Resorption Process Research Articles

Incidence of Spontaneous Resorption of Lumbar Disc Herniation: A Meta-analysis.

A meta-analysis. This study aimed to analyze the incidence of spontaneous resorption of lumbar disk herniation (LDH) after conservative treatment. The resorption of intervertebral disks has been more frequently reported, but there is a lack of reference to the probability of resorption. We strictly refer to the standard established in the PRISMA (Preferred Reporting Items for a Systematic Review and Meta-analysis) statement, comprehensively searched electronic databases using the terms related to the spontaneous resorption of LDH. Two reviewers independently evaluated the potential studies, extracted, and analyzed the enrolled data. Thirty-one studies with 2233 patients who received conservative treatment were included for this analysis. We found that the pooled overall incidence of disk resorption was 70.39%, 87.77% for disk sequestration, 66.91% for disk extrusion, 37.53% for disk protrusion, and 13.33% for disk bugle, respectively. The resorption incidence in of 25%≤ reduction of disk herniation (RDH) 50%, RDH≥50%, and RDH=100% were 40.19%, 43.62, and 36.89%. The resorption incidence was 66.98% in Japan, 61.66% in the United States, 83.52% in Korea, 60.68% in China, 78.30% in the UK, 56.70% in Italy, and 83.68% in Turkey, respectively. Subgroup analysis showed that there was no significant difference in resorption incidence among prospective, retrospective studies and randomized controlled trials ( P =0.77), and there was no significant difference in evaluation method among qualitative and quantitative studies ( P =0.05). The existing evidence shows that the overall resorption incidence of LDH was 70.39%, the resorption incidence of ruptured LDH is higher than that of contained LDH. There are significant differences in the resorption incidence among countries. The resorption process mainly occurred within 6 months of conservative treatment.

The effect of peri-implant soft tissues on the stability of the sacral bone in the area of dental implants

Achieving the stability of bone tissue in the field of dental implants is still the most urgent and completely unsolved problem in implantological practice. Modern ideas about the biological principles of the structure and functioning of the tissues of the periimplant zone are one of the most significant factors in ensuring the stability of the crestal bone tissue. The soft-tissue component that forms the basis of the biological complex at the implant-suprastructure interface plays a key role in protecting the implant platform from non-physiological resorption processes.

Bone fractures in children with celiac disease: analysis of clinical and anthropometric measurements and bone metabolism markers

Introduction. Abnormal bone remodelling process is one of the clinical manifestations of celiac disease, which increases the risk of developing osteopenia conditions, including bone fractures. The median age for the first fracture is similar in celiac disease and in the general population, but the incidence is higher in patients with celiac disease.Aim. To compare clinical and anamnestic characteristics, anthropometric measurements and laboratory test results in celiac children and adolescents with and without bone fractures.Materials and methods. A total of 151 children aged 1-17 years were included in the study. Patients were divided into two groups: those who had fractures in their lifetime - 21 (13.9%) children and those who had no fractures - 130 (86.1%) children. Results. The frequency of fractures among the patients included in the study was 13.9%, while among children with vitamin D deficiency fractures were reported 2.7 times more often than among children with its optimal level (p = 0.019).Vitamin D deficiency was detected in 20 (95.2%) children with fractures, and levels of 30 ng/ml or higher were found in 1 (4.8%) child. In the group of patients without fractures, the 25(OH)D optimal level was observed in 43 (33.1%) cases.It was found that patients with fractures had a significantly lower osteocalcin level than children without fractures - 26.9 (15.6; 32.9) ng/ml (p < 0.001), and children with fractures had C-terminal telopeptide level 1.9 times higher than the group of children without fractures (p = 0.01). The median PTH concentration in children with fractures was 34.6 (19.6; 54.7) pg/ml, whereas in children without fractures it was 24.2 (17.1; 39.5) pg/ml (p = 0.1).Conclusion. Due to elevated PTH level and severe vitamin D deficiency, a predominance of osteoresorption over osteosynthesis was observed in children with celiac disease and fractures of tubular bones. It is important to maintain a 25(OH)D optimal level and monitor biochemical markers of bone metabolism in patients with celiac disease to assess the processes of bone formation and resorption.

Lipid Peroxidation as a Possible Factor Affecting Bone Resorption in Obese Subjects-Preliminary Research.

Oxidative stress, which promotes bone catabolism, also affects the quality of bone tissue. We aimed to assess the impact of metabolic disorders and oxidant-antioxidant imbalance associated with primary obesity on bone resorption and formation processes. Anthropometric parameters, metabolic variables, oxidative stress indicators (malondialdehyde, vitamins A and E, uric acid, superoxide dismutase, catalase, glutathione peroxidase, type 1 paraoxonase, iron-reducing plasma antioxidant power) and markers of bone turnover (type I procollagen N-terminal propeptide and the type I collagen C-terminal cross-linked telopeptide; P1NP and CTX) were assessed in 108 Polish participants. Under the influence of oxidative stress, both enzymatic and non-enzymatic defense mechanisms were stimulated in obese subjects, especially in women, who had increased lipid peroxidation and activity of catalase (particularly in first-degree obesity) and decreased vitamin E concentration. The process of lipid peroxidation, as well as the weakening of the bone formation, was strongly manifested in women at a BMI range of 35.0-39.9 kg/m2 but not at BMI > 40.0 kg/m2, but it had a comprehensive negative impact on bone turnover in obese men. Obesity and its degree of advancement significantly affected the decrease in the concentration of the marker of bone formation-P1NP-only in the plasma of women. Excessive body weight had no effect on the value of the bone resorption marker in plasma, regardless of gender. Our results confirm the existence of the "obesity paradox" in the aspect of bone tissue metabolism and suggest that a specific body weight threshold changed the molecular response of the tissue.

Clinical masks of marble disease

Marble disease, or osteopetrosis (OPT), is rare in the practice of a rheumatologist, internist or pediatrician. This group of hereditary diseases is based on a defect in the formation, development and functioning of osteoclasts (OCL), which leads to disruption of the processes of resorption and remodeling of bone tissue. Disturbance of resorption leads to increased density and changes in the quality of the bones, as a result of which they become more fragile. As a rule, the disease manifests with pathological fractures. In recent decades, 70% of patients with OPT have been found to have mutations in at least 10 genes that lead to impaired functioning of the OCL. Depending on the variant of inheritance, autosomal dominant, autosomal recessive and intermediate types of OPT are distinguished. Autosomal dominant OPT has a benign course that can be asymptomatic or characterized by multiple bone fractures and other spinal anomalies. The disease usually manifests in adulthood or adolescence. Life expectancy in patients of this group does not differ from that in the general population. Malignant, or infantile, OPT is associated with an autosomal recessive inheritance pattern. Its clinical manifestations are observed from the moment of birth, without treatment, patients die within the first decade of life. In such patients, in addition to the skeletal pathology, there is involvement of the hematopoietic system, compression of the cranial nerves and their function disturbance.The article presents a clinical case of autosomal dominant OPT diagnosed in adulthood (at the age of 38), when the patient referred to the doctor for the first time. Differential diagnosis with ankylosing spondylitis and paraneoplastic spondyloarthritis was performed.

Joint damage in patients with COVID-19 in family medicine

Rheumatoid pathology of the articular apparatus is a significant social problem due to the high incidence of disability. Cases of the development of arthropathy after SARS-CoV-2 infection have been described. The basis of the pathogenesis of this condition may be the excessive synthesis of pro-inflammatory cytokines (cytokine storm), which is characteristic of the acute course of COVID-19. In patients with a severe form of the coronavirus infection, a high concentration of a number of cytokines IFN-γ, IL-1, IL-6, IL-12, and TGFβ was observed. Due to the activation of osteoclasts, resorptive processes in bone tissue were significantly enhanced. Autoimmunization due to cross-reactivity of the virus can also lead to joint damage. Reactive arthritis tends to be acute and occurs in the form of monoarthritis or oligoarthritis. The pathological process develops mainly in the joints of the wrist, ankles, and small joints of the distal parts of the limbs.

Changes in Pulp and Roots of Deciduous Teeth during Different Stages of Physiologic Resorption: A Histologic Study.

Resorption of primary teeth and eruption of permanent teeth involves a complex series of changes. The cellular and histological changes occurring during the process of resorption vary stagewise. The knowledge of the changes occurring in the pulp of deciduous teeth would provide information about the resorptive process. To evaluate the histologic changes of the pulp of deciduous teeth related to different stages of physiologic root resorption. To establish the cause and effect relationship, a contrived histologic study design was planned. A total of 60 extracted deciduous incisors, canines, and molars were included in the study. The remaining root length (RRL) was determined based on the standardized photographs. The teeth were then grouped into three based on the percentage of RRL. The teeth were subjected to decalcification with 5% nitric acid, following which histological processing was performed. The present study being a qualitative study design, descriptively explains the histologic findings, and no statistical tests have been applied. During the initial stages of resorption, there were no histological alterations noted in the pulp, particularly in the cervical 3rd, with the cellular structure relatively maintained. As the resorption progresses, reversal lines were evident, indicating a process of repair occurring simultaneously during the process of resorption. With further advancement, the repair is overtaken by the resorption indicated by the presence of resorptive cells. Neovascularization and an increase in immune cells are also evident in advanced stages. The pulp exhibits progressive changes as the resorption continues from stage I to stage III. The changes vary from a smaller number of immune cells and odontoclasts in stage I to increasing number of the same as resorption progresses. Murthy P, Bhojraj N, Hegde U. Changes in Pulp and Roots of Deciduous Teeth during Different Stages of Physiologic Resorption: A Histologic Study. Int J Clin Pediatr Dent 2023;16(3):437-443.

Remodelling of mandibular condylar head after fixation of fractures with ultrasound activated resorbable pins: A retrospective case series

The aim of this study was to assess whether the resorption of poly-lactic acid pins, used for condylar head fracture fixation, adversely affect remodelling of the condylar head.A retrospective review of patients was performed that underwent ORIF of CHF with ultrasound activated resorbable poly-lactic acid pins and had CT/CBCT scans of the condyle at least 18 months after surgery, at which point the fixation material was expected to be resorbed. We reviewed the size, shape and position of the condylar head and compared this to the normal side and compared this to the results of conservative management and ORIF with titanium screws in the literature.Most patients had condylar heads normally positioned and shaped, with minimal bone changes. The position of the condyle in the fossa, its shape and bone changes compare favourably with previous studies on CHF managed conservatively or with titanium screw fixation. There was no radiographic evidence of the pins after 18 months.In conclusion, ultrasound activated resorbable pins can provide suitable fixation for ORIF of condylar head fractures, avoiding the need for screw removal, and there was no evidence that the resorption process adversely affected the remodelling of the condylar head.

X-ray diffraction studies of a partially demineralized oriented cortical bone with the controlled depth of analysis

The in vitro demineralization of bone tissue is used for simulating the osteoporosis related bone loss. This way would be helpful in observations of bone apatite dissolution in microstructural level and may give significant input for understanding crystal-chemistry of bone resorption. In the case of cortical bone, demineralization occurs inhomogeneously, with the formation of a superficial demineralized layer and a transition zone with a gradient of concentration and structural characteristics perpendicular to the reaction advance front. Changes in the microstructural parameters of the bone mineral in this interface zone are of great interest for understanding the resorptive processes in the bone associated with osteoporosis. In this work, the SEM-EDX method was used to estimate the sizes of the demineralized and interface layers in the cortical bone during stepwise demineralization in HCl water solution; the general patterns of changes in the concentrations of Ca, P, and Cl in these layers were established. The calculations of the effective penetration depth of X-rays in diffraction mode for the intact and partially demineralized cortical bone were performed. It is shown that the use of CoKα radiation (instead of the usual CuKα) ensures the depth of probing within the interface zone, which allows to adequately assess the microstructural parameters (crystallite sizes and lattice microdeformations) of altered bioapatite in the zone of its interaction with an acid agent. A nonmonotonic change in the average size of crystallites and microdeformations of the apatite lattice was revealed during acid demineralization of the bone. Using asymmetric XRD geometry, the evidence was obtained that the affected mineral of the transition zone does not contain other crystalline phases except for weakly crystallized apatite. For the first time, the depth-controlled XRD analysis was applied to such a complex (surface-gradient) object as partially demineralized cortical bone. Additionally, we propose a rapid, averaging, and non-destructive method for estimating the depth of the reaction front dividing the demineralized and non-demineralized portions of the bone by XRD. The consistency of XRD and SEM-EDX data on the thickness values of the demineralized layer is shown.

Multi-scale characterization of the spatio-temporal interplay between elemental composition, mineral deposition and remodelling in bone fracture healing

Bone mineralization involves a complex orchestration of physico-chemical responses from the organism. Despite extensive studies, the detailed mechanisms of mineralization remain to be elucidated. This study aims to characterize bone mineralization using an in-vivo long bone fracture healing model in the rat. The spatio-temporal distribution of relevant elements was correlated to the deposition and maturation of hydroxyapatite and the presence of matrix remodeling compounds (MMP-13). Multi-scale measurements indicated that (i) zinc is required for both the initial mineral deposition and resorption processes during mature mineral remodeling; (ii) Zinc and MMP-13 show similar spatio-temporal trends during early mineralization; (iii) Iron acts locally and in coordination with zinc during mineralization, thus indicating novel evidence of the time-events and inter-play between the elements. These findings improve the understanding of bone mineralization by explaining the link between the different constituents of this process throughout the healing time. Statement of significanceBone mineralization involves a complex orchestration of physico-chemical responses from the organism, the detailed mechanisms of which remain to be elucidated. This study presents a highly novel multi-scale multi-modal investigation of bone mineralization using bone fracture healing as a model system. We present original characterization of tissue mineralization, where we relate the spatio-temporal distribution of important trace elements to a key matrix remodeling compound (MMP-13), the initial deposition and maturation of hydroxyapatite and further remodeling processes. This is the first time that mineralization has been probed down to the nanometric level, and where key mineralization components have been investigated to achieve a comprehensive and mechanistic understanding of the underlying mineralization processes during bone healing.

Management of external cervical resorption with internal approach: 18 months of follow-up

Introduction: External cervical resorption (ECR) in advance stages may have a probable pulp involvement. In some of these cases, the accessibility of the resorptive process can be performed by an intraradicular approach. Aim: To report the management of an ECR, classified as Class 2cp according to Patel classification, with an internal approach. Case report: A 22-year-old male patient presented a complaint of dentin hypersensitivity related to left maxillary lateral incisor and reported a history of previous dental trauma. Based on the clinical, radiographic and tomographic findings, the left maxillary lateral incisor was diagnosed as symptomatic irreversible pulpitis with ECR class 2cp of Patel classification. The patient was scheduled for endodontic treatment, with an internal approach, and repair of the resorbed area. Intracanal dressing of calcium hydroxide paste was used in the root canal and resorption gaps. The root canal filling was performed in two steps: obturation of the apical and middle third with gutta-percha by lateral condensation technique and obturation of the cervical third and filling the resorbed area with MTA. After 18 months signs and symptoms compatible with success were observed, and the tomographic and radiographic images suggested a successful endodontic treatment and evolutionary process of repair of bone and mineralized dental tissues. Conclusion: Patel class 2cp ECR treatment through an internal approach, including conventional endodontic treatment and recovery of the reabsorbed area with calcium hydroxide and MTA is a viable treatment option, but may cause tooth discoloration.

Nutrient stoichiometric and resorption characteristics of the petals of four common urban greening Rosaceae tree species.

Nutrient resorption efficiency and stoichiometric ratios are important strategies for understanding plants. The present study examined whether or not the nutrient resorption process of plant petals is similar to that of leaves and other vegetative organs, as well as the nutrient restriction status of the whole flowering process of plants in urban ecosystems. Four Rosaceae tree species, Prunus yedoensis Matsum, Prunus serrulata var. lannesiana, Malus micromalus Makino, and Prunus cerasifera 'Atropurpurea', were selected as urban greening species to analyze the contents of C, N, P, and K elements in the petals and their stoichiometric ratios and nutrient resorption efficiencies. The results show interspecific differences in nutrient contents, stoichiometric ratios, and nutrient resorption efficiency of the fresh petals and petal litter of the four Rosaceae species. The nutrient resorption process was similar to that of the leaves before the petals fell. The nutrient contents of petals were higher than that of leaves at the global level, but the stoichiometric ratio and nutrient resorption efficiency of petals were lower. According to the "relative resorption hypothesis", N was limiting during the entire flowering period. The nutrient resorption efficiency of petals was positively correlated with nutrient variation. The correlation between the nutrient resorption efficiency of petals with nutrient content and stoichiometric ratio of petal litter was stronger. The experimental results provide scientific basis and theoretical support for the selection, scientific maintenance and fertilization management of Rosaceae tree species in urban greening.

Evaluation of awareness and knowledge regarding mandibular reconstruction in interns and postgraduates: A cross-sectional study

Objectives: Many conditions such as malignancy, osteomyelitis, osteonecrosis, or osteoradionecrosis affect oral cavity particularly the jaw by impairing the bone formation and resorption process. Eradication of these conditions may sometimes require resection of whole of jaw bone or a part of it. Reconstruction or rehabilitation of the lost part is necessary for higher quality of life. Hence, it is important to bring this topic to limelight and evaluate the level of knowledge. Furthermore, it is important to assess awareness present among interns and postgraduates (PGs) for the reconstruction techniques. The overarching aim of this study was to conduct a survey to evaluate the awareness and knowledge regarding different mandibular reconstruction among interns and PGs. Materials and Methods: An online questionnaire-based study using Google forms was carried out among interns and PGs of VSPM’s dental college and research center. General characteristics, designation, reconstruction techniques, goals and criteria for reconstruction, grafts, and classification of defects were assessed. Results: A total of 100 participants participated in the survey. About 50% among them were interns and 50% were PG students. About 92% of PG participants were aware about the different mandibular techniques, while among the interns only 88% were aware. Conclusion: A significant difference existed in responses collected from interns and postgraduate. PG students were more aware about the reconstruction and rehabilitation options. Further, upgradement of technologies in this field can improve quality of life of cancer patients and dentist can help to provide it. Knowledge and attitude toward rehabilitation can improve the promptness of delivery of health services.

SIGNIFICANCE OF VARIABILITY OF ANATOMICAL AND TOPOGRAPHIC FEATURES OF THE MANDIBULAR CANAL(S) IN CLINICAL DENTISTRY

Abstract. This paper presents arguments about the possible iatrogenic eff ect during odontological or reconstructive surgical interventions on the dental- maxillary system, taking into account the morphological variability and topography of the mandibular canal(s) while maintaining the functionality of its (their) morphological structures.The aim of the study is to substantiate the necessary understanding of the peculiarities of morphological variants and laying the mandibular canal(s) in order to preserve the morphological and functional properties of its (their) structures during dental conservative and surgical interventions.Material and Methods. The screening of 1000 digital segmental records of X-ray examinations of the human lower jaw aged 25-75 years was conducted, and 58 of them were identifi ed, refl ecting the iatrogenic eff ect on its foliar morphological structures.Results and Discussion. Due to its mechanical and long-term chemical action, odontological iatrogenicity is characterized by twofold pathoetiological signs of infl uence on periapical and adjacent morphological formations. During mechanical action, the primary pathological manifestation is ischemia, in this case of the neurovascular bundle, with varying degrees of damage, which will later be refl ected in the reversible or irreversible, or conditionally reversible (anastomosing) recovery. In the case of chemical action, there are manifestations of destructive changes with a progressive degree of necrosis, depending on the origin and concentration of the etiological factor, which in most cases, becomes irreversible. Pathological processes and atrophy of the mandibular bone tissue caused by the loss of the masticatory group of teeth reduce the diagnostic diff erentiation of the anatomical and topographic features of the mandibular canal(s).Conclusions. Misunderstanding of individual anatomical variants and topography of the mandibular canal(s) during X-ray examinations to plan dental surgical interventions leads to damage to its morphological structures. Any traumatization of the neurovascular bundle laid in the mandibular canal(s) is expressed by proprioreceptive disorders in the areas of its innervation, primarily infl ammatory- resorption processes, due to a violation of their nutrition. The degree of iatrogenicity depends on the aggressiveness of the pathoetiological factor and the summation of its action over time, as well as on the morphology of the mandibular canal system, which can take on the function of «relative compensation»

Antipsychotic-induced bone loss: the role of dopamine, serotonin and adrenergic receptor signalling.

Antipsychotics are commonly used in treating psychiatric disorders. These medications primarily target dopamine the serotonin receptors, they have some affinity to adrenergic, histamine, glutamate and muscarinic receptors. There is clinical evidence that antipsychotic use decreases BMD and increases fracture risk, with dopamine, serotonin and adrenergic receptor-signalling becoming an increasing area of focus where the presence of these receptors in osteoclasts and osteoblasts have been demonstrated. Osteoclasts and osteoblasts are the most important cells in the bone remodelling and the bone regeneration process where the activity of these cells determine the bone resorption and formation process in order to maintain healthy bone. However, an imbalance in osteoclast and osteoblast activity can lead to decreased BMD and increased fracture risk, which is also believed to be exacerbated by antipsychotics use. Therefore, the aim of this review is to provide an overview of the mechanisms of action of first, second and third generation antipsychotics and the expression profiles of dopamine, serotonin and adrenergic receptors during osteoclastogenesis and osteoblastogenesis.

Assessment of the Orthodontic External Resorption in Periodontal Breakdown-A Finite Elements Analysis (Part I).

This Finite Elements Analysis (FEA) assessed the accuracy of Tresca failure criteria (maximum shear stress) for the study of external root resorption. Additionally, the tooth absorption-dissipation ability was assessed. Overall, 81 models of the second mandibular premolar, out of a total of 324 simulations, were involved. Five orthodontic movements (intrusion, extrusion, rotation, translation, and tipping) were simulated under 0.6 N and 1.2 N in a horizontal progressive periodontal breakdown simulation of 0-8 mm. In all simulations, Tresca criteria accurately displayed the localized areas of maximum stress prone to external resorption risks, seeming to be adequate for the study of the resorptive process. The localized areas were better displayed in the radicular dentine-cementum component than in the entire tooth structure. The rotation and translation seem prone to a higher risk of external root resorption after 4 mm of loss. The resorptive risks seem to increase along with the progression of periodontal breakdown if the same amount of applied force is guarded. The localized resorption-prone areas follow the progression of bone loss. The two light forces displayed similar extensions of maximum stress areas. The stress displayed in the coronal dentine decreases along with the progression of bone loss. The absorption-dissipation ability of the tooth is about 87.99-97.99% of the stress.

Ekspresi BMP2 dan TRAF6 pada Jaringan Periodontal setelah Pemberian Ekstrak Kopi Robusta selama Pergerakan Gigi Ortodonti

Orthodontic tooth movement occurs due to mechanical stimulation followed by alveolar bone and periodontal ligament remodeling. Bone remodeling is the process of bone resorption in areas of tension and bone formation in areas of tension. Various techniques and drugs are used to speed up orthodontic treatment. This study aims to analyze the expression of BMP2 and TRAP6 on orthodontic tooth movement after the administration of Robusta coffee extract. Twenty-four Wistar rats were divided into 4 groups: C1 (2 weeks) and C2 (3 weeks) groups: rats were given orthodontic mechanical force (OMF) and T1 (2 weeks) and T2 (3 weeks) groups rats were given OMF and Robusta coffee extract. OMF in rats was performed by moving the maxillary right permanent molars mesially with a Niti closed coil spring. Observations were made on the 15th and 22nd day by immunohistochemical examination to determine the expression of BMP2 and TRAP6. Administration of Robusta coffee extract for 2 weeks and 3 weeks increased BMP2 and TRAP6 expression (p <0.05). Administration of Robusta coffee extract increased the expression of BMP2 and TRAP6 in the alveolar bone during orthodontic tooth movement.

Comment on the Article: Subretinal Bleb of Voretigene Neparvovec.

To the Editor: We studied with great interest the article Subretinal Bleb of Voretigene Neparvovec by João Pedro Marques et al.1 Demonstrating new ways of sub-retinal bleb formation in the process of voretigene neparvovec application provides important upgrades of the surgical technique.1 However, we would like to address some potential bias of the surgical protocol that may confound the final outcomes and propose an alternate approach based on our own experience. We hypothesize that performing only one bleb in the process of subretinal voretigene application, following a saline prebleb, could lead to perifoveal chorioretinal atrophy. Utilizing saline in the process of pre-bleb formation, dilutes the concentration of the vector and possibly lowers the risk of toxicity2 but calls the efficacy in question on the other hand. The concept of creating only a single bleb and accordingly, instilling the total volume of the drug subretinally, carries a higher risk of foveal rupture due to uncontrolled and excessive retinal stretching. Furthermore, completely detached fovea could be mis-located during the ensuing process of subretinal voretigene neparvovec resorption. Thus, to deliver the total amount of the prescribed volume, it seems rational to distribute it to more than a single bleb. Performing more than one bleb lowers the volume of voretigene neparvovec within a single bleb, and additionally, prevents the detachment of the fovea. Finalization with a fluid-air exchange in the vitreous cavity provides both tamponade and allows a gentler and more favorable subretinal spreading of the drug into the subfoveal space compared to dynamically robust separation of the retinal neuroepithelium by subretinal instillation of the total drug volume in a single shot either manually or by subretinal injector with viscous fluid injection. Leon Marković, MD*† Damir Bosnar, MD, PhD*†‡ Mirjana Bjeloš, MD, PhD*†‡

The role of trace elements in the pathomorphology of destructive forms of periodontitis of an infectious nature

Aim. To study and analyze the role of trace elements in pathomorphological changes occurring in teeth with destructive forms of apical periodontitis in the acute stage by means of light and electron microscopy.Materials and methods. Pathological changes were studied on 46 teeth with destructive forms of periodontitis in the acute stage using an Olympus BX-40 light microscope. Scanning electron microscopy was used to conduct X-ray microanalysis of 10 teeth.Results. The infiltration of the inflammatory focus is an indirect evidence of a change in the balance between the production of oxygen radicals by phagocytic cells in destructive forms of periodontitis and their elimination, which includes multifaceted interrelated factors, namely, direct damage to biomolecules, increased signaling of the nuclear factor, and cell death. The increased amount of studied chemical elements in the tissues of teeth with apical forms of periodontitis during the period of exacerbation allows us to assume that oxygen can become a source of free radicals and stimulate the process of resorption of the tooth root.Conclusions. Cellular infiltration found in biopsy specimens of teeth with destructive forms of periodontitis in the acute stage, as well as an increased content of trace elements in dental tissues, suggests that this contributes not only to loss of bone mass in the periapical space, but also leads to the destruction of apical tissues. Trace elements are biomarkers of oxidative stress. Treatment should be aimed at accelerating the restoration of oxidative balance.

Endodontic tooth treatment with internal root resorption: case report

INTRODUCTION: Internal tooth resorption is characterized by the destruction of dentin in the root canal wall due to an imbalance of clastic cell activity resulting mainly from trauma. Thus, endodontic treatment is indicated with the aim of removing the etiology of resorption by using intracanal medication to combat possible infection and thus provide tissue repair. OBJECTIVE: The aim of this study is to investigate the treatment of root resorption by conventional endodontic therapy by identifying internal resorption and highlighting the steps of endodontic treatment. CASE REPORT: The methodology adopted was a clinical study in which we selected a female patient who required endodontic treatment of tooth 12 with pulp necrosis and resorption in the middle third of the root. Thus, the endodontic treatment was performed according to the technique, through instrumentation of the root canal followed by irrigation with sodium hypochlorite 6%. After instrumentation, the PUI (Ultrasonic Passive Irrigation) was performed followed by irrigation with 6% sodium hypochlorite and EDTA solution. The root canal was also dried and filled, allowing the respective tooth to be provisionally restored with glass ionomer so that it could later be permanently restored according to the indication of the material. Therefore, internal tooth resorption causes irreversible damage to the individual, such as tooth loss, thus altering the functioning of the stomatognathic system. Thus, endodontic treatment has great advantages in the treatment of teeth with internal tooth resorption since it promotes stagnation of the resorption process and tissue repair. CONCLUSIONS: Therefore, the treatment of internal tooth resorption requires close attention by the dental surgeon due to careful evaluation throughout the entire clinical case.