A comprehensive and critical review of dental implant prognosis in periodontally compromised partially edentulous patients

Peri-implantitis as the consequence of errors in implant therapy

Peri-implantitis is a plaque-associated pathologic condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant mucosa and subsequent progressive loss of supporting bone. It is a highly prevalent disease, as extensively estimated by large-population, cross-sectional studies. As peri-implant diseases represent opportunistic infections, it is reasonable to assume that nonideal conditions, local and/or general, may favor the progression of peri-implant inflammation. Some of these conditions could be a result of poor planning and/or inadequate execution of any step of the entire process treatment. This article describes the major possible factors in implant therapy that may lead to peri-implantitis. For some of these (ie, inappropriate patient selection, insufficient periodontal therapy, lack of diagnosis and management of peri-implant mucositis, erratic supportive peri-implant/periodontal therapy) there is a good level of evidence, whereas for others (ie, wrong implant placement, poor postoperative care, inadequate prosthetic reconstruction, lack of assessment and management of peri-implant soft-tissue deficiencies) there is little scientific evidence. More research is therefore needed to clearly identify the errors and/or complications possibly leading to peri-implantitis, particularly over the long term.

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.

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.

Molecular Biomarkers in Peri-Implant Health and Disease: A Cross-Sectional Pilot Study

Background: The aim of this feasibility study was to investigate the concentration level of CCL-20/MIP-3α, BAFF/BLyS, IL-23, RANKL, and Osteoprotegerin in the Peri-Implant Crevicular Fluid (PICF), from patients diagnosed with peri-implant mucositis and peri-implantitis, and to compare them with PICF from patients with healthy implants. Methods: Participants with at least one dental implant with healthy peri-implant tissues, peri-implant mucositis, or peri-implantitis were included. PICF was collected using paper strips from healthy and diseased peri-implant sites (n = 19). Biomarker levels were analyzed using a custom Multiplex ELISA Assay Kit. Results: In comparison to peri-implant health, the peri-implant mucositis group showed an increased concentration of CCL-20 MIP-3α, BAFF/BLyS, IL-23, RANKL, and Osteoprotegerin. The peri-implantitis group had the lowest median concentration of Osteoprotegerin (1963 ng/mL); this group had a similar concentration of RANKL (640.84 ng/mL) when compared to the peri-implant health group. BAFF/BLyS (17.06 ng/mL) showed the highest concentration in the peri-implantitis group. Conclusions: This feasibility study suggests that IL-23 and RANKL may help to elucidate the pathogenesis during the conversion from peri-implant health to peri-implantitis. Further research is required in BAFF/BLyS for the early diagnosis of peri-implantitis.

Asperuloside Prevents Peri-Implantitis via Suppression of NF-κB and ERK1/2 on Rats

Peri-implantitis is characterized by inflammatory cell infiltration and hyperactivation of the osteoclasts surrounding dental implants which can result in bone resorption and ultimately implant failure. Therefore, coordinating the activity of inflammatory response and bone-resorbing osteoclasts is crucial for the prevention of peri-implantitis. Asperuloside (ASP), an iridoid glycoside, has significant anti-inflammatory activities, suggesting the great potential in attenuating peri-implantitis bone resorption. A ligature-induced peri-implantitis model in the maxilla of rats was established, and the effects of ASP on preventing peri-implantitis were evaluated after four weeks of ligation using micro-CT and histological staining. RT-PCR, western blotting, tartrate-resistant acid phosphatase (TRAP), and immunofluorescent staining were conducted on osteoclasts to confirm the mechanisms of ASP on osteoclastogenesis. The results show that ASP could lead to attenuation of alveolar bone resorption in peri-implantitis by inhibiting osteoclast formation and decreasing pro-inflammatory cytokine levels in vivo. Furthermore, ASP could inhibit osteoclastogenesis by downregulating expression levels of transcription factors nuclear factor of activated T-cell (NFATc1) via restraining the activations of nuclear factor kappa beta (NF-κB) and the phosphorylation of extracellular signal-related kinase 1/2 (ERK1/2). In conclusion, ASP could significantly attenuate bone resorption in peri-implantitis via inhibition of osteoclastogenesis by suppressing NF-κB and ERK1/2 signaling pathways activations.

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.

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).

Peri-implant crevicular fluid SIRT1 levels decrease in patients with peri-implant inflammatory: A prospective observational study

BACKGROUND

A dental Implant is a prosthetic device made of alloplastic materials implanted into the bone to provide retention and support for a dental prosthesis. Sirtuin1 (SIRT1) molecule, a nicotinamide adenine dinucleotide (NAD)-dependent histone deacetylase, regulates a variety of physiological and pathological processes, including oxidative stress, metabolism, cell proliferation, cell differentiation, inflammatory, and apoptosis. We explored whether the expression of SIRT1 correlates in patients receiving implants with peri-implant mucositis (PIM) and peri-implantitis (PI) in comparison to patients with healthy peri-implant area (PIH).

METHODS

A number of 198 patients with dentition defects were enrolled in the study after their implants were functional for at least 6 months. All 198 subjects were divided into 3 groups: 1) control patients with PIH healthy implants; 2) patients with PIM mucositis; and 3) patients with PI implantitis. To distinguish these three groups, peri-implant crevicular fluid (PICF) was collected by inserting a sterile paper strip into the gap around the implant and the levels of SIRT1 and cytokines were measured by the enzyme linked immunosorbent assay (ELISA). Demographic and clinical data included age, sex, Body Mass Index (BMI), probing depth (PD), plaque index (PLI), bleeding on probing (BOP), oral health impact profile (OHIP-14), history of periodontitis and the use time of implants.

RESULTS

The PD, PLI, OHIP-14 evaluation scores in patients with periodontitis of PIM mucositis and PI implantitis were all significantly higher than in patients with PIH healthy implants. Overall, the SIRT1 levels in PICF of the PIM and PI patients were significantly lower than of the PIH patients. In comparison with PIM patients, SIRT1 levels of the PI patients were remarkably lower than the PIH patients. Pearson's analysis showed that SIRT1 levels were negatively correlated with levels of interleukin (IL)-6, C-reactive protein (CRP) and IL-1β in patients with PIM and PI. We suggest that SIRT1 levels could serve as a potential diagnostic biomarker of PI or PIM. The PICF levels of SIRT1, CRP, IL-6, IL-1β and the history of periodontitis were the risk factors for patients with peri-implant inflammatory process.

CONCLUSION

The measurement of SIRT1 expression in PICF may serve as a biomarker for the ongoing inflammatory process in patients with dental implants. The low SIRT1 levels correlated with PI implantitis and PIM mucositis as well as the elevated levels of pro-inflammatory cytokines (CRP, IL-6 and IL-1β).

Comparison of peri-implant marginal bone level changes between tapered and straight implant designs: 5-year follow-up results

PURPOSE

The aim of this study was to compare straight and tapered implant designs in terms of marginal bone loss, the modified plaque index (mPI), and the modified bleeding index (mBI) for 5 years after functional loading.

METHODS

Twelve patients were recruited. Two types of implants were placed adjacent to each other: 1 straight implant and 1 tapered implant. Marginal bone loss, mPI, and mBI were measured every year for 5 years after loading.

RESULTS

The straight implants showed 0.2±0.4 mm of marginal bone loss at 5 years after loading, while the tapered implants showed 0.2±0.3 mm of marginal bone loss; this difference was not statistically significant (P=0.833). Our analysis also showed no statistically significant differences in mPI (straight implants: 0.3±0.3 vs. tapered implants: 0.2±0.3; P=0.414) or in mBI (straight implants: 0.3±0.4 vs. tapered implants: 0.2±0.3; P=0.317) at 5 years after prosthesis delivery.

CONCLUSIONS

Straight and tapered implants showed no significant differences with respect to marginal bone loss, mPI, and mBI for 5 years after loading.

Association between Interleukin-1 Polymorphisms and Susceptibility to Dental Peri-Implant Disease: A Meta-Analysis

Background and objective: Interleukins (ILs), as important biochemical mediators, control the host response to inflammation and are associated with bone resorption. In the present meta-analysis, we investigated the association between IL−1 polymorphisms and susceptibility to dental peri-implant disease (PID). Materials and methods: We searched Web of Science, Cochrane Library, Scopus, and PubMed/Medline databases for studies published until 9 September2021, without any restrictions. We calculated the crude OR and 95% confidence intervals (CI) to estimate the associations between IL−1 polymorphisms and PID risk in the five genetic models. We further performed the subgroup analysis, sensitivity analysis, meta-regression, trial sequential analysis, and calculated the publication bias. Results: Out of 212 retrieved records, sixteen articles were used in the meta-analysis. There was no association between IL−1A (–889), IL−1B (−511), IL−1B (+3953), and IL−1RN (VNTR) polymorphisms and the risk of dental PIDs, but there was an increased risk of IL−1B (+3954) in the patients with PIDs. In addition, an association of the composite genotype of IL−1A (−889)/IL−1B (+3953) was observed with the risk of PIDs, but not for the composite genotype of IL−1A (−889)/IL−1B (+3954). The publication year, the ethnicity, sample size, and the outcome were significantly influenced pooled estimates of some genetic models. Trial sequential analysis showed the lack of sufficient sample sizes in the studies. Conclusions: Among IL−1 polymorphisms evaluated in the meta-analysis, the composite genotype of IL−1A (−889)/IL−1B (+3953) and IL−1B (+3954) were the only polymorphisms associated with the risk of PID. The T allele and CT genotype of IL−1B (+3954) polymorphism were also associated with an elevated risk of PID.

Peri-implant health after supportive mucositis therapy is associated with increased levels of FGF-2

This study aimed to analyze Fibroblast Growth Factor-2 (FGF-2) levels in the peri-implant crevicular fluid throughout supportive mucositis therapy. Twenty-six participants with Branemark protocol prosthesis were divided into two groups: the control group, characterized by healthy peri-implants, and the mucositis group, presenting a diagnosis of peri-implant mucositis. All participants underwent clinical examination, radiographic analysis, prosthesis removal, and non-invasive peri-implant therapy (mechanical debridement associated with chlorhexidine 0.12%) during a period of 36 days divided into three intervals. Peri-implant crevicular fluid samples were collected at each interval in order to analyze FGF-2 levels by immuno-enzymatic assay. The control and mucositis groups showed difference in keratinized mucosa. The smaller the range of keratinized mucosa the higher susceptibility of peri-implant mucositis. Throughout the treatment intervals, participants were diagnosed in different groups indicating whether or not the non-invasive therapy was able to treat peri-implant mucositis. There was a significant difference of FGF-2 levels between groups, with the higher FGF-2 levels in the control group (p=0.01). After supportive therapy, the mucositis group showed significantly increased FGF-2 levels (p<0.01) compared to initial levels. After 36 days of supportive therapy, there was a reduction of peri-implant mucositis from 70% to 23%. Clinical and laboratory outcomes showed a clear correlation since FGF-2 levels increased after 36 days. It was concluded that the therapy protocol was effective and promoted a regenerative reaction and FGF-2 can be considered a future target for peri-implant mucositis understanding.

Impact of tooth loss due to periodontal disease on the prognosis of rehabilitation

When periodontal disease is diagnosed, it is difficult to predict the clinical response of treatment of a tooth over time because the result of treatment is affected by several factors and will depend on the maintenance and support of periodontal treatment. Rehabilitation with removable dental prostheses, fixed prostheses, and dental implants makes it possible to restore the function and esthetics of patients with tooth loss due to periodontal disease. The predictive factors of tooth loss in periodontitis patients should be assessed by dentists to inform their clinical decision-making during dental treatment planning. This will provide detailed individualized information and level of risk of patients considered suitable for dental rehabilitation. Therefore, the aim of this article was to review the subject of "Impact of tooth loss due to periodontal disease on the prognosis of rehabilitation" and the effect of fixed, removable, and implant-supported prostheses in periodontal patients.

Generalized periodontitis treated with periodontal, orthodontic, and prosthodontic therapy: A case report

BACKGROUND

Generalized periodontitis is a severe periodontal disease characterized by rapid periodontal destruction in healthy persons. This case report describes the treatment of a severe crowding, large overjet, and occlusal collapse due to the loss of anterior guidance with generalized periodontitis.

CASE SUMMARY

A 35-year-old female patient with a chief complaint of crowding and maxillary protrusion was diagnosed with generalized periodontitis by clinical and radiographic examinations. To improve crowding and overjet, orthodontic treatment was performed after basic periodontal therapy. Severely damaged upper right lateral incisor and left canine were extracted, and lower right first premolar and left second premolar were also removed to treat severe crowding. After orthodontic treatment, periodontal flap surgery for upper left molars and guided tissue regeneration for the lower left second molar was performed. Then, a dental implant was inserted in the upper left canine legion. The esthetics of the maxillary anterior tooth was improved by prosthetic restorations. The treatment result showed a well-improved occlusion with proper anterior guidance and healthy periodontal tissue after a retention period of 10 years.

CONCLUSION

Periodontal, orthodontic, and prosthodontic treatments are extremely useful to improve function and stable periodontal tissue for generalized periodontitis.

A Cross-Sectional Analysis on Factors Associated With Peri-Implant Pathologies at the Implant Level

Pathologies in peri-implant tissues are common and may disturb long-term implant supported rehabilitation. We aimed to evaluate the occurrence of such peri-implant diseases and their associated factors in this study. Peri-implantitis and mucositis were diagnosed based on clinical and radiological findings. Statistical analysis was performed with the X2 and logistic regression. Peri-implant mucositis and peri-implantitis were observed in 43.4% and 13.8% of patients with implants evaluated, respectively. Univariate analysis found associations with systemic changes (P = .016; yes), medication use (P = .010; yes), implant location (P < .0001; upper jaw), implant region (P = .008; posterior), previous augmentation procedure (P = .023; yes), time of prostheses use (P < .0001; >2 years), keratinized mucosa (P < .0001; absence); and gingival bleeding index (P = .005; >30%). In the multiple analysis, independent predictors were: >2 years of prostheses use (P < .0001; PR = 1.720), upper jaw location (P < .0001; PR = 1.421), gingival bleeding index >30% (P = .001; PR = 1.496), and use of medication (P < .0001; PR = 1.261). The frequency of peri-implant pathologies is high (approximately 57.2%) with several aspects of the occurrence being related to the patients' prosthesis. Prostheses type and the complexity of rehabilitation are worth highlighting. Factors include the location of the dental implant, gingival bleeding index, patient's use of medication(s), and the time of prostheses use.

Evaluation of peri-implant tissues condition after 10-15 years of loading in treated chronic periodontitis patients attending a private practice setting: A retrospective study

OBJECTIVES

To retrospectively evaluate the conditions of the peri-implant tissues in treated patients with chronic periodontitis (CP) and in patients without chronic periodontitis (noCP).

MATERIALS AND METHODS

A chart review was used to evaluate 267 implants, 134 placed in 42 CP treated patients and 133 placed in 46 noCP patients. The primary outcome was to evaluate the condition of the peri-implant tissues (health, peri-mucositis, and peri-implantitis). The secondary outcome was to evaluate the possible association of some variables, such as, Plaque Index (PI), Bleeding Index (BI), probing pocket depth (PD), bleeding on probing (BoP), bone level (BL), loading time, type of implant placement and loading protocol, type of prosthesis, type of bone, implant manufacturer, and implant diameter and length, with the implant health condition.

RESULTS

The analysis of patient files revealed that after 10-15 years of loading (mean loading time 13.4 ± 2.07 years), six noCP patients (13%) experienced implant loss with a total of nine implants (6.7%) lost. The remaining 124 implants were classified: 54 (43.5%) as healthy, 45 (36.3%) with peri-implant mucositis, and 25 (20.2%) with peri-implantitis. Twelve CP subjects (28.5%) experienced implant loss with a total of 19 implants (14.1%) lost. The remaining 115 implants were classified: 34 (29.5%) as healthy, 40 (34.7%) with peri-implant mucositis and 41 (35.6%) with peri-implantitis. Compared with noCP subjects, only treated CP subjects with recurrent periodontal disease (RPD) showed differences statistically significant (p < .05).

CONCLUSIONS

After 10-15 years of loading, in CP patients treated in a private practice setting, most implants (70.1%) were classified with some type of peri-implant inflammation. In patients with RPD, a higher tendency for implant loss and peri-implant biologic complications was found.

Interleukin-10-Producing B Cells Help Suppress Ovariectomy-Mediated Osteoporosis

Osteoporosis is prevalent in elderly women and it may cause dental implant failure. In particular, estrogen deficiency in postmenopausal women leads to higher rates of osteoporosis prevalence. Immune cell-mediated effects involving the development of osteoporosis have been studied previously; however, the role of IL-10-producing regulatory B (B10) cells in osteoporosis is largely unclear. Here, we examined the role of B10 cells in osteoporosis. C57BL/6 mice were subjected to ovariectomy (OVX). Fifteen weeks after OVX surgery, the first molar of the right maxillary was extracted, and twenty-four weeks after OVX surgery, serous progression of osteoporosis was observed in the alveolar bone. Moreover, the proportion of CD19⁺CD5⁺CD1d^high regulatory B cells, B10, and CD4⁺CD25⁺FoxP3⁺ regulatory T cells from the spleen of OVX mice decreased during the progression of osteoporosis, compared to controls. In contrast to regulatory cells, IL-17-producing Th (Th17) cell levels were increased in OVX mice. Adoptive transfer of B10 cells to OVX mice led to a decrease in Th17 cell abundance and inhibited the development of osteoporosis in the alveolar bone from OVX mice. Thus, our results suggest that B10 cells may help suppress osteoporosis development.

Magneto-Rheological Fluid Assisted Abrasive Nanofinishing of β-Phase Ti-Nb-Ta-Zr Alloy: Parametric Appraisal and Corrosion Analysis

The present work explores the potential of magneto-rheological fluid assisted abrasive finishing (MRF-AF) for obtaining precise surface topography of an in-house developed β-phase Ti-Nb-Ta-Zr (TNTZ) alloy for orthopedic applications. Investigations have been made to study the influence of the concentration of carbonyl iron particles (CIP), rotational speed (Nt), and working gap (Gp) in response to material removal (MR) and surface roughness (Ra) of the finished sample using a design of experimental technique. Further, the corrosion performance of the finished samples has also been analyzed through simulated body fluid (SBF) testing. It has been found that the selected input process parameters significantly influenced the observed MR and Ra values at 95% confidence level. Apart from this, it has been found that Gp and Nt exhibited the maximum contribution in the optimized values of the MR and Ra, respectively. Further, the corrosion analysis of the finished samples specified that the resistance against corrosion is a direct function of the surface finish. The morphological analysis of the corroded morphologies indicated that the rough sites of the implant surface have provided the nuclei for corrosion mechanics that ultimately resulted in the shredding of the appetite layer. Overall results highlighted that the MRF-AF is a potential technique for obtaining nano-scale finishing of the high-strength β-phase Ti-Nb-Ta-Zr alloy.

Treatment of Grade III furcation involvement in upper molars: Case Series with 2-16-year follow-up

Frequently, the clinicians are addressed to decide between the preservation of Grade III furcation molar and the implant replacement, due to the increased access among the population to this therapy over the years and high success rate of the osseointegrated implants. This case series presents clinical and radiographic data collected from 10 patients who underwent 13 root amputations for the treatment of degree Grade III furcation in maxillary molars with follow-up until 16 years. The results showed improvements in probing depth, bleeding on probing, and radiographic aspects. The follow-up time indicates that root amputation is an effective long-term treatment solution, especially when the patient's local, systemic, or financial conditions make it difficult or impossible to implant placement.

Risk Factors related to Late Failure of Dental Implant-A Systematic Review of Recent Studies

Resolving late failure of dental implant is difficult and costly; however, only few reviews have addressed the risk factors associated with late failure of dental implant. The aim of this literature review was to summarize the influences of different potential risk factors on the incidence of late dental implant failure. The protocol of this systematic review was prepared and implemented based on the PRISMA (Preferred reporting items for systematic reviews and meta-analyses) guideline. In December 2018, studies published within the previous 10 years on late dental implant failure were selected by fulfilling the eligibility criteria and the risk factors identified in qualified studies were extracted by using a predefined extraction template. Fourteen eligible studies were assessed. The common risk factors for late failure were divided into three groups according to whether they were related to (1) the patient history (radiation therapy, periodontitis, bruxism and early implant failure), (2) clinical parameters (posterior implant location and bone grade 4) or (3) decisions made by the clinician (low initial stability, more than one implant placed during surgery, inflammation at the surgical site during the first year or using an overdenture with conus-type connection). Clinicians should be cautions throughout the treatment process of dental implant—from the initial examination to the treatment planning, surgical operation and prosthesis selection—in order to minimize the risk of late failure of dental implant.

Peri-implantitis and Severity Level

Objectives  Different diagnostic criteria were used for diagnosis of peri-implant diseases. The aim of this cross-sectional study was to explore prevalence of peri-implant diseases and subclassify peri-implantitis based on different levels of radiographic and clinical findings.

Materials and Methods  Two hundred patients having 655 dental implants were included in this study. In addition to clinical measurements, standard long-cone parallel technique was used to evaluate marginal bone level around implants. Following diagnosis of peri-implant diseases, peri-implantitis was further subclassified using a severity leveling in terms of marginal bone level and probing depth.

Results  Mean age of 200 subjects was 52.8 ± 12.2 years and 63% were females. In total, bleeding on probing was present in 93% and suppuration in 27% of implants. On subject basis, 2.5% were diagnosed as healthy, 28% with peri-implant mucositis (PM), and 69.5% with peri-implantitis, whereas on implant basis, 3.6% were healthy, 36% presented PM, and 60.4% peri-implantitis. Furthermore, when severity leveling was applied, peri-implantitis prevalence changed markedly and ranged from 14.5 to 31.0% at the subject level and from 10.0 to 22.0% at the implant level. Subgingival restoration margins were observed in 70.6% of patients for implants with PM and in 44% patients for implants with peri-implantitis. Most of the implants with peri-implantitis were with platform match (71.5%).

Conclusions  Applying different thresholds to the peri-implantitis definition yielded different prevalence rates ranging from 10 to 31%. As no established diagnostic criteria are being used today, results from clinical studies may not reflect the true disease prevalence.

Evaluation of peri-implant marginal tissues around tissue-level and bone-level implants in patients with a history of chronic periodontitis

OBJECTIVE

To evaluate clinical and radiographic characteristics in peri-implant marginal tissues in patients with a history of chronic periodontitis, rehabilitated using tissue-level or bone-level implants.

MATERIAL AND METHODS

Using a split-mouth design, 20 patients with a history of chronic periodontitis were selected and received two different implants, tissue-level group (n = 20) and the bone-level group (n = 20). Peri-implant probing depth, relative peri-implant mucosal margin position, relative peri-implant clinical attachment level, peri-implant plaque index and peri-implant bleeding on probing were evaluated at prosthesis installation, 1, 3, 6, 12 and 24 months after implant loading. Radiographic marginal bone level was evaluated at implant insertion, prosthesis installation, 6 and 24 months after implant loading.

RESULTS

The mean difference of peri-implant marginal bone resorption from implant installation to 24 months in function was 0.75 ± 1.12 mm for the tissue-level group and 0.70 ± 0.72 mm for the bone-level group. No statistically significant difference was found between groups at all assessment periods for clinical and radiographic peri-implant evaluation.

CONCLUSION

Under a rigid supportive therapy, both approaches performed likewise regarding clinical and radiographic parameters for rehabilitation of patients with a history of chronic periodontitis.

Transitioning a patient with failing anterior dentition and pre-existing posterior implant-supported fixed restorations using a staged approach

This clinical report describes a staged approach using a removable partial denture (RPD) and a transitional implant-supported overdenture as interim prostheses in treating a failing anterior dentition with posterior implant-supported fixed dental prostheses (FPD), until the time a full-arch fixed implant-supported prosthesis may be inserted. The RPD replaced the anterior teeth following their extraction and during implant osseointegration. The implant-supported overdenture rehabilitated the arch during the fabrication phase of the definitive restoration.

Peri-implant alveolar bone resorption in an innovative peri-implantitis murine model: Effect of implant surface and onset of infection

PURPOSE

To compare the difference in alveolar bone resorption around implants after immediate placement in a bacterial induced experimental periimplantitis murine model. The various conditions that were examined were: Effect of implant surface characteristics and the onset of the induced infection.

MATERIALS AND METHODS

Screw-shaped titanium implants, smooth-surface or sand-blasted large-grit acid-etched (SLA) coated, were inserted immediately after extraction of the first upper left molar, in 90 5-6-week-old BALB/c mice. The mice were infected with Porphyromonas gingivalis and Fusobacterium nucleatum 21 (early infection) or 42 days (delayed infection) after implantation. Six weeks post infection, bone volume around inserted implants was measured using micro-CT, and was compared to alveolar bone level around teeth. Histological analysis was also performed.

RESULTS

The level of bone loss was significantly higher around the implants compared to the teeth, for smooth surface implants the bone loss was higher than of the SLA surface in both control and infected groups with no statistical significance. The survival rate of the implants in immediate infection was 75% compared of the 100% survival of the delayed infection and control mice. There is no significant difference between the early and the delayed infection in alveolar bone loss level around the implants.

CONCLUSIONS

This model can assist in studying the differences in alveolar bone resorption in different implants and their effect on the development of the disease.

Repeatedly Applied Peptide Film Kills Bacteria on Dental Implants

The rising use of titanium dental implants has increased the prevalence of peri-implant disease that shortens their useful life. A growing view of peri-implant disease suggests that plaque accumulation and microbiome dysbiogenesis trigger a host immune inflammatory response that destroys soft and hard tissues supporting the implant. The incidence of peri-implant disease is difficult to estimate, but with over 3 million implants placed in the USA alone, and the market growing by 500,000 implants/year, such extensive use demands additional interceptive approaches. We report a water-based, nonsur-gical approach to address peri-implant disease using a bifunctional peptide film, which can be applied during initial implant placement and later reapplied to existing implants to reduce bacterial growth. Bifunctional peptides are based upon a titanium binding peptide (TiBP) optimally linked by a spacer peptide to an antimicrobial peptide (AMP). We show herein that dental implant surfaces covered with a bifunctional peptide film kill bacteria. Further, using a simple protocol for cleaning implant surfaces fouled by bacteria, the surface can be effectively recoated with TiBP-AMP to regain an antimicrobial state. Fouling, cleansing, and rebinding was confirmed for up to four cycles with minimal loss of binding efficacy. After fouling, rebinding with a water-based peptide film extends control over the oral microbiome composition, providing a novel nonsurgical treatment for dental implants.

Effect of dental implant surface roughness in patients with a history of periodontal disease: a systematic review and meta-analysis

BACKGROUND

To review the literature on the effect of dental implant surface roughness in patients with a history of periodontal disease. The present review addresses the following focus question: Is there a difference for implant survival, mean marginal bone loss, and the incidence of bleeding on probing in periodontally compromised patients receiving a machined dental implant or rough surface dental implant?

METHODS

Electronic and manual literature searches were conducted on PubMed/MEDLINE and the Cochrane Library on studies published until May 2018 to collect information about the effect of machined, moderately rough, and rough dental implant surfaces in patients with a history of periodontal disease. The outcome variables implant survival, mean marginal bone level, and the incidence of peri-implantitis and bleeding on probing were evaluated. Meta-analysis was performed to obtain an accurate estimation of the overall, cumulative results.

RESULTS

Out of 2411 articles, six studies were included in this systematic review. The meta-analysis of the implant survival and implant mean marginal bone loss revealed a risk ratio of 2.92 (CI 95% 0.45, 18.86) for implant failure and a total mean difference of - 0.09 (CI 95% - 0.31, 0.14) for implant mean marginal bone loss measured in a total group of 215 implants, both not statistically significant.

CONCLUSIONS

Due to lack of long-term data (> 5 years), the heterogeneity and variability in study designs and lack of reporting on confounding factors, definitive conclusions on differences in implant survival, and mean marginal bone loss between machined and moderate rough implants in periodontally compromised patients cannot be drawn. Future well-designed long-term randomized controlled trials are necessary to reveal that machined surfaces are superior to moderately rough and rough surfaces in patients with a history of periodontal disease.

[A review of peri-implant microbiology]

Dental implants represent the majority of treatment strategies used to replace missing teeth. However, peri-implant diseases caused by disturbance in peri-implant microbiological balance are among the reasons for implant failure. Since the 1980s, peri-implant microorganisms have been a hot research topic in dental microbiology. The bacterial ecology between the disease and health largely differs, which directly or indirectly increases the risk of peri-implant diseases. Accordingly, the determination of the 'core microbiome' of peri-implantitis and peri-implant mucositis is a key point of recent research.

Prevalence of peri-implant disease and risk indicators in a Japanese population with at least 3 years in function-A multicentre retrospective study

OBJECTIVES

The aim of this study was to evaluate the prevalence of peri-implant disease and analyze risk indicators in Japanese subjects with ≥3 years of implant function.

MATERIAL AND METHODS

Five hundred and forty-three subjects treated with 1,613 implants were evaluated. Information was collected about the patients' physical and dental history, as well as implant details. Peri-implant evaluation included probing depth, bleeding on probing (BoP), suppuration (Sup), and keratinized tissue width. Bone loss was calculated from intra-oral radiographs taken after 1 year and more than 3 years of function. Implants were classified into three groups: healthy, peri-implant mucositis (BoP without bone loss), and peri-implantitis (BoP and/or Sup with bone loss >1 mm). These data were analyzed by multivariable multinomial logistic regression.

RESULTS

The prevalence of peri-implant mucositis and peri-implantitis at the subject level was 23.9% and 15.8%, respectively. An association was found between peri-implant mucositis and plaque control record (PCR) >20% and keratinized tissue width <2 mm. Peri-implantitis was associated with PCR >20%, smoking, insertion in the maxilla, and keratinized tissue width <2 mm.

CONCLUSIONS

Within the limitations of this study, the prevalence of peri-implant diseases was elucidated in a Japanese population. Peri-implant mucositis was associated with poor oral hygiene and less keratinized tissue. Poor oral hygiene, smoking, insertion in the maxilla, and less keratinized tissue were risk indicators for peri-implantitis.

Assessment of Dental Implants with Modified Calcium-Phosphate Surface in a Multicenter, Prospective, Non-Interventional Study: Results up to 50 Months of Follow-Up

Prescription of implant treatments is very widespread at present, mainly due to the low rate of annual loss and, to date, few studies have assessed their survival in the routine clinical practice of dentistry. The purpose of this observational study was to evaluate the effectiveness of dental implants with a calcium-phosphate surface in the daily practice of dental clinics. A multicenter, prospective, non-interventional, observational study was performed, in which three experienced practitioners (one maxillofacial and two oral surgeons) inserted implants using standard external and internal hexagon connections in adult patients requiring ≥1 osseointegrated implants to replace missing teeth. Follow-up was performed for 24 months after implant loading. Two hundred and twelve subjects were included (51.5% men), with a mean age of 51.2 ± 11.90 years, in whom 544 implants were inserted. 87.2% of the patients received 1–4 implants. The preferred connection system was internal hexagon (73.5%). There were nine failures, with an interval survival rate (ISR) at 24 months of 100% and a cumulative survival rate (CSR) of 98.3%. In conclusion, implants with a modified calcium-phosphate surface are associated with a high rate of survival and may be considered a method of choice in clinical practice.

Effectiveness and compliance of an oscillating-rotating toothbrush in patients with dental implants: a randomized clinical trial

Background

The aim of this randomized clinical trial was to assess the efficacy of an oscillating-rotating toothbrush in reducing plaque and inflammation around dental implants.

Methods

Eighty patients presenting dental implants were enrolled in this study and assigned randomly to two different groups: 40 patients in the test group and 40 in the control one. Each patient in the test group received an oscillating-rotating toothbrush while in the control group patients kept using the manual toothbrush. Furthermore, the test group received a special toothbrush head designed for dental implants and another one for natural teeth. Domiciliary oral hygiene instructions were given to both groups. Periodontal parameters like plaque index (PI), bleeding on probing (BoP), and probing pocket depth (PPD) were recorded at the baseline and after 1 and 3 months.

Results

At the end of the study, the difference of plaque and bleeding indices with the baseline was statistically significant for both test and control groups (P < 0.0001). Implant sites showed higher values of both BoP and PI when compared to the natural teeth. In the second part of the study, comparing the 1–3-month period, the oscillating-rotating toothbrush was effective in reducing new plaque formation (P < 0.0001) and bleeding (P < 0.0001) both at the implant sites and the dental sites comparing to manual ones (P > 0.05). No significant differences were appreciated concerning the PPD.

Conclusions

The oscillating-rotating toothbrush can be successfully used for the plaque and bleeding control of the peri-implant tissues.

Clinical evaluation of non-surgical cleaning modalities on titanium dental implants during maintenance care: a 1-year follow-up on prosthodontic superstructures

OBJECTIVES

To investigate tissue health around implants with newly attached superstructures over 12 months of preventive maintenance appointments and instrumentation when necessary.

MATERIAL AND METHODS

In a randomized, split-mouth study 32 implants (8 participants with 4 implants each) received followed-up care every 3 months after superstructure attachment. Implants and superstructures were randomly assigned to four treatment groups and treated if necessary: (1) titanium curettes (TC), (2) stainless steel ultrasonic tip (PS), (3) erythritol air-polishing powder (EP), or (4) rubber cup polishing (CON). Probing depths (PDs), bleeding on probing (BOP), modified gingival (mucosal) bleeding index (GBI) around implants, and full-mouth Plaque Control Record (PCR) were measured every 3 months. Clinical attachment levels (CALs) and height of keratinized mucosa (KM)/gingival margins (GMs) for implants/teeth and PD, BOP, and GBI for teeth were documented at baseline, 6 months, and 12 months. Matrix metalloproteinase 8 (MMP-8) and periopathogens were measured at baseline and 12 months.

RESULTS

Participants exhibited minimal signs of periodontal inflammation with statistically significant PD improvement (3.0 ± 0.2 to 2.8 ± 0.3 mm; p = 0.022) and overall CAL (4.3 ± 0.8 to 4.0 ± 0.7 mm; p = 0.048) after 1 year. Implants showed no statistically significant differences (p > 0.05) between or within groups at baseline or 12 months for any parameter, except MMP-8 decreased significantly for PS (14.50 ± 17.58 to 4.63 ± 7.56 ng; p = 0.044), and after 12 months, PCR showed a significant difference between TC and PS (p = 0.018).

CONCLUSIONS

Treatment was necessary as inflammation was observed around newly placed superstructures within the first year of maintenance care. All tested treatment modalities yielded comparable clinical improvements.

CLINICAL RELEVANCE

Early assessment and diagnosis of mucositis and regular maintenance can promote long-lasting implant health.

Anaerobic Bacteria in Implants and Homologous Teeth 2-14 Years after Implantation

OBJECTIVE

The objective of the study was to establish whether there is a difference in the presence of potentially pathogenic anaerobic microorganisms around the implant and the homologous tooth in implant-prosthetic patients who received individual information about maintaining their oral hygiene.

MATERIAL AND METHODS

The study included 30 subjects with dental implants and metal-ceramic crowns. A periodontal probe was used to record the approximal plaque index (API), the papilla bleeding index (PBI), the periodontal pocket probing depth (PD) and the gingival recession. The fluid around the implant and the gingival sulcus fluid around the homologous tooth on the opposite lateral side were sampled.

RESULTS

The results have shown a positive API and PBI on 30% of the implants and a negative one on 70% of the implants. The average mucosal retraction measured around the implants was 0.15 mm, and the average probing depth was 2.25 mm. The API and PBI were positive on 78.3% of the homologous teeth. The average gingival retraction measured was 1.06 mm, and the average probing depth was 1.85 mm. Anaerobic bacteria were found in 12 out of 30 subjects (40%). Anaerobic bacteria were isolated only on the implant in 7 subjects, only on the homologous tooth in 3 subjects and both on the implant and the homologous tooth in 2 subjects.

CONCLUSIONS

Anaerobic bacteria were more abundantly present on implants than on homologous teeth.

Comprehensive rehabilitation using dental implants in generalized aggressive periodontitis

Generalized aggressive periodontitis (GAP) is a debilitating form of the disease and it results in deteriorating effects on the esthetic and functional aspects of the oral cavity. This case report describes the comprehensive rehabilitation of GAP patient using dental implants. The treatment planning involved thorough scaling and root planning (SRP) with oral hygiene instructions. The patient was motivated to adhere to a strict oral hygiene regimen following which periodontal flap surgery employing guided tissue regeneration and bone grafts was performed. Bacterial culture for anaerobic microorganisms was done using a gas pack pre- and postperiodontal treatment to confirm the effectiveness of the periodontal treatment regimen and also to proceed with dental implant placement. The rigorous maintenance program ensured the stability of the periodontium following which immediate placement of dental implants in the maxillary and mandibular anterior region was done. The fixed metal-ceramic prosthesis was fabricated in a step-by-step process and the patient was recalled on a periodic basis over a 3-year follow-up duration. This case is a testimonial to the postperiodontal treatment long-term stability with excellent patient cooperation and strict maintenance protocol.

Single Sitting Surgical Treatment of Generalized Aggressive Periodontitis Using GTR Technique and Immediate Implant Placement with 10-Year Follow-Up

This case report exhibits a patient with generalized aggressive periodontitis who has been under maintenance for the past 12 years after being surgically treated in a single sitting and restored with dental implants. A 41-year-old systemically healthy male patient presented complaining of lower anterior teeth mobility and pain in the upper right quadrant. After clinical and radiographic examination, the upper right molars and lower anterior incisors were deemed unrestorable. Covered by doxycycline, the patient received a nonsurgical periodontal treatment. Three weeks later, teeth extraction, immediate implant placement, immediate nonloading provisional prosthesis, and a guided tissue regeneration were performed at indicated areas in a single sitting. The clinical decisions were based on patient compliance, the status of the existing periodontal tissues, and the prognosis of the remaining teeth. During the 12-year follow-up period, no residual pockets were observed and there was no exacerbation of the inflammatory condition. Marginal bone stability is present on all implants. For aggressive periodontal disease, a high risk of relapse as well as limited success and survival of dental implants should be considered. This case shows proper containment of the disease based on appropriate treatment planning and a strict maintenance program.

The influence of direct laser metal sintering implants on the early stages of osseointegration in diabetic mini-pigs

Background

High failure rates of oral implants have been reported in diabetic patients due to the disruption of osseointegration. The aim of this study was to investigate whether direct laser metal sintering (DLMS) could improve osseointegration in diabetic animal models.

Methods

Surface characterizations were carried out on two types of implants. Cell morphology and the osteogenic-related gene expression of MG63 cells were observed under conditions of DLMS and microarc oxidation (MAO). A diabetes model in mini-pigs was established by intravenous injection of streptozotocin (150 mg/kg), and a total of 36 implants were inserted into the mandibular region. Micro-computed tomography (micro-CT) and histologic evaluations were performed 3 and 6 months after implantation.

Results

The Ra (the average of the absolute height of all points) of MAO surface was 2.3±0.3 µm while the DLMS surface showed the Ra of 27.4±1.1 µm. The cells on DLMS implants spread out more podia than those on MAO implants through cell morphology analysis. Osteogenic-related gene expression was also dramatically increased in the DLMS group. Obvious improvement was observed in the micro-CT and Van Gieson staining analyses of DLMS implants compared with MAO at 3 months, although this difference disappeared by 6 months. DLMS implants showed a higher bone–implant contact percentage (33.2%±11.2%) at 3 months compared with MAO group (18.9%±7.3%) while similar results were showed at 6 months between DLMS group (42.8%±10.1%) and MAO group (38.3%±10.8%).

Conclusion

The three-dimensional environment of implant surfaces with highly porous and fully interconnected channel and pore architectures can improve cell spreading and accelerate the progress of osseointegration in diabetic mini-pigs.

Outcomes of implant therapy in patients with a history of aggressive periodontitis. A systematic review and meta-analysis

OBJECTIVE

To investigate the outcomes of implant therapy in partially dentate patients treated for aggressive periodontitis (GAgP) in comparison to periodontally healthy (HP) and patients treated for chronic periodontitis (CP) utilizing radiographic and clinical parameters.

MATERIAL AND METHODS

An electronic search of databases, supplemented by hand searching, was conducted to identify relevant clinical studies. Sequential screenings at the title, abstract and full-text levels were performed independently and in duplicate. A random effects meta-analysis was conducted and bias corrected bootstrap 95 % confidence intervals were estimated for group comparisons.

RESULTS

The search strategy revealed a total of 899 results. After title screening, abstract scanning, and full-text reading, seven articles fulfilled the inclusion criteria. The 3-year survival rate for CP and HP patients was 100 % while in GAgP subjects, the respective value was 97.98 %; this difference being statistically significant. The 3-year mean marginal bone loss (MBL) was 1.07 mm for the GAgP group, 0.47 mm for the CP group, and 0.69 mm for the HP group. A significant difference between the GAgP and CP groups was identified (p < 0.05). The weighted mean differences of MBL concerning the above groups were also calculated and examined for statistical significance in both 1 and 3 years.

CONCLUSIONS

The 3-year survival rate and peri-implant marginal bone loss was found statistically significantly lower in GAgP subjects (SR 97.98 % vs 100 %) in comparison to HP and CP individuals.

CLINICAL RELEVANCE

The outcome of implant therapy in terms of survival rate and marginal bone loss is considered very important for the clinician in decision making when placing implants in patients with a history of aggressive periodontitis.