Effect of Foraminal Enlargement on Periapical Healing in Necrotic Teeth: A Systematic Review.

Introduction: Foraminal Enlargement (FE) is a cleaning performed in the apical-most region of the tooth, in order to optimize root disinfection. This systematic review evaluated the influence of FE during root canal treatment on bacterial reduction and repair of the periapical lesion. Materials and Methods: Searches in PubMed/MEDLINE, Scopus, Cochrane Library, Web of Science, Embase, Scielo, Lilacs and OpenGrey were performed until January-2024. Ex vivo and in vivo studies evaluating the effects of FE in the bacterial reduction and repair of the periapical lesion were included, respectively, followed by risk of bias assessment (modified version of Joanna Briggs Institute's for ex vivo studies and Systematic Review Centre for Laboratory animal Experimentation's risk of bias tools for in vivo studies). The meta-analysis was not feasible and a qualitative summary for each outcome was provided. Results: Of 950 studies, 2 in vivo studies were eligible, using animal models with infected teeth. Of these two, periapical repair was evaluated with hematoxylin-eosin stain, and FE improved periapical healing. Regarding ex vivo studies, 3 were eligible, using extracted human teeth. The inoculations in ex vivo models were performed with Enterococcus (E.) faecalis, and FE reduced E. faecalis in the ex vivo models. Conclusions: Foraminal enlargement seems to increase bacterial reduction within the root canal, and provide major periapical tissue repair on the histological analysis in animal studies. However, caution is necessary when translating these results to the clinical environment.

Comparison of different dual-wavelength photobiomodulation protocols application in third molar extractions. A split-mouth randomized controlled trial.

OBJECTIVE: To compare the use of PBMT in the soft tissue and bone healing after third molar extraction using the dual-wavelength laser directly into the post-extraction alveoli (PBMT-I), or PBMT with a red laser directly into the alveoli and with an infrared laser externally on the patient's face (PBMT-IE). METHODS: Twenty patients underwent extraction of four third molars were involved in this split-mouth double-blind randomized controlled trial. The Post-extraction alveoli were treated with the following protocols: PBMT-IE: Application of a red laser directly into the alveolus, and infrared laser irradiation transcutaneously and PBMT-I: Application of dual-wavelength laser intraorally. Patients were clinically evaluated 3, 7, 14, 30, and 90 days after the surgical procedure. The analyses in this study were divided into qualitative (centered on the patient's report and on the evaluators' analysis), and quantitative analyses (measurement of the vertical and horizontal dimensions of the face with the objective of measuring post-surgical edema and radiographic analyses for evaluation of the density and structure of the newly formed bone). RESULTS: A progressive improvement was observed in all parameters evaluated in this study, however, this improvement was time dependent, with no distinct effect observed between the PBMT treatments applied. CONCLUSION: The different dual-wavelength PBMT protocols induced a similar postoperative clinical course in third molar extraction surgeries, with a reduced occurrence of complications and a good healing pattern of hard and soft tissues.

Anti-inflammatory and healing effect of the polysaccharidic extract of Opuntia ficus-indica cladodes in cutaneous excisional wounds in rats.

This study aimed to investigate the anti-inflammatory and wound healing effects of the polysaccharide extract from Opuntia ficus-indica cladodes (TPL-Ofi) using a rat cutaneous wound model. After anaesthesia, four 7-mm-diameter dorsal wounds per animal (n = 6/group for each experimental day of evaluation) were created in female Wistar rats using a surgical punch. The animals were treated topically twice daily with TPL-Ofi (0.01-1%; treated group) or sterile saline (control group) for a period of 21 days. Ulcerated tissue was collected for analysis of histological parameters (inflammation score, number of polymorphonuclear, mononuclear, fibroblast/myofibroblasts and blood vessels), immunohistochemical (fibroblast growth factor 2 [FGF-2]) and oxidative stress markers (myeloperoxidase [MPO] and glutathione [GSH]). After 21 days of treatment, body weight, net organ weight and plasma biochemical levels were measured. TPL-Ofi, containing a total carbohydrate content of 65.5% and uronic acid at 2.8%, reduced oedema on the second day and increased the nociceptive threshold on the second and third days. TPL-Ofi reduced mononuclear infiltrate on the second and MPO activity on the fifth day. TPL-Ofi increased GSH levels on the second day, as well as fibroblast/myofibroblasts counts, neoangiogenesis and FGF-2 levels on the fifth and seventh days. No changes were observed in body weight, net organ weight or toxicology assessment. Topical application of TPL-Ofi exhibited anti-inflammatory and antinociceptive effects, ultimately improving wound healing in cutaneous wounds.

The Role of Plant Lectins in the Cellular and Molecular Processes of Skin Wound Repair: An Overview.

There is increasing pressure for innovative methods to treat compromised and difficult-to-heal wounds. Consequently, new strategies are needed for faster healing, reducing infection, hydrating the wound, stimulating healing mechanisms, accelerating wound closure, and reducing scar formation. In this scenario, lectins present as good candidates for healing agents. Lectins are a structurally heterogeneous group of glycosylated or non-glycosylated proteins of non-immune origin, which can recognize at least one specific monosaccharide or oligosaccharide specific for the reversible binding site. Cell surfaces are rich in glycoproteins (glycosidic receptors) that potentially interact with lectins through the number of carbohydrates reached. This lectin-cell interaction is the molecular basis for triggering various changes in biological organisms, including healing mechanisms. In this context, this review aimed to (i) provide a comprehensive overview of relevant research on the potential of vegetable lectins for wound healing and tissue regeneration processes and (ii) discuss future perspectives.

Bone Marrow Aspirate Matrix: A Convenient Ally in Regenerative Medicine.

The rise in musculoskeletal disorders has prompted medical experts to devise novel effective alternatives to treat complicated orthopedic conditions. The ever-expanding field of regenerative medicine has allowed researchers to appreciate the therapeutic value of bone marrow-derived biological products, such as the bone marrow aspirate (BMA) clot, a potent orthobiologic which has often been dismissed and regarded as a technical complication. Numerous in vitro and in vivo studies have contributed to the expansion of medical knowledge, revealing optimistic results concerning the application of autologous bone marrow towards various impactful disorders. The bone marrow accommodates a diverse family of cell populations and a rich secretome; therefore, autologous BMA-derived products such as the "BMA Matrix", may represent a safe and viable approach, able to reduce the costs and some drawbacks linked to the expansion of bone marrow. BMA provides -it eliminates many hurdles associated with its preparation, especially in regards to regulatory compliance. The BMA Matrix represents a suitable alternative, indicated for the enhancement of tissue repair mechanisms by modulating inflammation and acting as a natural biological scaffold as well as a reservoir of cytokines and growth factors that support cell activity. Although promising, more clinical studies are warranted in order to further clarify the efficacy of this strategy.

New Surgical Model for Bone-Muscle Injury Reveals Age and Gender-Related Healing Patterns in the 5 Lipoxygenase (5LO) Knockout Mouse.

Signaling lipid mediators released from 5 lipoxygenase (5LO) pathways influence both bone and muscle cells, interfering in their proliferation and differentiation capacities. A major limitation to studying inflammatory signaling pathways in bone and muscle healing is the inadequacy of available animal models. We developed a surgical injury model in the vastus lateralis (VL) muscle and femur in 129/SvEv littermates mice to study simultaneous musculoskeletal (MSK) healing in male and female, young (3 months) and aged (18 months) WT mice compared to mice lacking 5LO (5LOKO). MSK defects were surgically created using a 1-mm punch device in the VA muscle followed by a 0.5-mm round defect in the femur. After days 7 and 14 post-surgery, the specimens were removed for microtomography (microCT), histopathology, and immunohistochemistry analyses. In addition, non-injured control skeletal muscles along with femur and L5 vertebrae were analyzed. Bones were microCT phenotyped, revealing that aged female WT mice presented reduced BV/TV and trabecular parameters compared to aged males and aged female 5LOKO mice. Skeletal muscles underwent a customized targeted lipidomics investigation for profiling and quantification of lipid signaling mediators (LMs), evidencing age, and gender related-differences in aged female 5LOKO mice compared to matched WT. Histological analysis revealed a suitable bone-healing process with osteoid deposition at day 7 post-surgery, followed by woven bone at day 14 post-surgery, observed in all young mice. Aged WT females displayed increased inflammatory response at day 7 post-surgery, delayed bone matrix maturation, and increased TRAP immunolabeling at day 14 post-surgery compared to 5LOKO females. Skeletal muscles of aged animals showed higher levels of inflammation in comparison to young controls at day 14 post-surgery; however, inflammatory process was attenuated in aged 5LOKO mice compared to aged WT. In conclusion, this new model shows that MSK healing is influenced by age, gender, and the 5LO pathway, which might serve as a potential target to investigate therapeutic interventions and age-related MSK diseases. Our new model is suitable for bone-muscle crosstalk studies.

Influence of apical enlargement on the repair of apical periodontitis in rats.

AIM: To evaluate the influence of different apical enlargement protocols on the radiographic and histological healing of apical periodontitis in rats. METHODOLOGY: Apical periodontitis was induced bilaterally in the mandibular right and left first molars of 24 Wistar rats by pulp exposure to the oral cavity for 3 weeks. A standard serial root canal preparation technique was performed in the molar of one side, whilst the opposite side was the control group. Rats were randomly divided into three experimental groups (n = 8), according to the diameter of apical enlargement during root canal preparation: K-files size 20 (EG1), size 25 (EG2) and size 30 (EG3). Each animal was its own positive control, because the opposite arch remained untreated. Root canals were filled with a standard technique. After 3 weeks, the animals were euthanized. The main outcome of apical periodontitis healing was evaluated radiographically (mm2 ) and histologically (ordinal scores of inflammation) using a HE staining technique. The measurement of effect was obtained between the three experimental groups by carrying out generalized estimating equations, with Poisson regression with robust variance, pairing each experimental group with its respective control group within animals, adjusted for the mean within animal differences, with α = 5%. RESULTS: The mean and standard deviations of radiographic apical periodontitis size (mm2 ) and intensity of histological inflammatory scores were, respectively: EG1 (0.44 ± 0.27; 2.25 ± 0.46), EG2 (0.33 ± 0.10; 2.50 ± 0.53) and EG3 (0.22 ± 0.08; 2.63 ± 0.74). After 3 weeks, a significantly more favourable radiographic repair was observed when larger apical enlargement was performed (EG3), compared to EG1 and EG2 (P = 0.001). All experimental groups were associated with a significant difference on the radiographic and histological healing of apical periodontitis compared with its respective control group. CONCLUSION: Under the experimental conditions of this study, a larger apical enlargement protocol favoured a more rapid radiographic repair of apical periodontitis in rats after a 3-week follow-up.

Platelet-rich plasma reduces the oxidative damage determined by a skeletal muscle contusion in rats.

Platelet-rich plasma (PRP) has received increasing attention and is widely used in clinical practice in order to stimulate human tissue healing. Contusions are very common injuries observed in sports and affect the function of the musculoskeletal system. This study investigated the effects of PRP on the oxidative damage determined by a contusion induced in gastrocnemius muscle of rats. PRP was injected intramuscularly immediately after injury and every 48 h, and the biochemical analysis was performed 1, 3, 5, or 7 days after the contusion onset in order to evaluate the changes characteristics of the healing process. The contusion increased the levels of oxidative stress markers such as thiobarbituric acid reactive substances and oxidized dichlorofluorescein both in skeletal muscle tissue and erythrocytes preparations, and PRP treatment significantly reduced these oxidative damage markers. Furthermore, the contusion decreased the cellular viability in the site of the lesion and PRP was effective in diminishing this effect. Moreover, PRP increased the levels of enzymatic antioxidants superoxide dismutase and catalase activities in the injured muscle, and also the non-protein thiols (-SH) group levels in erythrocytes. In conclusion PRP, in the form that was used in this study, was able to modulate the oxidative damage determined by a classical skeletal muscle injury possibly by reducing the impairment of myocytes mitochondrial function and improving their endogenous antioxidant defense systems.

Efeitos do laser GaAlAs associado à microcorrentes na cicatrização por segunda intenção / Effects laser GaAlAs associated with microcurrent in the second intention healing

Introdução: A cicatrização de feridas é um processo dinâmico que envolve vários elementos celulares com propósito de restabelecer a funcionalidade do tecido lesado, muitos fatores podem interferir neste processo tornando-o complexo. O laser e a microcorrente são modalidades terapêuticas que otimizam o processo de reparo, porém são estudadas isoladas. Objetivo: Investigar a eficácia da associação da fototerapia (laser, GaAlAs, λ 656±5 nm) com a eletroterapia (microcorrente) na cicatrização por segunda intenção em ratos. Método: Foram utilizados 15 ratos submetidos à lesão dorsal direita com 8 mm de diâmetro divididos em três grupos (n=5), nominados de GC (controle), G2 (laser +30µA) e G3 (laser +160 µA). Para análises histopatológicas foi determinado p≤0,05. Resultados: A análise estatística revelou que a área de colágeno apresenta-se estatisticamente superior nos grupos tratados (G2 e G3) quando comparados com o grupo controle. Conclusão: A associação das modalidades induz ao aumento do colágeno na fase inicial do reparo tecidual.

Introduction: Wound healing is a dynamic process that involves multiple cellular elements with the purpose of restoring the functionality of the injured tissue. Many factors can interfere with this process, making it complex. Laser and microcurrent are therapeutic strategies that optimize the repair process, but have been studied in isolation. Objective: To investigate the efficacy of combining phototherapy (laser, GaAlAs, λ 656±5 nm) with electrotherapy (microcurrent) on second intention healing in rats. Methods: We used 15 rats with 8 mm in diameter lesions in the right dorsal. The rats were divided into three groups (n = 5): the CG (control group), G2 (laser+30µA) and G3 (laser +160µA). For histopathological analysis p ≤ 0.05 was determined. Results: Statistical analysis revealed that the area of collagen was statistically higher in the treated groups (G2 and G3) compared with the control group. Conclusion: A combination of methods induces increased collagen in the initial phase of tissue repair.

Zoledronic acid decreases gene expression of vascular endothelial growth factor and basic fibroblast growth factor by human epithelial cells.

Delayed wound healing in patients taking bisphosphonates could result from decreased expression of growth factors, which are directly related to cell proliferation and migration. In this study, we evaluated the gene expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) by epithelial cells exposed to zoledronic acid 5 µmol for 48 h using real-time polymerase chain reaction. The gene expression of VEGF and bFGF by epithelial cells exposed to zoledronic acid decreased by 34% and 51%, respectively (p=0.0001 and p=0.0001). We conclude that zoledronic acid can decrease the expression of growth factors by epithelial cells.