logistic regression identified collar surface, cigarette smoking, histories of treated periodontitis, and lack of peri-implant maintenance as risk factors for P. After at least 20 years of function in patients followed privately, LMGS implants compared to no-LMGS implants presented a statistically and significantly lower incidence of P. Implant collar surface, cigarette smoking, previously treated periodontitis, and lack of peri-implant maintenance are factors with significant association to P.

The Efficacy of Ten Different Adjunctive Measures in Patients with Nonsurgically Treated Peri-Implant Disease: A Network Meta-Analysis of Randomized Controlled Trials

Objective: This study aimed to evaluate the impact of 10 adjunctive measures on non-surgical therapy outcomes for peri-implant disease. Methods: We formulated the study question and keywords following the Population, Intervention, Comparator, Outcome framework. Randomized controlled trials were identified through searches in PubMed, Embase, the Cochrane Library, and the Web of Science. Two researchers assessed the quality of included literature according to the Cochrane Risk of Bias Assessment Tool. Data analysis and ranking were performed using Stata 15.0 software. Results: This study, involving 51 pieces of literature and 2660 samples, conducted a network meta-analysis (NMA), which revealed that photodynamic therapy (PDT) significantly reduced probing pocket depth values in patients with peri-implant mucositis (SUCRA = 96.3%) and peri-implantitis (SUCRA = 96.7%). In addition, it showed an improvement in bleeding on probing (BOP) values for peri-implantitis (SUCRA = 91.6%). Furthermore, diode lasers improved BOP values for peri-implant mucositis (SUCRA = 76.5%). Conclusions: According to the NMA results and the surface under the cumulative ranking curve (SUCRA), PDT and diode laser outperform other adjuncts in peri-implant disease.

Predictive factors for the treatment success of peri-implantitis: a protocol for a prospective cohort study

INTRODUCTION

Peri-implantitis, a common biological complication of dental implant, has attracted considerable attention due to its increasing prevalence and limited treatment efficacy. Previous studies have reported several risk factors associated with the onset of peri-implantitis (eg, history of periodontitis, poor plaque control and smoking). However, inadequate data are available on the association between these risk factors and successful outcome after peri-implantitis therapy. This prospective cohort study aims to identify the local and systemic predictive factors for the treatment success of peri-implantitis.

METHODS AND ANALYSIS

A single-centre cohort study will be conducted by recruiting 275 patients diagnosed with peri-implantitis. Sociodemographic variables, healthy lifestyles and systemic disorders will be obtained using questionnaires. In addition, clinical and radiographic examinations will be conducted at baseline and follow-up visits. Treatment success is defined as no bleeding on probing on more than one point, no suppuration, no further marginal bone loss (≥0.5 mm) and probing pocket depth ≤5 mm at the 12-month follow-up interval. After adjustment for age, sex and socioeconomic status, potential prognostic factors related to treatment success will be identified using multivariable logistic regression models.

ETHICS AND DISSEMINATION

This cohort study in its current version (2.0, 15 July 2022) is in accordance with the Declaration of Helsinki and was approved by the Ethics Committee of Stomatological Hospital, Southern Medical University (EC-CT-(2022)34). The publication will be on behalf of the study site.

TRIAL REGISTRATION NUMBER

ChiCTR2200066262.

Contemporary issues in the management of dental trauma

Contemporary diagnosis and management of traumatic dental injuries requires a multifaceted understanding of the pathological and psychological impact over a patient's lifetime. The legacy of dental trauma injuries can have repercussions for the dentition and supporting tissues, requiring complicated multidisciplinary clinical input. Foresight is required to ensure optimal aesthetic and functional outcomes. Mitigating risks and maximising benefits in patients presenting with polytrauma can be challenging, but if optimally managed at the acute presentation, the long-term burden to the patient and the clinician is reduced. This paper aims to discuss the contemporary clinical dilemmas, challenges and controversies related to the management of dental trauma.

A Dual-Antioxidative Coating on Transmucosal Component of Implant to Repair Connective Tissue Barrier for Treatment of Peri-Implantitis

Since the microgap between implant and surrounding connective tissue creates the pass for pathogen invasion, sustained pathological stimuli can accelerate macrophage-mediated inflammation, therefore affecting peri-implant tissue regeneration and aggravate peri-implantitis. As the transmucosal component of implant, the abutment therefore needs to be biofunctionalized to repair the gingival barrier. Here, a mussel-bioinspired implant abutment coating containing tannic acid (TA), cerium and minocycline (TA-Ce-Mino) is reported. TA provides pyrogallol and catechol groups to promote cell adherence. Besides, Ce3+ /Ce4+  conversion exhibits enzyme-mimetic activity to remove reactive oxygen species while generating O2 , therefore promoting anti-inflammatory M2 macrophage polarization to help create a regenerative environment. Minocycline is involved on the TA surface to create local drug storage for responsive antibiosis. Moreover, the underlying therapeutic mechanism is revealed whereby the coating exhibits exogenous antioxidation from the inherent properties of Ce and TA and endogenous antioxidation through mitochondrial homeostasis maintenance and antioxidases promotion. In addition, it stimulates integrin to activate PI3K/Akt and RhoA/ROCK pathways to enhance VEGF-mediated angiogenesis and tissue regeneration. Combining the antibiosis and multidimensional orchestration, TA-Ce-Mino repairs soft tissue barriers and effector cell differentiation, thereby isolating the immune microenvironment from pathogen invasion. Consequently, this study provides critical insight into the design and biological mechanism of abutment surface modification to prevent peri-implantitis.

Application of Immediate Implant Placement Techniques in Peri-implantitis Modeling

OBJECTIVES

To explore the use of immediate implant placement technique in peri-implantitis modeling, shorten the modeling period, and obtain similar effects.

MATERIALS AND METHODS

Eighty rats were divided into 4 groups: immediate placement (IP), delayed placement (DP), IP-ligation (IP-L) and DP-ligation (DP-L). In the DP and DP-L groups, implants were placed 4 weeks after tooth extraction. In the IP and IP-L groups, implants were placed immediately. Four weeks later, the implants were ligated to induce peri-implantitis in the DP-L and IP-L groups.

RESULTS

Nine implants were lost (3 in the IP-L and 2 each in the IP, DP, and DP-L group). The bone level decreased after ligation, and the buccal and lingual bone levels were lower in IP-L versus DP-L. The implant pullout strength was decreased after ligation. Micro-CT showed bone parameters were decreased after ligation, and the percent bone volume was higher in IP versus DP. Histology showed that the percent of CD4 + cells and IL-17 + cells was increased after ligation and higher in IP-L versus DP-L.

CONCLUSIONS

We successfully introduced immediate implant placement into the modeling of peri-implantitis and observed similar bone resorption and more soft tissue inflammation in a shorter time.

Long-term evaluation of peri-implant keratinized mucosa stability after free epithelialized graft and keratinized mucosa shifting procedures: A retrospective study up to 13 years

OBJECTIVES

This study aimed to assess the risk of less than 2 mm keratinized mucosa (KM) width occurrence after free epithelialized graft (FEG) and keratinized mucosa shifting (KMS) procedures using survival analysis. In addition, KM dimensional changes were evaluated.

MATERIALS AND METHODS

This study included 76 implants in 36 patients with insufficient KM (<2 mm). The implants underwent either FEG or KMS procedures. The mid-buccal KM width was measured from surgery to the end of a one 13-year follow-up period.

RESULTS

Mean follow-up durations were 9.2 ± 3.9 years for FEG and 6.3 ± 4.2 years for KMS. Two implants in FEG and nine implants in KMS exhibited a KM width of less than 2 mm during follow-up. The hazard ratios for KMS compared to FEG were 6.48 (crude) and 6.54 (adjusted), both statistically significant (p < .05). The incidence rate of KMS (4.06%) was higher than that of FEG (0.63%), with an average incidence time of 3.38 years for KMS and 8.82 years for FEG post-surgery. FEG showed a significant shrinkage within 6 months (33% ± 22%), whereas KMS demonstrated a gradual decrease over 13 years (34% ± 25%). FEG exhibited significantly greater width change than KMS during a 5-year follow-up (p < .05).

CONCLUSIONS

FEG and KMS enhanced PIKM but exhibited different long-term reduction patterns. FEG demonstrated rapid shrinkage, while KMS displayed gradual and continuous reduction. Moreover, KMS presented a higher risk and incidence of KM width less than 2 mm compared to FEG.

Overview of strategies to improve the antibacterial property of dental implants

The increasing number of peri-implant diseases and the unsatisfactory results of conventional treatment are causing great concern to patients and medical staff. The effective removal of plaque which is one of the key causes of peri-implant disease from the surface of implants has become one of the main problems to be solved urgently in the field of peri-implant disease prevention and treatment. In recent years, with the advancement of materials science and pharmacology, a lot of research has been conducted to enhance the implant antimicrobial properties, including the addition of antimicrobial coatings on the implant surface, the adjustment of implant surface topography, and the development of new implant materials, and significant progress has been made in various aspects. Antimicrobial materials have shown promising applications in the prevention of peri-implant diseases, but meanwhile, there are some shortcomings, which leads to the lack of clinical widespread use of antimicrobial materials. This paper summarizes the research on antimicrobial materials applied to implants in recent years and presents an outlook on the future development.

The integration of peri-implant soft tissues around zirconia abutments: Challenges and strategies

Stable soft tissue integration around the implant abutment attenuates pathogen penetration, protects underlying bone tissue, prevents peri-implantitis and is essential in maintaining long-term implant stability. The desire for "metal free" and "aesthetic restoration" has favored zirconia over titanium abutments, especially for implant restorations in the anterior region and for patients with thin gingival biotype. Soft tissue attachment to the zirconia abutment surface remains a challenge. A comprehensive review of advances in zirconia surface treatment (micro-design) and structural design (macro-design) affecting soft tissue attachment is presented and strategies and research directions are discussed. Soft tissue models for abutment research are described. Guidelines for development of zirconia abutment surfaces that promote soft tissue integration and evidence-based references to inform clinical choice of abutment structure and postoperative maintenance are presented.

The Potential Value of Probiotics after Dental Implant Placement

Dental implantation is currently the optimal solution for tooth loss. However, the health and stability of dental implants have emerged as global public health concerns. Dental implant placement, healing of the surgical site, osseointegration, stability of bone tissues, and prevention of peri-implant diseases are challenges faced in achieving the long-term health and stability of implants. These have been ongoing concerns in the field of oral implantation. Probiotics, as beneficial microorganisms, play a significant role in the body by inhibiting pathogens, promoting bone tissue homeostasis, and facilitating tissue regeneration, modulating immune-inflammatory levels. This review explores the potential of probiotics in addressing post-implantation challenges. We summarize the existing research regarding the importance of probiotics in managing dental implant health and advocate for further research into their potential applications.

Adjunctive benefit of probiotic supplementation along with nonsurgical therapy for peri-implant diseases - A systematic review and meta-analysis

Peri-implant diseases are prevalent conditions, but a predictable management strategy is still lacking. The objective of the present article was to evaluate the adjunctive benefits of probiotics with nonsurgical therapy in the management of peri-implant diseases. The review protocol was registered in PROSPERO and prepared according to PRISMA guidelines. Randomized controlled clinical trials in patients diagnosed with the peri-implant disease where probiotic was used as an adjunct to nonsurgical therapy were included in the study. The risk difference of percentage reduction in bleeding on probing, plaque accumulation, and mean difference in probing pocket depth reductions at implant level were estimated using a random effect model due to high heterogeneity among studies. Four studies fulfilled the criteria for selection. Two of them presented data on both peri-implantitis and peri-implant mucositis and they were considered separate studies during meta-analysis. Significant reduction in percentage of bleeding on probing was noticed at 1 and 3 months (-0.28 [-0.48, -0.09], P = 0.004 and - 0.19 [-0.35, -0.02], P = 0.03, respectively), but the reduction was not statistically significant at 6 months. Similar results were also observed for plaque accumulation. No statistically significant reduction in probing pocket depth was observed in the probiotic group during any of the re-evaluations.

Conclusion

Adjunctive therapy of probiotics may improve the efficacy of nonsurgical therapy of peri-implant diseases for up to 3 months. However, moderate certainty was observed for a reduction in bleeding on probing after 1-month re-evaluation alone.

Clinical and Radiological Characterization of the Long-Term Association between Unaffected/Minimally Affected Implants and History of Severe Periodontitis: A Retrospective Study

OBJECTIVES

The objectives of this research were to compare, retrospectively, the clinical and radiographic modifications of periodontal parameters and peri-implant conditions and to analyze the relationship between the changes in periodontal parameters and peri-implant conditions over a mean follow-up period of 7.6 years in a treated population with progressive/uncontrolled periodontitis and at least one unaffected/minimally affected implant.

MATERIALS AND METHODS

Nineteen partially edentulous patients having 77 implants inserted, with a mean age of 54.84 ± 7.60 years, were matched for age, gender, compliance, smoking status, general health, and implant characteristics. Periodontal parameters were evaluated in the remaining teeth. Means per teeth and implants were used when making comparisons.

RESULTS

Statistically significant differences were observed between baseline and final examination in teeth for tPPD, tCAL and MBL. Furthermore, at 7.6 years, statistically significant differences existed between implants and teeth with regard to iCAL and tCAL (p = 0.03). Multiple regression analyses were performed and revealed a significant association regarding iPPD and CBL with smoking and periodontal diagnosis. In addition, FMBS was significantly associated with CBL. Unaffected/minimally affected implants were found more frequently in the posterior mandible, with longer lengths (>10 mm) and small diameters (<4 mm), including in screwed multi-unit bridges.

CONCLUSIONS

The study results appear to reflect minimally affected mean crestal bone-level loss around implants in comparison to the marginal bone-level loss around teeth when exposed to uncontrolled severe periodontal disease over a mean period of observation of 7.6 years, while the unaffected/minimally affected implants seemed to benefit from a combination of clinical factors, including posterior mandibular position, smaller diameters, and screwed multi-unit restorations.

Antimicrobial Efficiency of Pistacia lentiscus L. Derivates against Oral Biofilm-Associated Diseases-A Narrative Review

Pistacia lentiscus L. (PlL) has been used for centuries in traditional medicine. The richness in antimicrobial biomolecules of Pll derivates can represent an alternative to chemically formulated agents used against oral infections. This review summarizes the knowledge on the antimicrobial activity of PlL essential oil (EO), extracts, and mastic resin against microorganisms being of relevance in oral biofilm-associated diseases. Results demonstrated that the potential of PlL polyphenol extracts has led to increasing scientific interest. In fact, the extracts are a significantly more effective agent than the other PlL derivates. The positive findings regarding the inhibition of periodontal pathogens and C. albicans, together with the antioxidant activity and the reduction of the inflammatory responses, suggest the use of the extracts in the prevention and/or reversal of intraoral dysbiosis. Toothpaste, mouthwashes, and local delivery devices could be effective in the clinical management of these oral diseases.

The Influence of Fixed Dental Prostheses on the Expression of Inflammatory Markers and Periodontal Status-Narrative Review

A dental prosthesis will only be successful if the restoration lasts for a long period and does not cause any illness. The presence of permanent prosthetic restorations has been linked to an increased risk of periodontal infections, according to a large body of research that has been gathered. When chronic inflammation is brought on by fixed prosthetic constructions, both cellular and noncellular immunity are activated as adaptive immune mechanisms. It has previously been stated that both clinically adequate and inadequate restorations might cause gingival inflammation. Areas surrounding the abutment teeth presented periodontal pockets, attachment loss, congestion, bleeding on probing, and gingival hyperplasia after fixed restorations were removed. The depth of pockets, bleeding on probing, and bone loss are all closely correlated with disease's severity and IL-1β concentration in gingival crevicular fluid; IL-1β shows higher values in disease sites than in healthy ones. hs-CRP and TNF-α blood levels showed a considerable reduction one day after fixed restorations were applied, in comparison with the pre-treatment values. Collaboration between prosthodontists and periodontists is essential for a good treatment outcome since it will increase the restoration's lifespan, enhance periodontal health, and improve the quality of life for dental patients.

Effects of Hypochlorous Acid and Hydrogen Peroxide Treatment on Bacterial Disinfection Treatments in Implantoplasty Procedures

One of the main problems in oral implantology today is peri-implantitis, which affects almost 20% of dental implants placed in patients. One of the most commonly used techniques to eliminate bacterial biofilm is the implantoplasty, that consists of the mechanical modification of the implant surface topography followed by treatments with chemical reagents for decontamination. In this study, the main aim is to evaluate the use of two different chemical treatments based on hypochlorous acid (HClO) and hydrogen peroxide (H₂O₂). For this purpose, 75 titanium grade 3 discs were treated with implantoplasty according to established protocols. Twenty-five discs were used as controls, 25 were treated with concentrated HClO and 25 were treated with concentrated HClO followed by treatment with 6% H₂O₂. The roughness of the discs was determined using the interferometric process. Cytotoxicity with SaOs-2 osteoblastic cells was quantified at 24 and 72 h, whereas bacteria proliferation using S. gordonii and S. oralis bacteria was quantified at 5 s and 1 min of treatment. The results showed an increase in the roughness values, the control discs had an Ra of 0.33 μm and those treated with HClO and H₂O₂ reached 0.68 μm. Cytotoxicity was present at 72 h, together with a significant proliferation of bacteria. These biological and microbiological results can be attributed to the roughness produced by the chemical agents that triggered bacterial adsorption while inhibiting osteoblast adhesion. The results indicate that even if this treatment can decontaminate the titanium surface after implantation, the produced topography will generate an environment that will not favor long-term performance.

Peri-implantitis after 40 years: Evidence, mechanisms, and implications: A mapping review

STATEMENT OF PROBLEM

The high prevalence of peri-implantitis (PI) continues to plague patients and the disease is resistant to present treatment regimens. An analysis of the available research is lacking.

PURPOSE

Given the abundance and diversity of research on the topic of PI, the purpose of this mapping review was to synthesize the literature on the prevention of PI, the histopathology of the disease, the state of present therapeutics, and any emerging treatments.

MATERIAL AND METHODS

An extensive literature search was undertaken by using the electronic databases of PubMed, Web of Science, and Science Direct. The keyword strings were peri-implantitis, dental implant, risk assessment, histopathology, prosthesis design, and treatment. The filters applied were time interval from 2000 to 2002; language, English.

RESULTS

A total of 3635 articles were taken from PubMed, 3686 articles from Web of Science, and 2450 articles from Science Direct. After applying the inclusion and exclusion criteria to the titles and abstracts of selected investigations, 214 studies were retrieved.

CONCLUSIONS

The evidence reflects a concerning incidence of PI, without a predictable treatment protocol. An in-depth patient risk assessment considering risk modification, emphasis on surgical and restorative expertise, and strict recall and maintenance is essential to minimize PI.

Comparing the Long-Term Success Rates of Tooth Preservation and Dental Implants: A Critical Review

Implant therapy is considered a predictable, safe, and reliable rehabilitation method for edentulous patients in most clinical scenarios. Thus, there is a growing trend in the indications for implants, which seems attributable not only to their clinical success but also to arguments such as a more “simplified approach” based on convenience or the belief that dental implants are as good as natural teeth. Therefore, the objective of this critical literature review of observational studies was to discuss the evidence concerning the long-term survival rates and treatment outcomes, comparing endodontically or periodontally treated teeth with dental implants. Altogether, the evidence suggests that the decision between keeping a tooth or replacing it with an implant should carefully consider the condition of the tooth (e.g., amount of remaining tooth and degree of attachment loss and mobility), systemic disorders, and patient preference. Although observational studies revealed high success rates and long-term survival of dental implants, failures and complications are common. For this reason, attempts should be made to first save maintainable teeth over the long-term, instead of immediately replacing teeth with dental implants.

Primordial and primary prevention of peri-implant diseases: A systematic review and meta-analysis

AIM

This systematic review and meta-analysis aims to assess the efficacy of risk factor control to prevent the occurrence of peri-implant diseases (PIDs) in adult patients awaiting dental implant rehabilitation (primordial prevention) or in patients with dental implants surrounded by healthy peri-implant tissues (primary prevention).

MATERIALS AND METHODS

A literature search was performed without any time limit on different databases up to August 2022. Interventional and observational studies with at least 6 months of follow-up were considered. The occurrence of peri-implant mucositis and/or peri-implantitis was the primary outcome. Pooled data analyses were performed using random effect models according to the type of risk factor and outcome.

RESULTS

Overall, 48 studies were selected. None assessed the efficacy of primordial preventive interventions for PIDs. Indirect evidence on the primary prevention of PID indicated that diabetic patients with dental implants and good glycaemic control have a significantly lower risk of peri-implantitis (odds ratio [OR] = 0.16; 95% confidence interval [CI]: 0.03-0.96; I² : 0%), and lower marginal bone level (MBL) changes (OR = -0.36 mm; 95% CI: -0.65 to -0.07; I² : 95%) compared to diabetic patients with poor glycaemic control. Patients attending supportive periodontal/peri-implant care (SPC) regularly have a lower risk of overall PIDs (OR = 0.42; 95% CI: 0.24-0.75; I² : 57%) and peri-implantitis compared to irregular attendees. The risk of dental implant failure (OR = 3.76; 95% CI: 1.50-9.45; I² : 0%) appears to be greater under irregular or no SPC than regular SPC. Implants sites with augmented peri-implant keratinized mucosa (PIKM) show lower peri-implant inflammation (SMD = -1.18; 95% CI: -1.85 to -0.51; I² : 69%) and lower MBL changes (MD = -0.25; 95% CI: -0.45 to -0.05; I² : 62%) compared to dental implants with PIKM deficiency. Studies on smoking cessation and oral hygiene behaviors were inconclusive.

CONCLUSIONS

Within the limitations of available evidence, the present findings indicate that in patients with diabetes, glycaemic control should be promoted to avoid peri-implantitis development. The primary prevention of peri-implantitis should involve regular SPC. PIKM augmentation procedures, where a PIKM deficiency exists, may favour the control of peri-implant inflammation and the stability of MBL. Further studies are needed to assess the impact of smoking cessation and oral hygiene behaviours, as well as the implementation of standardized primordial and primary prevention protocols for PIDs.

Risk indicators of long-term outcome of implant therapy in patients with a history of severe periodontitis or no history of periodontitis: A retrospective cohort study

OBJECTIVE

The aim of this retrospective cohort study was to assess factors associated with peri-implant disease in partially edentulous patients with a history of severe periodontitis or no history of periodontitis.

METHODS

Partially edentulous patients with a history of severe periodontitis/without history of periodontitis who received implant surgery within the past 6 to 8 years were recalled. Clinical and radiographic examinations were recorded. Periodontal probing depth, marginal bone loss (MBL) and peri-implantitis were considered as the primary outcome and peri-implant bleeding on probing (BOP) was considered as the secondary outcome. The following criteria were considered as the predictors, as well: history of severe periodontitis, gender, age, smoking, brushing frequency, recall interval, full-mouth plaque score, full-mouth bleeding score, splinted prosthesis, open/tight interproximal contact, width of keratinized mucosa, mucosal thickness, implants placed in the grafted bone and implant type. Univariate and multivariate regression analyses were utilized.

RESULTS

A total of 88 patients (186 implants) fulfilled the study. Forty-seven patients (108 implants) had a history of severe periodontitis and 41 patients (78 implants) had no history of periodontitis. There was a higher chance of peri-implantitis in patients with a history of severe periodontitis (OR = 11.13; p = 0.045), implants with lack of peri-implant KM (<2 mm) and implants placed in the grafted bone (OR = 14.94, p < 0.001; OR = 4.93, p = 0.047). The risk of peri-implant MBL ≥3 mm was higher in patients with greater FMBS (OR = 1.20; p < 0.001). The chance of peri-implant BOP was independently higher in patients who brushed their teeth at most once per day (OR = 3.20; p = 0.04), higher FMBS (OR = 1.16; p < 0.001) and irregular recall visits (OR = 15.34; p = 0.001).

CONCLUSIONS

Partially edentulous patients with the history of severe periodontitis, lack of peri-implant KM and implants placed in bone-grafted sites expressed higher probability of peri-implantitis. In addition, inadequate frequency of brushing (at most once daily) and irregular recall visits were associated with greater chance of peri-implant BOP.

Immunomodulatory IL-23 receptor antagonist peptide nanocoatings for implant soft tissue healing

OBJECTIVE

Peri-implantitis, caused by an inflammatory response to pathogens, is the leading cause of dental implant failure. Poor soft tissue healing surrounding implants - caused by inadequate surface properties - leads to infection, inflammation, and dysregulated keratinocyte and macrophage function. One activated inflammatory response, active around peri-implantitis compared to healthy sites, is the IL-23/IL-17A cytokine axis. Implant surfaces can be synthesized with peptide nanocoatings to present immunomodulatory motifs to target peri-implant keratinocytes to control macrophage polarization and regulate inflammatory axises toward enhancing soft tissue healing.

METHODS

We synthesized an IL-23 receptor (IL-23R) noncompetitive antagonist peptide nanocoating using silanization and evaluated keratinocyte secretome changes and macrophage polarization (M1-like "pro-inflammatory" vs. M2-like "pro-regenerative").

RESULTS

IL-23R antagonist peptide nanocoatings were successfully synthesized on titanium, to model dental implant surfaces, and compared to nonfunctional nanocoatings and non-coated titanium. IL-23R antagonist nanocoatings significantly decreased keratinocyte IL-23, and downstream IL-17A, expression compared to controls. This peptide noncompetitive antagonistic function was demonstrated under lipopolysaccharide stimulation. Large scale changes in keratinocyte secretome content, toward a pro-regenerative milieu, were observed from keratinocytes cultured on the IL-23R antagonist nanocoatings compared to controls. Conditioned medium collected from keratinocytes cultured on the IL-23R antagonist nanocoatings polarized macrophages toward a M2-like phenotype, based on increased CD163 and CD206 expression and reduced iNOS expression, compared to controls.

SIGNIFICANCE

Our results support development of IL-23R noncompetitive antagonist nanocoatings to reduce the pro-inflammatory IL-23/17A pathway and augment macrophage polarization toward a pro-regenerative phenotype. Immunomodulatory implant surface engineering may promote soft tissue healing and thereby reduce rates of peri-implantitis.

Soft-Tissue Augmentation around Dental Implants with a Connective Tissue Graft (CTG) and Xenogeneic Collagen Matrix (CMX)-5-Year Follow-Up

Proper horizontal and vertical thickness of the gingival connective tissue has been proven to be one of the success criteria in dental implant and reconstructive surgery. When thin tissue is found, gingiva augmentation methods can be used to increase the quality and volume of the tissue. Many methods have been described, among them pedicle soft-tissue flaps or autogenic tissue grafts. As an alternative to patients' own tissue, xenogenic materials can be used for grafting. The fundamental issue is to choose a material that will ensure the maximum therapeutic effect, while also minimizing the negative influence on the patient's health. The aim of this study was to compare gingival augmentation procedures using a palatal connective tissue graft (CTG) and an xenogenic soft-tissue substitute, Geistlich Mucograft (xenogeneic collagen matrix; CMX), and assess whether the timing of the graft surgery influences the clinical outcomes. The original study was a randomized control trial with a total of 75 implants placed. The patients received the soft-tissue thickening 3 months before the implant placement or 3 months after the implant placement (depending on the group). A connective tissue graft (CTG) or Geistlich Mucograft were used (depending on the group). For both the CTG and Geistlich Mucograft, better clinical outcomes were observed for maintaining the alveolar bone level and the thickness of the attached gingiva compared to the control group with no gingival augmentation. The Geistlich Mucograft showed good clinical performance in comparison to the control. Soft-tissue augmentation with the CTG before the implant placement was found to be most efficient method in terms of a stable increase of the tissue thickness since, throughout the entire observation period, the greatest increase of 1.035 mm (SD = 0.73 mm) in thickness was observed. Statistically important differences in the tissue thickness baseline compared after 5 years were observed for groups G1 vs. G2b (no augmentation vs. CTG before), G1 vs. G3b (no augmentation vs. CTG after) and for groups G2b vs. G3a (CTG before vs. CMX after).

Graphene and its derivatives: "one stone, three birds" strategy for orthopedic implant-associated infections

Orthopedic implants provide an avascular surface for microbial attachment and biofilm formation, impeding the entry of immune cells and the diffusion of antibiotics. The above is an important cause of dental and orthopedic implant-associated infection (IAI). For the prevention and treatment of IAI, the drawbacks of antibiotic resistance and surgical treatment are increasingly apparent. Due to their outstanding biological properties such as biocompatibility, immunomodulatory effects, and antibacterial properties, graphene-based nanomaterials (GBNs) have been applied to bone tissue engineering to deal with IAI, and in particular have great potential application in drug/gene carriers, multi-functional platforms, and coating forms. Here we review the latest research progress and achievements in GBNs for the prevention and treatment of IAI, mainly including their biomedical applications for antibacterial and immunomodulation effects, and for inducing osteogenesis. Furthermore, the biosafety of graphene family materials in bone tissue regeneration and the feasibility of clinical application are critically analyzed and discussed.

Nanostructured Calcium-Incorporated Surface Compared to Machined and SLA Dental Implants-A Split-Mouth Randomized Case/Double-Control Histological Human Study

Background: Implant surface topography is a key element in achieving osseointegration. Nanostructured surfaces have shown promising results in accelerating and improving bone healing around dental implants. The main objective of the present clinical and histological study is to compare, at 4 and 6 weeks, (w) bone-to-implant contact in implants having either machined surface (MAC), sandblasted, large grit, acid-etched implant surface (SLA) medium roughness surface or a nanostructured calcium-incorporated surface (XPEED®). Methods: 35 mini-implants of 3.5 × 8.5 mm with three different surface treatments (XPEED® (n = 16)—SLA (n = 13)—MAC (n = 6), were placed in the posterior maxilla of 11 patients (6 females and 5 males) then, retrieved at either 4 or 6w in a randomized split-mouth study design. Results: The BIC rates measured at 4w and 6w respectively, were: 16.8% (±5.0) and 29.0% (±3.1) for MAC surface; 18.5% (±2.3) and 33.7% (±3.3) for SLA surface; 22.4% (±1.3) and 38.6% (±3.2) for XPEED® surface. In all types of investigated surfaces, the time factor appeared to significantly increase the bone to implant contact (BIC) rate (p < 0.05). XPEED® surface showed significantly higher BIC values when compared to both SLA and MAC values at 4w (p < 0.05). Also, at 6w, both roughened surfaces (SLA and XPEED®) showed significantly higher values (p < 0.05) than turned surface (MAC). Conclusions: Nanostructured Calcium titanate coating is able to enhance bone deposition around implants at early healing stages.

The Effectiveness of a Bioactive Healing Abutment as a Local Drug Delivery System to Impact Peri-Implant Mucositis: A Prospective Case Series Study

Modern dental therapy makes use of prosthetic implant reconstructions, which are supported or retained on dental implants. The most frequent, long-term complications associated with these prosthetic implants include mucositis and peri-implantitis. Since mucositis is the initial inflammation of tissues supporting the dental implant, the management of this condition is thus crucial. The aim of the present study was to assess the effects of the placement of bioactive healing abutment for 48 h, in patients diagnosed with peri-implant mucositis. Moreover, the quantitative and qualitative shift in the bacterial profile of the biofilm present in the peri-implant pockets, was assessed by means of RT-PCR genotyping. Each patient was examined using a commercially available PET test protocol: the first sample was taken upon diagnosis (after which the bioactive healing abutment, with clindamycin at a dose of 30 mg, was used for 48 h and replaced with the prosthetic superstructure used so far by a patient); the second sample was taken two weeks after removal of the bioactive healing abutment. The effects of the intervention were clinically assessed using the PET test after the two weeks. A significant reduction in mucositis was observed following treatment, as measured by periodontal indices: modified Sulcus Bleeding Index—mBI (p < 0.001), modified Plaque Index—PLI (r = 0.69, Z= −4.43; p < 0.001) and probing depth—PD (Z = −4.61; p < 0.001). Significant differences in the occurrence of periopathogenic bacteria were also observed: Aggregatibacter actinomycetemcomitans (p < 0.014; Z = −2.45; r = 0.38), Treponema denticola (p < 0.005; Z = −2.83; r = 0.44), Tannerella forsythia (p < 0.001; Z = −4.47; r = 0.69) and Porphyromonas gingivalis (p < 0.132; Z = −1.51).

The Bio-Aging of Biofilms on Behalf of Various Oral Status on Different Titanium Implant Materials

The properties of titanium implants are affected by bio-aging due to long-term exposure to the oral microenvironment. This study aimed to investigate probable changes in titanium plates after different biofilm bio-aging processes, representing various oral status. Titanium plates with different surface treatments were used, including polish, sandblasted with large grit and acid etched (SLA), microarc oxidation (MAO), and hydroxyapatite coating (HA). We established dual-species biofilms of Staphylococcus aureus (S. aureus)-Candida albicans (C. albicans) and saliva biofilms from the healthy and patients with stage III-IV periodontitis, respectively. After bio-aging with these biofilms for 30 days, the surface morphology, chemical composition, and water contact angles were measured. The adhesion of human gingival epithelial cells, human gingival fibroblasts, and three-species biofilms (Streptococcus sanguis, Porphyromonas gingivalis, and Fusobacterium nucleatum) were evaluated. The polished specimens showed no significant changes after bio-aging with these biofilms. The MAO- and SLA-treated samples showed mild corrosion after bio-aging with the salivary biofilms. The HA-coated specimens were the most vulnerable. Salivary biofilms, especially saliva from patients with periodontitis, exhibited a more distinct erosion on the HA-coating than the S. aureus-C. albicans dual-biofilms. The coating became thinner and even fell from the substrate. The surface became more hydrophilic and more prone to the adhesion of bacteria. The S. aureus-C. albicans dual-biofilms had a comparatively mild corrosion effect on these samples. The HA-coated samples showed more severe erosion after bio-aging with the salivary biofilms from patients with periodontitis compared to those of the healthy, which emphasized the importance of oral hygiene and periodontal health to implants in the long run.

Association between Osteoprotegerin rs2073618 polymorphism and peri-implantitis susceptibility: a meta-analysis

OBJECTIVES

Peri-implantitis was an inflammatory progress on the tissue around the implant. The Osteoprotegerin G1181C (rs2073618) polymorphism was reported to be related to the increased risk of the peri-implantitis, whereas another found no relationship. The present study was conducted to research the relationship between Osteoprotegerin rs2073618 polymorphism and peri-implantitis susceptibility.

MATERIALS AND METHODS

The meta-analysis was performed according to the Preferred Reporting Items for Systematic reviews. Electronic databases including PubMed, Web of science, Springer Link and Embase (updated to April 15, 2022) were retrieved. The cohort study, case-control study or cross-sectional study focusing on the Osteoprotegerin rs2073618 polymorphism and peri-implantitis were retrieved. The data included basic information of each study and the genotype and allele frequencies of the cases and controls.

RESULTS

Three studies were finally included, including 160 cases and 271 controls. Allelic model, homozygote model, recessive model, dominant model, and heterozygous model were established to assess the relationship between OPG rs2073618 polymorphism and peri-implantitis susceptibility. The Osteoprotegerin rs2073618 polymorphism was significantly associated with peri-implantitis in Recessive model and Homozygote model.

CONCLUSION

OPG rs2073618 polymorphism in Recessive model and Homozygote model was highly likely related to the risk of peri-implantitis. PROSPERO registration number: CRD42022320812.

Junctional epithelium and hemidesmosomes: Tape and rivets for solving the "percutaneous device dilemma" in dental and other permanent implants

The percutaneous device dilemma describes etiological factors, centered around the disrupted epithelial tissue surrounding non-remodelable devices, that contribute to rampant percutaneous device infection. Natural percutaneous organs, in particular their extracellular matrix mediating the "device"/epithelium interface, serve as exquisite examples to inspire longer lasting long-term percutaneous device design. For example, the tooth's imperviousness to infection is mediated by the epithelium directly surrounding it, the junctional epithelium (JE). The hallmark feature of JE is formation of hemidesmosomes, cell/matrix adhesive structures that attach surrounding oral gingiva to the tooth's enamel through a basement membrane. Here, the authors survey the multifaceted functions of the JE, emphasizing the role of the matrix, with a particular focus on hemidesmosomes and their five main components. The authors highlight the known (and unknown) effects dental implant - as a model percutaneous device - placement has on JE regeneration and synthesize this information for application to other percutaneous devices. The authors conclude with a summary of bioengineering strategies aimed at solving the percutaneous device dilemma and invigorating greater collaboration between clinicians, bioengineers, and matrix biologists.

Novel use of chloro-aluminum phthalocyanine assisted photodynamic therapy helps in periimplant healing among smoking patients

AIMS

To evaluate the clinical and biochemical peri‑implant parameters using chloro‑aluminum phthalocyanine-(CAP) mediated antimicrobial photodynamic therapy (PDT) as an adjunct to non-surgical mechanical debridement (NSD) in cigarette smokers (CS) and never-smokers (NS) with peri‑implantitis.

MATERIALS AND METHODS

Thirty-two patients with peri‑implantitis [Group CS - 16 and Group NS - 16] were recruited for the trial. The study participants underwent two therapies: PDT + NSD and NSD alone. The clinical peri‑implant parameters assessed in this clinical trial were bleeding on probing (BP), crestal bone loss (CBL) peri‑implant pocket depth (PD), and peri‑implant plaque scores (PS), respectively. Peri-implant crevicular fluid was sampled and the quantification of interleukin (IL)-1β and tumor necrosis factor-alpha (TNF-α) was performed using enzyme linked immunosorbent assay (ELISA).

RESULTS

BP was significantly reduced at 6 months after PDT+NSD in CS groups. Mean PD significantly reduced after both PDT+NSD and NSD subgroups within both NS and CS groups. Only at 6 months did PDT+NSD showed statistically significantly reduced IL-1β levels in the NS group. TNF-α levels significantly reduced in CS group with PDT+NSD and NSD alone at both 3 months and 6 months follow up.

CONCLUSION

CAP-assisted PDT helped to improve the clinical and cytokine levels after non-surgical peri‑implant mechanical debridement in treating peri‑implantitis patients in smokers.

The Characteristics of Microbiome and Cytokines in Healthy Implants and Peri-Implantitis of the Same Individuals

AIM

To characterize the profile of submucosal microbiome and cytokine levels in peri-implant crevicular fluid (PICF) from clinically healthy implants and peri-implantitis in the same individuals.

MATERIAL AND METHODS

A total of 170 patients were screened and, finally, 14 patients with at least one healthy implant and one peri-implantitis implant were included. Submucosal microbiota and cytokines from 28 implants were analyzed using 16S rRNA gene sequencing and multifactor assays, respectively. Correlations of clinical indexes and microbiota or cytokines were analyzed using Spearman's correlation coefficient. A random forest classification model was constructed.

RESULTS

Peri-implantitis sites harbored higher microbial diversity, as well as more Gram-negative bacteria and anaerobic bacteria, compared with healthy implants sites. The genera of Peptostreptococcaceae XIG-1, Treponema, Porphyromonas, and Lachnospiraceae G-8, as well as the cytokines of IL-17A, IL-6, IL-15, G-CSF, RANTES, and IL-1β were significantly higher in peri-implantitis than healthy implants. Furthermore, these genera and cytokines had positive relationships with clinical parameters, including probing depth (PD), bleeding on probing (BOP), and marginal bone loss (MBL). The classification model picked out the top 15 biomarkers, such as IL-17A, IL-6, IL-15, VEGF, IL-1β, Peptostreptococcaceae XIG-1, Haemophilus, and Treponema, and obtained an area under the curve (AUC) of 0.85.

CONCLUSIONS

There are more pathogenic bacteria and inflammatory cytokines in peri-implantitis sites, and biomarkers could facilitate the diagnosis of peri-implantitis.

Does implant location influence the risk of peri-implantitis?

Peri-implantitis is characterized by nonreversible and progressive loss of supporting bone and is associated with bleeding and/or suppuration on probing. Peri-implant disease is considered as the main etiologic factor related to implant failure. Peri-implant disease has a pathogenesis similar to that of periodontal disease, both being triggered by an inflammatory response to the biofilm accumulation. Although the prevalence of peri-implantitis has been evaluated by several clinical studies with different follow-ups, there are currently little data on the impact of implant location and the prevalence of peri-implantitis. The aim of this review, therefore, was to summarize the evidence concerning the prevalence of peri-implantitis in relation to implant location and associated risk predictors. Even though most studies evaluating the prevalence of peri-implantitis in relation to implant location are cross-sectional or retrospective, they suggest that the occurrence of peri-implantitis is most prevalent in the anterior regions of the maxilla and mandible. Moreover, it seems that there is a higher prevalence of peri-implantitis in the maxilla than in the mandible.

Antibacterial and Anti-Inflammatory Properties of a Novel Antimicrobial Peptide Derived from LL-37

Peri-implantitis is a pathological condition involving tissues around dental implants that are characterized by inflammation of the peri-implant mucosa and progressive loss of supporting bone. We found that the antimicrobial peptide KR-12-3 (KRIVKWIKKFLR) derived from LL-37 had antibacterial properties against Streptococcus gordonii. The purpose of this study was to evaluate its antibacterial and anti-inflammatory activities and its underlying mechanisms. We evaluated the antibacterial activities of antimicrobial peptides in planktonic and biofilm states by measuring their minimum inhibitory concentration, minimum bactericidal concentration, and biofilm susceptibility. The effects of antimicrobial peptides on the production of IL-6 and IL-8 in LPS-stimulated RAW264.7 cells were detected by enzyme-linked immunosorbent assay and other experiments, and their toxicity to MC3T3-E1 cells was also studied. While maintaining low cytotoxicity, KR-12-3 exhibited growth inhibitory effects on S. gordonii in planktonic and biofilm states. Lower concentrations of KR-12-3 treatment reduced the production of inflammatory cytokines in LPS-stimulated RAW264.8 cells. The mechanisms underlying the inhibition of biofilm formation and anti-inflammatory effects have been associated with the low expression of related genes. KR-12-3 may be used to develop an antibacterial, anti-infective, and anti-inflammatory drugs for peri-implantitis.