Local wound healing biomarkers for real-time assessment of periodontal regeneration: pilot study

Inflammatory and bone remodelling related biomarkers following periodontal transplantation of the tissue engineered biocomplex

OBJECTIVES

To assess gingival crevicular fluid (GCF) levels of inflammatory and bone remodelling related biomarkers following transplantation of a tissue-engineered biocomplex into intrabony defects at several time-points over 12-months.

MATERIALS AND METHODS

Group-A (n = 9) received the Minimal Access Flap (MAF) surgical technique combined with a biocomplex of autologous clinical-grade alveolar bone-marrow mesenchymal stem cells in collagen scaffolds enriched with an autologous fibrin/platelet lysate (aFPL). Group-B (n = 10) received the MAF surgery, with collagen scaffolds enriched with aFPL and Group-C (n = 8) received the MAF surgery alone. GCF was collected from the osseous defects of subjects via paper strips/30 sec at baseline, 6-weeks, 3-, 6-, 9-, 12-months post-surgery. Levels of inflammatory and bone remodelling-related biomarkers in GCF were determined by ELISA.

RESULTS

Group-A demonstrated significantly higher GCF levels of BMP-7 at 6-9 months than baseline, with gradually decreasing levels of pro-inflammatory and pro-osteoclastogenic markers (TNF-α, RANKL) over the study-period; and an overall decrease in the RANKL/OPG ratio at 9-12 months than baseline (all p < 0.001). In comparison, only modest interim changes were observed in Groups-B and -C.

CONCLUSIONS

At the protein level, the approach of MAF and biocomplex transplantation provided greater tissue regeneration potential as cell-based therapy appeared to modulate inflammation and bone remodelling in residual periodontal defects.

CLINICAL RELEVANCE

Transplantation of a tissue engineered construct into periodontal intrabony defects demonstrated a biochemical pattern for inflammatory control and tissue regeneration over 12-months compared to the control treatments. Understanding the biological healing events of stem cell transplantation may facilitate the design of novel treatment strategies.

CLINICAL DATABASE REGISTRATION

ClinicalTrials.gov ID: NCT02449005.

Biochemical implications of robotic surgery: a new frontier in the operating room

Robotic surgery represents a milestone in surgical procedures, offering advantages such as less invasive methods, elimination of tremors, scaled motion, and 3D visualization. This in-depth analysis explores the complex biochemical effects of robotic methods. The use of pneumoperitoneum and steep Trendelenburg positioning can decrease pulmonary compliance and splanchnic perfusion while increasing hypercarbia. However, robotic surgery reduces surgical stress and inflammation by minimizing tissue trauma. This contributes to faster recovery but may limit immune function. Robotic procedures also limit ischemia-reperfusion injury and oxidative damage compared to open surgery. They also help preserve native antioxidant defenses and coagulation. In a clinical setting, robotic procedures reduce blood loss, pain, complications, and length of stay compared to traditional procedures. However, risks remain, including device failure, the need for conversion to open surgery and increased costs. On the oncology side, there is still debate about margins, recurrence, and long-term survival. The advent of advanced technologies, such as intraoperative biosensors, localized drug delivery systems, and the incorporation of artificial intelligence, may further improve the efficiency of robotic surgery. However, ethical dilemmas regarding patient consent, privacy, access, and regulation of this disruptive innovation need to be addressed. Overall, this review sheds light on the complex biochemical implications of robotic surgery and highlights areas that require additional mechanistic investigation. It presents a comprehensive approach to responsibly maximize the potential of robotic surgery to improve patient outcomes, integrating technical skill with careful consideration of physiological and ethical issues.

Elucidating the molecular healing of intrabony defects following non-surgical periodontal therapy: A pilot study

OBJECTIVE

To elucidate the molecular healing of intrabony defects following non-surgical periodontal therapy (NSPT) using gingival crevicular fluid (GCF).

BACKGROUND DATA

Currently limited information is available regarding the GCF of intrabony defects and the change in biomarker levels in the GCF at early time points following treatment interventions.

METHODS

Twenty-one patients (Periodontitis Stage III or IV) who have received NSPT, contributing one intrabony defect and one healthy site were included in this study. GCF sampling was performed at baseline, 1 day, 5 days and 3 months after NSPT. Multiplex bead immunoassays allowed the profiling of GCF for 27 markers, associated with inflammation and repair/regeneration. A mixed effects model with Bonferroni correction for multiple comparisons was employed to compare the changes in the levels of GCF markers over time.

RESULTS

Following NSPT, changes were observed for several GCF markers, marked by significant increases 1 day post-intervention, before returning to baseline levels by 3 months. Specifically, GCF concentrations of IL-2, IL-4, IL-6, IL-8, MMP-1, MMP-3, TIMP-1 and FGFb significantly increased 1 day after NSPT. Signs of activation of cellular senescence were observed 1 day following treatment of intrabony defects, rapidly regressing by 5 days.

CONCLUSION

Significant molecular changes are observed as early as 1 day following NSPT in intrabony defects, along with activation of cellular senescence.

Molecular profiling of gingival crevicular fluid fails to distinguish between infrabony and suprabony periodontal defects

AIM

To assess the differential molecular profiling of gingival crevicular fluid (GCF) from infrabony and suprabony periodontal defects compared with healthy sites.

MATERIALS AND METHODS

Seventy-five samples from 25 patients with untreated periodontitis stage III-IV were included. Clinical and radiological parameters as well as GCF samples were collected from an infrabony defect, a suprabony defect and a periodontally healthy site per patient. A multiplex bead immunoassay was performed to assess the level of 18 biomarkers associated with inflammation, connective tissue degradation and regeneration/repair.

RESULTS

GCF volume was higher in periodontal sites compared with healthy sites, with no significant difference between infrabony and suprabony defects. Fourteen biomarkers were elevated in infrabony and suprabony sites compared with healthy sites (p < .05). Only interleukin-1α levels were increased in infrabony compared with suprabony sites, whereas there was no difference in probing pocket depth.

CONCLUSIONS

Although the GCF molecular profile clearly differentiates periodontally affected sites from healthy sites, the different architecture between infrabony and suprabony defects is not reflected in GCF biomarker changes.

Matrix Metalloproteinase 9 (MMP-9) and Interleukin-8 (IL-8) in Gingival Crevicular Fluid after Regenerative Therapy in Periodontal Intrabony Defects with and without Systemic Antibiotics-Randomized Clinical Trial

The aim of our study was to assess changes in the levels of IL-8 and MMP-9 in gingival crevicular fluid (GCF) collected from the periodontal pocket before and after regenerative surgery with deproteinized bovine bone mineral (DBBM) and collagen membrane (GTR) either independently (DBBM/GTR) or with the postoperative administration of antibiotic (DBBM/GTR+AB). The study involved 41 patients, each with one intrabony defect. IL-8 and MMP-9 were determined before therapy and after 2 weeks, 4 weeks and 6 months following the surgical procedure by means of dedicated ELISA kits. No statistical differences were observed in the levels of IL-8 and MMP-9 after 2 weeks, 4 weeks and 6 months between the groups. The changes in the level of MMP-9 over time were not statistically significant in any group. The changes in the level of IL-8 were significant for the group given antibiotic but not in the nonantibiotic group in the follow-up period. IL-8 and MMP-9 were found to correlate positively but not after 4 weeks in the test group. Current assessment of IL-8 and MMP-9 obtained from GCF samples provides evidence that collagen matrix turnover occurs actively during the early healing phase in the periodontium after regenerative procedures. We observed positive correlations of MMP-9 and IL-8 throughout the study. However, we failed to reveal any differences regard parameters studied between the two groups.

The Forefront of Dentistry-Promising Tech-Innovations and New Treatments

KNOWLEDGE TRANSFER STATEMENT

This article discusses innovations in technology and treatments that have enormous potential to revolutionize our dental care, including novel concepts in electronic health records, communication between dentists and patients, biologics around diagnosis and treatment, digital dentistry, and, finally, the real-time optimization of information technology. The early implementation and validation of these innovations can drive down their costs and provide better dental and medical services to all members of our society.

Wound fluid sampling methods for proteomic studies: A scoping review

Understanding why some wounds are hard to heal is important for improving care and developing more effective treatments. The method of sample collection used is an integral step in the research process and thus may affect the results obtained. The primary objective of this study was to summarise and map the methods currently used to sample wound fluid for protein profiling and analysis. Eligible studies were those that used a sampling method to collect wound fluid from any human wound for analysis of proteins. A search for eligible studies was performed using MEDLINE, Embase and CINAHL Plus in May 2020. All references were screened for eligibility by one reviewer, followed by discussion and consensus with a second reviewer. Quantitative data were mapped and visualised using appropriate software and summarised via a narrative summary. After screening, 280 studies were included in this review. The most commonly used group of wound fluid collection methods were vacuum, drainage or use of other external devices, with surgical wounds being the most common sample source. Other frequently used collection methods were extraction from absorbent materials, collection beneath an occlusive dressing and direct collection of wound fluid. This scoping review highlights the variety of methods used for wound fluid collection. Many studies had small sample sizes and short sample collection periods; these weaknesses have hampered the discovery and validation of novel biomarkers. Future research should aim to assess the reproducibility and feasibility of sampling and analytical methods for use in larger longitudinal studies.

Biomarkers and Periodontal Regenerative Approaches

The ultimate goal in periodontal therapy is the complete re-establishment of the lost tissues. Dental researchers and clinicians are continuously working to develop current therapeutic techniques and technologies that can regenerate damaged periodontal tissues. Predicting the outcome of the treatment is a challenging endeavor, because a variety of local and systemic variables can affect the success of the applied regenerative therapy. To real-time monitor the biological changes during periodontitis or after periodontal treatment, various biomarkers have been studied in periodontology. This article discusses the available evidence on the use of biomarkers in the detection of periodontal regeneration.

Molecular profiling of intrabony defects' gingival crevicular fluid

AIM

To profile, for the first time, the gingival crevicular fluid (GCF) of intrabony defects against a wide array of inflammatory and regenerative markers.

MATERIALS AND METHODS

Twenty-one patients contributed one intrabony defect and one periodontally healthy site. Clinical and radiographic measures were obtained. GCF samples were analyzed with multiplex bead immunoassays over 27 markers previously identified by our group. Comparisons were performed using Wilcoxon matched-pairs signed-ranks tests, using a Bonferroni corrected α = 0.05/27 = 0.0019.

RESULTS

Intrabony defect sites presented significantly increased GCF volume and disease-associated clinical and radiographic characteristics (p < .05). Intrabony defect sites presented significantly increased IL-1α, IL-1β, IL-6, IFN-γ, and MMP-8 levels compared with periodontally healthy sites (p < .0019). For regeneration markers, significantly higher FGF basic and VEGF levels were observed (p < .0019). Notably, traits of cell senescence were identified for the first time in the GCF.

CONCLUSIONS

The differentiation of intrabony defects from periodontally healthy control sites can be based on clinical and radiographic measures and on a differentiated GCF profile that is site-specific. Alongside catabolic processes, through significant up-regulation of inflammation and connective tissue remodeling, unique molecular characteristics of intrabony defects may render them a microenvironment amenable to regeneration. Traits of the senescence-associated secretory phenotype may suggest the existence of senescent cells during periodontal inflammation in intrabony defects.

Effects of bone morphogenetic proteins on epithelial repair

Epithelial tissue has important functions such as protection, secretion, and sensation. Epithelial damage is involved in various pathological processes. Bone morphogenetic proteins (BMPs) are a class of growth factors with multiple functions. They play important roles in epithelial cells, including in differentiation, proliferation, and migration during the repair of the epithelium. This article reviews the functions and mechanisms of the most profoundly studied BMPs in the process of epithelial damage repair and their clinical significance.

Dynamics of Matrix Metalloproteinase-1 and -8 Secretion in Gingival Crevicular Fluid after Gingival Recession Therapy via MCAT with Either Subepithelial Connective Tissue Graft or Collagen Matrix

OBJECTIVES

The objective of this study was to determine and estimate the changing levels of matrix metalloproteinases 1 and 8 (MMP-1 and MMP-8) in GCF at consecutive stages of healing after root coverage procedure via modified coronally advanced tunnel (MCAT) combined with either sub-epithelial connective tissue graft (SCTG) or collagen matrix (CM) and also to relate those changes to clinical outcomes of both therapeutic approaches.

MATERIALS AND METHODS

The study involved 20 patients with a total of 91 recessions. Those on one side of the mandible received MCAT plus CM while the contralateral ones MCAT plus SCTG. The evaluation of MMP-1 and MMP-8 concentrations in Gingival Crevicular Fluid (GCF) took place at baseline, then at 1, 2, and 4 weeks, and finally at 3 months after surgery. Elisa protocol was applied to determine the levels of MMP-1 and MMP-8 in GCF.

RESULTS

Three-month observation revealed statistically significant changes in MMP-1, MMP-8 and Sulcus Fluid Flow Rate (SFFR) values after implementation of both techniques. A correlation was found between a difference in MMP-1 concentrations and gain in Keratinized Tissue (KT) after SCTG and CM. MMP-8 levels and a Gingival Thickness (GT) gain observed after CM was also correlated.

CONCLUSIONS

A type of augmentative material does appear to determine the dynamics of MMP-1 secretion.

Effects of melatonin in wound healing of dental pulp and periodontium: Evidence from in vitro, in vivo and clinical studies

INTRODUCTION

Database research has revealed that melatonin has beneficial effects in pulpal and periodontal regeneration. Several studies reported protective effects of melatonin against inflammation in several organs including the heart, brain, and teeth. In addition to inflammation reduction, melatonin has been involved in tissue regeneration and wound healing. The aim of this review is to summarize the evidence from in vitro, in vivo and clinical studies on the effects of melatonin in wound healing of dental pulp and periodontium. This review gives a thorough summary of the possible role of melatonin in wound healing of dental pulp and periodontium in connection with anti-inflammatory and antioxidant effects, cell proliferation, and cell differentiation. Any contradictory evidence is also assessed.

METHODS

The PubMed database was searched for all research articles published before April 2020 with the search terms "melatonin" and "dental pulp". Articles with the search terms "melatonin", "periodontal disease" and "bone" published before October 2019 were also included. Non-English articles were excluded.

RESULTS

Melatonin has been shown to reduce inflammation, inhibit cell proliferation and regulate differentiation of pulp cells. Melatonin increased odontoblast activities, resulting in the differentiation in the dental pulp. However, melatonin did not initiate differentiation in undifferentiated pulp cells but seemed to have beneficial effects in periodontitis by promoting periodontium's wound healing.

CONCLUSION

Those findings suggest that melatonin could have beneficial effects on pulpal and periodontal cells under inflammatory conditions. However, discrepancies remain between in vitro and in vivo findings regarding the effect of melatonin on dental pulp and periodontium.

Expression of gingival crevicular fluid markers during early and late healing of intrabony defects after surgical treatment: a systematic review

BACKGROUND

Surgical treatments such as guided tissue regeneration (GTR) and access flap surgery are widely employed for the treatment of intrabony defects. However, little is known regarding the postoperative expression of gingival crevicular fluid (GCF) markers.

OBJECTIVE

The aim of this systematic review was to compare the expression of GCF markers following treatment of periodontal intrabony defects with guided tissue regeneration or access surgery. The association of the markers' expression with the clinical outcome was also assessed.

METHODS

An electronic literature search was conducted in MEDLINE, EMBASE, OpenGrey, LILACS and Cochrane Library up to December 2018 complemented by a manual search. Human, prospective clinical studies were identified. The changes from baseline up to 30 days (early healing) and 3 months (late healing) were assessed.

RESULTS

A total of 164 publications were identified and reviewed for eligibility. Of these, 10 publications fulfilled the inclusion criteria. The included studies evaluated 15 different GCF markers with a follow-up time between 21 and 360 days postoperatively. PDGF, VEGF and TIMP-1 changes were often investigated in the included studies; however, contrasting results were reported. Two studies agreed that both GTR and OFD lead to similar OPG level changes. TGF-β1 is increased early postoperatively, irrespective of the surgical technique employed.

CONCLUSION

There is limited evidence available on the expression of GCF markers after surgical interventions of intrabony periodontal defects. However, OPG and TGF-β1 tend to increase early post-operatively, irrespective of the surgical technique employed, irrespective of the surgical technique employed.

CLINICAL RELEVANCE

More well-designed, powered studies with sampling periods reflecting the regenerative process are needed, and future research should focus on employing standardised protocols for collecting, storing and analysing GCF markers.

Tissue engineering in periodontology: Biological mediators for periodontal regeneration

Teeth and the periodontal tissues represent a highly specialized functional system. When periodontal disease occurs, the periodontal complex, composed by alveolar bone, root cementum, periodontal ligament, and gingiva, can be lost. Periodontal regenerative medicine aims at recovering damaged periodontal tissues and their functions by different means, including the interaction of bioactive molecules, cells, and scaffolds. The application of growth factors, in particular, into periodontal defects has shown encouraging effects, driving the wound healing toward the full, multi-tissue periodontal regeneration, in a precise temporal and spatial order. The aim of the present comprehensive review is to update the state of the art concerning tissue engineering in periodontology, focusing on biological mediators and gene therapy.

CEMP-1 Levels in Periodontal Wound Fluid during the Early Phase of Healing: Prospective Clinical Trial

Objectives

Cementogenesis seems to be significantly compromised during tissue inflammation. In dental practice, surgical procedures are performed with the aim to regenerate periodontium including cementum. However, inflammation that occurs during the initial healing phases after surgery may impair regeneration of this tissues. The aim of the present study was to assess if surgical procedures designed to regenerate periodontium might affect levels of cementum protein-1 (CEMP-1) in periodontal wound fluid during early phase of healing.

Materials and Methods

In 36 patients, 18 intrabony periodontal defects were treated with regenerative therapy (REG group) and 18 suprabony periodontal defects were treated with open flap debridement (OFD group). In the experimental sites, gingival crevicular fluid was collected immediately before surgery, and periodontal wound fluid was collected 4, 7, 14, and 21 days after surgery. CEMP-1 levels were detected by indirect enzyme-linked immunosorbent assay technique.

Results

At the analysis, it resulted that there was a significant average difference in CEMP-1 values between the REG and OFD groups at baseline (p = 0.041), the CEMP-1-modeled average in the OFD group was lower by 0.45 ng/ml. There was a significant trend in CEMP-1 over time, and this trend was different among the 2 groups: the REG group showed a statistically significant rising CEMP-1 trend (0.18 ng/ml a week p = 0.012), while the OFD had a trend that was significantly lower (-0.22 ng/ml a week compared to the REG group trend p = 0.023), the OFD group lost on average 0.05 ng/ml a week. In REG sites, GCF protein levels resulted also related to clinical parameters.

Conclusions

During the initial inflammatory phase of periodontal healing, CEMP-1 levels decrease regardless of the surgical protocol applied. The surgical procedures used to regenerate periodontal tissue are able to reverse this trend and to induce significant increase of CEMP-1 in periodontal wound fluid after the first week postop.

Immunomodulatory Role of Stem Cells from Human Exfoliated Deciduous Teeth on Periodontal Regeneration

Periodontitis is initiated by the infection of periodontal bacteria and subsequent tissue inflammation due to immunoreaction, eventually leading to periodontal apparatus loss. Stem cells from human exfoliated deciduous teeth (SHEDs) have exhibited beneficial characteristics in dental tissue regeneration. However, the immunomodulatory functions of SHEDs have not been elucidated in the context of periodontitis treatment. In this study, we investigated the potential immunomodulatory effects of SHEDs on experimental periodontitis and demonstrated that multidose delivery of SHEDs led to periodontal tissue regeneration. SHEDs and monocytes/macrophages were cocultured in transwell systems and SHEDs were found to be capable of promoting monocyte/macrophage conversion to CD206⁺ M2-like phenotype. Bioluminescence imaging (BLI) was employed to assess the survival and distribution of SHEDs after delivery in periodontal tissues in an induced periodontitis model, and BLI revealed that SHEDs survived for ∼7 days in periodontal tissues with little tissue diffusion. Then, multidose SHED delivery was applied to treat periodontitis at 7-day intervals. Results showed that mutidose SHEDs altered the cytokine expression profile in gingival crevicular fluid, reduced gum bleeding, increased new attachment of periodontal ligament, and decreased osteoclast differentiation. Micro-computed tomography analysis showed SHED administration significantly increased periodontal regeneration and alveolar bone volume, and decreased distance of cementoenamel junction to alveolar bone crest. Furthermore, an increase in the number of CD206⁺ M2 macrophages was observed in periodontal tissues following the delivery of SHEDs, which aligned well with the promoted conversion to CD206⁺ M2-like cells from monocytes/macrophages in vitro after stimulation by SHEDs. This study demonstrated in a rat periodontitis model that local delivery of SHEDs attributed to the induction of M2 macrophage polarization, reduction of periodontal tissue inflammation, and enhancement of periodontal regeneration.