Peri-implant diseases: diagnosis and risk indicators

Zirconia Dental Implants Surface Electric Stimulation Impact on Staphylococcus aureus

Tooth loss during the lifetime of an individual is common. A strategy to treat partial or complete edentulous patients is the placement of dental implants. However, dental implants are subject to bacterial colonization and biofilm formation, which cause an infection named peri-implantitis. The existing long-term treatments for peri-implantitis are generally inefficient. Thus, an electrical circuit was produced with zirconia (Zr) samples using a hot-pressing technique to impregnate silver (Ag) through channels and holes to create a path by LASER texturing. The obtained specimens were characterized according to vitro cytotoxicity, to ensure ZrAg non-toxicity. Furthermore, samples were inoculated with Staphylococcus aureus using 6.5 mA of alternating current (AC). The current was delivered using a potentiostat and the influence on the bacterial concentration was assessed. Using AC, the specimens displayed no bacterial adhesion (Log 7 reduction). The in vitro results presented in this study suggest that this kind of treatment can be an alternative and promising strategy to treat and overcome bacterial adhesion around dental implants that can evolve to biofilm.

CXCL5/CXCL8 induces neutrophilic inflammation in peri-implantitis

OBJECTIVE AND BACKGROUND

This research aimed to examine the role of C-X-C motif chemokine ligand 5 (CXCL5) and C-X-C motif chemokine ligand 8 (CXCL8; also known as IL-8) in neutrophilic inflammation triggered by peri-implantitis and to shed light on the underlying mechanisms that link them to the development of this condition.

MATERIALS

This study included 40 patients who visited the Department of Periodontology at Kyungpook University Dental Hospital. They were divided into two groups based on their condition: healthy implant (HI) group (n = 20) and peri-implantitis (PI) group (n = 20). Biopsy samples of PI tissue were collected from the patients under local anesthesia. HI tissue was obtained using the same method during the second implant surgery. To construct libraries for control and test RNAs, the QuantSeq 3' mRNA-Seq Library Prep Kit (Lexogen, Inc., Austria) was used according to the manufacturer's instructions. Samples were pooled based on representative cytokines obtained from RNA sequencing results and subjected to Reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Hematoxylin and eosin staining, and immunohistochemistry (IHC) analysis were performed to visually assess expression levels and analyze tissue histology. Student's t-test was employed to conduct statistical analyses.

RESULTS

Initially, heatmaps were used to examine gene expression variations between the HI and PI groups based on the results of RNA sequencing. Notably, among various cytokines, CXCL5 and CXCL8 had the highest expression levels in the PI group compared with the HI group, and they are known to be associated with inflammatory responses. In the gingival tissues, the expression of genes encoding cytokines such as interleukin (IL)-1β, tumor necrosis factor-alpha (TNF)-α, interleukin (IL)-6, and CXCL5/CXCL8 was assessed via RT-qPCR. The mRNA expression level of CXCL5/CXCL8 significantly increased in the PI group compared with the HI group (p < .045). Contrarily, the mRNA expression level of interleukin 36 receptor antagonist (IL36RN) significantly decreased (p < .008). IHC enabled examination of the distribution and intensity of CXCL5/CXCL8 protein expression within the tissue samples. Specifically, increased levels of CXCL5/CXCL8 promote inflammatory responses, cellular proliferation, migration, and invasion within the peri-implant tissues. These effects are mediated through the activation of the PI3K/Akt/NF-κB signaling pathway.

CONCLUSIONS

This study found that the PI sites had higher gene expression level of CXCL8/CXCL5 in the soft tissue than HI sites, which could help achieve more accurate diagnosis and treatment planning.

Assessing the quality of YouTube™ videos on fixed dental implant home-care and maintenance protocols

OBJECTIVES

The implant's supporting structure differs from that of the teeth when plaque accumulates, making it more prone to inflammation and bone loss. To ensure the implant's longevity, an effective maintenance protocol should be followed. This study aimed to evaluate the information on oral hygiene procedures at home for implant-supported fixed prosthesis.

METHODS

The keywords 'cleaning dental implant,' 'how to clean dental implant,' and 'dental implant hygiene' used to search for videos on YouTube™. Following the exclusions, two researchers independently analysed the remaining 100 videos for demographic data and content usefulness.

RESULTS

In terms of usefulness score distribution, 53.52% of the videos were considered slightly useful, 38.4% moderately useful and 8.1% very useful. The video content had the least quantity of knowledge about toothpaste choice (11.1%), but the greatest quantity of knowledge on flossing (68.7%).

CONCLUSIONS

According to the study's findings, there is presently no evidence-based information on YouTube™ on dental implant oral hygiene protocols for home care procedures hygiene education. Therefore, dental care professionals should analyse the information's quality and reliability before recommending it to patients.

Evaluation of salivary stress markers and inflammatory cytokine levels in peri-implantitis patients

BACKGROUND AND OBJECTIVE

Psychological stress has been identified in some observational studies as a potential factor that may modify and affect periodontal diseases, but there are no similar data for peri-implantitis. The aim of this study was to determine the relationship between interleukin (IL)-1β, IL-6, IL-10, interferon (IFN)α inflammatory cytokines and the psychological stress-related markers, glucocorticoid receptor-α (GRα), and salivary α-amylase (sAA) gene expression levels in saliva samples obtained from healthy implants and peri-implantitis patients.

MATERIALS AND METHODS

The study included a total of 50 systemically healthy subjects. Peri-implant clinical parameters were recorded and psychological stress level was evaluated with the hospital anxiety and depression scale (HAD) and state-trait anxiety inventory (STAI) questionnaire forms. Following the evaluations, the patients were divided into 4 groups according their stress and clinical status (Ia, Ib, IIa, IIb). IL-1β, IL-6, IL-10, IFNα, GRα, sAA gene expression levels in the saliva samples were quantified by quantitative polymerase chain reaction (qPCR).

RESULTS

In the group of peri-implantitis who had a high score in stress level assessment scales, significantly higher IL-1β, IL-6, sAA expression levels were observed (p < 0.001). The IL-10 gene expression levels were lower in the groups with a high score in the stress level assessment scales (p < 0.001). GRα gene was expressed at lower levels in the group of peri-implantitis who had a high score in stress level assessment scales but the difference was not statistically significant (p = 0.065).

CONCLUSION

The study findings suggest that psychological stress may increase the inflammation associated with peri-implantitis by affecting cytokine expression levels.

CLINICAL RELEVANCE

To prevent peri-implantitis or reduce its prevalence, it could be beneficial to evaluate stress levels and identify individuals experiencing stress.

Efficacy of adjunctive photodynamic therapy to conventional mechanical debridement for peri-implant mucositis

OBJECTIVE

This meta-analysis was conducted to assess the effectiveness of photodynamic therapy (PDT) as an adjunct to conventional mechanical debridement (CMD) for the management of peri-implant mucositis (p-iM).

METHODS

We systematically searched four databases (PubMed, Embase, Web of Science, and Cochrane Library) for randomized controlled trials (RCTs) investigating PDT + CMD for p-iM from their inception to March 13, 2023. Meta-analysis was performed using RevMan 5.4 software.

RESULTS

Seven RCTs met the inclusion criteria. The meta-analysis revealed that PDT + CMD treatment was more effective than CMD alone in reducing probing depth (PD) (Mean Difference [MD]: -1.09, 95% Confidence Interval [CI]: -1.99 to -0.2, P = 0.02) and plaque index (PI) (MD: -2.06, 95% CI: -2.81 to -1.31, P < 0.00001). However, there was no statistically significant difference in the improvement of bleeding on probing (BOP) between the PDT + CMD groups and CMD groups (MD: -0.97, 95% CI: -2.81 to 0.88, P = 0.31).

CONCLUSIONS

Based on the current available evidence, this meta-analysis indicates that the addition of PDT to CMD significantly improves PD and PI compared to CMD alone in the treatment of p-iM. However, there is no significant difference in improving BOP.

The cumulative survival rate of sandblasted, large-grit, acid-etched dental implants: a retrospective analysis

PURPOSE

This retrospective study aimed to assess the long-term cumulative survival rate of titanium, sandblasted, large-grit, acid-etched implants over a 10-year follow-up period and investigate the factors affecting the survival rate and change in marginal bone loss (MBL).

METHODS

The study included 400 patients who underwent dental implant placement at the Department of Periodontology of Seoul National University Dental Hospital (SNUDH) between 2005 and 2015. Panoramic radiographic images and dental records of patients were collected and examined using Kaplan-Meier analysis, Cox proportional hazards regression analysis, and multiple regression analysis to determine the survival rates and identify any factors related to implant failure and MBL.

RESULTS

A total of 782 implants were placed with a follow-up period ranging from 0 to 16 years (mean: 8.21±3.75 years). Overall, 25 implants were lost, resulting in a cumulative survival rate of 96.8%. Comparisons of the research variables regarding cumulative survival rate mostly yielded insignificant results. The mean mesial and distal MBLs were 1.85±2.31 mm and 1.59±2.03 mm, respectively. Factors influencing these values included age, diabetes mellitus (DM), jaw location, implant diameter, bone augmentation surgery, and prosthetic unit.

CONCLUSIONS

This study found that the implant survival rates at SNUDH fell within the acceptable published criteria. The patients' sex, age, DM status, implant location, implant design, implant size, surgical type, bone augmentation, and prosthetic unit had no discernible influence on long-term implant survival. Sandblasted, large-grit, acid-etched implants might offer advantages in terms of implant longevity and consistent clinical outcomes.

Biocompatibility of dental implants coated with hydroxyapatite using pulsed Er:YAG laser deposition

We aimed to improve the biocompatibility and osteoinductive potential of Ti implants using a simulated intraoral hydroxyapatite (HAp) coating. We devised a novel surface treatment for aggressive induction of osteoblast adhesion and bone regeneration on the implant surface. A thin α-tricalcium phosphate (α-TCP) film was deposited on the implant surface using a pulsed Er:YAG laser. The coating was converted to HAp through artificial saliva immersion, which was confirmed using scanning electron microscopy (SEM) and X-ray diffraction (XRD). SEM showed needle-like HAp crystals on the Ti disks and sandblasted implant surfaces after immersion in artificial saliva for 96 h. Microcomputed tomography and histological evaluation 4 and 8 weeks after implantation into beagle dog mandibles showed that the HAp-coated implant was biocompatible and exhibited superior osteoinduction compared to that of sandblasted implants. Coating the implant surface with HAp using an Er:YAG laser has potential as a new method of the implant-surface debridement.

Association of Peri-Implant Keratinized Mucosa Width and Mucosal Thickness with Early Bone Loss: A Cross-Sectional Study

Objective: The objective of this study was to evaluate the effects of keratinized mucosa width (KMW) and mucosal thickness (MT) around dental implants on marginal bone loss (MBL). The evaluation was performed one year after loading by comparing clinical, radiographic, and biochemical parameters. Methods: The study included 87 implants in 87 patients undergoing regular follow-ups without hard or soft tissue augmentation one year after loading. Clinical measurements included plaque index (PI), gingival index (GI), bleeding on probing (BoP), probing depth (PD), KMW, and MT. MBL was assessed with periapical radiography. The peri-implant crevicular fluid (PICF) was analyzed for tumor necrosis factor-alpha (TNF-α), receptor activator of nuclear factor-kB ligand (RANKL), osteoprotegerin (OPG), and microRNA-27a. Results: The MBL of implants with thin MT (<2 mm) was higher than that of implants with thick MT (≥2 mm) (p < 0.05). A significant negative correlation (r: -0.217) was established between MT and MBL. No significant association was found between KMW and MBL (p > 0.05). No significant associations was found between KMW and MT with TNF-α, RANKL, OPG and RANKL/OPG (p > 0.05), with the exception of increased microRNA-27a levels in implants with KMW ≥ 2 mm (p < 0.05). Conclusions: Implants with a thick MT had a lower MBL. There may be an association between adequate KMW and high miRNA-27a levels. The relationship between MBL and miRNA-27a remains unclear.

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.

Awareness of peri-implantitis among general dental practitioners in the UK: a questionnaire study

Introduction Dental implants are a predictable prosthetic option for replacement of missing teeth with good survival rates. Peri-implant diseases are the main reason for implant failure by causing bone loss around the implant leading to implant loss. General dental practitioners see patients with dental implants routinely and therefore, awareness of risk factors for peri-implant disease and early diagnosis is essential for appropriate management. The aim of this study is to assess the awareness of general dental practitioners in diagnosing peri-implantitis, with a view to identify any potential training needs.Design, setting, materials and methods A quantitative study method was designed using an online questionnaire sent to closed social media groups in the UK. The significance level was taken as p <0.05. The chi-squared tests and Kruskal-Wallis tests were used with IBM SPSS software. Descriptive statistical analysis of data was also done.Results and conclusion A total of 224 responses were received. The results show that there is lack of awareness of diagnostic criteria of peri-implantitis among general dental practitioners. However, majority of practitioners are aware of the legal implications of failing to diagnose this condition. There is a perceived need for more undergraduate training in diagnosing peri-implant diseases.

Clinical, immunological and microbiological evaluation of experimental peri-implant mucositis and gingivitis in subjects with Grade C, stage III/IV periodontitis background

AIM

To compare individuals with a periodontitis background (Grade C, stage III/IV-formerly generalized aggressive periodontitis) (H-GAP) with periodontally healthy subjects (H-Health) in terms of molecular changes (immunological/microbiological) accompanying experimental peri-implant mucositis and gingivitis.

MATERIALS AND METHODS

H-GAP and control (H-Health) subjects were recruited, and experimental mucositis/gingivitis was induced around a single screw-retained implant and one contralateral tooth. Participants refrained from oral hygiene for 21 days in the selected areas, followed by professional prophylaxis and hygiene instructions for 21 days. Clinical parameters, immunological markers (multiplex analysis) and microbial data (16S rRNA gene sequencing) were collected at baseline, during induction (7, 14 and 21 days) and following remission (42 days).

RESULTS

Clinically, no significant differences were observed between the groups (n = 10/each group) (H-GAP vs. H-Health) (p > .05, Mann-Whitney test) and the type of site (tooth vs. implant) (p > .05, Wilcoxon test) at the time of onset and resolution, or severity of gingival/mucosal inflammation. H-GAP displayed lower concentrations of the cytokines interleukin (IL)-1B, IL-4, IL-17, tumor necrosis factor-α and interferon-γ around implants than H-Health at baseline and during induction of mucositis (p < .05, Mann-Whitney test). In both groups, implants showed significantly higher inflammatory background at baseline and all subsequent visits when compared with teeth (p < .05, Wilcoxon test). Alpha and β-diversity metrics showed a significant shift in the microbiome composition and abundances of core species during induction and resolution of peri-implant mucositis and gingivitis (p < .05, restricted maximum likelihood method of Shannon and Bray-Curtis indices, respectively). Differences were not significant for these parameters between the H-Health and H-GAP groups when the periodontal and peri-implant microbiomes were compared separately; however, at each time point, the peri-implant microbiome differed significantly from the periodontal microbiome.

CONCLUSIONS

Within the limitations of this pilot study (e.g. low power), it can be concluded that different microbial shifts contribute to the onset and progression of inflammatory responses around teeth and implants and that history of periodontal disease experience plays an additional role in modulating the immune response of peri-implant and periodontal tissues to biofilm accumulation.

Single-cell sequencing identifies inflammation-promoting fibroblast-neutrophil interaction in peri-implantitis

AIM

To reveal the cellular composition and molecular environment of the periodontal and peri-implant inflammatory infiltrates through a single-cell sequencing technique, which may explain the pathological difference between these two diseases. A special focus was placed on the phenotypes and potential roles of neutrophils and fibroblasts in peri-implant/periodontal tissue immunity.

MATERIALS AND METHODS

High-throughput single-cell transcriptomic profiling of peri-implant tissues from patients with peri-implantitis as well as periodontal tissues from patients with periodontitis and healthy donors was performed. Immunofluorescence analysis was carried out to further validate the identified cell subtypes and their involvement in peri-implantitis and periodontitis.

RESULTS

Based on our single-cell resolution analysis, a quantified proportional increase of neutrophil (Neu) subtypes was shown in peri-implantitis. Among these, a predominance of Neutro_CXCR2 was revealed. We also found the involvement of inflammation-promoting fibroblasts as well as a predominance of CXCL8+ fibroblast-CXCR2+ neutrophil interaction in peri-implantitis.

CONCLUSIONS

Our study indicated that the predominance of CXCL8+ fibroblast-CXCR2+ neutrophil interaction might underline the enhanced host response in peri-implantitis compared with periodontitis. This information offers a molecular basis by which fibroblast and neutrophil subtypes might be diagnostically and therapeutically targeted in peri-implantitis.

Serum TNF-α level and probing depth as a combined indicator for peri-implant disease

Peri-implant disease (PID) is a general term for inflammatory diseases of soft and hard tissues that occur around implants, including peri-implant mucositis and peri-implantitis. Cytokines are a class of small molecule proteins, which have various functions such as regulating innate immunity, adaptive immunity, and repairing damaged tissues. In order to explore the characteristics and clinical significance of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, and tumor growth factor (TGF)-β1 expression levels in serum of patients with peri-implant disease, 31 patients with PID and 31 patients without PID were enrolled. The modified plaque index (mPLI), modified sulcus bleeding index (mSBI), and peri-implant probing depth (PD) were recorded. The levels of serum TNF-α, IL-6, IL-10, and TGF-β1 were detected by ELISA. TNF-α, mPLI, mSBI, and PD levels were significantly higher in the PID group. TGF-β1 levels were significantly higher in the control group. There was a significant positive correlation between TNF-α and mPLI, mSBI, and PD. TGF-β1 was negatively associated with TNF-α, mPLI, mSBI, and PD. Multiple logistic regression analysis showed that TNF-α and PD were risk factors for the severity of PID. The receiver operating curve analysis showed that high TNF-α levels (cut-off value of 140 pg/mL) and greater PD values (cut-off value of 4 mm) were good predictors of PID severity with an area under the curve of 0.922. These results indicated that TNF-α and PD can be used as a biological indicator for diagnosing the occurrence and progression of PID.

Metagenomic analysis of healthy and diseased peri-implant microbiome under different periodontal conditions: a cross-sectional study

BACKGROUND

Peri-implantitis is a polybacterial infection that can lead to the failure of dental implant rehabilitation. This study aimed to profile the microbiome of the peri-implant plaque and estimate the effect of periodontitis on it among 40 Chinese participants with dental implant prostheses and presenting with varying peri-implant and periodontal health states.

METHODS

Submucosal plaque samples were collected from four distinct clinical categories based on both their implant and periodontal health status at sampling point. Clinical examinations of dental implant and remaining teeth were carried out. Metagenomic analysis was then performed.

RESULTS

The microbiome of the peri-implantitis sites differed from that of healthy implant sites, both taxonomically and functionally. Moreover, the predominant species in peri-implantitis sites were slightly affected by the presence of periodontitis. T. forsythia, P. gingivalis, T. denticola, and P. endodontalis were consistently associated with peri-implantitis and inflammatory clinical parameters regardless of the presence of periodontitis. Prevotella spp. and P. endodontalis showed significant differences in the peri-implantitis cohorts under different periodontal conditions. The most distinguishing function between diseased and healthy implants is related to flagellar assembly, which plays an important role in epithelial cell invasion.

CONCLUSIONS

The composition of the peri-implant microbiome varied in the diseased and healthy states of implants and is affected by individual periodontal conditions. Based on their correlations with clinical parameters, certain species are associated with disease and healthy implants. Flagellar assembly may play a vital role in the process of peri-implantitis.

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.

Knowledge and attitude of dental students regarding etiology, diagnosis, and treatment of peri-implantitis

OBJECTIVE

The objective of this study was to assess the level of knowledge and attitude of dental students about the etiology, diagnosis, and management of peri-implantitis.

METHODS

An online cross-sectional study that targeted senior undergraduate dental students at the College of Dentistry was conducted. A closed-ended survey consisting of 28 questions was designed. Three sections were created: 1) participants' characteristics; 2) Knowledge of peri-implantitis etiology, risk factors, diagnosis, and complications; 3) The use of antibiotics in peri-implantitis, diagnosis, and treatment methods. SPSS version 22 (IBM Corp.) was used for data analysis. Counts and percentages were calculated for correct answers in each section.

RESULTS

A total of 267 dental students responded to the questionnaire. The majority of the participants (81.6%) were knowledgeable about peri-implantitis being an inflammatory reaction, and a lesser percentage (77.9%) knew that bacterial plaque is an etiologic factor for peri-implant diseases. 82.0% of the participants identified smoking as a risk factor, followed by periodontitis (80.5%). Regarding implant complications, 57.3% of the participants considered implant mobility as a definitive indication for implant removal. More than half of the participants reported using crater-like bone defects surrounding implants to diagnose peri-implantitis. The most commonly used antibiotic was amoxicillin (34.1%), followed by amoxicillin combined with metronidazole (26.9%).

CONCLUSION

Most participants had a basic understanding of the etiology and risk factors of peri-implantitis. On the other hand, more courses addressing peri-implantitis diagnosis are needed.

How Can Imbalance in Oral Microbiota and Immune Response Lead to Dental Implant Problems?

Dental implantology is one of the most dynamically developing fields of dentistry, which, despite developing clinical knowledge and new technologies, is still associated with many complications that may lead to the loss of the implant or the development of the disease, including peri-implantitis. One of the reasons for this condition may be the fact that dental implants cannot yield a proper osseointegration process due to the development of oral microbiota dysbiosis and the accompanying inflammation caused by immunological imbalance. This study aims to present current knowledge as to the impact of oral microflora dysbiosis and deregulation of the immune system on the course of failures observed in dental implantology. Evidence points to a strong correlation between these biological disturbances and implant complications, often stemming from improper osseointegration, pathogenic biofilms on implants, as well as an exacerbated inflammatory response. Technological enhancements in implant design may mitigate pathogen colonization and inflammation, underscoring implant success rates.

Evaluation of implants in smoking and non-smoking patients with peri-implant disease risk analysis and esthetic scores: an observational study

BACKGROUND

This study examined how smoking affects esthetics, peri-implant health, gingiva around the implant, and implant disease risk assessment in patients with implants.

METHODS

The study included two hundred ninety-eight implants of systemically healthy patients aged between 38 and 62 who applied to the Periodontology Clinic and whose functionally prosthesis-loaded implants had been at least six months and at most five years old. Implants of patients with bruxism were not included in the study. Implants are divided into two according to the patient's smoking. Vestibule depth around the implant, keratinized gingival thickness and width, gingival recession, bleeding on probing, pocket depth, and gingival index by a sole clinician. The pink esthetic score, peri-implant disease risk assessment, and implant health scale were also examined to measure implant esthetics and success.

RESULTS

There was a statistically significant difference in the implant disease risk assesment scores for the examined implants of smokers and nonsmokers (p < 0.05). People who had peri-implantitis had higher implant disease risk assesment score levels. The dental implant health scale revealed a statistically significant difference (p < 0.05) in the likelihood of implant disease. According to the dental implant health scale, dental implants were 100% successful for non-smokers. There was a significant difference in the keratinized gingiva width between smokers and nonsmokers (p < 0.05). The results of the study showed that nonsmokers had a wider keratinized gingiva.

CONCLUSIONS

Research has demonstrated that the act of smoking has the potential to jeopardize the long-term survival of dental implants and the surrounding peri-implant tissues. The results of this study indicate that it would be advisable for dentists to provide guidance to their patients on smoking cessation and to monitor any alterations in behavior closely. Furthermore, it would be advantageous for dental professionals to elucidate the impact of smoking on the susceptibility of smokers to peri-implant disease.

Plaque accumulation on the fitting surface of full-arch implant-supported fixed prostheses with contact or noncontact pontics: A split mouth randomized controlled trial

OBJECTIVE

To explore the differences in plaque accumulation on the fitting surface of full-arch implant-supported fixed prostheses with contact or noncontact pontics.

MATERIALS AND METHODS

Nineteen patients (20 prostheses, 7 in the maxilla, and 13 in the mandible) intending to undergo full-arch implant-supported immediate function prostheses were recruited. During immediate restoration and using the midline as the boundary, one side was restored as a pontic and mucosa noncontact type (the test group), and the opposite side was restored as a pontic and mucosa contact type (the control group). In a follow-up 6 months after the surgery, the cleanliness of the fitting surface of the immediate prosthesis was evaluated by plaque staining and debris index determination. Patient satisfaction was investigated by questionnaire.

RESULTS

Twenty prostheses from 19 patients included in the randomized controlled trial were followed up. Among the 20 prostheses, the percentage of area covered with plaque was significantly lower in the test group compared with that in the control group (31.5 ± 15.8% vs. 43.7 ± 15.3%; p < 0.001). The debris index in the test group was lower than that in the control group, although the difference was not statistically significant (2.77 ± 0.73 vs. 3.15 ± 0.90; p > 0.05). In the patient satisfaction survey, most of the patients were satisfied with most aspects of the prostheses, however, nearly half of the patients were not satisfied with the cleaning.

CONCLUSIONS

The pontic and mucosa noncontact prosthetic design reduces plaque accumulation on the fitting surface, which is beneficial for maintaining oral cleanliness. However, the majority of study samples were mandible and conclusions may not be fully applicable to maxilla.

TRIAL REGISTRATION

www.chictr.org.cn (ChiCTR1900028576).

CLINICAL SIGNIFICANCE

The noncontact design in full-arch implant-supported fixed prostheses may be an effective measure of improving oral hygiene promotion. There is need for more research that can further improve oral hygiene of patients with full-arch implant-supported prostheses.

The importance of soft tissue condition in bone regenerative procedures to ensure long-term peri-implant health

Bone regenerative procedures have been widely proved to be a reliable treatment option to re-create the ideal pre-implant clinical conditions. Nevertheless, these techniques are not free from post-operative complications which might result in implant failure. Consequently, as demonstrated by the increasing recently published evidence, a careful pre- and intra-operative flap evaluation to ensure an ideal and hermetic tension-free wound closure is of paramount importance to successfully treat bony defects. In this respect, several surgical interventions mainly aimed to increase the amount of keratinized mucosa either to allow an optimal healing after a reconstructive procedure or to establish an optimal peri-implant soft tissue seal have been proposed. The present review summarizes the level of evidence on the surgical clinical aspects which have an impact on the soft tissue handling associated with bone reconstructive procedures and on the importance of soft tissue conditions to enhance and maintain peri-implant health in the long-term.

Changes in bone graft height and influencing factors after sinus floor augmentation by using the lateral window approach: A clinical retrospective study of 1 to 2 years

STATEMENT OF PROBLEM

Recent systematic reviews have reported resorption of bone grafts after augmentation, but the influencing factors are numerous and uncertain. Different brands of bone graft and other factors may affect the bone formation effect after sinus floor augmentation.

PURPOSE

The purpose of this retrospective clinical study was to evaluate the graft material height changes after sinus floor augmentation with cone beam computed tomography (CBCT) and to investigate the potential influencing factors related to graft resorption.

MATERIAL AND METHODS

Four midsagittal cut CBCT images of 157 posterior maxillary implants after maxillary sinus floor elevation by using the lateral window approach with bone grafts from 116 patients were obtained. Four CBCT scans had been performed immediately (T0), 6 months (T1) and 12 months after bone grafting (T2), and 1.5 to 2 years after treatment (T3), and the distance between the implant platform and the grafted mucosa of the maxillary sinus floor was measured at 3 locations. Correlation coefficients of these parameters were calculated. A linear mixed model was used to investigate potential factors influencing graft height reduction, including the patient's sex, age, smoking status, periodontal status, graft brand, implant site, implant level, placement time, and residual bone height.

RESULTS

Mean ±standard deviation graft height at the mesial side of the implant (MeGH) was significantly decreased by 0.32 ±0.88 mm in the first 6 months, was gradually reduced after 6 months (0.26 ±0.43 mm), and then 1 to 2 years later increased to 0.39 ±0.97 mm. The changes in graft height at the center of the implant (CeGH) and graft height at the distal side (DiGH) groups were similar to those in the MeGH group. A significantly positive correlation was found among the height alterations in 3 locations (rs=0.954, P<.001). The linear mixed model showed that smoking was more likely to cause graft height reduction in MeGH (P=.034).

CONCLUSIONS

Graft height significantly decreased after maxillary sinus augmentation over 1 to 2 years. Smoking had a negative effect on graft height changes, while the 2 brands of graft and other factors had no significant effect.

Dentists' perceptions and usability testing of the implant disease risk assessment IDRA, a tool for preventing peri‑implant disease: A qualitative study

INTRODUCTION

we aimed to explore dentists' perceptions toward the implementation of a dental informatics risk assessment tool which estimates the risk for a patient to develop peri‑implantitis.

MATERIALS AND METHODS

the Implant Disease Risk Assessment Tool (IDRA) was presented to a convenience sample of seven dentists working in a university clinic, whom were asked to use IDRA with the information of three clinical cases whilst thinking aloud and then fill the System Usability Scale (SUS). A semi-structured interview technique was used with audio record to allow free expression of participants' perceptions related to the IDRA. The interviews information was categorized and analyzed by the authors.

RESULTS

to our knowledge, this is the first study conducted to develop a qualitative usability test of IDRA, evaluating the effectiveness, efficiency, and users' satisfaction. There were more variations in responses the greater the degree of complexity of the clinical case. Generally, the participants classified the tool as good, getting usability values of 77,2 (SD 19,8) and learnability 73,2 (SD 24,5).

CONCLUSION

four additional factors should be considered to improve IDRA tool: 1) considering the relation between contour angle and peri-implant tissue height; 2) automatic periodontal classification in the IDRA tool after completing the periodontogram in the clinical software; 3) presentation of a flowchart to assist therapeutic decisions alongside the final score defined by the IDRA tool; 4) integrating of precision tests such as Implantsafe® DR… (dentognostics gmbh, Jena) and Oralyzer®(dentognostics gmbh, Jena).

CLINICAL SIGNIFICANCE

etiology and pathogenesis of peri‑implant diseases is multifactorial. These tools must follow a natural integration to be easily applied in a clinical setting. It is important to study their usability from the clinicians' point of view, evaluating the effectiveness, efficiency, and users' satisfaction.

Risk indicators associated with peri-implant diseases: a retrospective cross-sectional study of Colombian patients with 1 to 18 years of follow-up

PURPOSE

Peri-implant mucositis (PIM) and peri-implantitis (PI) are multicausal conditions with several risk factors contributing to their pathogenesis. In this study, we retrospectively investigated risk variables potentially associated with these peri-implant diseases (PIDs) over a follow-up period of 1 to 18 years.

METHODS

The study sample consisted of 379 implants placed in 155 patients. Single-visit clinical and radiographic evaluations were employed to determine the presence or absence of PIDs. Parameters related to the patient, site, surgery, implant, and prosthetic restoration were documented. The relationships between risk variables and the occurrence of PIDs were individually examined and adjusted for confounders using multivariate binary logistic regression models.

RESULTS

The prevalence rates of PIM and PI were 28.4% and 36.8% at the patient level and 33.5% and 24.5% at the implant level, respectively. Poor oral hygiene, active gingivitis/periodontitis, preoperative alveolar ridge deficiency, early or delayed implant placement, implant length of 11.0 mm or less, and poor restoration quality were strong and independent risk indicators for both PIDs. Furthermore, a follow-up period of more than 5 years and a loading time of more than 4 years were important indicators for PI. Simultaneously, age and smoking status acted as modifiers of the effect of mesiodistal (MD) and buccolingual (BL) widths of restoration on PI.

CONCLUSIONS

In this study population, oral hygiene, periodontal status, preoperative alveolar ridge status, implant placement protocol, implant length, and the quality of coronal restoration appear to be robust risk indicators for both PIM and PI. Additionally, the length of follow-up and functional loading time are robust indicators of PI. Furthermore, the potential modifying relationships of age and smoking status with the MD and BL widths of restoration may be crucial for the development of PI.

Efficacy of adjuvant metronidazole therapy on peri-implantitis: a systematic review and meta-analysis of randomized clinical studies

Peri-implant diseases are pathological conditions that affect the survival of dental implants. Etiological studies are limited, accepting a prevalence of 20% at the implant level and 24% at the patient level. The benefits of adjuvant metronidazole are controversial. A systematic review and meta-analysis of RCTs according to PRISMA and PICOS was performed with an electronic search over the last 10 years in MEDLINE (PubMed), WOS, Embase, and Cochrane Library. The risk of bias was measured using the Cochrane Risk of Bias tool and the methodological quality using the Jadad scale. Meta-analysis was performed with RevMan version 5.4.1, based on mean difference and standard deviation, with 95% confidence intervals; the random-effects model was selected, and the threshold for statistical significance was defined as p < 0.05. A total of 38 studies were collected and five were selected. Finally, one of the studies was eliminated because of unanalyzable results. All studies reached a high methodological quality. A total of 289 patients were studied with follow-up periods from 2 weeks to 1 year. Statistical significance was only found, with respect to the use of adjunctive metronidazole, in the pooled analysis of the studies (p = 0.02) and in the analysis of the radiographic values reported on peri-implant marginal bone levels, in the studies with a 3-month follow-up (p = 0.03). Discrepancies in the use of systemic metronidazole require long-term randomized clinical trials (RCTs) to determine the role of antibiotics in the treatment of peri-implantitis.

Corrosion Resistance and Titanium Ion Release of Hybrid Dental Implants

One of the strategies for the fight against peri-implantitis is the fabrication of titanium dental implants with the part close to the neck without roughness. It is well known that roughness favors osseointegration but hinders the formation of biofilm. Implants with this type of structure are called hybrid dental implants, which sacrifice better coronal osseointegration for a smooth surface that hinders bacterial colonization. In this contribution, we have studied the corrosion resistance and the release of titanium ions to the medium of smooth (L), hybrid (H), and rough (R) dental implants. All implants were identical in design. Roughness was determined with an optical interferometer and residual stresses were determined for each surface by X-ray diffraction using the Bragg-Bentano technique. Corrosion studies were carried out with a Voltalab PGZ301 potentiostat, using Hank's solution as an electrolyte at a temperature of 37 °C. Open-circuit potentials (Eocp), corrosion potential (Ecorr), and current density (icorr) were determined. Implant surfaces were observed by JEOL 5410 scanning electron microscopy. Finally, for each of the different dental implants, the release of ions into Hank's solution at 37 °C at 1, 7, 14, and 30 days of immersion was determined by ICP-MS. The results, as expected, show a higher roughness of R with respect to L and compressive residual stresses of -201.2 MPa and -20.2 MPa, respectively. These differences in residual stresses create a potential difference in the H implant corresponding to Eocp of -186.4 mV higher than for the L and R of -200.9 and -192.2 mV, respectively. The corrosion potentials and current intensity are also higher for the H implants (-223 mV and 0.069 μA/mm²) with respect to the L (-280 mV and 0.014 μA/mm² and R (-273 mV and 0.019 μA/mm²). Scanning electron microscopy revealed pitting in the interface zone of the H implants and no pitting in the L and R dental implants. The titanium ion release values to the medium are higher in the R implants due to their higher specific surface area compared to the H and L implants. The maximum values obtained are low, not exceeding 6 ppb in 30 days.

A Systematic Review and Meta-Analysis of the Clinical Outcomes for Adjunctive Physical, Chemical, and Biological Treatment of Dental Implants With Peri-Implantitis

The present systematic review evaluated the efficacy of adjunctive therapies in the treatment of peri-implantitis. Studies comparing the outcome of conventional surgical- or nonsurgical mechanical debridement with the addition of an adjunctive therapeutic modality were identified through an electronic and hand search of available literature. Following data extraction, meta-analyses were performed on the primary outcome measures. The effects of the adjunctive therapies on bleeding on probing (13 studies), probing pocket depth (9 studies), and radiographic bone level changes (7 studies) were analyzed to evaluate potential clinical benefit. Heterogeneity was expressed as the I2 index. Fixed and random effect models were demonstrated. The potential benefit of adjunctive therapies over control procedures was evaluated in 18 studies, representing a total of 773 implants. Quality assessment of the studies found only 3 studies to be at a low risk of bias. Meta-analysis among the different additional modalities revealed chemical therapy demonstrating significant effects in probing pocket depth reduction (0.58 mm; 0.44-0.72) and radiographic bone level gain (0.54 mm; 0.16-0.92). No significant improvements in bleeding on probing reduction were found using any adjunctive therapy. Available evidence on the benefits of adjunctive therapy to nonsurgical or surgical mechanical debridement in the treatment of peri-implantitis is limited by low numbers of standardized, controlled studies for individual therapies, heterogeneity between studies, and a variety of outcome measures. The lack of effect of any adjunctive therapy in reducing bleeding on probing questions the overall effectiveness over conventional treatment. The long-term clinical benefit potential of these therapies is not demonstrated.

Influence of Section Thickness on the Accuracy and Specificity of Histometric Parameters Using Confocal Laser Scanning Microscopy in a Canine Model of Experimental Peri-Implantitis-A Proof of Concept

OBJECTIVES

Tissue breakdown was assessed by confocal laser scanning microscopy (CLSM) using autofluorescence around implants with ligatures, on a dog hemimandible. Influence of section thickness on the accuracy of histometrical observations was also evaluated, in comparison with thin sections in light microscopy.

MATERIAL AND METHODS

Three months after tooth extraction, implants were placed. Two months after abutment placement, ligatures were placed with no plaque control. 11 months post-implantation, the animal was sacrificed. Undecalcified thin (30 µm) sections were cut, stained and evaluated by light microscopy to be used as a reference. Additional sections were performed, so that another pair of unstained thick sections resulted (250-300 µm). Tissue loss was assessed using histomorphometric parameters under CLSM and was compared to the light microscopy reference ones.

RESULTS

Morphometry confirmed tissue loss more pronounced on the "thick" and quick sections, when compared to the time-consuming and technique-sensitive "thin" ones.

CONCLUSIONS

Within the limits of the present study, the adequacy of histometrical observations under CLSM reveal commensurable information about soft-tissue-bone-implant details, when compared to traditional light microscopy histological protocols. The CLSM investigation may seem demanding, yet the richness of data acquired may justify this approach, provided seatbacks caused by improper manipulation of "thick" sections are avoided.

In vitro efficacy of non-surgical and surgical implant surface decontamination methods in three different defect configurations in the presence or absence of a suprastructure

OBJECTIVES

Analysis of the in vitro efficacy of non-surgical and surgical dental implant surface decontamination with or without suprastructure.

MATERIALS AND METHODS

Three hundred and sixty implants were dipped in indelible red and distributed to 30°, 60°, or 90° angulated bone defect models. One hundred and twenty implants were used for each bone defect, 40 of which were assigned to a decontamination method (CUR: curette; SOSC: soundscaler; APA: air powder abrasion). Of these, 20 were subjected to a simulated non-surgical (NST) or surgical treatment (ST), with/without mucosa mask, of which 10 were carried out with (S+) or without (S-) suprastructure. Uncleaned implant surface was assessed by both-sided implant surface photography. Surface morphology changes were analyzed using scanning electron microscopy (SEM).

RESULTS

Cleaning efficacy was significantly better within NST if the suprastructure was removed (p < 0.001). No significant difference was found within ST (p = 0.304). Overall, cleaning efficacy in the order APA > SOSC>CUR decreased significantly (p < 0.0001) for both S+ and S- in NST as well as ST. Separated by NST/ST, S+/S-, defect angulation and decontamination method, only isolated significant differences in cleaning efficacy were present. Linear regression analysis revealed significant associations of remnants with the treatment approach, decontamination method, and defect angle (p < 0.0001). SEM micrographs showed serious surface damage after use of CUR and SOSC.

CONCLUSIONS

Suprastructure removal is an additional option to improve cleaning efficacy of non-surgical implant surface decontamination in this in vitro model.

Surface Treatments of PEEK for Osseointegration to Bone

Polymers, in general, and Poly (Ether-Ether-Ketone) (PEEK) have emerged as potential alternatives to conventional osseous implant biomaterials. Due to its distinct advantages over metallic implants, PEEK has been gaining increasing attention as a prime candidate for orthopaedic and dental implants. However, PEEK has a highly hydrophobic and bioinert surface that attenuates the differentiation and proliferation of osteoblasts and leads to implant failure. Several improvements have been made to the osseointegration potential of PEEK, which can be classified into three main categories: (1) surface functionalization with bioactive agents by physical or chemical means; (2) incorporation of bioactive materials either as surface coatings or as composites; and (3) construction of three-dimensionally porous structures on its surfaces. The physical treatments, such as plasma treatments of various elements, accelerated neutron beams, or conventional techniques like sandblasting and laser or ultraviolet radiation, change the micro-geometry of the implant surface. The chemical treatments change the surface composition of PEEK and should be titrated at the time of exposure. The implant surface can be incorporated with a bioactive material that should be selected following the desired use, loading condition, and antimicrobial load around the implant. For optimal results, a combination of the methods above is utilized to compensate for the limitations of individual methods. This review summarizes these methods and their combinations for optimizing the surface of PEEK for utilization as an implanted biomaterial.

Evaluation of the significance of keratinized mucosa on peri-implant tissue health: a prospective clinical trial

BACKGROUND

The effect of keratinized mucosa on peri-implant tissue health is still inconclusive. This study aimed to evaluate the importance of keratinized mucosa and investigate the impact of the free gingival graft procedure on peri-implant health.

METHODS

At prosthesis delivery, the implants were allocated into three groups, based on the width of keratinized mucosa (KM) and patients' agreement on the free gingival graft procedure: KMS (KM ≥2 mm), KMD (KM <2 mm), and FGG (KM <2 mm initially and having surgically increased keratinized mucosa). Modified plaque index (mPI), probing depth (PD), modified bleeding index (mBI), KM, and marginal bone loss (MBL) were assessed at the baseline, 6-, 12-, and 24-month follow-up periods.

RESULTS

Of the 47 patients, 17 belonged to the KMS group, 17 belonged to the KMD, and the remaining 13 patients belonged to the FGG. KMD demonstrated significantly fewer mPI and higher mBI than KMS and FGG at 6 and 12 months. At 24 months, MBL did not differ between the groups; however, PD was significantly greater in the KMD group.

CONCLUSIONS

Implants with inadequate keratinized mucosa had higher bleeding and pocket depth values despite less plaque accumulation. According to the results, soft tissue grafting should be performed as early as possible. © 2023 Australian Dental Association.

What every dental practitioner should know about how to examine patients with dental implants

Dental implants are a common treatment modality provided in both primary and secondary care settings. It is increasingly common for a general dental practitioner to see patients with implant-retained restorations. This article suggests an implant safety checklist for general dental practitioners to help them examine an implant-retained prosthesis.

Non-Surgical Therapy and Oral Microbiota Features in Peri-Implant Complications: A Brief Narrative Review

The therapeutic discretion in cases of peri-implantitis should take into account the limits and advantages of specific therapeutic itineraries tailored according to each clinical case and each individual patient. This type of oral pathology emphasizes the complex classification and diagnostic issues coupled with the need for targeted treatments, in light of the oral peri-implant microbiota changes. This review highlights the current indications for the non-surgical treatment of peri-implantitis, describing the specific therapeutic efficacy of different approaches and discussing the more appropriate application of single non-invasive therapies The non-surgical treatment choice with antiseptics or antibiotics (single or combined, local, or systemic) for short courses should be considered on a case-by-case basis to minimize the incidence of side effects and concomitantly avoid disease progression.

Evaluation of Implant and Prosthesis Survival Rates Based on Crestal Bone Loss

A dental implant mimics the tooth and restores its function. It has flourished as a replacement of missing natural teeth that has a success rate over 90% over the years. However, this root-form implant has also been associated with some complications after its application. Crestal bone loss, one of the biggest challenges in dental implant placement, occurs around the dental implant neck within a few months post-loading. The aim of this study was to determine survival rates and to measure crestal bone changes after placement of a single crown prosthesis. Data collection was done in a private dental university setting. Data from approximately 296 cases were retrieved after analyzing 86,000 case sheets. The following parameters were evaluated based on dental records: age, sex, implant placement area, implant diameter and length, and presence or absence of exudate. Crestal bone loss was assessed radiographically. Excel tabulation and SPSS version 23 were used for data analysis. Chi-square testing was done to correlate various parameters used in this study. Incipient crestal bone loss was commonly observed. It was seen that the association between crestal bone loss and exudate was statistically significant (Chi-square, p < 0.05). Within the limits of this study, incipient crestal bone loss was observed in most dental implants irrespective of bone density, implant length, implant diameter, and implant placement area.

Short-term influence of antimicrobial photodynamic therapy as an adjuvant to mechanical debridement in reducing soft-tissue inflammation and subgingival yeasts colonization in patients with peri-implant mucositis

OBJECTIVE

The objective of this short-term follow-up study was to evaluate the influence of antimicrobial photodynamic therapy (aPDT) as an adjuvant to mechanical debridement (MD) in reducing soft-tissue inflammation and subgingival yeasts colonization (SYC) in patients with peri‑implant mucositis (PiM).

METHODS

Individuals diagnosed with PiM were included. Demographic data was collected using a questionnaire. Peri-implant plaque index (PI), bleeding index (BI), probing depth (PD), crestal bone levels and SYC were measured at baseline. Therapeutically, these individuals were divided into test and control groups. In the control-group patients underwent MD and in the test-group patients underwent MD with adjunct single session of aPDT. Clinical peri‑implant parameters and SYC were reassessed after 12-weeks. Correlation between age, gender and duration of implants with SYC and clinical peri‑implant status was assessed using logistic regression models. P < 0.05 was selected as an indicator of statistical significance.

RESULTS

The test and control-groups comprised of 24 and 23 individuals, respectively. In the test and control groups, toothbrushing twice daily was reported by 7 (29.2%) and 5 (21.7%) individuals, respectively. None of the individuals had ever used a dental floss. At baseline, there was no difference in peri‑implant PI, BI, PD and CBL in the test and control groups. At follow-up, peri‑implant PI (P < 0.01), BI (P < 0.01) and PD (P < 0.01) were significantly higher in the control compared with the test-group. At baseline, SYC in the test and control groups were 1865.3 ± 403.4 CFU/ml and 1963.7 ± 512.4 CFU/ml, respectively. At 90 days' follow-up, SYC in the test and control groups were 1472 ± 202.7 and 1538.4 ± 331.7 CFU/ml, respectively. There was no significant difference in SYC in both groups when baseline values were compared with 90 days' follow-up.

CONCLUSION

One session of aPDT after MC with adjunct aPDT is effective in reducing soft tissue inflammation but not SYC in patients with PiM.

Chloro-aluminum phthalocyanine-mediated photodynamic therapy improves peri-implant parameters and crevicular fluid cytokine levels in cigarette smokers with chronic hyperglycemia

PURPOSE

This clinical trial aimed to evaluate the effectiveness of chloroaluminum phthalocyanine-mediated photodynamic therapy (CAPC-PDT) as an adjunct to peri-implant mechanical debridement (PID) in the treatment of peri-implantitis in patients with chronic hyperglycemia and cigarette smoking.

METHODS

The selected participants with peri-implantitis were divided into two groups: Group I (n=15) included hyperglycemic patients with no history of smoking and Group II (n=15) included hyperglycemic patients with a history of smoking cigarettes. Both groups were further divided into two subgroups based on the type of therapy provided: PDT+PID and PID alone. Peri-implant bleeding on probing (PiBOP), peri-implant pocket depth (PiPD), peri-implant plaque scores (PiPS), and crestal bone loss (CBL) were assessed. Peri-implant crevicular fluid (PICF) was sampled for quantification of interleukin (IL)-1β and tumor necrosis factor-alpha (TNF-α) using an enzyme-linked immunosorbent assay. All assessments were performed at baseline and at three and six months.

RESULTS

PDT+PID showed a higher reduction in PiBOP than PID alone in hyperglycemic/non-smoking participants (p<0.01). PDT+PID and PID show a significant reduction in PiBOP in smokers only at 6 months (p<0.05), with comparable differences between PDT+PID and PID (p>0.05). PDT+PID significantly reduced PiPD hyperglycemic/smoking patients at 3 and 6 months (p<0.05), whereas PID only produced a significant reduction in PiPD at 6 months in smoking patients (p<0.05). CBL alone with PDT+PID in both smokers and non-smokers showed a statistically significant reduction at 6 months follow-up (p<0.05). IL-1β was significantly reduced in hyperglycemic/non-smoking participants at 6 months follow-up with both PDT+PID and PID alone (p<0.01). This trend was also observed in cigarette smokers, with an additional short-term reduction in IL-1β at 3 months with PDT+PID (p<0.05). Only the PDT+PID group showed a significant reduction in TNF-a among cigarette smoking patients with chronic hyperglycemia at 6 months follow-up (p<0.05) CONCLUSION: Chloroaluminum phthalocyanine-mediated PDT proved effective in improving peri-implant clinical outcomes and reducing cytokine levels in smoking patients with chronic hyperglycemia.

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).

Peri-implantitis: A bibliometric network analysis of top 100 most-cited research articles

BACKGROUND

Over the past decades, there has been an increase in research publications focusing on peri-implantitis. When facing limited healthcare resources, bibliometric analyses can guide researchers and funding parties toward areas where reallocation or more focus on research activity is warranted. The main objective of this study was to identify the trends of the top 100 cited articles on peri-implantitis research as the first study of its kind.

METHODS

A Web of Science search, using the keywords "peri-implantitis or periimplantitis" was built to create a database of the most-cited articles. Articles were ranked by citation count and screened by two independent reviewers. The bibliometric characteristics of the studies were gathered and analyzed using several bibliometric software. Author collaborations, author clusters, and keyword co-occurrence network analyses were also performed. The correlation between the citation count and the age of each article was tested.

RESULTS

The top 100 cited papers were published from 1994 to 2018 and the total citation counts ranged from 119 to 972 with 244.5 citations/paper on average. There was no correlation between the age of the articles and the citation count (p-value = 0.67). 21% of the studies consisted of prospective clinical studies. 35% of the papers focused on treatment and prevention of peri-implantitis while 65% concerned epidemiology. The top three most prolific countries were Sweden (n = 31), Germany (n = 15), and Switzerland (n = 13). We found 12 authors who had greater than five publications on the list. Also, the most published journal was Clinical Oral Implants Research.

CONCLUSION

This study provides insight into the characteristics and quality of the most highly cited peri-implantitis literature. This revealed a deficiency in terms of the number of studies on treatment strategies as well as a higher level of evidence studies among the most- impactful papers on peri-implantitis at the moment.

In Vivo Biofilm Formation on Novel PEEK, Titanium, and Zirconia Implant Abutment Materials

The formation of biofilms on the surface of dental implants and abutment materials may lead to peri-implantitis and subsequent implant failure. Recently, innovative materials such as polyether-ether-ketone (PEEK) and its modifications have been used as abutment materials. However, there is limited knowledge on microbial adhesion to PEEK materials. The aim of this in vivo study was to investigate biofilm formation on the surface of conventional (titanium and zirconia) and PEEK implant abutment materials. Split specimens of titanium, zirconia, PEEK, and modified PEEK (PEEK-BioHPP) were manufactured, mounted in individual removable acrylic upper jaw splints, and worn by 20 healthy volunteers for 24 h. The surface roughness was determined using widefield confocal microscopy. Biofilm accumulation was investigated by fluorescence microscopy and quantified by imaging software. The surface roughness of the investigated materials was <0.2 µm and showed no significant differences between the materials. Zirconia showed the lowest biofilm formation, followed by titanium, PEEK, and PEEK-BioHPP. Differences were significant (p < 0.001) between the investigated materials, except for the polyether-ether-ketones. Generally, biofilm formation was significantly higher (p < 0.05) in the posterior region of the oral cavity than in the anterior region. The results of the present study show a material-dependent susceptibility to biofilm formation. The risk of developing peri-implantitis may be reduced by a specific choice of abutment material.

Immediate loaded fixed complete dentures supported by implants in patients with a history of periodontitis: A retrospective cohort study of 2 to 7 years

STATEMENT OF PROBLEM

The outcome of implant-supported fixed complete dentures in edentulous patients with a history of periodontitis is unclear.

PURPOSE

The purpose of this retrospective clinical study was to assess the clinical outcomes of immediate loaded fixed complete dentures in individuals with a history of periodontitis and to analyze risk factors related to implant failure.

MATERIAL AND METHODS

A total of 642 implants (146 prostheses) in 119 patients were included. The follow-up period ranged from 2 to 7 years. Implant survival rates, marginal bone loss, mechanical complications, biologic complications, and patient satisfaction were evaluated. The Pearson chi-square test, independent samples t test, and multivariate generalized estimating equation were performed for statistical analysis (α=.05).

RESULTS

Eleven implants in 9 patients failed, leading to overall survival rates of 98.3% at the implant level and 92.4% at the patient level. The mean ±standard deviation marginal bone loss was 0.62 ±0.86 mm, and marginal bone loss did not differ significantly between axial and tilted implants (P>.05). Mechanical complications were detected in 55 (37.7%) definitive prostheses; biologic complications were detected in 318 (49.5%) implants. Smokers had a significantly lower survival rate than nonsmokers (odds ratio: 6.880, P=.013). Bruxers had a significantly higher incidence of mechanical complications than nonbruxers (P<.001).

CONCLUSIONS

The immediate loaded fixed complete denture supported by implants is a suitable treatment option for edentulous patients with a history of periodontitis, with high survival implant rates. Smoking is a risk factor for implant failure. Bruxism may increase the incidence of mechanical complications with implant-supported fixed complete dentures, and the overall biologic complication incidence is comparatively high.

Novel Dental Restorative Solutions for Natural Teeth and Implants

The long-term survival of restorations in the oral cavity has always been one of the most significant challenges in modern dental practice [...].

Histomorphometrical and CBCT Evaluation of Tissue Loss Progression Induced by Consecutive, Alternate Ligatures in Experimental Peri-Implantitis in a Dog Model: A Pilot Study

Objectives: Soft and hard tissue breakdown was histologically and radiologically assessed around implants with alternate, consecutively placed ligatures on the same edentulous dog hemimandible. The influence of ligatured implants (LI) on adjacent non-ligatured implants (NLI, as a possible naturally induced peri-implantitis) was also evaluated. Material and Methods: Three months after tooth extraction, five dental implants were placed in the dog hemimandible. Two months after abutment placement, ligatures were placed subsequently two months apart on alternate implants, while both intermediate implants were left without ligatures. Ligatures were kept in place during the entire experiment, and no plaque control measures were taken. Eleven months post-implantation, the animal was sacrificed. Undecalcified ground sections were cut, stained with Masson Goldner and MOVAT Pentachrome and evaluated by light microscopy. Soft and hard tissue loss was assessed using histomorphometric and CBCT parameters. Results: All NLI presented deep false peri-implant pockets on the oral aspect and pronounced vertical bone resorption on the buccal aspect. After 2, 4 and 6 months, during the breakdown period, more than 30% of the bone was lost in LI in all directions, while, despite immediate vicinity, NLI displayed less destruction. Intense inflammation, typical for induced peri-implantitis, was present, with similar intensity in LI as NLI, but in different parts of the lesions. Morphometry confirmed intense soft tissue inflammation, more bone resorption and higher amounts of infiltrated connective tissue in LI when compared with NLI. Conclusion: Within the limits of the present pilot study, the adequacy of the experimental dog model based on ligature-induced peri-implantitis was able to be successfully challenged by non-ligature models of spontaneously occurring peri-implant inflammation, while meeting the requirements for experimental designs with a very small numbers of animals. The influence of implants with severe peri-implantitis on adjacent implants resulted in less than expected tissue loss in the latter accession numbers.

What is the prevalence of peri-implantitis? A systematic review and meta-analysis

Background

Peri-implantitis is a usual finding but estimates of its prevalence fluctuate very much. This may be due to the wide variety of disease definitions. This systematic review aims to estimate the overall prevalence of peri-implantitis and the effect of different study designs, function times and use of probing depth on prevalence rate.

Methods

Following electronic and manual searches of the literature published from January 2005 to December 2021, data were extracted from the studies fitting the study criteria. Fifty-seven articles were included in this study.

Results

Prevalence of peri-implantitis was 19.53% (95% CI 12.87–26.19) at the patient-level, and 12.53% (95% CI 11.67–13.39) at the implant-level and it remains highly variable even following restriction to the clinical case definition. The use of probing depth like diagnostic criteria affected the prevalence data.

Conclusion

The results indicate that it remains essential the identification of the diagnostic markers for more accurate disease classification.

LEVELS OF SMOKING AND PERI‑IMPLANT MARGINAL BONE LOSS: A SYSTEMATIC REVIEW AND META-ANALYSIS

AIM

This systematic review and meta-analysis sought to determine if there was a significantly enhanced risk of peri‑implant marginal bone loss (MBL) due to the increased number of cigarettes smoked per day.

MATERIALS AND METHODS

Six databases, including Medline, Embase, Cochrane Library, Web of Science, Scopus, and ProQuest, were searched until February, 2021. The search terms "dental implant, oral implant, smoking, smoker, non-smoker, marginal bone loss and crestal bone loss" were used in combination to seek the articles providing data for MBL related to the smoking habit. Articles were excluded if the quantity of cigarettes smoked per day was not reported. Random-effects meta-analyses were used to pool the estimates of mean difference (MD) with 95% confidence intervals (CI).

RESULTS

Eight studies were included for qualitative and 5 for quantitative synthesis. The meta-analyses revealed higher levels of MBL in patients who smoked <10 or >10 cigarettes/day than in non-smokers (<10: (MD -0.33, 95% CI -0.69-0.03 and >10: MD -0.58, 95% CI -0.96- -0.19). There was a significant risk of MBL between patients who smoked >10 and <10 cigarettes/day (MD -0.23, 95% CI -0.47-0.01).

CONCLUSION

It seems the risk of MBL is steadily increasing as daily smoking increases.

A Retrospective Analysis of Biological Complications of Dental Implants

Methods

A retrospective analysis of patients aged ≥18 years and having dental implants placed at Dubai Health Authority in 2010. Relevant information related to systemic-, patient-, implant-, site-, surgical- and prosthesis-related factors were collected. The strength of association between the prevalence of peri-implant mucositis and peri-implantitis and each variable was measured by chi-square analysis. A binary logistic regression analysis was performed to identify possible risk factors.

Results

A total of 162 patients with 301 implant-supported restorations were included in the study. The age of the patients ranged between 19 and 72 with a mean age of 46.4 ± 11.7 years. The prevalence of peri-implant mucositis at the patient and implant levels were 44.4% and 38.2%, respectively. For peri-implantitis, the prevalence at the patient level was 5.6%, while the prevalence at the implant level was 4.0%. The binary logistic regression identified three risk factors (smoking habits, histories of treated periodontitis and lack of peri-implant maintenance) for peri-implantitis.

Conclusion

Within the limitations of this study, smoking habits, history of treated periodontitis and lack of peri-implant maintenance were significant risk factors for peri-implantitis. Early detection of these factors would ensure appropriate planning and care of patients at high risk of developing peri-implant diseases.

Clinical, Microbiological, and Biochemical Impact of the Surgical Treatment of Peri-Implantitis-A Prospective Case Series

Background: The aim of this study, a prospective case series, was to evaluate the clinical, microbiological, and biochemical impact of the surgical treatment of peri-implantitis. Methods: Thirty subjects with diagnosis of peri-implantitis were treated following a surgical protocol including access flaps, surface decontamination with ultrasonics and glycine powder air-polishing, and systemic antibiotics. Disease resolution was defined by the composite outcome including presence of probing depths (PD) ≤5 mm, absence of bleeding on probing (BoP)/suppuration, and no additional radiographic bone loss (>1 mm). Regression analysis was used to evaluate the patient-, implant-, and prosthetic-related factors possibly influencing treatment outcomes. Results: Patients were evaluated at 6 months post treatment, demonstrating statistically significant reductions in PD (2.14 ± 1.07 mm) and increase in mucosal recession (1.0 ± 0.77 mm). Plaque, BoP, and suppuration were also reduced by 40.56%, 62.22%, and 7.78%, respectively. Disease resolution was achieved in 56.67% of patients. No significant changes were detected in microbiological parameters except for a significant reduction in proportions of Parvimonas micra. Similarly, the levels of the biomarker interleukin-8 in crevicular fluid were significantly lower at 6 months. Conclusions: The proposed surgical treatment of peri-implantitis demonstrated statistically significant clinical improvements although the impact on microbiological and biochemical parameters was scarce.

The benefit of antimicrobial photodynamic therapy to mechanical debridement in the treatment of smokers with peri-implant diseases: a systematic review and meta-analysis

Antimicrobial photodynamic therapy (aPDT) has been proposed as an adjunctive treatment strategy for peri-implant diseases. This systematic review aimed to determine whether aPDT as an adjunct to mechanical debridement has an additional benefit for smokers with peri-implant diseases. Randomized controlled trials (RCTs), which evaluated the clinical outcomes of mechanical debridement alone versus mechanical debridement + aPDT among smokers, were considered eligible to be included. The primary outcome was bleeding on probing (BOP) and secondary outcomes included probing depth (PD), plaque index (PI), and crestal bone loss (CBL). Meta-analyses using a random-effects model were conducted to calculate the mean difference (MD) with a 95% confidence interval (CI). The quality of evidence was assessed according to Grading of Recommendations Assessment, Development and Evaluation (GRADE). A total of four RCTs (188 participants) were included. The aPDT group showed significantly improved PD (MD =  - 1.26, 95% CI =  - 2.19 to - 0.32, p = 0.008) and PI (MD =  - 10.6%, 95% CI =  - 14.46 to - 6.74%, p = 0.0001) compared with mechanical debridement group at 3-month follow-up. No significant difference in bleeding on probing (BOP) was observed at 3-month follow-up (MD =  - 0.60%, 95% CI =  - 2.36 to 1.16%, p = 0.50). The subgroup analyses on photosensitizers demonstrated significant differences between the two groups on PD (MD =  - 1.23, 95% CI =  - 2.41 to - 0.05, p = 0.04) and PI (MD =  - 12.33, 95% CI =  - 14.74 to - 9.92, p < 0.00001) by the use of methylene blue (MB). Within the limitation of this study, compared with mechanical debridement alone, combined use of aPDT was more effective in reducing PD and PI in smokers at 3-month follow-up. MB was a predictable photosensitizer for aPDT. However, the findings should be interpreted with caution due to the limited number of included studies, methodological deficiencies, and heterogeneity between studies.

Fermented lingonberry juice's effects on active MMP-8 (aMMP-8), bleeding on probing (BOP), and visible plaque index (VPI) in dental implants-A clinical pilot mouthwash study

OBJECTIVES

We aimed to study the effects of fermented lingonberry juice (FLJ) as a mouthwash on the levels of active matrix metalloproteinase-8 (aMMP-8) in peri-implant sulcular fluid (PISF), bleeding on probing (BOP), and visible plaque index (VPI). We hypothesized that FLJ rinsing could reduce inflammation (aMMP-8 and BOP) and microbial load (VPI) in the oral cavity, especially around dental implants.

MATERIALS AND METHODS

A clinical pilot study was performed using FLJ as a mouthwash. The inclusion criteria were at least one dental implant in the anterior or posterior areas with a screw-retained crown. Ten participants used 10 ml of mouthwash twice a day for 15 days, and 10 participants served as the control group. Point-of-care tests (POCTs) were used to measure aMMP-8 levels in the PISF, and BOP and VPI were recorded at the beginning of the trial and after 15 and 30 days.

RESULTS

The FLJ mouthwash had a reductive effect on aMMP-8, VPI, and BOP in the mouthwash group; however, there was no significant difference compared to the control group. The difference in VPI and BOP levels between the groups diminished after the lingonberry regimen ended. The decrease in aMMP-8 levels appeared to continue even after discontinuation of the mouthwash regimen.

CONCLUSION

The reduction in the amount of plaque, aMMP-8, and BOP by FLJ was promising and continuous considering the relatively short study period and sample size. FLJ is a natural and safe supplement for oral and dental implant home care. Further studies are required to verify these promising results.

The Influence of Keratinized Mucosa on the Nonsurgical Therapeutic Treatment of Peri-Implantitis

OBJECTIVE

The main objective of this study aimed to evaluate the response to treatment in implants with peri-implantitis regarding the presence or absence of keratinized mucosa.

MATERIALS AND METHODS

One hundred implants with peri-implantitis were treated non-surgically at the Prosthodontics and Occlusion Teaching Unit of the University of Valencia. Records were registered at day zero (recession, bleeding on probing, suppuration, probing depth, bone loss and plaque index), at 1, 3 and 6 months.

RESULTS

In both groups, a slight increase in recession and disappearance of suppuration took place, and no bone loss was observed during the following 6 months. However, after an initial reduction, probing depth, bleeding on probing and plaque index increased again in the group without keratinized mucosa (KM).

CONCLUSIONS

Implants with KM presented better results after non-surgical treatment as well as in their medium-term evolution, although it would be advisable to increase the number of samples in order to achieve greater scientific evidence and standardization in the treatment protocol.

CLINICAL RELEVANCE

The role of keratinized mucosa in the development of peri-implantitis has been mentioned in many publications, but less has been emphasized regarding its influence on the success of the treatment of this pathology. The presence of keratinized mucosa has been found to play a key role in the evolution of the non-surgical treatment of peri-implantitis. The amount of keratinized mucosa should be considered in the treatment of peri-implantitis, as well as when planning connective tissue grafts accompanying the decontamination of implants in the absence of keratinized mucosa.

Retrospective Study of the Association between Peri-Implantitis and Keratinized Mucosa

1. Background: Peri-implantitis affects a high percentage of patients treated with dental implants. Among the risk factors that can cause this pathology, limited evidence exists regarding the absence of keratinized mucosa. The main objective of this study was to compare the amount of keratinized mucosa around healthy implants versus implants in patients with peri-implantitis, in order to analyze its influence on esthetics and the development of this pathology, and to study the possible influence of keratinized mucosa on various clinical parameters. 2. Methods: A retrospective case-control study was carried out in which 203 implants were evaluated, 103 of which presented a healthy peri-implant state, versus 100 which had peri-implantitis. The following elements were recorded: keratinized mucosa, recession, plaque index, bleeding, suppuration, probing depth, and bone level. 3. Results: Keratinized mucosa was present in 51% of the peri-implantitis group versus 97.1% of the healthy implants. In implants without keratinized mucosa, both recession and plaque index, bleeding on probing (96.2%), suppuration (57.7%), mean probing depth and bone level were higher. Implants without keratinized mucosa presented worse esthetics. 4. Conclusions: Absence of Keratinized mucosa around dental implants seems to be associated with the appearance of peri-implantitis modifying certain clinical parameters: there is a greater probability of recession, bleeding, suppuration, deficient hygiene, greater probing depth and greater bone loss in implants without keratinized mucosa.

Association between IL-1A, IL-1B and IL-1RN Polymorphisms and Peri-Implantitis: A Systematic Review and Meta-Analysis

Recent studies report that individuals with polymorphisms in the genes that encode for interleukin (IL)-1α and IL-1β (IL-1A and IL1B, respectively) and for IL-1 receptor antagonist (IL-1RN) may be more susceptible in developing peri-implantitis. Therefore, the current systematic review evaluates what is reported about the role of genetics, more specifically of single nucleotide polymorphisms (SNP) on IL-1 and variable number of tandem repeats (VNTR) on IL-1RN, in the development of peri-implantitis. This systematic review was carried out by screening PubMed, B-on, Cochrane and Scopus databases, for articles English, Spanish, and Portuguese, with no limit regarding the publication year. Eight articles were selected for systematic review and four for meta-analytic syntheses. Our results show that although there is a lack of consensus in the literature, there seems to be an association between IL-1A, IL-1B, and IL-1RN polymorphisms with peri-implantitis. The results of the meta-analysis showed that patients who have the polymorphic allele at position +3954 of the IL-1B gene have on average almost twice the risk of developing peri-implantitis (odds ratio = 1.986, 95% confidence interval).