Chronic hyperglycemia as a risk factor in implant therapy

Adiponectin receptors agonist alters microbiota to improve implant osseointegration in diabetic mice

OBJECTIVE

Estimate the impact of Adiponectin receptors agonist (AdipoRon) on dental implant osseointegration in alveolar bone and explore the possible mechanism between saliva microbiota and AdipoRon in diabetic mice.

MATERIALS AND METHODS

Sixty C57BL/6 mice (male, 8 weeks old) were divided randomly into four groups according to different doses of AdipoRon: normoglycemic control group; DM control group; DM with a low dose of AdipoRon (5 mg/kg/day); and DM with a high dose of AdipoRon (50 mg/kg/day). Then, dental implants were placed in the palatal root socket in the first molar extraction mouse model. Micro-computed tomography, histology examination, immunohistochemical staining, and oral microbiota were explored to evaluate implant osseointegration.

RESULTS

AdipoRon treatment at 50 mg/kg markedly promoted dental implant osseointegration in diabetic mice, but AdipoRon treatment at 5 mg/kg was not effective. Moreover, distinct differences in the oral microbiota composition were shown between the diabetic mice and diabetic mice treated with AdipoRon at 50 mg/kg.

CONCLUSION

AdipoRon treatment at 50 mg/kg in diabetic mice could significantly increase dental implant osseointegration. The salivary microbiota might participate in the accelerated osseointegration progress of dental implants in AdipoRon treatment.

Glycemic Control and Implant Stability in Patients with Type II Diabetes: Narrative Review

Advancements in implant design, surface characteristics, and surgical protocols have made implant restorations safe and highly predictable procedures. Bone metabolism plays a central role in the success of implant therapy. Diabetes mellitus is a significant disease impacting bone metabolism, particularly during the initial stages of osseointegration and in long-term survival. Moreover, aging is linked to various systemic conditions, such as diabetes, which increase the susceptibility of the periodontium and teeth to disease, often resulting in tooth loss. Studies on the impact of glycemic control on the success and longevity of implant-prosthetic rehabilitation in diabetic patients highlight a significant association between hyperglycemia and complications in implant therapy. This review identified 18 relevant publications through Medline, and studies were screened against the aim and objectives of the review. A total of five articles were excluded because of lack of focus on the effect of glycemic control on dental implants. Diabetic patients with poorly controlled blood glucose levels may face a heightened risk of developing implant complications. Effective glycemic control plays a critical role in the long-term success of dental implants in these individuals. Marginal bone loss (MBL) is a critical indicator of implant health and success. Clinical studies generally show greater MBL in diabetic patients compared to non-diabetic individuals. Furthermore, controlled type 2 diabetes mellitus (T2DM) has been associated with significantly better maintenance.

Socket Preservation Using Platelet-Rich Fibrin and Free Gingival Grafts

OBJECTIVE

The present randomised controlled trial is based on the null hypothesis that there is no difference in crestal bone levels (CBLs) following socket preservation (SP) using platelet-rich fibrin (PRF) and free gingival graft (FGG). The aim was to evaluate CBLs following SP using PRF and FGG.

METHODS

This study is a parallel-arm randomised controlled trial. Patients in the test and control groups underwent SP using PRF and FGG, respectively. Intraoral visual examination was performed to clinically assess signs of swelling, pus/abscess, and stability of sutures and graft. Self-rated postoperative pain was assessed after 1 week and 6 months using the visual analogue scale (VAS). At the 6-month follow-up, cone-beam computed tomography was performed to evaluate CBL in mesiodistal and buccolingual dimensions. The preoperative cone-beam computed tomographic images were superimposed with those taken at the 6-month follow-up to compare CBLs. Statistical comparisons were performed and level of significance was set at P < .05.

RESULTS

The test and control groups each comprised 13 individuals with comparable ages. All teeth included in the test and control groups were located in the maxillary aesthetic zone. At the 1-week follow-up, VAS scores were higher in the control than in the test group (P < .01). At the 6-month follow-up, none of the participants reported self-rated pain. The change in buccolingual dimension was greater in the control group than in the test group (P < .05).

CONCLUSIONS

Both FGG and PRF are effective techniques for SP; however, the latter technique is more effcacious in maintaining buccolingual dimensions of the extraction socket.

Comparison of local minocycline hydrochloride delivery and antimicrobial photodynamic therapy as adjuncts to mechanical debridement for the treatment of peri‑implant mucositis: A randomized controlled trial

OBJECTIVE

The aim was to compare the efficacy of local minocycline hydrochloride delivery (LMHD) and antimicrobial photodynamic therapy (aPDT) as adjuncts to mechanical debridement (MD) for the treatment of peri‑implant mucositis (PM).

METHODS

Patients with PM were included. The following information was retrieved from patients' digital dental records: (a) age, (b) gender, (c) duration of implants in function, (d) number of implants, (e) depth of implant placement, and (f) mode of prosthesis retention. Information related to daily toothbrushing and flossing of interproximal spaces and the most recent visit to an oral healthcare provider was also recorded. Participants were randomly divided into three groups as follows: (a) MD + LMHD; (b) MD + aPDT, and (c) MD alone. Peri-implant modified plaque index (mPI), modified gingival index (mGI) and probing depth (PD) were measured at baseline and at 45 days follow-up. Peri-implant crestal bone levels were measured at baseline. Group comparisons were done using One-way analysis of variance and Bonferroni post-hoc adjustment tests. The correlation between peri‑implant clinical parameters and age, gender, and duration of implants in function was assessed using linear regression analysis. Level of significance was set at P < 0.05.

RESULTS

Twenty-two and 22 patients underwent MD with adjunct LMDH and aPDT, respectively. Twenty-two participants underwent MD alone. There was no difference in the mean ages of all individuals. At baseline, there was no difference in mPI, mGI and PD in all groups. At follow-up, mPI (P < 0.05), mGI (P < 0.05) and PD (P < 0.05) were higher among patients who underwent MD alone than individuals who received LMHD or aPDT as adjuncts to MD. There was no difference in mPI, mGI, and PD among individuals who underwent LMHD and aPDT as adjuvants to MD.

CONCLUSION

In the short term, MD with adjunct LMHD or aPDT is effective for managing PM.

Diabetes mellitus exacerbates inflammation in a murine model of ligature-induced peri-implantitis: A histological and microtomographic study

AIM

To investigate the influence of diabetes mellitus (DM) in a murine model of peri-implantitis (PI).

MATERIALS AND METHODS

Twenty-seven 4-week-old C57BL/6J male mice had their first and second maxillary left molars extracted. Eight weeks later, one machined implant was placed in each mouse. Four weeks after osseointegration, the mice were divided into three groups: (a) control (C), (b) PI and (c) DM + PI. DM was induced by streptozotocin (STZ) administration. After DM induction, PI was induced using ligatures for 2 weeks. The hemimaxillae were collected for micro-CT and histological analyses. The primary outcomes consisted of linear (mm) and volumetric (mm3) bone loss. Secondary outcomes were based on histological analysis and included inflammatory infiltrate, osteoclastic activity, matrix organization, composition and remodelling. Data are presented as means ± SEM. Statistical analyses were performed using one-way ANOVA, followed by Tukey's test.

RESULTS

Gingival tissue oedema was detected in the PI and DM + PI groups. Micro-CT showed significantly increased linear and volumetric bone loss in the DM + PI group compared to the C and PI groups. H&E staining showed greater inflammatory response and bone resorption in the PI and DM + PI groups than in the C group. The DM + PI group had significantly higher osteoclast numbers than the C and PI groups. Picrosirius red stained less for types I and III collagen in the PI and DM + PI groups than in the C group. There was a significant increase in monocyte/macrophage (CD-11b) counts and matrix metalloproteinases (MMP-2 and MMP-8) marker levels and a significant decrease in the matrix metalloproteinases inhibition marker (TIMP-2) levels in the DM + PI group compared to the C and PI groups.

CONCLUSIONS

DM exacerbates PI-induced soft-tissue inflammation, matrix degradation and bone loss.

Risk factors for Peri-implantitis: An umbrella review of meta-analyses of observational studies and assessment of biases

OBJECTIVES

To perform a comprehensive quantitative and qualitative analysis of the findings from previously published meta-analyses and to assess existing biases.

DATA/SOURCES

A search was conducted for meta-analyses of observational studies investigating the association between any risk factor and peri‑implantitis in PubMed, Scopus, Cochrane Database of Systematic Reviews, and Epistemonikos, from inception until October 2023 (PROSPERO: CRD42024512408).

STUDY SELECTION

From a total of 5002 publications, 51 full-text articles were evaluated for eligibility, and 12 articles that described 41 unique meta-analyses evaluating the association between risk factors and periimplantitis were selected. Among 41 associations, 24 associations were significant. None of the associations were graded as convincing evidence. Two associations, presence of periodontitis (OR = 3.84 [95 % CI 2.58,5.72]) and cigarette smoking (RR=2.07 [95 % CI 1.41,3.04]) were graded as highly suggestive. Eight associations, diabetes mellitus, hyperglycaemia, lack of prophylaxis, history of chronic periodontal disease, ongoing or history of periodontal disease, implants located in the anterior region of the jaw (maxillary and mandibular), osteoprotegerin (OPG) gene polymorphisms, and lack of keratinized mucosal width were graded as suggestive evidence.

CONCLUSIONS

Periodontitis and cigarette smoking are highly suggestive risk factors for peri‑implantitis. The remaining risk factors which are suggestive require more high-quality studies to be performed to upgrade the level of evidence.

CLINICAL SIGNIFICANCE

The highly suggestive and suggestive risk factors for peri‑implantitis summarized in this umbrella review should be rigorously assessed, monitored and managed by clinicians to reduce the risk peri‑implantitis, as well as to form part of the preoperative consent process.

Insight of the interrelationship and association mechanism between periodontitis and diabetes mellitus

Periodontitis and diabetes mellitus are two prevalent chronic diseases that have been recognized to exhibit a bidirectional relationship. Individuals with diabetes are more susceptible to periodontitis, and conversely, periodontitis can exacerbate glycemic control in diabetic patients. The underlying mechanisms of this interrelationship involve complex pathways, including inflammatory responses, altered immune functions, and microbial dysbiosis. The mechanistic insights into the interrelationship between periodontitis and diabetes mellitus revolve around the role of inflammation as a common link between the two diseases. Inflammatory mediators such as cytokines, chemokines, and prostaglandins play a crucial role in the pathogenesis and progression of the diseases. The dysregulation of the immune response in diabetes can exacerbate the inflammatory response in periodontitis, leading to increased tissue destruction and bone resorption. The chronic inflammation in periodontitis can contribute to insulin resistance and impaired glycemic control in diabetic patients. Future directions in research aim to further elucidate the molecular mechanisms underlying the interrelationship between periodontitis and diabetes mellitus. Modulating the inflammatory response, restoring microbial balance, and improving glycemic control hold promise in managing both conditions simultaneously. Herein, we will provide an overview of the interrelationship of periodontitis and diabetes mellitus, and retrospect the underlying mechanisms, which may inspire investigators with further research directions.

Calcium phytate reverses high glucose-inhibited osteogenesis of BMSCs via the MAPK/JNK pathway

OBJECTIVES

Diabetes mellitus (DM) induces oxidative tissue impairment and suppresses bone formation. Some studies have shown that phytic acid has antioxidant and anti-diabetic properties. This study aimed to investigate the potential of calcium phytate (Ca-phytate) to reverse inhibited osteogenesis of human bone marrow mesenchymal stem cells (hBMSCs) in a high glucose (HG) environment and to determine the underlying mechanism.

MATERIALS AND METHODS

hBMSCs were exposed to HG and palmitic acid to simulate DM in vitro. Osteogenic differentiation was measured using alkaline phosphatase staining and activity assay, alizarin red S staining, qRT-PCR, Western blot and immunofluorescence staining. A critical-size cranial defect model of type 2 diabetes mellitus (T2DM) rats was established to evaluate bone regeneration. A specific pathway inhibitor was used to explore whether the MAPK/JNK pathway was involved.

RESULTS

Treatment with 34 μM Ca-phytate had the highest effect on osteogenic differentiation in HG. Ca-phytate improved cranial bone defect healing in T2DM rats. The long-term HG environment inhibited the activation of the MAPK/JNK signalling pathway, which was restored by Ca-phytate. Blocking the JNK pathway reduced the Ca-phytate-mediated osteogenic differentiation of hBMSCs.

CONCLUSION

Ca-phytate induced bone regeneration in vivo and reversed HG-inhibited osteogenesis of hBMSCs in vitro via the MAPK/JNK signalling pathway.

Effect and mechanism of fluctuant glucose on restraining implant osseointegration in diabetes

OBJECTIVES

The objectives of the study was to discuss the effect and mechanism of fluctuant glucose (FG) on implant osseointegration in type 2 diabetic mellitus (T2DM).

MATERIALS AND METHODS

Rats were divided into control, T2DM and FG group, and the implants were inserted into their femurs. Micro-CT and histological analysis were used to evaluate the effect on osseointegration in vivo. And we investigated the effect of different conditions (normal, control, high glucose, and FG medium) on rat osteoblast in vitro. Then transmission electron microscope (TEM) and Western blot were used to evaluate the endoplasmic reticulum stress (ERS) response. Finally, 4-PBA, an inhibitor of ERS, was added into different conditions to observe the functions of osteoblast.

RESULTS

In vivo, Micro-CT and histological analysis showed that the percentage of osseointegration in FG rats were lower than other two group. In vitro, the results demonstrated that the adhesion of the cells becomes worst, and osteogenic ability was also severely impaired in FG group. In addition, FG could induce more serious ERS and 4-PBA could improve the dysfunction of osteoblasts induced by FG.

CONCLUSION

Fluctuant glucose could restrain the implant osseointegration in T2DM, and the effect was more obvious than consistent high glucose by a possible mechanism of activation ERS pathway.

Dental Implant Placement in Medically Compromised Patients: A Literature Review

As a discipline of dentistry, oral implantology deals with the diagnosis, design, insertion, restoration, and/or management of alloplastic or autogenous oral structures for the purpose of regaining contour, function, aesthetics, and speech in a partially or completely edentulous patient. The present review aims to provide the currently available knowledge about the impact of certain systemic disorders and the usage of some medications on the survival rate of dental implant therapy and to highlight the importance of patient management under these conditions. Diabetes, osteoporosis, cardiovascular diseases, and the intake of some medications can increase the risk of the failure of a dental implant. Even though there are relatively few medical contraindications to dental implant treatment, certain conditions may increase the risk of failure or complications.

Magnesium promotes vascularization and osseointegration in diabetic states

Diabetes has long been considered a risk factor in implant therapy and impaired wound healing in soft and hard oral tissues. Magnesium has been proved to promote bone healing under normal conditions. Here, we elucidate the mechanism by which Mg2+ promotes angiogenesis and osseointegration in diabetic status. We generated a diabetic mice model and demonstrated the alveolar bone healing was compromised, with significantly decreased angiogenesis. We then developed Mg-coating implants with hydrothermal synthesis. These implants successfully improved the vascularization and osseointegration in diabetic status. Mechanically, Mg2+ promoted the degradation of Kelch-like ECH-associated protein 1 (Keap1) and the nucleation of nuclear factor erythroid 2-related factor 2 (Nrf2) by up-regulating the expression of sestrin 2 (SESN2) in endothelial cells, thus reducing the elevated levels of oxidative stress in mitochondria and relieving endothelial cell dysfunction under hyperglycemia. Altogether, our data suggested that Mg2+ promoted angiogenesis and osseointegration in diabetic mice by regulating endothelial mitochondrial metabolism.

Bone structure and composition in a hyperglycemic, obese, and leptin receptor-deficient rat: Microscale characterization of femur and calvarium

Metabolic abnormalities, such as diabetes mellitus and obesity, can impact bone quantity and/or bone quality. In this work, we characterize bone material properties, in terms of structure and composition, in a novel rat model with congenic leptin receptor (LepR) deficiency, severe obesity, and hyperglycemia (type 2 diabetes-like condition). Femurs and calvaria (parietal region) from 20-week-old male rats are examined to probe bones formed both by endochondral and intramembranous ossification. Compared to the healthy controls, the LepR-deficient animals display significant alterations in femur microarchitecture and in calvarium morphology when analyzed by micro-computed X-ray tomography (micro-CT). In particular, shorter femurs with reduced bone volume, combined with thinner parietal bones and shorter sagittal suture, point towards a delay in the skeletal development of the LepR-deficient rodents. On the other hand, LepR-deficient animals and healthy controls display analogous bone matrix composition, which is assessed in terms of tissue mineral density by micro-CT, degree of mineralization by quantitative backscattered electron imaging, and various metrics extrapolated from Raman hyperspectral images. Some specific microstructural features, i.e., mineralized cartilage islands in the femurs and hyper-mineralized areas in the parietal bones, also show comparable distribution and characteristics in both groups. Overall, the altered bone microarchitecture in the LepR-deficient animals indicates compromised bone quality, despite the normal bone matrix composition. The delayed development is also consistent with observations in humans with congenic Lep/LepR deficiency, making this animal model a suitable candidate for translational research.

Role of Chlorhexidine and Herbal Oral Rinses in Managing Periodontitis

OBJECTIVE

The aim of this research was to assess the effect of 0.12% chlorhexidine (CHX) and a Salvadora persica-based mouthwash on whole salivary tumour necrosis factor-alpha (TNF-α) levels and periodontal inflammation in patients with type 2 diabetes mellitus (T2DM).

METHODS

Patients with and without medically diagnosed T2DM were included. Patients' medical records were evaluated to confirm the diagnosis of T2DM. All patients underwent nonsurgical periodontal therapy (NSPT). Patients were divided into 2 subgroups. In the test and control group, patients were advised to rinse with an S persica-based mouthwash and a non-alcoholic 0.12% CHX after NSPT twice daily for 2 weeks, respectively. Demographic data were collected. Full-mouth plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment loss (AL) were measured, and whole salivary TNF-α levels were gauged at baseline and at 3-month follow-up. Haemoglobin A1c (HbA1c) levels were measured in all patients at baseline and at 3-month follow-up. Sample size estimation was done, and group comparison was performed. Level of significance was set at P < .01.

RESULTS

Twenty-one nondiabetic individuals and 21 patients with T2DM were included. At baseline, there was no significant difference in clinical and radiographic periodontal parameters amongst in patients with and without T2DM. At 3-month follow-up, HbA1c, TNF-α, PI, PD, and clinical AL were comparable with their respective baseline values in the test and control groups amongst patients with T2DM. In nondiabetic individuals, there was a significant reduction in PI (P < .01), GI (P < .01), and PD (P < .01), and TNF-α (P < .01) at 3-month follow-up in the test and control groups compared with their respective baseline scores.

CONCLUSIONS

In the short term, NSPT with 0.12% CHX or S persica-based mouthwashes is more effective in reducing periodontal inflammation and whole salivary TNF-α levels in nondiabetic individuals than in patients with T2DM with periodontal inflammation.

In-Vitro Evaluation of Photofunctionalized Implant Surfaces in a High-Glucose Microenvironment Simulating Diabetics

The present study aimed to assess the efficacy of photofunctionalization on commercially available dental implant surfaces in a high-glucose environment. Discs of three commercially available implant surfaces were selected with various nano- and microstructural alterations (Group 1—laser-etched implant surface, Group 2—titanium–zirconium alloy surface, Group 3—air-abraded, large grit, acid-etched surface). They were subjected to photo-functionalization through UV irradiation for 60 and 90 min. X-ray photoelectron spectroscopy (XPS) was used to analyze the implant surface chemical composition before and after photo-functionalization. The growth and bioactivity of MG63 osteoblasts in the presence of photofunctionalized discs was assessed in cell culture medium containing elevated glucose concentration. The normal osteoblast morphology and spreading behavior were assessed under fluorescence and phase-contrast microscope. MTT (3-(4,5 Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and alizarin red assay were performed to assess the osteoblastic cell viability and mineralization efficiency. Following photofunctionalization, all three implant groups exhibited a reduced carbon content, conversion of Ti4+ to Ti3+, increased osteoblastic adhesion, viability, and increased mineralization. The best osteoblastic adhesion in the medium with increased glucose was seen in Group 3. Photofunctionalization altered the implant surface chemistry by reducing the surface carbon content, probably rendering the surfaces more hydrophilic and conducive for osteoblastic adherence and subsequent mineralization in high-glucose environment.

Comparison of the postoperative anti-inflammatory efficacy of chlorhexidine, saline rinses and herbal mouthwashes after mechanical debridement in patients with peri-implant mucositis: A randomized controlled trial

AIM

The null hypothesis is that there is no difference in the post-operative anti-inflammatory efficacy of chlorhexidine (CHX), 2% saline rinses (SR) and a herbal mouthwash (MW) after non-surgical mechanical debridement (MD) for treatment of peri-implant mucositis (PiM). The aim was to compare the post-operative anti-inflammatory efficacy of CHX, 2% SR and a herbal oral rinse after non-surgical MD of PiM.

MATERIALS AND METHODS

The present randomized controlled trial had a single-blinded parallel arm design. Patients diagnosed with PiM were enrolled. Demographic information was recorded. All patients underwent MD and were randomly divided into 4 groups: CHX-group: 0.12% non-alcoholic CHX; Sodium chloride (NaCl) group: 2% NaCl rinses; Herbal MW group: Herbal-based MW and H₂ O group: distilled water with peppermint flavour. After MD, all the participants were advised to rinse twice daily (every 12 hrs) for 2 weeks with their respective MWs. In all groups, peri-implant modified plaque index (mPI), modified gingival index (mGI) and probing depth (PD) were measured at baseline and at 12 weeks of follow-up. Sample size was estimated using data from a pilot investigation; and group-comparisons were performed. Statistical significance was confirmed when P-values were below 0.01.

RESULTS

Sixty individuals (15 patients/group) were included. At baseline, mPI, mGI and PD were comparable in all groups. At baseline, there was no significant difference in peri-implant mPI, mGI and PD in all groups. At 12-weeks' follow-up, there was a statistically significant reduction in peri-implant mPI (p < 0.01), mGI (p < 0.01) and PD (p < 0.01) in CHX, NaCl and herbal MW groups compared with H₂ O group. There was no significant relation between implant location, duration for which, implants were functional, gender and peri-implant clinical parameters in all groups.

CONCLUSION

After non-surgical MD, post-operative use of CHX and herbal and NaCl MWs is useful for the management of PiM in the short-term.

Levels of peri-implant sulcular fluid levels of soluble urokinase plasminogen activator receptor and TNF-α among cigarette smokers and non-smokers with peri-implantitis

BACKGROUND

Soluble urokinase plasminogen activator receptor (suPAR) and tumor necrosis factor-alpha (TNF-α) are inflammatory biomarkers. No studies have yet assessed the suPAR levels in relation with TNF-α in the peri-implant sulcular fluid (PISF) among cigarette smokers and non-smokers with peri-implantitis.

OBJECTIVE

The aim was to evaluate PISF levels of suPAR, and TNF-α among cigarette smokers and non-smokers with and without peri-implantitis.

METHODS

Sixty male patients with peri-implantitis were included. There were 20 cigarette smokers and 20 and non-smokers with peri-implantitis (Groups 1 and 2), and 20 non-smokers without peri-implantitis (Group 3). Demographic data and information related to cigarette smoking was recorded. Peri-implant clinicoradiographic parameters (plaque index [PI], gingival index [GI], probing depth [PD] and crestal bone loss [CBL]) were assessed. The PISF samples were collected and levels of suPAR and TNF-α were measured. Sample-size estimation was performed and all parameters were statistically assessed. Level of significance was set at P< 0.05.

RESULTS

Sixty individuals were included in Groups 1, 2 and 3 (20 in each). Peri-implant PI (P< 0.01), PD (P< 0.01) and mesial (P< 0.01) and distal (P< 0.01) CBL were significantly higher in Group 1 than in Groups 2 and 3. The PISF volume (P< 0.01) and suPAR (P< 0.01) and TNF-α levels (P< 0.01) were significantly higher in Groups 1 and 2 than in Group 3. There was no difference in PISF volume and suPAR and TNF-α levels between patients in Groups 1 and 2. In Group 2, there was a statistically significant correlation between peri-implant PD and PISF suPAR and TNF-α levels (P< 0.01). The suPAR and TNF-α levels are expressed in high concentrations in the PISF of smokers and non-smokers with peri-implantitis compared with non-smokers without peri-implantitis.

CONCLUSION

In non-smokers, PISF suPAR and TNF-α levels are correlated with peri-implant PD.

Impact of local predisposing/precipitating factors and systemic drivers on peri‐implant diseases

BACKGROUND

Strong evidence suggests the infectious nature of peri-implant diseases occurring in susceptible hosts. Epidemiological reports, though, indicate that peri-implantitis is a site-specific entity. Hence, the significance of local factors that may predispose/precipitate plaque accumulation and the impact of systemic drivers that alter the immune response are relevant in the prevention and management of peri-implant disorders.

PURPOSE

The purpose of the present review is to shed light on the significance of local and systemic factors on peri-implant diseases, making special emphasis on the associations with peri-implantitis.

METHODS

The biologic plausibility and supporting evidence aiming at providing a concluding remark were explored in the recent scientific literature for local predisposing/precipitating factors and systemic drivers related to peri-implant diseases.

RESULTS

Local predisposing factors such as soft tissue characteristics, implant position and prosthetic design proved being strongly associated with the occurrence of peri-implant diseases. Hard tissue characteristics, however, failed to demonstrate having a direct association with peri-implant diseases. Robust data points toward the strong link between residual sub-mucosal cement and peri-implant diseases, while limited data suggests the impact of residual sub-mucosal floss and peri-implantitis. Systemic drivers/habits such as hyperglycemia and smoking showed a strong negative impact on peri-implantitis. However, there is insufficient evidence to claim for any link between metabolic syndrome, atherosclerotic cardiovascular disease, and obesity and peri-implant diseases.

CONCLUSION

Local predisposing/precipitating factors and systemic drivers may increase the risk of peri-implant diseases. Therefore, comprehensive anamnesis of the patients, educational/motivational programs and exhaustive prosthetically-driven treatment planning must be fostered aiming at reducing the rate of biological complications in implant dentistry.

Effect of Anti-Diabetic Medications on Dental Implants: A Scoping Review of Animal Studies and Their Relevance to Humans

Animal studies have ascertained that hyperglycemia adversely affects bone metabolism and dental implant osseointegration. However, diabetic patients show low occurrence of unfavorable hard or soft peri-implant tissue changes, differences that are possibly due to treatment with anti-diabetic medications. This scoping review aimed to systematically examine the effects of these drugs on implant outcomes and explore the predictive modality of animal studies for clinical practice according to type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). Three electronic databases (MEDLINE, EBSCOHost, and Cochrane) were searched according to the PRISMA-ScR standards for studies on diabetic animals that received titanium implants and anti-diabetic treatments. Risk assessment was performed using the SYRCLE Risk-of-Bias (RoB) tool. Twenty-one papers were included, encompassing six types of medications. Fifteen studies were on T1DM animals, and only six involved T2DM models. T1DM animals were treated with non-insulin drugs in four investigations, while insulin was utilized in 11 other studies. In T2DM experiments, five administered non-insulin drugs, and only one applied locally delivered insulin. Only insulin in T1DM studies produced a positive influence on bone-implant contact (BIC), bone mineral content, and removal torque values. Inappropriate drug selection, inadequate glycemic control, and high RoB depict a mismatch between the research focus and the translational rationale to clinical practice. There remains a knowledge gap regarding T2DM investigations due to the lack of studies. More data are needed concerning intraoral implants and the performance of osseointegrated implants in patients with a later onset of diabetes. Future research should reflect the pathophysiology and treatment of each type of diabetes to ensure clinical applicability.

The Effect of Laser Micro Grooved Platform Switched Implants and Abutments on Early Crestal Bone Levels and Peri-Implant Soft Tissues Post 1 Year Loading among Diabetic Patients-A Controlled Clinical Trial

Background and Objectives: The study aimed to compare the mean crestal bone level (CBL) and peri-implant soft tissue parameters in laser micro-grooved (LMG) platform switched implants and abutments (I&A) post 1 year of functional loading among non-diabetic and type II diabetic individuals. Materials and methods: Patients with an edentulous site having minimum bone height and width of ≥13 mm and ≥6 mm, respectively, were divided into two groups: (i) Non-diabetic-8 (control) and (ii) diabetic-8 (test). LMG Implants were placed and loaded immediately with a provisional prosthesis. Mean crestal bone level (MCBL) was evaluated radiographically at baseline and at 1 year. Peri-implant attachment level (PIAL) and relative position of the gingival margin (R-PGM) were recorded. Implant stability quotient (ISQ) level and implant survival rate (ISR) were evaluated at 1 year. Results: Early MCBL within the groups 1 year postloading was similar both mesially and distally (control-0.00 to 0.16 mm and 0.00 to 0.17 mm, respectively; test-0.00 to 0.21 mm and 0.00 to 0.22 mm, respectively) with statistical significance (p ≤ 0.003, p ≤ 0.001 and p ≤ 0.001, p ≤ 0.001, respectively). However, intergroup comparison showed no significant difference statistically in the MCBL in 1 year post functional loading. The peri-implant soft tissue parameters showed no significant difference between the groups. ISQ level between both groups did not reveal any significant changes (p ≤ 0.92), and ISR was 100%. Conclusions: LMG Implants resulted in minimal and comparable early crestal bone loss and soft tissue changes post 1 year of functional loading in moderately controlled diabetic and non-diabetic individuals, suggesting that this could be a reliable system for use in systemically compromised individuals.

Maresin1 Suppresses High-Glucose-Induced Ferroptosis in Osteoblasts via NRF2 Activation in Type 2 Diabetic Osteoporosis

Maresin1 (MaR1) is an endogenous pro-resolving lipid mediator produced from polyunsaturated fatty acids and is believed to have antioxidant and anti-inflammatory properties. The objective of this study was to estimate MaR1′s impact on type 2 diabetic osteoporosis (T2DOP) and its pharmacological mode of action. An in vitro high-glucose model of the osteoblast cell line MC3T3-E1 was constructed and stimulated with MaR1. Type 2 diabetic rats were used to establish in vivo models of calvarial defects and were treated in situ with MaR1. The results revealed that, aside from preventing mortality and promoting the osteogenic capacity of MC3T3-E1 cells, MaR1 increased nuclear factor erythroid-2 related factor 2 (NRF2) signaling as well as the activity of glutathione peroxidase 4 (GPX4) and cystine-glutamate antiporter (SLC7A11) and caused the restraint of ferroptosis under hyperglycemic stimulation. However, the therapeutic impact of MaR1 was significantly diminished due to NRF2-siRNA interference and the ferroptosis activator Erastin. Meanwhile, these results were validated through in vivo experiments. These findings imply that MaR1 activated the NRF2 pathway in vivo and in vitro to alleviate high-glucose-induced ferroptosis greatly. More crucially, MaR1 might effectively reduce the risk of T2DOP.

Assessment of salivary alpha amylase and mucin-4 before and after non-surgical treatment of peri-implant mucositis

BACKGROUND

The present study was based on the null hypothesis that there is no difference in clinicoradiographic parameters and whole salivary alpha amylase (AA) and mucin-4 levels before and after non-surgical mechanical debridement (NSMD) of patients with peri-implant mucositis (PM). The aim was to assess whole salivary AA and mucin-4 levels before and after treatment of PM.

METHODS

Patients with PM (Group-1) and individuals without peri-implant diseases (Group-2) were included. Demographic data was collected and peri-implant modified plaque and bleeding indices (mPI and mBI, respectively), probing depth (PD) and crestal bone loss were measured at baseline. Levels of AA and mucin-4 were assessed in unstimulated whole saliva samples. All patients underwent full-mouth non-surgical periodontal therapy (NSPT) and NSMD; and clinical parameters and salivary biomarkers were re-assessed after 3 months. Level of significance was set at P < 0.01.

RESULTS

Twenty-six and 32 individuals were included in groups 1 and 2, respectively. None of the participants had periodontitis. At baseline clinical periodontal parameters (PI [P < 0.001], GI [P < 0.001], clinical AL [P < 0.001] and PD [P < 0.001]) were significantly high in Group-1 than Group-2. At 3-month follow-up, there was a statistically significant reduction in clinical periodontal and peri-implant parameters (PI [P < 0.01], GI [P < 0.01], and PD [P < 0.01]) in Group-1 compared with their baseline values. At baseline, salivary AA levels were significantly high in Group-1 than Group-2 (P < 0.01). At 3-month follow-up, there was no significant difference in whole salivary AA levels among patients in groups 1 and 2.

CONCLUSIONS

The AA and mucin-4 levels are potential biomarkers for evaluation of peri-implant diseases including PM. Mechanical instrumentation continues to be the most predictable treatment option for the management of peri-implant diseases.

Disinfection of implant abutment connection using antimicrobial photodynamic therapy and 0.2% chlorhexidine gel applications immediately before prosthesis delivery: Clinical and radiographic status at 1-year of follow-up

OBJECTIVE

The aim of this 1-year follow-up randomized control trial was to compare the clinicoradiographic status of implants that were disinfected with antimicrobial photodynamic therapy (aPDT) and 0.2% chlorhexidine gel immediately before prosthesis delivery.

METHODS

Forty-five partially edentulous patients with implants placed in the region of missing mandibular first molars and a history of periodontal diseases were included. Immediately before prosthesis delivery, patients were divided into three groups. In groups 1 and 2, implant abutment disinfection (IAD) was performed using aPDT and 0.2% chlorhexidine immediately before prosthesis delivery. In Group-3, IAD was performed using a steaming protocol. Peri-implant modified plaque index (mPI), modified gingival index (mGI), probing depth (PD) and crestal bone loss (CBL) were assessed at 1 year of follow-up. Power analysis was done and group comparisons were done. Logistic regression analysis was done to corelate clinical parameters with demographic variables. P<0.01 was considered statistically significant.

RESULTS

In total, 15, 15, and 15 implants were present among patients in groups 1, 2 and 3, respectively. There was no statistically significant difference in peri-implant mPI, mBoP, PD and CBL in all groups (Table 2). None of the patients had periodontal disease and there was no statistically significant correlation between peri-implant clinicoradiographic parameters with age, toothbrushing and flossing habits, and duration of implants in function. Eighty percent, 86.7% and 100% individuals in groups 1, 2 and 3, respectively reported that they were brushing teeth twice daily. Flossing of interproximal spaces once daily was reported by 66.7%, 73.3% and 66.7% individuals in groups 1, 2 and 3, respectively.

CONCLUSION

As long as oral hygiene is stringently maintained after implant prosthesis delivery, IAD can be performed using aPDT, 0.2% CHX gel or steam-disinfection.

Effect of photobiomodulation after non-surgical mechanical debridement on cortisol levels in the peri-implant sulcular fluid among patients with peri-implant mucositis

OBJECTIVE

The aim of this was to compare the efficacy of photobiomodulation after non-surgical mechanical debridement (MD) on cortisol levels (CL) in peri-implant sulcular fluid (PISF) among patients with peri-implant mucositis.

METHODS

Patients with peri-implant mucositis were encompassed. All patients underwent non-surgical MD with (test group) and without (control group) a single application of photobiomodulation. Demographic data were collected and PISF was collected. Peri-implant modified plaque index (mPI), modified gingival index (mGI), probing depth and crestal bone loss were measured, and CL in PISF were recorded. All clinical parameters and PISF CL were re-assessed at 4 months of follow-up. p < .05 showed statistical significance.

RESULTS

Seventeen (14 males and 3 females) and 17 (15 males and 2 females) patients with peri-implant mucositis were recruited in test and control groups. The mean age of patients in the test and control groups was 46.1 ± 6.5 and 50.2 ± 2.7 years respectively. At baseline, mPI, mGI, PD and PISF volume and CL in control and test groups were similar. At follow-up, there was a significant reduction in mPI (p < .001), mGI (p < .001), PD (p < .001) and PISF volume (p < .001) and CL (p < .001) in both groups compared with baseline. There was no difference in mPI, mGI, PD and PISF volume and CL in test and control groups at follow-up.

CONCLUSION

In short term, non-surgical MD with photobiomodulation does not offer additional benefits in terms of reducing soft-tissue inflammatory parameters and PISF CL in patients with peri-implant mucositis.

Should the Quality of Glycemic Control Guide Dental Implant Therapy in Patients with Diabetes? Focus on Implant Survival

INTRODUCTION

Optimal glycemic control is crucial to dental implant long-term functional and esthetic success. Despite HbA1c levels of 7% or lower used is as an indicator for good glycemic control, however, this level may not be attainable for all diabetic patients. Most dentists do not consider patients with poor glycemic control candidates for implant therapy due to higher implant failure, infection or other complications.

AIM

This review challenges the concept of one size fits all and aims to critically appraise the evidence for the success or failure rate of dental implants and peri-implant health outcomes in patients with less than optimal glycemic control.

DISCUSSION

Evidence suggests that estimating glycemic control from HbA1c measurement alone is misleading. Moreover, elevated preoperative HbA1c was not associated with increased mortality and morbidity after major surgical procedures. Literature for the survival or success of implants in diabetic patients is inconsistent due to a lack of standardized reporting of clinical data collection and outcomes. While a number of studies report that implant treatment in patients with well controlled diabetes has a similar success rate to healthy individuals, other studies suggest that the quality of glycemic control in diabetic patients does not make a difference in the implant failure rate or marginal bone loss. This discrepancy could indicate that risk factors other than hyperglycemia may contribute to the survival of implants in diabetic patients.

CONCLUSION

In the era of personalized medicine, the clinician should utilize individualized information and analyze all risk factors to provide the patient with evidence-based treatment options.

Effect of multiple sessions of photodynamic therapy on bone regeneration around dental implants among patients with peri-implantitis

OBJECTIVE

The aim of the present study was to assess the effect of multiple sessions of antimicrobial photodynamic therapy (aPDT) on bone regeneration around dental implants among patients with peri-implantitis.

METHODS

Patients with peri-implantitis were included. Therapeutically, patients were randomly divided into 4 groups: (a) Group-I: Mechanical debridement (MD) alone; (b) Group-II: MD at baseline followed by a single session of adjunct a PDT; (c) Group-III: MD at baseline followed by aPDT at baseline and at 3-months of follow-up; and Group-IV: MD at baseline followed by aPDT at baseline and at 3- and 6-months of follow-up. Demographic data was collected and peri-implant clinical (plaque index [PI], gingival index [GI], and probing depth [PD]) and radiographic (crestal bone loss [CBL]) parameters were assessed at baseline and after 9 months. Sample-size estimation was done on data from a pilot investigation and group comparisons were done using one-way analysis of variance and Bonferroni post-hoc adjustment tests. Level of significance was set at P<0.01.

RESULTS

Twenty-two, 22, 22 and 22 patients with peri-implantitis were enrolled in groups -I, -II, -III and -IV. The mean age of individuals in groups -I, -II, -III and -IV were 59.2 ± 5.3, 60.5 ± 2.8, 59.6 ± 3.1 and 58.7 ± 0.8 years, respectively. Compared with Group-I, there was a statistically significant reduction in PI (P<0.01), GI (P<0.01) and PD (P<0.01) in all groups at 9-months follow-up. There was no significant difference in PI, GI and PD in groups -II, -III and -IV at 9-months follow-up. There was no statistically significant difference in CBL in all groups at baseline and at 9-months-follow-up.

CONCLUSION

The use of aPDT as an adjunct to MD reduces the severity of peri-implant mucositis but does not contribute towards bone regeneration in peri-implant osseous defects.

Survival rate and peri-implant evaluation of immediately loaded dental implants in individuals with type 2 diabetes mellitus: a systematic review and meta-analysis

Objectives

To evaluate the survival rate, success rate, and peri-implant biological changes of immediately loaded dental implants (ILs) placed in type 2 diabetic patients (DM2).

Materials and methods

The present study was registered on PROSPERO and followed the PRISMA checklist. The search was performed by the first reviewer in January 2021. The electronic databases used were MEDLINE via PubMed, Cochrane, BVS, Web of Science, Scopus, LIVIVO, and gray literature. The risk of bias analysis was performed using an instrument from the Joanna Briggs Institute.

Results

A total of 3566 titles and abstracts were obtained. The qualitative synthesis included 7 studies, while the quantitative synthesis included 5 studies. The meta-analysis of IL in individuals with DM2 compared to nondiabetic individuals showed no significant difference among the groups regarding the survival rate of dental implants (RR = 1.00, 95% CI 0.96–1.04; p = 0.91; I² = 0%), even if the patient had poor glycemic control (RR = 1.08, 95% CI 0.87–1.33; p = 0.48; I² = 70%). Meta-analysis of marginal bone loss in IL compared to conventional loading in DM2 patients also showed no significant difference (mean difference =  − 0.08, 95% CI − 0.25–0.08; p = 0.33; I² = 83%).

Conclusions

Type 2 diabetes mellitus does not seem to be a risk factor for immediately loaded implants if the glycemic level is controlled, the oral hygiene is satisfactory, and the technical steps are strictly followed.

Clinical relevance

Rehabilitation in diabetic individuals is more common due to the highest prevalence of edentulism in this population. It is essential to establish appropriate protocols for loading dental implants.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00784-021-04154-6.

Glycemic fluctuation exacerbates inflammation and bone loss and alters microbiota profile around implants in diabetic mice with experimental peri-implantitis

BACKGROUND

The impact of glycemic fluctuation under diabetic condition on peri-implantitis in diabetic patients remains unclear. We hypothesized that glycemic fluctuation has greater adverse effect on experimental peri-implantitis, compared with sustained high blood glucose in diabetes.

RESULTS

Maxillary left first and second molars of diabetic db/db mice were extracted and were replaced with one dental implant in the healed edentulous space. Glycemic control or fluctuation were managed by constant or interrupted oral administration of rosiglitazone to these mice. Meanwhile, experimental peri-implantitis was induced by ligation around implants. After 14 weeks, inflammatory responses, and peri-implant bone loss, together with oral microbiota profile were analyzed. Diabetic mice with glycemic fluctuation showed greater peri-implant bone loss, inflammatory cell infiltration, and osteoclastogenesis, compared with mice with sustained hyperglycemia. Compared to sustained hyperglycemia, glycemic fluctuation led to further increase in IL-1β, TNFα, RANKL, TLR2/4, IRAK1, and TRAF6 mRNA expression in peri-implant gingival tissues. Both rosiglitazone-induced glycemic control and glycemic fluctuation caused microbiota profile change in diabetic mice compared to that in uncontrolled hyperglycemic mice.

CONCLUSIONS

This study suggests that glycemic fluctuation may aggravate peri-implantitis inflammation and bone loss, which may be associated with a shift in peri-implant microbial profile towards dysbiotic changes and the activation of TLR2/4-IRAK1-TRAF6 signaling.

Pharmic Activation of PKG2 Alleviates Diabetes-Induced Osteoblast Dysfunction by Suppressing PLCβ1-Ca2+-Mediated Endoplasmic Reticulum Stress

As reported in our previous study, cinaciguat can improve implant osseointegration in type 2 diabetes mellitus (T2DM) rats by reactivating type 2 cGMP-dependent protein kinase (PKG2), but the downstream mechanisms remain unclear. In the present study, we investigated the favorable effect of cinaciguat on primary rat osteoblast, which was cultivated on titanium disc under vitro T2DM conditions (25 mM glucose and 200 μM palmitate), and clarified the therapeutic mechanism by proteomic analysis. The results demonstrated that T2DM medium caused significant downregulation of PKG2 and induced obvious osteoblast dysfunction. And overexpression of PKG2 by lentivirus and cinaciguat could promote cell proliferation, adhesion, and differentiation, leading to decreased osteoblasts injury. Besides, proteomic analysis revealed the interaction between PKG2 and phospholipase Cβ1 (PLCβ1) in the cinaciguat addition group, and we further verified that upregulated PKG2 by cinaciguat could inhibit the activation of PLCβ1, then relieve intracellular calcium overload, and suppress endoplasmic reticulum (ER) stress to ameliorate osteoblast functions under T2DM condition. Collectively, these findings provided the first detailed mechanisms responsible for cinaciguat provided a favorable effect on promoting osseointegration in T2DM and demonstrated a new insight that diabetes mellitus-induced the aberrations in PKG2-PLCβ1-Ca²⁺-ER stress pathway was one underlying mechanism for poor osseointegration.

Association between age-related macular degeneration and periodontal and peri-implant diseases: a systematic review

The aim of the present systematic review was to assess the association between age-related macular degeneration (AMD) and periodontal and peri-implant diseases. The focused question was 'Is there a relationship between AMD and periodontal and peri-implant diseases?' Indexed databases were searched up to and including May 2020 to identify pertinent original studies. The Cochrane Collaboration's tool was used to assess the risk of bias. Five observational cohort studies were included that assessed the association between AMD and periodontitis. The number of patients with and without AMD ranged between 54 and 90 and 1697 and 12,171 individuals, respectively. Examiner blinding to the study groups was performed in 1 of the 5 studies. None of the studies were power adjusted. Scrutiny of studies showed that all 5 studies included in the present systematic review had a high risk of bias. Results from all studies reported a direct association between AMD and periodontitis. No studies assessed the association between AMD and peri-implant diseases. The association between AMD and periodontal and peri-implant diseases remains debatable. Further well-designed and power-adjusted studies are needed to determine whether or not a 'true' association exists between AMD and periodontal and peri-implant diseases.

Covalent immobilization of the phytic acid-magnesium layer on titanium improves the osteogenic and antibacterial properties

In order to improve early osseointegration and long-term survival rate of implants, a multifunctional titanium surface that promotes osteogenesis and antibacterial properties is expected. Incorporation of bioactive trace elements such as magnesium ions was proved a promising method to improve osseointegration of titanium. Phytic acid has strong chelating ability with multivalent cations, which has been used in surface modification. Moreover, phytic acid was proved antibacterial potential. Herein, to improve the osteogenic and antibacterial properties, a phytic acid-magnesium (PA-Mg) layer was introduced on titanium using phytic acid as a cross-linker molecule. No obvious changes of the surface characterization were observed by scanning electron microscopy and atomic force microscopy. X-ray photoelectron spectroscopy confirmed that the PA-Mg layer covalently bond to the Ti surface, and the thickness of the PA-Mg layer was about 150 nm. Besides, improved hydrophilic and more protein adsorption were observed on Ti-PA-Mg. Notably, a relatively controlled magnesium release was also observed on Ti-PA-Mg. Human bone mesenchymal stem cells showed better adhesion, proliferation, and osteogenic differentiation on Ti-PA-Mg samples, indicating improved biocompatibility and osteoinductivity. Moreover, Ti-PA-Mg had better antibacterial properties against porphyromonas gingivalis than Ti. Overall, the PA-Mg layer on Ti surface improved the osteogenic and antibacterial properties, which may have promise for use in dental implantation.

A 5-year retrospective analysis of biologic and prosthetic complications associated with single-tooth endosseous dental implants: Practical applications

FOCUSED CLINICAL QUESTION

What are the key considerations of the incidence and timing for single-tooth implant complications, including early failure, biological complications, and prosthetic complications?

SUMMARY

Single-tooth dental implants have been shown to have a high overall survival rate, but implant complications affect patient satisfaction and may lead to costly and/or time-consuming repair and revision. Assessing the incidence and types of biologic and prosthetic complications and the timing of such complications is helpful so that the underlying causes can be addressed during the treatment planning process. Furthermore, identification of patient demographics, patient-, implant-, and site-specific factors associated with such complications may allow for more comprehensive risk assessment during treatment planning.

CONCLUSIONS

Overall, dental implants have a high survival rate. Identification of the incidence of both biologic and prosthetic complications and minimizing their impact in patients with dental implants is critical to overall implant success. Utilization of careful treatment planning and dental implant fixtures, surgical protocols, and prosthetic designs that reduce complication rates can improve patient acceptance and outcomes. Further research is necessary to fully assess complication rates and risk factors.

Bioadaptation of implants to In vitro and In vivo oxidative stress pathological conditions via nanotopography-induced FoxO1 signaling pathways to enhance Osteoimmunal regeneration

Varieties of pathological conditions, including diabetes, are closely related to oxidative stress (OS), but the osseointegration or bioadaptation of implants to OS and the related mechanism remain poorly explored. In this study, the antioxidation and osteoimmune regeneration of titanium implants with micro/nanotopographies were evaluated under H₂O₂-, lipopolysaccharide (LPS)- and hyperglycemia-mediated cellular OS models and in diabetic rats as a representative animal model of OS. TiO₂ nanotube (TNT) coating on titanium implants directly induced superior osteogenic differentiation of bone mesenchymal stem cells (MSCs) and osseointegration compared with microscale sand blasted-acid etched topography (SLA) under OS, attributed to higher superoxide dismutase 2 activity, the neutralization of intracellular reactive oxygen species (ROS), and less apoptosis. Mechanistically, the oxidation resistance on TNT is driven by upregulated forkhead box transcription factor O1 (FoxO1), which is abolished after knockdown of FoxO1 via shRNA in MSCs. Indirectly, TNT also alleviates OS in macrophages, therefore inducing a higher portion of the M2 phenotype under OS with increased secretion of the anti-inflammatory cytokine IL-10, further promoting the osseoimmunity capacity compared with SLA. The current study not only suggests the potential application of TiO₂ nanotube-coated titanium implants in compromised conditions but also provides a systematic evaluation strategy for the future development of bone biomaterials.

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H₂O₂, lipopolysaccharide and hyperglycemia induced cellular oxidative stress models.

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TiO₂ nanotubes promote oxidation resistance and osteogenesis under oxidative stress.

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TiO₂ nanotubes activate forkhead box transcription factor O1 to enhance osteogenesis.

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TiO₂-nanotube-coated implants promote osseointegration in diabetic rats.

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TiO₂ nanotubes induce anti-inflammatory osteoimmunity under oxidative stress.

Wearable biochemical sensors for human health monitoring: sensing materials and manufacturing technologies

Wearable biochemical sensors are of great interest nowadays due to their powerful potential in personalized medicine and continuous monitoring of human health. Thus, a great deal of effort has been put into the development of such sensors to enable real-time and non-invasive quantification of various chemical constituents in the human body such as sweat, saliva, and tears. Owing to the advances in materials science and mechanical engineering, wearable biochemical sensors have been developed to probe various biomarkers and have been subsequently considered as wearable electronic devices for practical applications. In this review, we present a broad overview on the recent advances in electrochemical wearable sensors towards various organic components and ions closely linked to human health. With an emphasis on materials and manufacturing technologies of the sensing electrodes, the research status is summarized, and the challenges and opportunities in this growing field are prospected.

Evaluation of the implant diameter on the initial-stability of narrow- and standard-diameter implants placed in simulated Type-I and Type-IV bone-blocks

Objective:

A comparison of the initial stability of narrow- and standard-diameter implants (SDIs) placed in Type-I and Type-IV bone-blocks is not yet reported. The aim was to evaluate in-vitro the influence of implant diameter on the initial stability of narrow- and standard-diameter implants (SDIs) placed in simulated Type-I and Type-IV bone-blocks.

Methods:

The present experimental in-vitro study was performed between July and September 2020 at the Specialist Dental Practice, Riyadh, Saudi Arabia. Narrow- and standard-diameter implants were placed 3-mm apart in simulated soft (Type-IV) and dense (Type-I) bone blocks by a trained and calibrated investigator. In groups A (Type-IV bone blocks) and B (Type-I bone blocks), implants were inserted using an insertion-torque and drilling-speed of 15-30 Ncm and 1000-1500 rpm, respectively with the implant collar at the crest of simulated bone blocks. In all samples, initial-stability was recorded using resonance frequency analysis (RFA). Sample-size estimation was done and group-comparisons were carried out. A P-value of 0.01 or less reflected statistical significance.

Results:

In Groups-A and -B, 44 (22 NDIs and 22 SDIs) and 44 (22 NDIs and 22 SDIs) were placed. In group-A, the mean RFA values for NDIs and SDIs were 68.5 ± 3.5 and 69.1 ± 2.4, respectively. In Group-B, the mean RFA values for NDIs and SDIs were 78.06 ± 9.6 and 75.3 ± 5.2. RFA values among NDIs and SDIs in groups A and B were similar.

Conclusion:

The NDIs and SDIs show comparable initial-stability when positioned in simulated Type-I and Type-IV bone blocks.

Influence of glycemic control on survival of zygomatic implants in relation with type-2 diabetes mellitus: 10 years' follow-up results

It is hypothesized that under optimal glycemic control (GC), there is no difference in the survival of implants placed in the zygomatic bone of edentulous patient with and without type-2 diabetes mellitus (T2DM). Purpose: The aim was to assess the influence of GC on survival of implants placed in the zygomatic bone of edentulous patient with and without T2DM at 10-years' follow-up. Twenty patients with T2DM (10 with poorly- and 10 with well-controlled T2DM) and 12 patients without T2DM were included. Hemoglobin A1c (HbA1c) levels were recorded and demographic data was collected from all participants. Peri-implant inflammatory parameters (plaque index [PI], probing depth [PD], crestal bone loss [BL] and gingival index [GI]) were measured in all patients. Group comparisons were done and P-values, which were less than 0.01 were indicative of statistical significance. Twenty and 12 male patients with and without T2DM, respectively were included. Among patients with T2DM, 10 and 10 individuals had poorly- and well-controlled T2DM, respectively.  The mean HbA1c levels were significantly higher in patients with poorly- (9.2 ± 0.7%) compared with well-controlled T2DM (4.8 ± 0.3%) (P<0.01) and non-diabetic individuals (4.6 ± 0.3%) (P<0.01). The crestal BL on the mesial (P<0.01) and distal (P<0.01) surfaces, PD (P<0.01), PI (P<0.01), and GI (P<0.01) were significantly higher around all zygoma implants placed in patients with poorly-controlled T2DM compared with patients with well-controlled T2DM and patients without T2DM. These clinicoradiographic parameters were comparable around zygoma implants placed in patient with well-controlled T2DM and in subjects without T2DM.  Optimal glycemic control is essential for the long-term stability of zygomatic plants in patients with T2DM.

Role of probiotics for the treatment of peri-implant mucositis in patients with and without type-2 diabetes mellitus

The hypothesis was that probiotic therapy (PT) does not offer additional benefits to mechanical debridement (MD) for treatment of diabetic subjects with peri-implant mucositis (PM). This study compared the influence of PT as an adjunct to MD for the treatment of PM in type2 diabetic and non-diabetic patients over a 12-month follow-up period. Patients with and without type-2 diabetes were encompassed. Based upon treatment-procedure, PM patients were categorized into 2 groups: (a) Non-surgical + PT; and (b) Group-2: Non-surgical MD alone. Demographics and education statuses were recorded. Gingival (GI) and plaque (PI) indices, crestal bone loss (CBL) and probing depth (PD were measured at baseline and after 6- and 12-months. Significant differences were detected with P<0.01. The HbA1c was significantly higher in diabetic patients at all time durations than patients without type-2 diabetes (P<0.001). Baseline GI, PI, PD and CBL) were comparable in all groups. In patients with type-2-diabetes, there was no difference in PI, GI, PD and CBL at 6- and 12-months' follow-up. In patients without type-2 diabetes, there was a significant reduction in PI (P<0.01), GI (P<0.01), and PD (P<0.01) at 6-months and 1-year follow-up than their values at baseline. In patients without type-2 diabetes, MD with or without adjunct PT reduces soft tissue inflammatory parameters in patients with PM.

Effectiveness of single versus multiple sessions of photodynamic therapy as adjunct to scaling and root planing on periodontopathogenic bacteria in patients with periodontitis

OBJECTIVE

The aim of the present 6-months' follow-up study was to assess the influence of single versus multiple sessions of photodynamic therapy (PDT) as adjunct to scaling and root planning (SRP) on periodontopathogenic bacteria in patients with periodontitis.

METHODS

Forty-five patients with periodontitis were included. The patients were randomly divided into 3 groups. In groups 1 (n = 15), 2 (n = 15) and 3 (n = 15), the patients under went SRP with PDT at (a) baseline; (b) baseline and after 1-month; and (c) baseline and after 1- and 3-months. Peri-implant plaque index (PI), bleeding on probing (BOP), probing depth (PD), clinical attachment loss (CAL) and marginal bone loss (MBL) were measured at baseline and 6-months follow-up. Counts of Porphyromonas gingivalis, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum and Aggregatibacter Actinomycetemcomitans were determined before SRP and at 4- and 6-months follow-up.

RESULTS

All patients had grade-B periodontitis. There was no statistically significant difference in age and gender in all groups. At- 6-months' follow-up, patients that underwent SRP once showed significantly higher counts of periodontopathogenic bacteria in the oral biofilm compared with patients that received photobiomodulation twice or three times (P < 0.05). There was no significant difference in the periodontal parameters and counts of gram-negative bacteria in patients that received photobiomodulation 2 or 3 times.

CONCLUSION

At least 2 sessions of PDT following baseline SRP is essential to achieve a significant reduction in the counts of subgingival bacteria in periodontitis patients over a 6-month follow-up period.

Comparison of peri-implant soft tissue and crestal bone status of dental implants placed in prediabetic, type 2 diabetic, and non-diabetic individuals: a retrospective cohort study

Background

Clinicoradiographic status of narrow-diameter implants (NDIs) among patients with prediabetes and type 2 diabetes mellitus (DM) is scarce. The aim was to address the clinicoradiographic status of NDIs placed prediabetic, type 2 diabetic, and non-diabetic individuals. In this retrospective cohort study, patients having undergone oral rehabilitation with NDI were included. The participants were divided into the following: (a) patients with prediabetes; (b) patients with poorly controlled type 2 DM; (c) patients with well-controlled type 2 DM; and (d) normoglycemic individuals. Demographic data was collected. In all groups, peri-implant plaque index (PI), gingival index (GI), probing depth (PD), and mesiodistal CBL were measured in all groups. Information related to implant dimensions, surface characteristics, insertion torque, implant geometry, duration of NDI in function, and jaw location of NDI was also recorded. Data normality was assessed and group comparisons were performed. A probability value under 0.01 was considered statistically significant.

Results

Eighty-three patients (20 patients had prediabetes, 22 with poorly controlled type 2 DM, 20 with well-controlled type 2 DM, and 20 self-reported non-diabetic individuals) were included. The mean HbA1c levels were significantly higher among patients with prediabetes (P < 0.01) and poorly controlled type 2 DM (P < 0.01) than patients with well-controlled type 2 DM and non-diabetic controls. Peri-implant PI, GI, PD, and mesiodistal CBL levels were significantly higher among patients with pre-diabetes (P < 0.01) and poorly controlled type 2 DM (P < 0.01) than patients with well-controlled type 2 DM and non-diabetic controls. Peri-implant PI, GI, PD, and mesiodistal CBL levels were significantly higher among patients with poorly controlled type 2 DM (P < 0.01) than patients with prediabetes.

Conclusion

Chronic hyperglycemia increases the risk of peri-implant diseases around NDIs.

Efficacy of Nonsurgical Mechanical Debridement With and Without Adjunct Low-Level Laser Therapy in the Treatment of Peri-Implantitis: A Randomized Controlled Trial

We hypothesized that in the long term (6-month follow-up), nonsurgical mechanical debridement (NSMD) with adjunct low-level laser therapy (LLLT) is more effective for the treatment of peri-implantitis than NSMD alone. The aim of the present 6-month follow-up convenience-sample cohort study was to assess the efficacy of LLLT as an adjunct to NSMD in the treatment of peri-implantitis. A questionnaire was used to collect demographic information. Patients with peri-implantitis in the test and control groups underwent NSMD with and without adjunct LLLT, respectively. Randomization was done by tossing a coin. In the test group, the laser was applied perpendicular to the periodontal pocket for 20 seconds at a constant distance of 15 mm and with a continuous wavelength (3.41 J/cm2 delivery with a 1.76 cm2 spot and average output of 0.3 W). In both groups, peri-implant probing depth, bleeding upon probing, and crestal bone resorption were assessed at baseline and at the 3-month and 6-month follow-up. Group comparisons were performed, and P < .05 was considered statistically significant. Sixty-seven individuals with peri-implantitis were included. The mean age of participants who underwent NSMD with adjunct LLLT and NSMD alone was 46.5 ± 3.4 and 45.3 ± 1.1 years, respectively. At the 3- and 6-month follow-up, peri-implant (P < .05), bleeding upon probing (P < .05), and probing depth (P < .05) were significantly higher among patients who underwent NSMD alone compared with patients who underwent NSMD with adjunct LLLT. There was no significant difference in crestal bone resorption in all patients up to the 6-month follow-up. In the short term, NSMD with adjunct LLLT was a useful treatment protocol for the treatment of peri-implant soft-tissue inflammation.

Clinical Decision Making for Primary Peri-Implantitis Prevention: Practical Applications

FOCUSED CLINICAL QUESTION

When planning dental implant therapy, what risk-reduction strategies allow practitioners to select patients, sites, and restorative plans that decrease the incidence of peri-implant disease?

SUMMARY

With a marked increase in the number of patients receiving dental implants to treat partial or complete edentulism, it follows that the prevalence of peri-implant mucositis and peri-implantitis have increased. Risks associated with implant therapies may vary based upon underlying local, environmental, surgical, patient, prosthetic, and fixture-related factors. Furthermore, an emphasis on preventative measures and maintenance should be undertaken to avoid development and progression of peri-implant diseases. Thorough risk assessment, proper treatment planning, and early diagnosis and intervention are critical in the absence of definitive data of long-term success of treatments for peri-implant condition. Given the difficulty in intervention once peri-implantitis is established, identification of risk factors and development of treatment plans to address those factors before dental implant therapy is critical to the long-term health and success of dental implants.

CONCLUSIONS

A patient-centered, evidence based approach to dental implant treatment planning to reduce the risk for peri-implantitis should be undertaken. Systematic diagnosis of disease state(s) and evaluation of the etiologic and modifying risk factors for peri-implant diseases can yield more optimal outcomes to reduce peri-implantitis rates.

Prevalence of Peri-Implantitis: A Multi-Centered Cross-Sectional Study on 248 Patients

The aim of this multicenter cross-sectional study was to determine the prevalence of peri-implantitis and to assess its association with several patient- and implant-related factors. Patients with at least one implant, who came for a recall visit to one of the four centers over a period of five months, were enrolled. Presence of peri-implantitis (defined as bleeding on probing, exudate/suppuration, bone loss > 0.2 mm/year and increased pocket depth) and several other variables (e.g., smoking habits, history of periodontitis, diabetes) were recorded. Out of 248 enrolled patients (1162 implants), 10 patients had at least one implant with peri-implantitis (4.03%); a total of 14 implants were affected (1.20%). A statistically significant association between peri-implantitis and diabetes was found (OR 8.65; CI: 1.94–38.57). Smoking more than 10 cigarettes per day (OR: 0.53; CI 0.03–9.45) and history of periodontitis (OR: 2.42; CI: 0.49–11.89) were not found to be statistically associated with peri-implantitis. Even if implant therapy is a consolidated treatment, biological complications do happen. Strict supportive therapy recalls could lead to lower rates of peri-implantitis and earlier diagnosis.

Radiographic bone level around particular laser-treated dental implants: 1 to 6 years multicenter retrospective study

Purpose

The aim of the present retrospective study was to evaluate clinical and radiological outcomes, in terms of implant survival rate, marginal bone loss, and peri-implantitis incidence, of a titanium implants with an innovative laser-treated surface.

Materials and methods

A total of 502 dental implants were inserted in four dental practices (Udine, Arezzo, Frascati, Roma) between 2008 and 2013. All inserted implants had laser-modified surface characterized by a series of 20-μm-diameter holes (7–10 μm deep) every 10 μm (Synthegra®, Geass srl, Italy). The minimum follow-up period was set at 1 year after the final restoration. Radiographs were taken after implant insertion (T0), at time of loading (T1), and during the follow-up period (last recall, T2). Marginal bone loss and peri-implant disease incidence were recorded.

Results

A total of 502 implants with a maximum follow-up period of 6 years were monitored. The mean differential between T0 and T2 was 0.05 ± 1.08 mm at the mesial aspect and 0.08 ± 1.11 mm at the distal with a mean follow-up period of 35.76 ± 18.05 months. After being in function for 1 to 6 years, implants reported varying behavior: 8.8% of sites did not show any radiographic changes and 38.5% of sites showed bone resorption. The bone appeared to have been growing coronally in 50.7% of the sites measured.

Conclusion

Implants showed a maintenance of marginal bone levels over time, and in many cases, it seems that laser-modified implant surface could promote a bone growth. The low peri-implant disease incidence recorded could be attributed to the laser titanium surface features that seem to prevent bacterial colonization. Future randomized and controlled studies are needed to confirm the results of the present multi-centrical retrospective analysis.

Primary stability of narrow-diameter dental implants with a multiple condensing thread design placed in bone with and without osteotomes: An in vitro study

BACKGROUND

The authors hypothesized that there is no difference in the primary stability (PS) of multiple condensing thread design (MCTD) implants placed in simulated type-IV bone with and without using osteotomes.

PURPOSE

This in vitro study assessed the PS of narrow-diameter dental implants with MCTD placed in simulated soft (type-IV) bone with and without using osteotomes.

MATERIALS AND METHODS

Sixty MCT-designed implants (diameter: 3.0 mm; length: 11.5 mm) were placed using 800 rpm drilling speed in cellular rigid polyurethane foam bone-blocks that simulated type-IV bone. Prior to placement, the implants were divided into three groups (20 implants per group) depending upon the protocol used for osteotomy preparation-Group-1: Conventional drilling (CD); Group-2: CD followed by osseous condensation using a chisel-shaped tapered osteotome with maximum diameter of 3 mm; and Group-3: CD followed by osseous condensation using a cylindrical osteotome with maximum diameter of 3 mm. Abutments were connected to all implants and PS was recorded using resonance frequency analysis (RFA) and the periotest (PTV). Group comparisons were performed using analysis and Bonferroni post-hoc adjustment tests. Level of significance was set at P < .05.

RESULTS

There was no statistically significant difference in the RFA values for the MCT-designed implants placed in groups 1, 2, and 3 (59.85 ± 0.72, 59.67 ± 0.76 and 59.42 ± 0.92, respectively). There was no statistically significant difference in the PTV values for MCT-designed implants in groups 1, 2, and 3 (1.655 ± 0.82, 1.405 ± 0.57, and 1.078 ± 0.63, respectively).

CONCLUSION

The MCTD implants with narrow diameters have a high PS in artificial soft bone in vitro. Due to the condensation effect of the thread design, there is no need for additional condensation of the peri-osteotomy bone in order to improve implant stability.

PTH Derivative promotes wound healing via synergistic multicellular stimulating and exosomal activities

BACKGROUND

Diabetic wounds are a disturbing and rapidly growing clinical problem. A novel peptide, parathyroid hormone related peptide (PTHrP-2), is assumed as multifunctional factor in angiogenesis, fibrogenesis and re-epithelization. This study aims to test PTHrP-2 efficiency and mechanism in wound healing.

METHODS

Through repair phenomenon in vivo some problems were detected, and further research on their mechanisms was made. In vivo therapeutic effects of PTHrP-2 were determined by HE, Masson, microfil and immunohistochemical staining. In vitro direct effects of PTHrP-2 were determined by proliferation, migration, Vascular Endothelial Grown Factor and collagen I secretion of cells and Akt/ Erk1/2 pathway change. In vitro indirect effects of PTHrP-2 was study via exosomes. Exosomes from PTHrP-2 untreated and treated HUVECs and HFF-1 cells were insolated and identified. Exosomes were co-cultured with original cells, HUVECs or HFF-1 cells, and epithelial cells. Proliferation and migration and pathway change were observed. PTHrP-2-HUVEC-Exos were added into in vivo wound to testify its hub role in PTHrP-2 indirect effects in wound healing.

RESULTS

In vivo, PTHrP-2 exerted multifunctional pro-angiogenesis, pro-firbogenesis and re-epithelization effects. In vitro, PTHrP-2 promoted proliferation and migration of endothelial and fibroblast cells, but had no effect on epithelial cells. Therefore, we tested PTHrP-2 indirect effects via exosomes. PTHrP-2 intensified intercellular communication between endothelial cells and fibroblasts and initiated endothelial-epithelial intercellular communication. PTHrP-2-HUVEC-Exos played a hub role in PTHrP-2 indirect effects in wound healing.

CONCLUSION

These findings of this study indicated that PTHrP-2, a multifunctional factor, could promote wound healing via synergistic multicellular stimulating and exosomal activities.

Concepts for prevention of complications in implant therapy

The use of dental implants is nowadays a well-accepted and highly predictable treatment modality for restoring the dentition and reestablishing the masticatory function of edentulous and partially edentulous patients. Despite the high predictability and excellent long-term survival rates reported for implant therapy, complications may still occur and can jeopardize both short- and long-term success. The present paper provides an overview on the most important aspects related to the etiology, prevention, and management of complications associated with implant therapy. Data from the literature indicate that a number of factors, such as surgical trauma, implant diameter, type of implant-abutment connection, abutment disconnection and reconnection, presence of microgap, and implant malpositioning, can substantially influence the biologic processes of bone remodeling and biofilm formation, thus increasing the rate of short- and long-term hard- and soft-tissue complications. Other factors, such as excess cement at cement-retained prosthetic restorations, abutment mobility, and infections (e.g. peri-implant mucositis and peri-implantitis) caused by bacterial biofilm, are further causes for complications and failures. More recent evidence also indicates that besides the need for sufficient bone volume surrounding the implant, the presence of an adequate width and thickness of attached mucosa may improve biofilm control and limit crestal bone resorption. Furthermore, emerging evidence points also to the pivotal role of human factors as one of the most important causes of complications in implant dentistry. It can be concluded that clinicians need to consider all biologic and biomechanical factors affecting implant placement and survival, as well as undergo adequate training to improve their surgical skills to control and prevent implant complications. Careful patient selection and control of environmental and systemic factors, such as smoking, diabetes etc., coupled with an accurate surgical and prosthetic planning, enable a better prevention and control of infections.