Alveolar bone loss is a significant contributor to tooth loss in dentate HIV+ patients: A retrospective study

BACKGROUND

The study objectives were to determine tooth loss prevalence and to investigate the relationship between tooth loss and potential risk factors among adult dentate HIV+ patients on newer antiretroviral therapy (ART) regimens.

METHODS

Health records of 450 human immunodeficiency virus (HIV)-infected individuals were surveyed. Eighty-eight records of dentate HIV+ individuals with full-mouth periodontal charting and intra-oral periapical radiographs were identified. We collected data on demographics, systemic risk factors, oral health, and HIV disease measures. Caries exposure and alveolar bone loss (ABL) were radiographically assessed.

RESULTS

Eighty-eight percent of patients showed tooth loss. Patients with ABL ≥15% had a higher number of missing teeth (p < .01). Stepwise regression analyses indicated that tooth loss was positively associated with age (β = 0.45, p < .01) and ABL (β = 0.39, p < .01). By contrast number of years on ART was negatively associated with tooth loss (β = -0.28, p < .05).

CONCLUSIONS

Tooth loss remains prevalent among HIV+ patients, and periodontal disease is a significant contributor. The number of years on ART seem to improve oral health behavior and reduce tooth loss.

Essential genes for Haemophilus parainfluenzae survival and biofilm growth

Haemophilus parainfluenzae (Hp) is a Gram-negative, highly prevalent, and abundant commensal in the human oral cavity, and an infrequent extraoral opportunistic pathogen. Hp occupies multiple niches in the oral cavity, including the supragingival plaque biofilm. Little is known about how Hp interacts with its neighbors in healthy biofilms nor its mechanisms of pathogenesis as an opportunistic pathogen. To address this, we identified the essential genome and conditionally essential genes in in vitro biofilms aerobically and anaerobically. Using transposon insertion sequencing (TnSeq) with a highly saturated mariner transposon library in two strains, the ATCC33392 type-strain (Hp 392) and oral isolate EL1 (Hp EL1), we show that the essential genomes of Hp 392 and Hp EL1 are composed of 395 (20%) and 384 (19%) genes, respectively. The core essential genome, consisting of 341 (17%) essential genes conserved between both strains, was composed of genes associated with genetic information processing, carbohydrate, protein, and energy metabolism. We also identified conditionally essential genes for aerobic and anaerobic biofilm growth, which were associated with carbohydrate and energy metabolism in both strains. RNAseq analysis determined that most genes upregulated during anaerobic growth are not essential for Hp 392 anaerobic survival. The completion of this library and analysis under these conditions gives us a foundational insight into the basic biology of H. parainfluenzae in differing oxygen conditions, similar to its in vivo habitat. This library presents a valuable tool for investigation into conditionally essential genes for an organism that lives in close contact with many microbial species in the human oral habitat.IMPORTANCEHaemophilus parainfluenzae is a highly abundant human commensal microbe, present in most healthy individuals where it colonizes the mouth. H. parainfluenzae correlates with good oral health and may play a role in preservation of healthy host status. Also, H. parainfluenzae can cause opportunistic infections outside of the oral cavity. To date, little is known about how H. parainfluenzae colonizes the human host, despite being such a frequent and abundant part of our human microbiome. Here, we demonstrate the creation and use of a powerful tool, a TnSeq library, used to identify genes necessary for both the outright growth of this organism and also genes conditionally essential for growth in varying oxygen status which it can encounter in the human host. This tool and these data serve as a foundation for further study of this relatively unknown organism that may play a role in preserving human health.

Evaluation and comparison of autologous particulate dentin with demineralized freeze dried bone allograft in ridge preservation procedures - a prospective clinical study

OBJECTIVES

To compare effectiveness of Autologous Particulate Dentin (APD) with Demineralized Freeze-Dried Bone Allograft (DFDBA) in ridge preservation, using radiographic and clinical parameters.

MATERIALS AND METHODS

Thirty subjects with indication of mandibular posterior teeth extraction were randomly assigned to either test or control group. After atraumatic extraction, ridge preservation was performed using APD or DFDBA mixed with i-PRF in test and control groups respectively. Both groups had sockets sealed with A-PRF membrane. Clinical parameters (plaque, gingival and healing indices) and radiographic parameters (vertical ridge height, horizontal ridge width) were assessed at baseline and 6 months using CBCT. Statistical analysis was performed using an independent t-test to compare clinical and radiographic parameters between the groups.

RESULTS

Both groups had significant decreases in ridge dimensions over 6 months (p < 0.001). The test group showed less reduction in ridge dimensions than control group at 6 months (p < 0.001). Mean change in vertical height was not significant (1.37 ± 1.32, 1.7311 ± 0.563), but in horizontal ridge width (1.3120 ± 1.13, 1.8093 ± 1.16) was significantly different between test and control groups respectively. There was no statistical difference in clinical parameters between the groups at 6 months (p > 0.001).

CONCLUSIONS

APD grafts resulted in significant improvements in radiographic parameters, specifically in vertical ridge height and horizontal ridge width, compared to DFDBA group.

CLINICAL RELEVANCE

Autologous particulate dentin is a promising, versatile substitute for regenerative procedures. While more research on its long-term efficacy and application is needed, current evidence suggests it could significantly improve patient care and outcomes.

Invasion of human dental pulp fibroblasts by Porphyromonas gingivalis leads to autophagy via the phosphoinositide 3-kinase/Akt/mammalian target of rapamycin signaling pathway

OBJECTIVES

Porphyromonas gingivalis is a pathogenic bacterium that causes periodontitis and dental pulp infection. Autophagy is a potential mechanism involved in inflammatory disease. This study established an in vitro model of P. gingivalis intracellular infection in human dental pulp fibroblasts (HDPFs) to investigate the effects of live P. gingivalis on HDPFs.

METHODS

Morphological and quantification techniques such as fluorescence microscopy, transmission electron microscopy (TEM), indirect immunofluorescence analysis, enzyme-linked immunosorbent assay (ELISA), real-time polymerase chain reaction (PCR), and western blotting were used in this study.

RESULTS

After cell invasion, P. gingivalis is mainly localized in the cytoplasm and lysosomes. Additionally, P. gingivalis activates autophagy in HDPFs by upregulating the expression of autophagy-related gene Beclin-1, activate autophagy-related gene12 (ATG12), and microtubule-associated protein light chain 3 (LC3). Furthermore, the invasion of P. gingivalis leads to increased phosphorylation of PI3K, Akt, and mTOR with the addition of rapamycin, whereas the addition of wortmannin decreased phosphorylation. This invasion of P. gingivalis, also causes an inflammatory response, leading to the upregulation of IL-1β, IL-6, and TNF-α. Rapamycin helps decrease levels of pro-inflammatory cytokines, but the addition of wortmannin increases them. These results show that the invasion of P. gingivalis can cause excessive inflammation and promote the autophagy of HDPFs, which is regulated by PI3K/Akt/mTOR.

CONCLUSIONS

P. gingivalis escapes the immune system by inducing autophagy in the host cells, causing excessive inflammation. P. gingivalis regulates autophagy in HDPFs through the phosphoinositide 3-kinase/Akt/mammalian target of rapamycin pathway.

Higher solubility and lower onset temperature of protein denaturation increase the osteoconductive capacity of collagen membranes: A preclinical in vivo study

OBJECTIVES

Collagen membranes are extensively used for guided bone regeneration procedures, primarily for horizontal bone augmentation. More recently, it has been demonstrated that collagen membranes promote bone regeneration. Present study aimed at assessing if structural modifications of collagen membranes may enhance their osteoconductive capacity.

METHODS

Twenty-four adult Wistar rats were used. Bilateral calvaria defects with a diameter of 5 mm were prepared and covered with prototypes of collagen membranes (P1 or P2). The P1 membrane (positive control) presented a lower onset temperature of protein denaturation and a higher solubility than the P2 membrane (test). The contralateral defects were left uncovered (NC). After 1 and 4 weeks, the animals were euthanized. A microcomputed tomography analysis of the harvested samples was performed within and above the bony defect. Undecalcified ground sections were subjected to light microscopy and morphometric analysis.

RESULTS

Bone formation was observed starting from the circumferential borders of the defects in all groups at 1-week of healing. The foci of ossification were observed at the periosteal and dura mater sites, with signs of collagen membrane mineralization. However, there was no statistically significant difference between the groups. At 4 weeks, remnants of the collagen fibers were embedded in the newly formed bone. In the P2 group, significantly more bone volume, more new bone, and marrow spaces compared to the NC group were observed. Furthermore, the P2 group showed more bone volume ectocranially then the P1 group.

CONCLUSIONS

Bone formation subjacent to a P2 membrane was superior than subjacent to the P1 membrane and significantly better compared to the control. Modifications of the physico-chemical properties may enhance the osteoconductive competence of collagen membranes, supporting bone formation outside the bony defects.

Evidence of an effect of statins on lesions originating from dental infection. A retrospective clinical investigation

BACKGROUND

Apical periodontitis (AP) is an inflammatory dental disease caused by bacterial infections of the endodontic system. The correlation between AP and cardiovascular diseases. (CVD) has been consistently investigated. Statins are a class of drugs that are used to treat hypercholesterolemia and prevent atherosclerotic vascular diseases. They have other beneficial pleiotropic effects such as anti-inflammatory, antithrombotic, and antioxidant activities. The aim of this study was to evaluate the oral health status and prevalence of AP in patients treated with statins (Group S) in comparison with untreated patients (Group C) to understand whether the anti-inflammatory action of these drugs can influence the prevalence of AP.

METHODS

The records of seventy-nine patients (43 men and 36 women, mean age 68 ± 11 years, 1716 teeth) treated with statins and referred to the University clinic for dental evaluation were reviewed. Seventy patients free from systemic diseases and without therapy (39 men and 31 women, mean age 62 ± 9 years, 1720 teeth) constituted the control group. All subjects underwent complete oral, dental, and radiographic examinations to determine the presence and severity of AP. Periapical index (PAI) and decayed, missed, and filled teeth (DMFT) scores were obtained.

RESULTS

AP was significantly less common in Group S (22,8%) than in Group C (50%) (P < 0.05). Furthermore, the mean value of the qualitative rank of the severity of AP (PAI score) was higher in Group C than in Group S (P ≤ 0.05).

CONCLUSIONS

Our results suggest that statins can attenuate the prevalence of AP, which is associated to CVD.

Biomaterial Scaffolds for Periodontal Tissue Engineering

Advanced periodontitis poses a significant threat to oral health, causing extensive damage and loss of both hard and soft periodontal tissues. While traditional therapies such as scaling and root planing can effectively halt the disease's progression, they often fail to fully restore the original architecture and function of periodontal tissues due to the limited capacity for spontaneous regeneration. To address this challenge, periodontal tissue engineering has emerged as a promising approach. This technology centers on the utilization of biomaterial scaffolds, which function as three-dimensional (3D) templates or frameworks, supporting and guiding the regeneration of periodontal tissues, including the periodontal ligament, cementum, alveolar bone, and gingival tissue. These scaffolds mimic the extracellular matrix (ECM) of native periodontal tissues, aiming to foster cell attachment, proliferation, differentiation, and, ultimately, the formation of new, functional periodontal structures. Despite the inherent challenges associated with preclinical testing, the intensification of research on biomaterial scaffolds, coupled with the continuous advancement of fabrication technology, leads us to anticipate a significant expansion in their application for periodontal tissue regeneration. This review comprehensively covers the recent advancements in biomaterial scaffolds engineered specifically for periodontal tissue regeneration, aiming to provide insights into the current state of the field and potential directions for future research.

Toll-like receptor 4 deficiency affects the balance of osteoclastogenesis and osteoblastogenesis in periodontitis

Toll-like receptor 4 (TLR4) acts as a double-edged sword in the occurrence and development of periodontitis. While the activation of TLR4 in macrophages aids in clearing local pathogens, it can also disrupt innate immune responses, upsetting microecological balance and accelerating the destruction of periodontal bone tissues. To date, the effects of TLR4 on osteogenesis and osteoclastogenesis in periodontitis have not been comprehensively studied. In this study, we investigated the development of periodontitis in the Tlr4-/- mice by ligating their second molars with silk threads. Compared to wild-type (WT) mice, Tlr4-/- mice demonstrated increased resistance to periodontitis-associated bone destruction, as evidenced by decreased bone resorption and enhanced bone regeneration. Mechanistically, the deletion of Tlr4 not only inhibited osteoclast formation by reducing the expression of NFATc1, CTSK and TRAP, but also enhanced osteogenic abilities through increased expression of OCN, OPN and RUNX2. In conclusion, TLR4 tips the balance of osteoclastogenesis and osteogenesis, thereby promoting periodontal bone destruction in periodontitis.

Consideration of hormonal changes for orthodontic treatment during pregnancy and lactation - a review

Hormonal changes in pregnant and lactating women significantly affect bone metabolism and overall stress levels, positioning them as a unique group within the orthodontic population. Fluctuations in estrogen, progesterone, prolactin, and other hormones are closely linked to bone remodeling and the periodontal tissue's response to inflammation caused by dental plaque. Hormones such as thyrotropin, leptin, and melatonin also play crucial roles in pregnancy and bone remodeling, with potential implications for orthodontic tooth movement. Additionally, adverse personal behaviors and changes in dietary habits worsen periodontal conditions and complicate periodontal maintenance during orthodontic treatment. Notably, applying orthodontic force during pregnancy and lactation may trigger stress responses in the endocrine system, altering hormone levels. However, these changes do not appear to adversely affect the mother or fetus. This review comprehensively examines the interaction between hormone levels and orthodontic tooth movement in pregnant and lactating women, offering insights to guide clinical practice.

Targeted Reprogramming of Pathogenic Fibroblast Genes at the 3'-Untranslated Regions by DNA Nanorobots for Periodontitis

Periodontitis, with its persistent nature, causes significant distress for most sufferers. Current treatments, such as mechanical cleaning and surgery, often fail to fully address the underlying overactivation of fibroblasts that drives this degradation. Targeting the post-transcriptional regulation of fibroblasts, particularly at the 3'-untranslated regions (3'UTR) of pathogenic genes, offers a therapeutic strategy for periodontitis. Herein, we developed a DNA nanorobot for this purpose. This system uses a dynamic DNA nanoframework to incorporate therapeutic microRNAs through molecular recognition and covalent bonds, facilitated by DNA monomers modified with disulfide bonds. The assembled-DNA nanoframework is encapsulated in a cell membrane embedded with a fibroblast-targeting peptide. By analyzing the 3'UTR regions of pathogenic fibroblast genes FOSB and JUND, we identified the therapeutic microRNA as miR-1-3p and integrated it into this system. As expected, the DNA nanorobot delivered the internal components to fibroblasts by the targeting peptide and outer membrane that responsively releases miR-1-3p under intracellular glutathione. It resulted in a precise reduction of mRNA and suppression of protein function in pathogenic genes, effectively reprogramming fibroblast behavior. Our results confirm that this approach not only mitigates the inflammation but also promotes tissue regeneration in periodontal models, offering a promising therapeutic avenue for periodontitis.

Centrifugal Microfluidic Cell Culture Platform for Physiologically Relevant Virus Infection Studies: A Case Study with HSV-1 Infection of Periodontal Cells

Static well plates remain the gold standard to study viral infections in vitro, but they cannot accurately mimic dynamic viral infections as they occur in the human body. Therefore, we established a dynamic cell culture platform, based on centrifugal microfluidics, to study viral infections in perfusion. To do so, we used human primary periodontal dental ligament (PDL) cells and herpes simplex virus-1 (HSV-1) as a case study. By microscopy, we confirmed that the PDL cells efficiently attached and grew in the chip. Successful dynamic viral infection of perfused PDL cells was monitored using fluorescent imaging and RT-qPCR-based experiments. Remarkably, viral infection in flow resulted in a gradient of HSV-1-infected cells gradually decreasing from the cell culture chamber entrance towards its end. The perfusion of acyclovir in the chip prevented HSV-1 spreading, demonstrating the usefulness of such a platform for monitoring the effects of antiviral drugs. In addition, the innate antiviral response of PDL cells, measured by interferon gene expression, increased significantly over time in conventional static conditions compared to the perfusion model. These results provide evidence suggesting that dynamic viral infections differ from conventional static infections, which highlights the need for more physiologically relevant in vitro models to study viral infections.

Engaging vs. Non-Engaging Abutments: An In Vitro Study Evaluating Changes in Microgap and Screw Morphology

BACKGROUND

The purpose of this study was to compare the microgap size between engaging (E) and non-engaging (NE) abutments and screw morphology changes between E and NE abutments using scanning electron microscopy (SEM) before and after cyclic loading (CL).

METHODS

Thirty-six implants were arranged into four groups as follows: Group 1, single units with E abutments; Group 2, single units with NE abutments; Group 3, three-unit fixed partial dentures with a hemi-engaging design; and Group 4, three-unit FPDs with two NE abutments. The microgap was evaluated using a stereomicroscope. SEM was used to qualitatively evaluate screw morphology. The specimens were subjected to axial loading first and then lateral loading (30°) using the settings; one million cycles (1.0 × 106 cycles) for each loading axis.

RESULTS

There were no significant differences detected in the microgap sizes between the E and NE abutment groups. In addition, there were no significant changes in the microgap sizes after CL in the E or NE abutment specimens. More damage to the screws was noticed after CL compared to before, with no difference in the patterns of damage detected between the E and NE abutments.

CONCLUSIONS

No significant difference in microgap size was detected between the E and NE abutments. Furthermore, there was no significant difference in microgap size between the different prosthetic designs. From the SEM qualitative evaluation, there were similar screw morphology changes after CL between the E and NE abutments.

Association Between Periodontal Diseases and Hypothyroidism: A Case-Control Study

Objective

Periodontal diseases are chronic inflammatory disorders influenced by systemic health of the individual. This study aimed to investigate the association between hypothyroidism and periodontal disease in a cohort of adult Saudi population.

Methods

This case-control study included 201 adults with hypothyroidism on hormone replacement therapy and 188 healthy controls. The medical files of patients were reviewed to check thyroid stimulation hormone (TSH) and free thyroxine (FT4) levels. Participants completed a questionnaire on demographic and health information, followed by a comprehensive periodontal examination. Pearson chi-square and binary logistic regression analyses determined associations, with a significance set at p ≤0.05.

Results

Gingivitis was found in 20.9% of cases and 58% of controls. Periodontitis stages I, II, III and IV were in general higher in cases compared to controls (23.4%, 27.9%, 21.9%, 6% in cases versus 13.8%, 17%, 9.6%, 1.6% in controls, respectively). Mean PPD and CAL values were higher in cases (5.54 ± 2.5 and 3.88 ± 3.1) than in controls (4.03 ± 1.6 and 1.72 ± 2.4). Significant associations between periodontal status and hypothyroidism were found (p < 0.0001). The periodontal status in hypothyroid cases correlated significantly with hormone replacement therapy dose and duration (p < 0.0001).

Conclusion

The findings of the current study showed that, in a cohort of adult Saudi subjects, patients with hypothyroidism have higher prevalence and more severe periodontal disease symptoms compared to controls, suggesting significant association.

Human Umbilical Cord Mesenchymal Stem Cells-Derived Extracellular Vesicles for Rat Jawbone Regeneration in Periapical Periodontitis

Extracellular vesicles derived from mesenchymal stem cells (MSCs-EVs) have great potential for bone remodeling and anti-inflammatory therapy. For the repair and reconstruction of inflammatory jawbone defects caused by periapical periodontitis, bone meal filling after debridement is commonly used in the clinic. However, this treatment has disadvantages such as large individual differences and the need for surgical operation. Therefore, it is of great significance to search for other bioactive substances that can promote jawbone regeneration in periapical periodontitis. Herein, it is found that CT results showed that local injection of human umbilical cord mesenchymal stem cells-derived extracellular vesicles (HUC-MSCs-EVs) and bone meal filling into the alveolar bone defect area could promote bone tissue regeneration using a rat model of a jawbone defect in periapical periodontitis. Histologically, the new periodontal tissue in the bone defect area was thicker, and the number of blood vessels was higher by local injection of HUC-MSCs-EVs, and fewer inflammatory cells and osteoclasts were formed compared to bone meal filling. In vitro, HUC-MSCs-EVs can be internalized by rat bone marrow mesenchymal stem cells (BMSCs), enhancing the ability for proliferation and migration of BMSCs. Additionally, 20 μg/mL HUC-MSCs-EVs can facilitate the expression of osteogenic genes and proteins including runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), and osteopontin (OPN). In summary, in vivo and in vitro experiments showed that HUC-MSCs-EVs can promote bone regeneration in periapical periodontitis, and the effect of tissue regeneration is better than that of traditional bone meal treatment. Therefore, local injection of HUC-MSCs-EVs may be an effective method to promote jawbone regeneration in periapical periodontitis.

Cathepsin C in health and disease: from structural insights to therapeutic prospects

Cathepsin C (CTSC) is a lysosomal cysteine protease constitutively expressed at high levels in the lung, kidney, liver, and spleen. It plays a key role in the activation of serine proteases in cytotoxic T cells, natural killer cells (granzymes A and B), mast cells (chymase and tryptase) and neutrophils (cathepsin G, neutrophil elastase, proteinase 3) underscoring its pivotal significance in immune and inflammatory defenses. Here, we comprehensively review the structural attributes, synthesis, and function of CTSC, with a focus on its variants implicated in the etiopathology of several syndromes associated with neutrophil serine proteases, including Papillon-Lefevre syndrome (PLS), Haim-Munk Syndrome (HMS), and aggressive periodontitis (AP). These syndromes are characterized by palmoplantar hyperkeratosis, and early-onset periodontitis (severe gum disease) resulting in premature tooth loss. Due to the critical role played by CTSC in these and several other conditions it is being explored as a potential therapeutic target for autoimmune and inflammatory disorders. The review also discusses in depth the gene variants of CTSC, and in particular their postulated association with chronic obstructive pulmonary disease (COPD), COVID-19, various cancers, anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, sudden cardiac death (SCD), atherosclerotic vascular disease, and neuroinflammatory disease. Finally, the therapeutic potential of CTSC across a range of human diseases is discussed.

Neural epidermal growth factor-like 1 protein (Nell-1) alleviates periodontal tissue destruction in periodontitis by regulating the ratio of M2/M1 macrophage phenotypes

BACKGROUND

Periodontitis is a common oral disease with high prevalence worldwide. Neural epidermal growth factor-like 1 protein (Nell-1) has recently been reported to have anti-inflammation effects and may be a drug candidate for osteoarthritis. However, its immunotherapeutic effects in periodontitis remain unknown. Therefore, this study aimed to investigate the effects of Nell-1 on periodontitis in terms of macrophage polarization and analyze its possible underlying mechanism.

METHODS

A rat ligation-induced experimental periodontitis model was established and locally injected with Nell-1 (n = 6/group). Periodontal tissue destruction and macrophage polarization in vivo were analyzed using micro-CT, histology analysis, and western blot. Enzyme-linked immunosorbent assay was used to evaluate serum inflammatory cytokines. Then, the RAW 264.7 macrophage cells were treated with lipopolysaccharide (LPS), Nell-1, and the c-Jun N-terminal kinases (JNK) inhibitor (SP600125). RT-PCR, western blot, and flow cytometry were performed to further analyze the effect of Nell-1 on macrophage polarization and the underlying mechanism in vitro.

RESULTS

Local treatment with Nell-1 significantly alleviated the destruction of alveolar bone and fibers in periodontitis, and upregulated the ratio of M2/M1 macrophages in periodontal tissues (P < 0.05). In vitro, Nell-1 at the concentrations of 200 and 500 ng/mL could significantly inhibit the expression of M1-related inflammatory factors in LPS-stimulated macrophages, and increase the expression of M2-related markers, regulating the macrophage phenotype switch into M2 (P < 0.05). The mRNA of JNK and relative protein level of phospho-JNK/JNK were also upregulated by Nell-1 (P < 0.05). Additionally, the JNK inhibitor (SP600125) could reverse the effect of Nell-1 on macrophage polarization (P < 0.05).

CONCLUSIONS

Nell-1 could modulate the ratio of M2/M1 macrophages possibly through the JNK/MAPK signaling pathway, subsequently attenuating the inflammation and destruction of periodontal tissues caused by periodontitis.

The comprehensive evaluation of oral and fecal microbiota in patients with acromegaly

PURPOSE

The alteration of the microbiota in the mouth and gut could potentially play a role in the pathogenesis of various diseases, and conversely, these diseases may have an influence on the composition of the gut microbiota. Acromegaly disease can potentially affect physiological processes in the mouth and gut. The present study was designed to investigate the relationship between acromegaly and the oral and gut microbiota, as data on this topic are scarce.

METHODS

This was a multicenter, cross-sectional study. Our study included individuals diagnosed with acromegaly (who were treated and followed up, and also as an another group of patients with newly diagnosed acromegaly) and healthy participants. All three groups were assessed and compared based on age, sex, serum IGF-1, body mass index BMI as well as their stool and oral microbiota We collected demographic information from the patients, collected fecal and oral samples, performed DNA isolation followed by 16 S rRNA sequencing, and then performed bioinformatic analysis. We also analyzed the oral and fecal samples with respect to medical and surgical treatment and disease control status, specific treatments received for acromegaly, presence of comorbidities, hypopituitarism status, presence of intestinal polyps.

RESULTS

One hundred and three patients with acromegaly, 15 newly diagnosed patients with acromegaly without comorbidities and 34 healthy controls were included in the study. The Firmicutes/Bacteroidetes ratio was significantly lower in patients with acromegaly who received treatment (medical and/or surgical) than in healthy controls. In addition, a significant difference was found in the fecal and oral microbiota of patients with acromegaly with disease control compared to healthy controls. Furthermore, a significant difference was found in the fecal and oral microbiota of patients with acromegaly without disease control. Nevertheless, it was not possible to establish a clear relationship between disease control status, the presence of intestinal polyps, the presence of type 2 diabetes and the composition of the oral and gut microbiota in acromegalic patients who had received different forms of treatment.

CONCLUSION

Patients with acromegaly show distinct gut microbiota profiles, and it is evident that factors beyond the GH/IGF-1 axis play a role in shaping the gut microbiota of individuals with acromegaly.

Hyaluronic Acid in Bone Regeneration: Systematic Review and Meta-Analysis

AIM

The aim of this systematic review and meta-analysis was to assess possible histomorphometric differences in new bone formation and in remaining graft particles when hyaluronic acid (HA) was added and mixed with graft materials in bone regeneration.

MATERIALS AND METHODS

This review was registered at the International Prospective Register of Systematic Reviews (PROSPERO) of the National Institute of Health Research (registration number CRD42024530030). Electronic research was performed, and involved studies published up to 29 February 2024 using a specific word combination. The primary outcome was to assess possible histomorphometric differences in new bone formation and in remaining graft particles when HA was added and mixed with graft materials in bone regeneration. The search resulted in 138 potential studies. Meta-analyses were performed using the fixed and random effects model to identify significant changes in new bone formation and in the remaining graft particles.

RESULTS

After screening procedures, only three randomized controlled trials fulfilled the inclusion criteria and were selected for qualitative and quantitative analysis. The effect size of HA in the new bone formation was not statistically significant at 95% CI (Z = 1.734, p-value = 0.083, 95 % CI -,399; 6516). The effect size of HA in the remaining graft particles was not statistically significant at 95% CI (Z = -1.042, p-value = 0.297, CI -,835; 255).

CONCLUSIONS

Within the limitations of the present systematic review and meta-analysis, the addition of HA to bone graft did not result in significant changes in bone regeneration procedures in terms of new bone formation and residues, even if the included studies showed encouraging and promising results.

Evaluation of oral health services and challenges faced by oral health practitioners working in Nyarugenge, Rwanda

OBJECTIVE

Oral healthcare professionals encounter considerable challenges while providing services to curb the oral disease burden. The aim of this study was to explore the challenges faced by oral health practitioners providing oral health services in Nyarugenge, Rwanda and to appraise the availability and adequacy of oral hygiene equipment, instruments, and materials.

METHODS

This was a cross-sectional concurrent mixed methods study. The quantitative and qualitative parts were independent during data collection and analyses and merged during the interpretation phase. All seven public health facilities and 14 dental professionals working in Nyarugenge were included in the study. Data were collected using an audit checklist and an in-depth interview guide. Descriptive statistics were used to analyze the quantitative data. The interviews were analyzed using thematic content analysis.

RESULTS

Most of the dental health professionals were dental therapists (n = 11), women (n = 9), aged 31-40 years (n = 7), and with 11-20 years' experience as oral health practitioners (n = 6). There were five health centers and two hospitals that were audited for equipment, instruments, and materials. The audit of the facilities revealed that most facilities have dental equipment and instruments, but none have adequate preventive dental instruments and materials. Four broad themes emerged from the interviews with the oral health practitioners, namely human resources, supply chain management, patients' oral health awareness and service rendering, and strategic management and administration. The most significant challenges oral health practitioners faced included high dental practitioner/patient ratios, lack of adequate and appropriate equipment and materials, patients' lack of oral health awareness, and a lack of administrative support.

CONCLUSIONS

Well-established community preventive interventions, such as a mobile oral health App, could reduce the patient/provider ratio by increasing population awareness of oral health and encouraging healthy behaviours. The management of the health facilities should address the human resource challenges and equipment supply chain issues.

Bacteroides fragilis in saliva: investigating links with ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is a long-term bowel inflammation of unknown cause. Recent research points to gut microbiota, especially Enterotoxigenic Bacteroides fragilis (ETBF), in UC's development. This study examined the presence of Bacteroides fragilis (B. fragilis) and ETBF in the saliva of UC patients and Healthy Controls (HCs) in Iran.

METHODS

A total of 40 UC patients and 40 healthy controls were included in the study. Saliva samples were collected and analyzed for the presence of B. fragilis and ETBF using real-time polymerase chain reaction (PCR).

RESULTS

B. fragilis was more prevalent in HCs (70%) than UC patients (67.5%), but not significantly (p = 0.809). ETBF was significantly more prevalent in UC patients (50%) than HCs (10%) (p < 0.0001). The mean count of B. fragilis was higher in UC patients, but not significantly (p = 0.47). However, the mean count of ETBF was significantly higher in UC patients (p = 0.000089). In terms of gender, the number of B. fragilis in women was not significant (p = 0.16), but the number of ETBF was significantly higher in women with UC (p = 0.000458). For men, no significant differences were observed.

CONCLUSIONS

The present study suggest a higher prevalence of B. fragilis observed in UC patients compared to HCs. Further research is needed to confirm these findings and explore potential mechanisms underlying this association.

Anterior Hyperfunction Syndrome: Literature Review and Conceptual Model

Combined Kelly syndrome, also known as anterior hyperfunction syndrome, is a complex pathological condition of the stomatognathic system, originally established by five characteristics but primarily triggered by edentulism, specifically, the absence of the upper and posterior mandibular teeth. This condition is characterized by a series of clinical features, such as bone loss, tuberosity growth, enamel wear, periodontal damage, muscle fatigue, pain, and temporomandibular joint issues. However, these features are not unique and rather reflect an oral hyperfunction state. There is a lack of consensus on the best way to assess and diagnose this condition, which is proposed to be understood as an "oral hyperfunction state" rather than a syndrome. This study aims to conduct a literature review to analyze the available information on anterior hyperfunction syndrome in dentistry, with the goal of proposing a conceptual model of the etiological risk factors that contribute to early diagnosis and the prevention of complications. This approach has important clinical implications, as it would allow for the early identification and management of risk factors, thus improving the quality of life of patients and preventing malpractice that could compromise their oral health.

Risk Indicators of Peri-Implant Diseases in Public and Private Clinics: A Multicenter Study

Methods

Patients examined during postloading maintenance visits were included in this study. The presence of peri-implant mucositis, peri-implantitis and several patient- and implant-related independent variables was recorded. Statistical analysis was performed using the logistic regression analysis. The odds ratios (OR) of the potential association between each variable and the occurrence of peri-implant diseases were evaluated.

Results

Among the 114 participants with 403 implants, peri-implantitis was found in at least one implant of nine individuals (7.89%), and a total of 13 implants were affected by peri-implantitis (3.22%). The univariate regression analysis revealed a statistically significant association between arch (OR = 4.81; 95% CI = 1.27-31.36) and soft tissue thickness (OR = 4.07; 95% CI = 1.33-13.73) with the occurrence of peri-implantitis. The multivariate analysis confirmed the significant impact of soft tissue thickness (OR = 3.60; 95% CI = 1.16-12.24).

Conclusion

The occurrence of peri-implant diseases can be influenced by various factors. However, in order to accurately identify risk indicators, it is necessary to conduct long-term prospective studies.

VMT/ACP/Dextran composite nanosheets against dental caries through promoting mineralization of dentin tubules, pH buffering, and antibacterial

Dental caries is a worldwide public healthcare concern, and is closely related to the acidic environment that caused by bacterial decomposition of food. In this study, a two-step ion exchange liquid-phase stripping method was applied to strip out vermiculite (VMT) nanosheets, then amorphous calcium phosphate (ACP) and dextran were inserted between the VMT nanosheets interlayer to obtain a composite two-dimension nanosheets (VMT/ACP/Dextran). VMT/ACP/Dextran composite nanosheets exhibited excellent biocompatibility and could provide exogenous Ca2+and PO43- from ACP, provide SiO44-, Mg2+, Fe2+ and obtain buffering pH and antibacterial properties from VMT, as well as improve suspension stability and targeting Streptococcus mutans through glucan. The in vitro study showed that the composite materials could promote the mineralization and sealing of dentin tubules by releasing active ions, buffer pH 4.5 (a value close to the pH in the dental plaque environment) to pH 6.6-7.1 (values close to the pH in human saliva) through ion exchange, and exert antibacterial effects by targeting Streptococcus mutans and exerting oxidase like and peroxidase like activities to produce reactive oxygen species (ROS). The in vivo animal study showed that daily cleaning teeth using VMT/ACP/Dextran composite nanosheets could effectively reduce the incidence rate and severity of dental caries in rats. Taking together, the developed VMT/ACP/Dextran composite nanosheets, which integrated the excellent properties of VMT, ACP and dextran, can effectively prevent dental caries through a combination of factors such as buffering acids, antibacterial properties, and promoting calcification, and may be used as an active ingredient for daily oral hygiene or filling materials to prevent and treat dental caries.

Effect of different anticoagulants and antiplatelets on intraoral bleeding time during professional oral hygiene session

OBJECTIVE

Patients with thromboembolic problems, prosthetic valves, or coagulation issues are commonly prescribed anticoagulants and antiplatelets. Anticoagulant and antiplatelet medication might constitute a challenge for dentists and dental hygienists since possible prolonged bleeding might interfere with dental procedures. The aim of the present study was to examine the bleeding durations associated with various anticoagulants and antiplatelets during professional dental hygiene sessions, utilizing a modified Ivy test adapted for the oral context.

MATERIALS AND METHODS

Ninety-three consecutive patients undergoing professional oral hygiene were recruited. Debridement during oral hygiene was performed using ultrasonic mechanical instrumentation, and bleeding sites were assessed and treated with gentle pressure using sterile gauzes. The time for bleeding cessation was recorded. Patients were categorized into six groups based on their drug intake, Control: no anticoagulants or antiplatelets DTI: direct thrombin inhibitors (dabigatran) AntiXa: directa factor Xa inhibitors (endoxaban, apixaban, rivaroxaban) VKA: vitamin K antagonists (warfarin, acenocoumarol) SAPT: single anti-platelet therapy (acetylsalicylic acid or clopidogrel) DAPT: dual anti-platelet therapy (acetylsalicylic acid and clopidogrel). Bleeding time was measured in seconds and mean values were assessed among the different groups. Differences between groups were investigated with Kruskal-Wallis test followed by Dunn's post-hoc correction for multiple comparisons or two-way ANOVA followed by Dunnett post-hoc; RESULTS: Control patients presented the lowest bleeding time 50 s, followed by AntiXa (98), SAPT (105), DTI (120), DAPT (190) and VKA (203). A statistically significant difference was present among control and DTI (p = 0.004), VKA (p < 0.001), DAPT (p < 0.001).

CONCLUSIONS

Based on the present outcomes, an increased risk of prolonged bleeding emerged in patients taking VKA and DAPT.

CLINICAL SIGNIFICANCE

bleeding did not interfere with the oral hygiene session The optimal period for dental treatment of these patients should be 2-3 h before the next dose, without the need to temporarily suspend the medication.

The association between preterm birth and the supplementation with vitamin D and calcium during pregnancy

BACKGROUND AND AIM

Although vitamin D (VD) supplementation or calcium supplementation during pregnancy has become publicly accepted and part of health care behavior, the effect of co-supplementation on preterm birth remains unclear.

OBJECTIVE

To explore whether the supplementation with vitamin D and calcium during pregnancy is associated with preterm birth.

METHODS

The study was the baseline survey from the birth cohort in Jinan, which was built at one month after the baby birth. Preterm birth and monthly VD and calcium supplementation during pregnancy were obtained by the questionnaire. The logistic model was conducted to exam the association. The distributed lag nonlinear model was applied to explore the critical window for the supplements.

RESULTS

Preterm birth occurred in 4.4 % (285/6501) of the study subjects with single live births and the rates were 39.7% and 82.6% for single VD supplementation or calcium supplementation in pregnancy. The adjusted OR (95% CI) for preterm birth was 1.428 (1.115-1.829) related to VD and 0.883 (0.652-1.216) related to calcium. It is interesting to note that the increased risk of preterm birth with VD supplementation during pregnancy was only seen in pregnant women who supplemented with calcium (OR was 1.600) and had a significant increase in preterm birth weight (P = 0.040). Besides, supplementation VD with calcium during pregnancy from the 3rd to 6th month during pregnancy was associated with preterm birth (OR3rd = 1.216, 95% CI: 1.119-1.320; OR4th = 1.275, 95% CI: 1.152-1.411; OR5th = 1.279, 95% CI: 1.130-1.446; OR6th = 1.208, 95% CI: 1.076-1.356). Moreover, birth weight mediated 10.8% of the total effect of supplementation on preterm birth.

CONCLUSION

Women who supplemented with VD among taking calcium during pregnancy were more likely to experience preterm birth, and birth weight partly mediates the effect. The critical window for association between supplements and preterm birth may be from the 3rd to 6th weeks of pregnancy.

Dental Pathophysiology of Odontogenic Sinusitis: Oral Surgical Complications

The article explores the understudied pathophysiology of odontogenic sinusitis (ODS) development as a result of oral surgical complications such as oroantral communication (OAC) or fistula (OAF), maxillary sinus bone grafting, and dental implantation. A temporary OAC presents most often after dental extraction, especially with posterior maxillary teeth, though can happen with any oral surgical intervention. Maxillary sinus augmentation can also cause ODS, and while the pathophysiology is incompletely understood, it may be related to OAC/OAF formation or bone graft infection. Dental implants may also lead to ODS either via displacement into the sinus, partial protrusion into the sinus, or peri-implantitis.

Associations of tooth loss with risk of all-cause and cause-specific mortality among US adults with diabetes mellitus

OBJECTIVES

To determine whether tooth loss affects all-cause and cause-specific mortality in a nationally representative sample of adults with diabetes mellitus (DM) in the United States.

METHODS

This prospective cohort study involved 8207 participants aged 30 years or older at baseline, all diagnosed with diabetes mellitus and enrolled in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018. Tooth loss was stratified into 28 teeth (complete), 20-27 teeth (tooth loss), 9-19 teeth (lacking functional), 1-8 teeth (severe tooth loss) and edentulism. To estimate hazard ratios (HRs) and 95 % confidence intervals (CIs) for all-cause and specific-cause mortality in diabetes mellitus participants according to tooth loss, multivariate cox proportional hazards regression models were used. Relationships between mortality and quartiles of mean tooth loss levels were analyzed, with the lowest quartile as the baseline for comparisons.

RESULTS

During a median of 6.92 years of follow-up, 2317 deaths were documented. After multivariate adjustments, higher tooth loss levels were significantly and non-linearly associated with higher risks of all-cause, CVD-related and DM-related mortality among participants with DM. When compared with the reference group of mean tooth loss levels, the highest quartile showed significantly increased risks: all-cause mortality (HR, 2.11; 95 % CI, 1.53-2.91, P-trend < 0.001), CVD-related mortality (HR, 3.24, 95 % CI, 1.54-6.85, P-trend < 0.001) and DM-related mortality (HR, 2.78, 95 % CI, 1.15-6.68, P-trend < 0.001).

CONCLUSIONS

Tooth loss is associated with an increased risk of all-cause, CVD-related and diabetes mellitus mortality among adults with diabetes mellitus in the US.

CLINICAL SIGNIFICANCE

This study presents evidence for physicians and dentists that higher tooth loss was significantly associated with increased risk of all-cause, CVD-related and diabetes mellitus mortality in a dose-response manner among adults with diabetes mellitus. Therefore, assessment of survival in individuals with diabetes mellitus could pay attention to the tooth loss.

Collagen patches releasing phosphatidylserine liposomes guide M1-to-M2 macrophage polarization and accelerate simultaneous bone and muscle healing

Bilateral communication between bones and muscles is essential for healing composite bone-muscle injuries from orthopedic surgeries and trauma. However, these injuries are often characterized by exaggerated inflammation, which can disrupt bone-muscle crosstalk, thereby seriously delaying the healing of either tissue. Existing approaches are largely effective at healing single tissues. However, simultaneous healing of multiple tissues remains challenging, with little research conducted to date. Here we introduce collagen patches that overcome this overlooked issue by harnessing the plasticity of macrophage phenotypes. Phosphatidylserine liposomes (PSLs) capable of shifting the macrophage phenotype from inflammatory M1 into anti-inflammatory/prohealing M2 were coated on collagen patches via a layer-by-layer method. Original collagen patches failed to improve tissue healing under inflammatory conditions coordinated by M1 macrophages. In contrast, PSL-coated collagen patches succeeded in accelerating bone and muscle healing by inducing a microenvironment dominated by M2 macrophages. In cell experiments, differentiation of preosteoblasts and myoblasts was completely inhibited by secretions of M1 macrophages but unaffected by those of M2 macrophages. RNA-seq analysis revealed that type I interferon and interleukin-6 signaling pathways were commonly upregulated in preosteoblasts and myoblasts upon stimulation with M1 macrophage secretions, thereby compromising their differentiation. This study demonstrates the benefit of PSL-mediated M1-to-M2 macrophage polarization for simultaneous bone and muscle healing, offering a potential strategy toward simultaneous regeneration of multiple tissues. STATEMENT OF SIGNIFICANCE: Existing approaches for tissue regeneration, which primarily utilize growth factors, have been largely effective at healing single tissues. However, simultaneous healing of multiple tissues remains challenging and has been little studied. Here we demonstrate that collagen patches releasing phosphatidylserine liposomes (PSLs) promote M1-to-M2 macrophage polarization and are effective for simultaneous healing of bone and muscle. Transcriptome analysis using next-generation sequencing reveals that differentiation of preosteoblasts and myoblasts is inhibited by the secretions of M1 macrophages but promoted by those of M2 macrophages, highlighting the importance of timely regulation of M1-to-M2 polarization in tissue regeneration. These findings provide new insight to tissue healing of multiple tissues.

Prevalence of rapid calculus formers and its associated factors amongst patients visiting a dental hospital: a preliminary investigation

BACKGROUND

This study focuses on the determination and classification of patients as rapid or slowcalculusformersbasedontherateofcalculusformationafteroralprophylaxis. It also aims to determine the factors that positively impact the formation and deposition of calculus in patients and identify the factors that accelerate or decelerate the deposition of calculus.

METHODS

The study was conducted in the Department of Periodontology, Dr Harvansh Singh Judge Institute of Dental Sciences and Hospital, Panjab University Chandigarh, India. We examined 51 patients after a month of the oral prophylaxis, recorded the amount of calculus present in the oral cavity, and then recorded a detailed history which was briefly divided into Age, Sex, Residence, Oral habits, and maintenance of oral hygiene.

RESULTS

An evident and meaningful link was found between age and the rate at which dental calculus forms. The average age of individuals differed significantly between the rapid and slow calculus formers, which could be ascribed to the decline in manual dexterity as age increases, resulting in less effective oral hygiene habits, including toothbrushing. None of the other factors dietary and oral hygiene related could be identified distinctly, probably owing to the small sample of the study. The oral health status exhibited a significant difference between slow and rapid calculus formers.

CONCLUSIONS

Within the limitations of the study, the data analyzed, identified age as a significant determinant that impact the rate of formation of calculus in patients and reported a significant difference in the oral health status of rapid and slow calculus formers.

Evolution, development, and regeneration of tooth-like epithelial appendages in sharks

Sharks and their relatives are typically covered in highly specialized epithelial appendages embedded in the skin called dermal denticles; ancient tooth-like units (odontodes) composed of dentine and enamel-like tissues. These 'skin teeth' are remarkably similar to oral teeth of vertebrates and share comparable morphological and genetic signatures. Here we review the histological and morphological data from embryonic sharks to uncover characters that unite all tooth-like elements (odontodes), including teeth and skin denticles in sharks. In addition, we review the differences between the skin and oral odontodes that reflect their varied capacity for renewal. Our observations have begun to decipher the developmental and genetic shifts that separate these seemingly similar dental units, including elements of the regenerative nature in both oral teeth and the emerging skin denticles from the small-spotted catshark (Scyliorhinus canicula) and other chondrichthyan models. Ultimately, we ask what defines a tooth at both the molecular and morphological level. These insights aim to help us understand how nature makes, replaces and evolves a vast array of odontodes.

Oral microbiota and gastric cancer: recent highlights and knowledge gaps

Gastric cancer is one of the most common malignant tumors worldwide and has a high mortality rate. However, tests for the early screening and diagnosis of gastric cancer are limited and invasive. Certain oral microorganisms are over-expressed in gastric cancer, but there is heterogeneity among different studies. Notably, each oral ecological niche harbors specific microorganisms. Among them, tongue coating, saliva, and dental plaque are important and unique ecological niches in the oral cavity. The colonization environment in different oral niches may be a source of heterogeneity. In this paper, we systematically discuss the latest developments in the field of the oral microbiota and gastric cancer and elucidate the enrichment of microorganisms in the oral ecological niches of the tongue coatings, saliva, and dental plaque in gastric cancer patients. The various potential mechanisms by which the oral microbiota induces gastric cancer (activation of an excessive inflammatory response; promotion of proliferation, migration, invasion, and metastasis; and secretion of carcinogens, leading to imbalance in gastric microbial communities) are explored. In this paper, we also highlight the applications of the rapeutics targeting the oral microbiota in gastric cancer and suggests future research directions related to the relationship between the oral microbiota and gastric cancer.

Examination of Various Abutment Designs Behavior Depending on Load Using Finite Element Analysis

Studies on dental implant abutments' geometric design and material selection offer significant innovations and results. These studies aim to improve the abutments' functionality and aesthetic performance, minimize microcavities' formation, and ensure implant-supported prostheses' longevity. For example, CAD-CAM fabricated custom abutments have been found to produce a better marginal fit and fewer microgaps than standard abutments. In an in vitro study, transepithelial abutments offered lower microgap values than titanium-based abutments and provided a better fit at the implant-abutment interface. It is known that studies to improve mechanical and biological performance with Polyether Ether Ketone (PEEK) material have been addressed. New materials such as PEEK and zirconia have offered significant advantages in biocompatibility and aesthetics. Along with those studies, different abutment designs are also important. Abutment geometry is optimized to improve stress distribution and minimize peri-implant bone loss. In implant and abutment connections with different angles, mechanical life performances may vary depending on static and dynamic load. These studies emphasize the importance of material research on different types of connections to improve dental implants' durability, homogeneous load distribution, and reliability. The abutment parts used in implant treatment are insufficient to distribute the load homogeneously against chewing pressure due to their materials and geometry. Non-uniform load distribution damages the abutment and the prosthetic crown, accelerating the wear process. This study aimed to create different abutment designs to improve dental implants' biomechanical performance and longevity. This study aimed to increase the mechanical durability of the implant-abutment connection by reducing stress concentrations in response to masticatory compression on the abutment in different directions and forces and to guarantee the long-term success of the implant system by providing a more homogeneous stress distribution. It aimed to apply different forces in the axial direction to these models in a simulation environment and to calculate and compare the deformation and stress load distribution. As a method, three-dimensional models of the parts used in implant treatments and forming the implant system were designed. Different abutment designs were created with these models. Taking the current material values used in implant treatments as a reference, finite element analysis (FEA) was performed by applying different axial loads to each implant system model in the ANSYS software (version 24.1). Comparative analysis graphs were prepared and interpreted for the stress values obtained after the applied load. This study evaluated the mechanical performance of different abutment models (A, B, C, D, and E) under a 100 N load using the Kruskal-Wallis test. The Kruskal-Wallis test showed significant differences between the groups (p < 0.001). The greatest difference was observed between models E and A (q' = 6.215), with a significant difference also found between models C and A (q' = 3.219, p < 0.005). Regarding stress values, the highest stress on the abutment was observed in Model B (97.4 MPa), while the lowest stress was observed in Model E (9.6 MPa). The crown exhibited the highest stress in Model B (22.7 MPa) and the lowest in Model E (17.3 MPa). The implant stress was highest in Model C (14.8 MPa) and lowest in Model B (11.3 MPa). The stress values for the cortical bone and cancellous bone were quite similar across the models, showing no significant differences. These findings indicate that the abutment design and material selection significantly impact mechanical performance. Among the implant systems created with five different abutment models, in which the existing abutment geometry was also compared, homogeneous and axial distribution of the load on the abutment was achieved, especially with viscoelastic and surface area increased abutment designs. Clinically, the inadequacy and limited mounting surface or geometry of the abutments used in today's implant treatment applications have led to different design searches. It was concluded that the designs in this study, which are considered alternatives to existing abutment models, contribute positively to the mechanical life of the abutment material, considering the von Mises stresses and directions. This study brings a new perspective to today's practices and offers an alternative to treatment practices.

The Current Molecular and Cellular Landscape of Chronic Obstructive Pulmonary Disease (COPD): A Review of Therapies and Efforts towards Personalized Treatment

Chronic obstructive pulmonary disease (COPD) ranks as the third leading cause of global illness and mortality. It is commonly triggered by exposure to respiratory irritants like cigarette smoke or biofuel pollutants. This multifaceted condition manifests through an array of symptoms and lung irregularities, characterized by chronic inflammation and reduced lung function. Present therapies primarily rely on maintenance medications to alleviate symptoms, but fall short in impeding disease advancement. COPD's diverse nature, influenced by various phenotypes, complicates diagnosis, necessitating precise molecular characterization. Omics-driven methodologies, including biomarker identification and therapeutic target exploration, offer a promising avenue for addressing COPD's complexity. This analysis underscores the critical necessity of improving molecular profiling to deepen our comprehension of COPD and identify potential therapeutic targets. Moreover, it advocates for tailoring treatment strategies to individual phenotypes. Through comprehensive exploration-based molecular characterization and the adoption of personalized methodologies, innovative treatments may emerge that are capable of altering the trajectory of COPD, instilling optimism for efficacious disease-modifying interventions.

Association of periodontitis with cardiovascular and all-cause mortality in hypertensive individuals: insights from a NHANES cohort study

BACKGROUND

The objective of this research is to clarify the impact of periodontitis on overall and cardiovascular-related death rates among hypertensive individuals.

METHOD

A total of 5665 individuals with hypertension were included from the National Health and Nutrition Examination Survey (NHANES) data spanning 2001-2004 and 2009-2014. These individuals were divided into two groups based on the presence or absence of periodontitis and further stratified by the severity of periodontitis. We employed weighted multivariate Cox proportional hazards regression and Kaplan-Meier curves (log-rank test) to evaluate the impact of periodontitis on all-cause and cardiovascular mortality. Additional analyses, including adjustments for various covariates, subgroups, and sensitivity analyses, were conducted to ensure the robustness and reliability of our results.

RESULT

Over an average follow-up duration of 10.22 years, there were 1,122 all-cause and 297 cardiovascular deaths. Individuals with periodontitis exhibited an elevated risk of all-cause mortality (HR = 1.33, 95% CI 1.18-1.51; p < 0.0001) and cardiovascular mortality (HR = 1.48, 95% CI 1.15-1.89; p = 0.002). Moreover, we observed a progressive increase in both all-cause mortality and cardiovascular mortality (p for trend are both lower than 0.001) and correlating with the severity of periodontitis. These associations remained consistent across various subgroup and sensitivity analyses.

CONCLUSION

Our findings suggest a significant association between periodontitis and increased risks of all-cause and cardiovascular mortality among hypertensive individuals. Notably, the severity of periodontitis appears to be a critical factor, with moderate to severe cases exerting a more pronounced impact on all-cause mortality. Additionally, cardiovascular disease mortality significantlly increases in individuals with varying degrees of periodontitis.

Efficiency of periodontal treatment to improve type 2 diabetes mellitus outcomes: A systematic review and meta-analysis of economic evaluations

BACKGROUND

To assess the efficiency of periodontal treatment (PT) in improving diabetes-related outcomes in adults with type 2 diabetes mellitus (T2DM) and periodontitis, providing an updated and comprehensive synthesis from economic evaluations (EE).

METHODS

Seven databases and one register were independently searched by two reviewers for articles published up to 8 May 2024. Studies that assessed the efficiency of PT versus no treatment or other dental treatments were included. Risk of bias was assessed using the Cochrane RoB 2, ROBINS-I and ECOBIAS tools for the first stage of EE and the CHEERS checklist and NICE quality appraisal tool for overall EE. Qualitative and quantitative syntheses of the articles were conducted and assessed using the GRADE approach.

RESULTS

Eleven studies were included. PT reduces total healthcare costs, including inpatient and outpatient, diabetes-related costs and other drug costs (low to moderate certainty). A total incremental net benefit of USD 12 348 (2022 currency, 95% CI 12 195-12 500) was estimated from three high-quality model-based cost-utility analyses (high certainty).

DISCUSSION

The inclusion of PT in the comprehensive treatment of patients with T2DM and periodontitis is cost-effective. Future research is required to ensure the transferability of these findings and inform decision makers from different countries.

REGISTRATION

PROSPERO CRD42023443146.

The role of microbiota in nasopharyngeal cancer: Where do we stand?

Nasopharyngeal carcinoma (NPC) is a common head and neck cancer with a poor prognosis. One of the crucial challenges regarding NPC is its pathogenesis. Recent findings highlight the significance of host microbiota in the development of NPC, affected locally by nasopharyngeal microbiota or remotely by oral microbiota. The oral microbiota can migrate to the nasopharyngeal space, thereby impacting the composition of the nasopharyngeal microbiota. Specific bacterial strains have been linked to the development of nasopharyngeal cancer, including Neisseria, Staphylococcus, Leptotrichia, Staphylococcaceae, Granulicatella, Corynebacterium, Fusobacterium, and Prevotella. Several mechanisms have been proposed to elucidate how microbiota dysbiosis contributes to the development of NPC, including triggering tumor-promoting inflammation, reactivating the Epstein-Barr virus (EBV), inducing oxidative stress, weakening the immune system, and worsening tumor hypoxia. In addition, the composition of nasopharyngeal microbiota and the number of tumor-infiltrating microbiota can influence the prognosis and treatment response in patients with NPC. To the best of our knowledge, this is the first review discussing the impacts of the host microbiota on nasopharyngeal cancer pathogenesis, progression, and treatment response.

Association of Oral Microbiome Diversity and All-Cause Mortality in the General US Population and in Individuals With Chronic Diseases: A Prospective Cohort Study

AIM

To investigate whether oral microbiome diversity is associated with all-cause mortality in the general US population and in individuals with chronic diseases.

MATERIALS AND METHODS

We included 8224 individuals with oral microbiome diversity data from the National Health and Nutrition Examination Survey (2009-2012), representing 164,000,205 US adults, using a survey-weighted analysis method. Cox regression analyses were performed to identify the association between oral microbiome diversity and all-cause mortality.

RESULTS

During a survey-weighted mean follow-up period of 8.86 years, 429 all-cause deaths (survey-weighted number: 7,124,920) occurred in 8224 participants. Cox regression analysis revealed that higher oral microbiome diversity was significantly associated with a lower all-cause mortality risk. Significant differences in all-cause mortality risk were observed among the different clusters based on oral microbiome β-diversity (log-rank p < 0.001). Subgroup analyses revealed that the oral microbiome diversity was independently associated with all-cause mortality in individuals with diabetes mellitus and hypertension. A multivariate logistic regression model showed that current smoking and antibiotic use were significantly associated with lower oral microbiome α diversity.

CONCLUSIONS

Higher oral microbiome diversity was significantly associated with a lower all-cause mortality risk in the general US population and in individuals with diabetes mellitus and hypertension.

Association between the number of existing teeth and maintenance dialysis therapy: A cross-sectional study of adult male dentists

Dental caries and periodontal disease are typical oral diseases frequently observed in patients with renal diseases. Tooth loss is an outcome of dental caries and periodontal disease, and the number of existing teeth is an indicator of oral health status. However, the association between the number of existing teeth and end-stage kidney disease (ESKD) has not been investigated in detail. This study aimed to investigate the association between oral health status, expressed by the number of existing teeth, and ESKD. We analyzed data from the second survey of the Longitudinal Evaluation of Multi-phasic, Odontological, and Nutritional Associations in Dentists, a cohort study conducted among members of the Japan Dental Association. From August 2016 to July 2017, self-administered questionnaires were mailed to 16,128 male dentists and 8,722 responded. Among them, 7,479 men with complete data on age, number of existing teeth, and ESKD were included in the analysis. Multivariate logistic regression analysis was conducted, with ESKD as the dependent variable and the number of existing teeth (≥23 teeth and <23 teeth) as the independent variable. Subgroup analysis by age (<65 years and ≥65 years) was also conducted. The <23 teeth group had a significantly higher rate of ESKD than did the ≥23 teeth group. After adjusting for age, body mass index, smoking habits, hypertension, and diabetes mellitus, there was no significant association between having <23 teeth and ESKD in all participants. However, the subgroup analysis revealed a significant association after adjustment for covariates in participants aged <65 years but not in those aged ≥65 years. In conclusion, having <23 teeth was associated with the risk of requiring maintenance dialysis therapy among Japanese men aged <65 years. Therefore, tooth loss may be associated with renal function decline.

Healthy Dietary Pattern Improves Cognitive Function in Elderly Persons With Periodontitis: A Cross-Sectional Study of NHANES

AIM

Cognitive decline is thought to be more prevalent in elderly persons with periodontitis. Greater adherence to Healthy Eating Index (HEI)-2015 has been reported to improve cognitive function in the elderly population. However, whether the benefits of HEI-2015 on cognitive function apply to elderly patients with periodontitis remains unknown.

METHODS

This is a cross-sectional study based on the National Health and Nutrition Examination Survey (NHANES). The data were extracted from database 2011-2014. Cognitive function was measured through the Consortium to Establish a Registry for Alzheimer's Disease battery for immediate recall (CERAD-WL) and delayed recall (CERAD-DR), Animal Fluency Test (AFT), and Digit Symbol Substitution Test (DSST). The data of HEI-2015 were acquired from 24-hour dietary recalls. Weighted linear regression models were performed to investigate the association between HEI-2015 and cognitive function in elderly patients with periodontitis. The associations were further investigated in subgroups of sex, cardiovascular disease status, and depression status.

RESULTS

A total of 1862 participants were included, and 1223 of them had periodontitis. Periodontitis was negatively associated with cognitive function (β = -0.45; 95% confidence interval [CI], -0.87 to -0.03). No statistically significant relationship was observed between HEI-2015 and cognitive function (β = 0.33; 95% CI, -0.02 to 0.69). Low HEI-2015 score was associated with high odds of cognitive decline in patients with periodontitis (β = -0.73; 95% CI, -1.25 to -0.21; P for trend = .01). Higher HEI-2015 was related to the lower incidence of cognitive function decline in patients with periodontitis who were female (β = -0.53; 95% CI, -1.03 to -0.03), had a socioeconomic status from 0 to 3 (β = -0.55; 95% CI, -1.00 to -0.09), did not have cardiovascular disease (β = -0.60; 95% CI, -1.14 to -0.05), and did not have depression (β = -0.57; 95% CI, -1.11 to -0.03).

CONCLUSIONS

Greater HEI-2015 adherence may improve cognitive function amongst elderly patients with periodontitis. Further studies are needed to investigate this putative association in elderly persons with periodontitis.

The Role of Interleukin-8 in the Estimation of Responsiveness to Steps 1 and 2 of Periodontal Therapy

OBJECTIVE

To investigate the association between interleukin-8 (IL-8) levels in gingival crevicular fluid (GCF) and total oral fluid (TOF) and the responsiveness to steps 1 and 2 of periodontal therapy.

MATERIALS AND METHODS

One-hundred and fifty-nine patients affected by periodontitis received steps 1 and 2 of periodontal therapy. At baseline, TOF and GCF samples were collected and analysed for IL-8 (Il-8TOF/IL-8GCF) using flow cytometry. Therapy outcomes were relative proportions of residual periodontal pockets (PPD%), pocket closure (PC) rates and pocket probing depth (PPD) reductions; these were associated with IL-8TOF/IL-8GCF.

RESULTS

High IL-8TOF was significantly associated with higher residual PPD% (p = 0.044) and lower PPD reduction compared to low IL-8TOF (high 0.79 ± 1.20 mm vs. low 1.20 ± 1.20 mm, p < 0.001) in non-smokers, while in smokers high IL-8GCF was related to lower PPD reduction (high 0.62 ± 1.22 mm vs. low 0.84 ± 1.12 mm, p = 0.009). Furthermore, high baseline IL-8TOF was significantly associated with poorer PC rates compared to medium and low concentrations in both non-smokers (high 41% vs. medium 55% vs. low 58%, p < 0.001) and smokers (high 34% vs. medium 44% vs. low 46%, p < 0.001).

CONCLUSION

High IL-8 concentrations at baseline had a significant impact on residual PPD%, PC rates and PPD reduction. The findings suggest that, especially in non-smokers, baseline IL-8 levels collected from the TOF could serve as a component in the estimation of responsiveness to steps 1 and 2 of periodontal therapy.

Metatranscriptomic analysis shows functional alterations in subgingival biofilm in young smokers with periodontitis: a pilot study

OBJECTIVE

This study aimed to assess the influence of smoking on the subgingival metatranscriptomic profile of young patients affected by stage III/IV and generalized periodontal disease.

METHODOLOGY

In total, six young patients, both smokers and non-smokers (n=3/group), who were affected by periodontitis were chosen. The STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines for case-control reporting were followed. Periodontal clinical measurements and subgingival biofilm samples were collected. RNA was extracted from the biofilm and sequenced via Illumina HiSeq. Differential expression analysis used Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and differentially expressed genes were identified using the Sleuth package in R, with a statistical cutoff of ≤0.05.

RESULTS

This study found 3351 KEGGs in the subgingival biofilm of both groups. Smoking habits altered the functional behavior of subgingival biofilm, resulting in 304 differentially expressed KEGGs between groups. Moreover, seven pathways were modulated: glycan degradation, galactose metabolism, glycosaminoglycan degradation, oxidative phosphorylation, peptidoglycan biosynthesis, butanoate metabolism, and glycosphingolipid biosynthesis. Smoking also altered antibiotic resistance gene levels in subgingival biofilm by significantly overexpressing genes related to beta-lactamase, permeability, antibiotic efflux pumps, and antibiotic-resistant synthetases.

CONCLUSION

Due to the limitations of a small sample size, our data suggest that smoking may influence the functional behavior of subgingival biofilm, modifying pathways that negatively impact the behavior of subgingival biofilm, which may lead to a more virulent community.

NLRP3 and AIM2 inflammasomes expression is modified by LPS and titanium ions increasing the release of active IL-1β in alveolar bone-derived MSCs

Periodontitis and peri-implantitis are inflammatory diseases of infectious etiology that lead to the destruction of the supporting tissues located around teeth or implants. Although both pathologies share several characteristics, it is also known that they show important differences which could be due to the release of particles and metal ions from the implant surface. The activation of the inflammasome pathway is one of the main triggers of the inflammatory process. The inflammatory process in patients who suffer periodontitis or peri-implantitis has been mainly studied on cells of the immune system; however, it is also important to consider other cell types with high relevance in the regulation of the inflammatory response. In that context, mesenchymal stromal cells (MSCs) play an essential role in the regulation of inflammation due to their ability to modulate the immune response. This study shows that the induction of NLRP3 and absent in melanoma 2 (AIM2) inflammasome pathways mediated by bacterial components increases the secretion of active IL-1β and the pyroptotic process on human alveolar bone-derived mesenchymal stromal cells (hABSCs). Interestingly, when bacterial components are combined with titanium ions, NLRP3 expression is further increased while AIM2 expression is reduced. Furthermore, decrease of NLRP3 or AIM2 expression in hABSCs partially reverses the negative effect observed on the progression of the inflammatory process as well as on cell survival. In summary, our data suggest that the progression of the inflammatory process in peri-implantitis could be more acute due to the combined action of organic and inorganic components.

Identification of microRNAs expressed in an animal model of periodontal disease and their impact on pathological processes

MicroRNAs represent a class of small RNAs that act to silence genes post-transcriptionally by inhibiting the translation of target messenger RNAs, and this study aimed to understand how miRNAs influence the set-up of periodontal disease. Periodontitis was induced by inserting a ligature into the left first mandibular molar in a rat model, which was kept for the entire 56 days-time of experiment. After 56 days post-periodontitis induction, the histopathological analysis showed an apical extension of the junctional epithelium, with areas of hyperplasia, exocytosis, and a mixed inflammatory infiltrate with a predominance of neutrophils, lymphocytes, and eventual plasma cells in the deeper layers. The cement surface showed areas of irregularity, covered by cementoblasts and irregular surfaces, confirming the set-up of periodontitis. In the sequencing analysis, 26,404 genes were identified, with 132 reaching statistical significance. Among genes with a statistical difference, 18 were found to encode for microRNAs. The identified microRNAs are primarily involved in bone remodeling by acting on fibroblast growth factors, and collagen production. These outcomes demonstrate a signaling role in bone resorption, which is consistent with the histopathological observations that show the installation of inflammation with epithelial migration and the beginning of the repair process, with cementum resorption. The disclosure of how miRNAs may influence the maintaining of periodontal disease will help the development of new dental materials for the prophylaxis and treatment of alveolar bone resorption.

The associations between dietary flavonoids intake and risk of depressive symptom in diabetic patients: Data from NHANES 2007-2008, 2009-2010, and 2017-2018

BACKGROUND

The increasing incidence of depressive symptoms in diabetic patients contributes to the global burden of disease, but few epidemiological studies have evaluated the relationship between dietary flavonoids intake and depressive symptoms in diabetic patients in American adults.

OBJECTIVE

This study intended to evaluate the associations of dietary flavonoids intake and depressive symptoms in diabetic patients in American adults.

METHODS

We conducted a cross-sectional analysis of 1993 adults aged ≥20 years old who participated in the 2007-2008, 2009-2010, and 2017-2018 National Health and Nutrition Examination Surveys (NHANES). Chi-square test and independent-sample t-test were used to compare subjects' characteristics. Logistic regression model was further used to analyze the relationship between dietary flavonoid intake and depressive symptoms in diabetic patients. Restricted cubic spline (RCS) analysis was used to investigate the non-linear relationship between dietary flavonoid intake and the prevalence of depressive symptoms in diabetic patients. The weighted quartile sum (WQS) regression was used to analyze the effect of 29 flavonoids monomers.

RESULTS

The results showed that the total flavonoid intake in the third quartile (OR, 0.635; 95 % CI,0.419-0.962; P, 0.032) was significantly associated with a reduced risk of depressive symptoms in diabetic patients compared with the lowest quartile. And there was a U-shaped association between dietary flavonoid intake and risk of depressive symptoms in diabetic patients. Top contributors of flavonoid monomers were eriodictyol, naringenin, and theaflavin-3'-gallate, accounting for a percentage of 30.83 %, 22.17 %, and 6.92 %, respectively.

CONCLUSION

Moderate (56.07-207.12 mg/day) dietary flavonoid intake was associated with a reduced risk of depressive symptoms in diabetic patients. The important flavonoid monomers were eriodictyol, naringenin, and theaflavin-3'-gallate.

The 50 most cited articles on soft tissue integration of dental implants: A bibliometric analysis

STATEMENT OF PROBLEM

Soft tissue integration helps prevent the bacterial invasion of dental implants, but bibliometric studies on the top 50 most cited articles in the field of soft tissue integration are lacking.

PURPOSE

The purpose of this bibliometric study was to analyze the 50 most cited articles since 1999 to explore global trends and research hotspots.

MATERIAL AND METHODS

A specific search strategy of the Science Citation Index Expanded (Web of Science) was devised, and relevant article-based, journal-based, and author-based parameters were analyzed. Correlation analysis was performed (α=.05).

RESULTS

The number of citations ranged from 71 to 586. Clinical Oral Implants Research was the most cited journal (1722 citations). Berglundh, Tord was the author with the most publications (6 publications) and citations (957 citations). Dental implants and titanium were the keywords with the highest frequency. Switzerland was the country with the highest number of publications (12 publications). Correlation was found between the publication year and average annual citations (P<.001).

CONCLUSIONS

This study determined the scientific progress in soft tissue integration. The surface design of dental implant materials is essential for the soft tissue integration of dental implants. Soft tissue integration has been a focus of interest in the past few years, but many experiments still need to be done to improve soft tissue compatibility with innovative materials.

Applying current European periodontitis clinical practice guidelines is not feasible even for the richest countries in the world

Clinical practice guidelines aim to enhance the quality, equality and consistency of care but often demand more time than is available, rendering adherence impractical and exceeding feasible resources. The 2017 introduction of a new periodontal classification system by the American Academy of Periodontology (AAP) and the European Federation of Periodontology (EFP) sought to refine clinical and epidemiological practices by serving as the basis for clinical practice guidelines and epidemiological investigations around the world. Following this classification, the EFP recommends supportive periodontal care visits every 3-12 months for all periodontitis cases. Given that in Norway, approximately 72% of the adult population are identified as periodontitis cases under the current AAP/EFP case definition, this poses a significant demand on healthcare resources. We calculated that between 60% and 70% of all estimated available working hours available for adult dental care provided by dentists and dental hygienists in Norway in 2017 would be spent on supportive periodontal care visits alone if the recommendations were to be met. This situation calls for a reevaluation of disease definitions and clinical practice guidelines to ensure they are practical, financially feasible and patient-outcome relevant.

Vertical Alveolar Ridge Regeneration by Means of Periosteal Activation-A Proof-of-Principle Study

AIM

To assess the possibility of vertical alveolar ridge augmentation by means of activation of the periosteum.

MATERIALS AND METHODS

Six adult male Beagle dogs were used for the study. All premolars and first molars were extracted, and one vertical saucer-shaped bony defect was created on each side of the mandible. After 3 months of healing, full-thickness muco-periosteal flaps were elevated, and one distraction device was placed on each side of the mandible. The distraction plate was left submerged, and the activation mechanism connected to the distraction rod was exposed intra-orally. The protocol of periosteal activation (PP: periosteal 'pumping') was initiated after a latency of 7 days. The alternation of activation and relaxation at the rate of 0.35 mm/12 h during 5 days was followed by the sole activation of 0.35 mm/12 h for 5 days (PP group). Devices were left inactivated on the contralateral control side of the mandible (C group). All animals were euthanized after 8 weeks of consolidation. Samples were analysed histologically and by means of micro-CT.

RESULTS

New mature lamellar bone was formed over the pristine bone in all groups. More intensive signs of bone modelling and remodelling were observed in the PP group compared to the C group. Mean new bone, bone marrow, connective tissue and total volumetric densities were greater in the PP group (p < 0.001, p = 0.001, p = 0.003 and p < 0.001, respectively). No differences were observed in the relative area parameters. Total tissue volume and bone volume were higher in the PP group (p = 0.031 and p = 0.076, respectively), while the bone mineral densities were higher in the C group (p = 0.041 and p = 0.003, respectively). Trabecular number, trabecular thickness and trabecular separation values were similar between the two groups.

CONCLUSIONS

Regeneration of vertical alveolar bone ridge defects may be enhanced by activation of the periosteum, without the application of bone grafting materials.

Primary stability evaluation of different morse cone implants in low-density artificial bone blocks: A comparison between high-and low-speed drilling

This study aimed to evaluate various biomechanical parameters associated with the primary stability of Maestro and Due Cone implants placed in low-density artificial bones, prepared using high-speed drilling with irrigation and low-speed drilling without irrigation. The insertion torque (IT), removal torque (RT), and implant stability quotient (ISQ) values were recorded for Maestro and Due Cone implants placed in low-density polyurethane blocks (10 and 20 pounds per cubic foot (PCF) with and without a cortical layer) prepared using high-speed and low-speed with or without irrigation using a saline solution, respectively. A three-way ANOVA model and Tukey's post-hoc test were conducted, presenting data as means and standard deviations. P-values equal to or less than 0.05 were considered statistically significant. No statistically significant differences in IT, RT, and ISQ between drilling speeds were observed. However, Maestro implants exhibited lower IT and RT values after high- and low-speed drilling across almost all polyurethane blocks, significantly evident in the 20 PCF density block for IT and in the 20 PCF density block with the cortical layer for the RT with low-speed drilling (IT: 47.33 ± 10.02 Ncm and 16.00 ± 12.49 Ncm for Due Cone and Maestro implants, respectively, with p < 0.01; RT: 44.67 ± 22.81 Ncm and 20.01 ± 4.36 Ncm for Due Cone and Maestro implants, respectively, with p < 0.05) and among the same implant types inserted in different bone densities. Additionally, the study found that for all bone densities and drilling speeds, both implants registered ISQ values exceeding 60, except for the lowest-density polyurethane block. Overall, it can be inferred that low-speed drilling without irrigation achieved biomechanical parameters similar to conventional drilling with both implant types, even with lower IT values in the case of Maestro implants. These findings suggest a promising potential use of low-speed drilling without irrigation in specific clinical scenarios, particularly when focusing on preparation depth or when ensuring proper irrigation is challenging.

Laminin 332 functionalized surface improve implant roughness and oral keratinocyte bioactivity

Objective

The biological seal (BS) at the implant-tissue interface is essential for the success of dental implants (DIs), and the absence of a proper BS can lead to peri-implantitis. The basement membrane (BM) and junctional epithelium are critical for sealing the peri-implant mucosa, and laminin 332 is an important protein in binding the epithelium to the implant surface. The aim of this study was to evaluate the response of oral keratinocytes to titanium dental implant surfaces biofunctionalized with laminin 332.

Design

The dental implant surface was treated with a piranha solution to create hydroxyl (OH) groups, facilitating biofunctionalization with laminin 332. The modified surface underwent scanning electron microscopy, surface roughness evaluation, and chemical composition analysis. Human keratinocytes from the Cal-27 line were then cultured on the modified implants for 24 and 48 h to assess viability, morphology, cytokine secretion, and mRNA expression of tissue repair-associated genes.

Results

The results showed that laminin 332 biofunctionalization of the implant surface resulted in lower values of Ra, Rq and positive surface roughness parameters Rsk, Rku and Rv. The elemental composition showed an increase in nitrogen and carbon content corresponding to protein binding. The biofunctionalized surfaces did not affect cell viability and promoted cytokine secretion (IL-1a and IL-8) and a significant increase (p < 0.05) in MCP-1, EGF, FGF, TGF and VEGF gene expression compared to the control.

Conclusion

In conclusion, laminin 332 coating Ti implants was shown to be effective in promoting keratinocyte adhesion, spreading, and viability. This approach could be an alternative way to improve biocompatibility.