Dental resin monomers induce early and potent oxidative damage on human odontoblast-like cells.

Resin-based dental materials consist of filler particles and different monomers that are light cured in situ to re-establish dental function and aesthetics. Due to the degree of conversion of adhesive polymers, the monomers triethyleneglycol dimethacrylate (TEGDMA) and 2-hydroxyethyl methacrylate (HEMA) are released in relatively high amounts and are susceptible to degradation, acting as bioactive compounds and affecting cell and tissues. This study aimed to assess the effect of HEMA and TEGDMA exposure on metabolic activity, membrane integrity, and cell survival of human odontoblast-like cell (hOLCs). Exposure to resin monomers for 24 h induced major changes in cell membrane integrity, metabolic activity, and survival, which were measured by the calcein method and lactate dehydrogenase release. Increased and early reactive oxygen species (ROS) production was observed leading to degradative oxidation of membrane lipids identified as malondialdehyde production. Severe alteration in mitochondria occurred due to transmembrane mitochondrial potential collapse, possibly inducing activation of apoptotic cell death. hOLCs exposure to resin monomers modified the cell redox potential, with consequences on membrane permeability and integrity, including mitochondrial function. Lipid peroxidation appears to be a key phenomenon for the membrane structures oxidation after HEMA and TEGDMA exposure, leading to cell death and cytotoxicity. hOLCs respond early by differential induction of adaptive mechanisms to maintain cell homeostasis. Modulation of oxidative stress-induced response involves the regulation of genes that encode for antioxidant proteins such as catalase and heme oxygenase-1; regulation that functions as a critical protection mechanism against oxidative cell damage induced by HEMA and TEGDMA. Ascorbic acid as an antioxidant substance mitigates the oxidative damage associated with exposure to monomers.

The Rising Incidence of Allergic Contact Dermatitis to Acrylates.

BACKGROUND: Allergic contact dermatitis (ACD) caused by (meth)acrylates used in nail products is being increasingly reported in nail technicians and consumers. OBJECTIVES: The aim of the study was to assess the incidence of sensitization to (meth)acrylates in technicians and users of nail products with ACD, referred for patch testing in a tertiary center, during the last 10 years. METHODS: All patients with ACD, who reported a profession associated with cosmetic nail procedures or use of such services and were referred for patch tests in our department between January 2009 and December 2018, were identified. The incidence of positive sensitization to (meth)acrylates was assessed. RESULTS: Contact allergy to 1 or more (meth)acrylates was found in 116 (74.4%) of 156 nail technicians or nail product users, all women. One hundred thirty-eight (88.5%) were occupationally exposed, and 18 (11.5%) were consumers. In addition, there was a statistically significant increase in (meth)acrylate ACD during 2014-2018 (100/127 cases [79%]) when compared with 2009-2013 (16/29 cases [55%]). The most common sensitizer among the 156 allergic individuals was ethylene glycol dimethacrylate, which was positive in 113 cases (72.4%), and among patients with acrylate-positive patch test, the rate was 97.4%. CONCLUSIONS: Our experience confirms the worldwide changing landscape of rising (meth)acrylate sensitization in nail technicians and nail products users with ACD. Efforts to improve prevention are needed, and clinicians should have a high index for suspicion in this occupational group.

TEGDMA releasing in resin composites with different filler contents and its correlation with mitochondrial mediated cytotoxicity in human gingival fibroblasts.

Compositions of resin composite exhibit cytotoxicity, especially Triethylene-glycol-dimethacrylate (TEGDMA), yet the underlying mechanisms and its relationship with filler content are poorly understood. Here, specimens of five composites (VITA LC, VITA ZETA, Z350, Filtek P60, and AP-X), containing different filler size and weight, were immersed into culture medium for 72 h. After TEGDMA quantification, the resin composite eluates were used to incubate HGFs. Cellular viability was evaluated. Total reactive oxygen species (ROS) and mitochondrial ROS were detected to assess oxidative stress. Adenosine triphosphate and cytochrome c oxidase (CcO) activity, mitochondrial membrane potential and morphology, mitochondrial biogenesis regulators were analyzed to evaluate mitochondrial functions. Results showed that TEGDMA release negatively correlated to filler size and weight of tested composites. Although cell viability reduction was not significant, total and mitochondrial ROS production showed a positive relationship with the amount of TEGDMA in composite eluates. Furthermore, the expression of mitochondrial biogenesis markers and mitochondrial fusion protein, were markedly elevated in TEGDMA rich eluates, especially in VITA-LC group, shown as elongated mitochondrial morphology and aberrant mitochondrial functions. Overall, TEGDMA could elute easier from those resin composites with less filler content and cause oxidative stress in HGFs via mitochondria dysregulation. These data can be instructive to optimize the synthesis of resin composites from the perspective of biocompatibility. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1132-1142, 2019.

The dental resin monomers HEMA and TEGDMA have inhibitory effects on osteoclast differentiation with low cytotoxicity.

The dental resin monomers 2-hydroxyethyl methacrylate (HEMA) and triethylene glycol dimethacrylate (TEGDMA) are released from the resin matrix due to unpolymerized monomers; once released, they influence various biological functions and the viability of cells in the oral environment. Although HEMA and TEGDMA have various effects on cells, including inflammation, inhibition of cell proliferation or differentiation, and apoptosis, the effects of these monomers on osteoclasts remain unknown. In this study, we investigated the effects of HEMA and TEGDMA on osteoclast differentiation of bone marrow-derived macrophages or murine monocytic cell line RAW-D. Both HEMA and TEGDMA inhibited osteoclast formation and their bone-resorbing activity at non-cytotoxic concentrations. Moreover, HEMA and TEGDMA decreased the expression of nuclear factor of activated T cells cytoplasmic-1 (NFATc1), a master regulator of osteoclast differentiation, and of osteoclast markers that are transcriptionally regulated by NFATc1, including Src and cathepsin K. Regarding their effects on signaling pathways involved in osteoclast differentiation, HEMA impaired the phosphorylation of extracellular signal-regulated kinase and Jun N-terminal kinase, whereas TEGDMA attenuated the phosphorylation of Akt and Jun N-terminal kinase. Thus, HEMA and TEGDMA inhibit osteoclast differentiation through different signaling pathways. This is the first report on the effects of the monomers HEMA and TEGDMA on osteoclasts. Copyright © 2017 John Wiley & Sons, Ltd.

Skin penetration and dermal tolerability of acrylic nanocapsules: Influence of the surface charge and a chitosan gel used as vehicle.

For an improved understanding of the relevant particle features for cutaneous use, we studied the effect of the surface charge of acrylic nanocapsules (around 150nm) and the effect of a chitosan gel vehicle on the particle penetration into normal and stripped human skin ex vivo as well as local tolerability (cytotoxicity and irritancy). Rhodamin-tagged nanocapsules penetrated and remained in the stratum corneum. Penetration of cationic nanocapsules exceeded the penetration of anionic nanocapsules. When applied on stripped skin, however, the fluorescence was also recorded in the viable epidermis and dermis. Cationic surface charge and embedding the particles into chitosan gel favored access to deeper skin. Keratinocytes took up the nanocapsules rapidly. Cytotoxicity (viability<80%), following exposure for ≥24h, appears to be due to the surfactant polysorbate 80, used for nanocapsules stabilization. Uptake by fibroblasts was low and no cytotoxicity was observed. No irritant reactions were detected in the HET-CAM test. In conclusion, the surface charge and chitosan vehicle, as well as the skin barrier integrity, influence the skin penetration of acrylic nanocapsules. Particle localization in the intact stratum corneum of normal skin and good tolerability make the nanocapsules candidates for topical use on the skin, provided that the polymer wall allows the release of the active encapsulated substance.

Wear of acrylic cement (methylene-polymethacrylate) can manifest as extraosseous cement granuloma or false aneurysm of the popliteal artery after total knee arthroplasty.

Wear particles of acrylic cement, similar to other biomaterials, can cause periprosthetic osteolysis and formation of extraosseous cement granuloma (ECG). Expansive granuloma can manifest as a tumorous mass adjacent to the knee prosthesis, or it even can damage the popliteal artery and lead to false aneurysm formation. Suspicion of these two conditions requires a complex diagnostic approach and eventually revision of the endoprosthesis itself or reparation of the popliteal artery. Despite the beneficial fixative properties of acrylic cement (methylene-polymethacrylate), which are important for implantation of joint prostheses, the acrylic cement can also cause severe complications related to the wear process.

Injected nanoparticles: the combination of experimental systems to assess cardiovascular adverse effects.

When nanocarriers are used for drug delivery they can often achieve superior therapeutic outcomes over standard drug formulations. However, concerns about their adverse effects are growing due to the association between exposure to certain nanosized particles and cardiovascular events. Here we examine the impact of intravenously injected drug-free nanocarriers on the cardiovasculature at both the systemic and organ levels. We combine in vivo and in vitro methods to enable monitoring of hemodynamic parameters in conscious rats, assessments of the function of the vessels after sub-chronic systemic exposure to nanocarriers and evaluation of the direct effect of nanocarriers on vascular tone. We demonstrate that nanocarriers can decrease blood pressure and increase heart rate in vivo via various mechanisms. Depending on the type, nanocarriers induce the dilation of the resistance arteries and/or change the responses induced by vasoconstrictor or vasodilator drugs. No direct correlation between physicochemical properties and cardiovascular effects of nanoparticles was observed. The proposed combination of methods empowers the studies of cardiovascular adverse effects of the nanocarriers.

[Allergies to dental materials and effectiveness of treatment in the north-eastern region of Hungary]. / Fogászati anyagokkal szemben kialakuló allergiás megbetegedések és ellátásuk hatékonyságának vizsgálata az észak-alföldi régióban.

The recognition and treatment of allergy is a great challenge for all fields of medicine. The high prevalence of allergic reactions to dental materials and the related financial burden of their treatment make investigation of this disease very important. Our investigation was carried out on patients assigned to our outpatient department for dental allergy test between 1996 and 1998. We determined the distribution of gender and age among the allergic patients in the examined population. We also studied the prevalence of allergic reactions to different dental allergens and the distribution of dental allergens. In a follow-up study we determined the proportion of those patients, who were retreated in conformity with the results of epicutan tests and we followed up the positive effects of these treatments. We have found that dental allergy occurred five times more frequently in women (84%) than in men (16%) and the most affected age group was between 20 to 39 and 40-49 years (31%). Seventy-five percent of the patients suffered from a combination of metal and polymer allergy. The most frequent metal allergen was TEGDMA (triethylene glycol dimethacrylate) (49.7%). The suggested treatment plan was carried out in 63% of the allergic patients. The applied treatment was successful in 48% of these cases. We experienced that 48% of these patients got rid of their earlier signs and symptoms.

Involvement of mitochondrial signalling pathway in HGFs/S. mitis coculture response to TEGDMA treatment.

Although triethylene glycol dimethacrylate (TEGDMA), a resin monomer widely used in dental practice, has been shown to have cytotoxic effects on eukaryotic cells, little is known about how the oral environment influences the cytotoxicity of this biomaterial. The aim of this study was to evaluate eukaryotic cell reaction to TEGDMA in terms of the production of reactive oxygen species (ROS), the expression of Bax, the disturbance of mitochondrial membrane potential (MMP), and the occurrence of apoptosis in an in vitro coculture model of human gingival fibroblasts (HGFs) and Streptococcus mitis strain in presence of saliva. We found that S. mitis and saliva reduced the production of ROS (from 2.2 to 1.8 fold), the occurrence of apoptosis (from 11.3 to 4.7%), and the decrease of MMP (from 0.75 to 0.9 fold) induced by TEGDMA treatment. Addition of N-acetylcysteine, a well known antioxidant, improved cell viability in all experimental conditions. The results obtained in this study suggest that the presence of S. mitis and saliva in the periodontal environment could protect cells against TEGDMA toxicity. These results, shedding more light on the biological and molecular events that occur in conjuction with TEGDMA treatment in vitro in a coculture model that mimics the environment of the oral cavity, confirm the key role played by oral bacteria and saliva in preventing toxic events that can occur in vivo in HGFs.

Repeated dose toxicity study of Vibrio cholerae-loaded gastro-resistant microparticles.

CONTEXT: Microencapsulation of antigens has been extensively studied over the last decades aiming at improving the immunogenicity of vaccine candidates. OBJECTIVE: Addressing microparticles (MPs) toxicity in rats. MATERIAL AND METHODS: Spray-dried Eudragit® L 30 D-55 MPs and Eudragit® L 30 D-55 alginate MPs were elaborated and characterized. MPs obtained were administered to rats, three groups were defined: G1, control group; G2, administered with Vibrio cholerae (VC)-loaded MPs; G3, receiving VC-loaded alginate MPs. Animals received three vaccine doses. Body weight, food and water intake were controlled during the study. Haematological parameters, vibriocidal titres, organ weight and histology in necropsy were also analyzed. RESULTS: All animals grew healthy. Body weight gain, food and water intake and haematological parameters remained within physiological values, showing no treatment-related differences. Moreover, organ weight changes were not detected and animals developed protective vibriocidal titres. CONCLUSION: VC-loaded MPs and VC-loaded alginate MPs have proved to be safe and effective in the assessed conditions.

An orthodontic retainer preventing remission in celiac disease.

Celiac disease is a gluten enteropathy that is treated with dietary elimination of gluten. Exposure to nondietary sources of gluten, which are used in the manufacture of products such as plastics, dental equipment, and cosmetics, can also trigger or exacerbate disease. We report the case of a 9-year-old child who presented with nonspecific abdominal discomfort with abnormal serology for celiac disease. She underwent duodenal biopsies that revealed Marsh 3B histopathology. Despite strict dietary elimination of gluten, she continued to be symptomatic and demonstrate positive serum markers for active disease. It was then discovered that the child was exposed to gluten from her orthodontic retainer that contained a plasticized methacrylate polymer. Gluten is a common additive in plastics. She discontinued its use and demonstrated symptom resolution and complete normalization of serology. All possible sources of gluten, including nondietary, must be considered when managing a child with celiac disease.

Synthesis and characterization of noncytotoxic and biodegradable polymethacrylates-grafted chitosan gels.

Poly(methacrylates), namely 2-hydroxy ethyl methacrylate (HEMA), ethylene glycol dimethacrylate (EGDMA) and triethylene glycol dimethacrylate (TEGDMA) were grafted onto chitosan by using ceric ammonium nitrate as a redox initiator. Semi-IPN gels of chitosan-graft-poly(HEMA)-graft-poly(EGDMA) and chitosan-graft-poly(HEMA)-graft-poly(TEGDMA) were obtained. The grafting conditions were optimized with respect to monomer concentrations. The products were characterized by TGA, FTIR, XRD and SEM techniques. The solubility of the grafted products in aqueous medium decreased with increasing grafting percentage. The insoluble gels exhibited a highly pH sensitive swelling behaviour. TGA thermograms showed that poly(HEMA)/poly(TEGDMA)-grafted product is much more stable than poly(HEMA)/poly(EGDMA)-grafted product showing that TEGDMA is a more effective crosslinker than EGDMA. According to XRD analysis TEGDMA has a higher tendency to form ordered structures than EGDMA as it is capable of chain folding. The results of cytotoxicity studies revealed that the methacrylate-grafted chitosans were noncytotoxic and good candidates for biomedical applications.

Biology and cytotoxicity of dental materials: an in vitro study.

OBJECTIVE: The purpose of the experiment was to determine the degree of biocompatibility of a sealer (RO, laboratory made product) dental material in terms of cytotoxicity and animal tests. MATERIALS AND METHODS: In the present study, the biological compatibility of eight experimental composite materials was examined by in vitro methods. The bio-composites used for the cytotoxicity test were placed into direct contact with normal human fibroblasts in a cell-culture dish. After fibroblast bioassay was performed, a duplicate sample of biomaterial was placed in each well, and then the fibroblasts were incubated for 48 hours at 37°C and 5% carbon dioxide. Local reactions after the implantation of the material regarding preclinical evaluation have been carried out within the Biobase Laboratory of the "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania. The biocompatibility was studied using the tolerance test by the subcutaneous and intramuscular implantation of the cured specimens. RESULTS: The sealant C3 scored the highest value to the cell viability. The results of the present study showed that different dental materials had different effects on cells. The resin monomer TEGDMA, present in the sealer's composition, increased the amount of intracellular reactive oxygen species. Resin-based composites are cytotoxic before polymerization and immediately thereafter, whereas already set specimens cause almost no reaction. The test of tolerance showed that the composite materials do not contain any toxic, irritant substances or destructive ones for the living cells or tissues. CONCLUSIONS: The tests with experimental composite materials revealed that they are not cytotoxic for the living cells, in all versions of the materials used. All the samples of composite materials have maintained their integrity during the experiment, allowing the testing together with the embedded cells, which proved good viability, so they are suitable for dentistry use.

Assessing the biocompatibility of a dental composite product.

OBJECTIVE: The purpose of the study was to assess the biocompatibility of a composite material considering the reaction caused at the implant site during 21 days by daily observing the subjects' behavior as well as by macroscopic examination and histological examination upon expiry of the testing period. MATERIALS AND METHODS: We performed the tolerance test by implant of the composite material Dualcim. The implant test was made on two species of lab animals, Guinea pigs and Wistar rats in two versions: subcutaneous implant and intramuscular÷perimuscular implant. RESULTS: After a 21 days period, when the implant was in direct contact with the tissue, no change of the shape and consistency, color or surface of the implant occurred. Around the implants, the biocompatibility was kept under physiological limits. CONCLUSIONS: The product, in the structure and shape presented, could be easily placed under good conditions, both at the level of the subcutaneous tissue and at inter-muscular level. In case of both species and in all subjects, the histological exam proved a favorable development of the relationship between the implant body and the placing site.

Effects of ethanol and dimethyl sulfoxide on solubility and cytotoxicity of the resin monomer triethylene glycol dimethacrylate.

Several in vitro studies have reported contrasting values for triethylene glycol-dimethacrylate (TEGDMA) concentrations shown to induce cytotoxic effects. The aim of this study was to evaluate the effective concentrations of TEGDMA reached under the routine experimental conditions used in biocompatibility in vitro tests and determines changes in cytotoxicity and the associated production of reactive oxygen species (ROS) based on different TEGDMA solutions. TEGDMA was added to cell culture medium either directly or previously dissolved in dimethyl sulfoxide (DMSO) or ethanol (EtOH), both in the presence and absence of cells. Intracellular and extracellular TEGDMA concentrations were determined by high performance liquid chromatography (HPLC). The cytotoxicity effects of TEGDMA preparations were determined in 3T3-fibroblasts by 3-(4,5 dimethyiazol-2-1)-2-5-diphenyl tetrazolium bromide assay. The production of ROS was measured by flow cytometry. In the absence of cells the effective final TEGDMA concentrations obtained in Dulbecco's Modified Eagle Medium were significantly lower than the nominal one. When 2 mmol/L TEGDMA was first solubilized in DMSO or EtOH, a significant decrease in cell viability, and an increase in ROS production-compared to pure TEGDMA-was observed. After 2 h of incubation, TEGDMA previously dissolved in DMSO or ETOH was reduced by 15% and 20%, respectively, whereas otherwise it remained unaffected. Our results demonstrate that the effective concentration of TEGDMA dissolved in culture medium (in the presence or absence of solvents) does not concur with the nominal one. Therefore, the presence of the utilized solvents does not substantially alter the monomer solubility but eases its entrance into the cells thus improving its cytotoxic potency.

High frequency of false-positive reactions in attempted patch testing with acrylate/methacrylate mixes.

BACKGROUND: Although acrylate/methacrylate allergy has been frequently reported, until now patch testing with this group of allergens has been unwieldy, requiring the application of large supplementary series in most centres. OBJECTIVES: To formulate and evaluate two mixes of acrylate/methacrylate allergens in three centres (Malmö, Singapore, and Leuven). PATIENTS/MATERIALS/METHODS: All patients tested with the baseline series during the study period were also patch tested with the mixes. Mix 1 consisted of: triethyleneglycol diacrylate (TREGDA) 0.1% wt/wt, 2-hydroxyethyl methacrylate (2-HEMA) 1.0% wt/wt and ethyleneglycol dimethacrylate 1.0% wt/wt in petrolatum. Mix 2 consisted of: TREGDA 0.1% wt/wt and 2-HEMA 2.0% wt/wt in pet. The separate components of the two mixes were also tested simultaneously. RESULTS: There were 25 (5 males; 20 females) positive reactions to mix 1 with 16 in Malmö, 8 in Singapore, and 1 in Leuven. Positive reactions to mix 2 were seen only in Malmö, in 8 female patients. Thus, the positive reaction rate for mix 1 was 8.3% overall (Malmö 7.7%, Singapore 18.6%, and Leuven 2.1%), and that for mix 2 was 2.7% overall (Malmö 3.8%, Singapore 0%, and Leuven 0%). Of the 16 positive reactions to mix 1 in Malmö, only 4 were considered to be true allergic reactions, as the component allergen testing gave totally negative results in 12/16. For mix 2, only 3/8 positive reactions were considered to be true allergic reactions, as the component testing was negative in 5/8. Many doubtful (10-20%) and positive but non-allergic reactions were recorded, leading to early termination of the study. CONCLUSIONS: Although this was an unsuccessful attempt to formulate an acrylate/methacrylate mix, our experience will be useful for those embarking on future attempts to do this.

Glutathione level and genotoxicity in human oral keratinocytes exposed to TEGDMA.

Triethylene-glycol dimethacrylate (TEGDMA) is an important matrix comonomer used in many resin-modified dental materials. As the monomer-polymer conversion of these biomaterials is up to 80% at best, TEGDMA may leach into the oral cavity and the pulp in millimolar concentrations. Objective of this study was to evaluate whether TEGDMA is genotoxic in immortalized human oral keratinocytes (OKF6/TERT2), for example, due to formation of oxidative DNA-lesions. OKF6-TERT2 cells were exposed to TEGDMA at concentrations ranging from 0.5 mM to 5.0 mM. Cell viability was analyzed by the fluorescent probe propidium iodide (PI), intracellular levels of reactive oxygen species (ROS) were measured by 2',7'-dichlorofluorescein diacetate, whereas glutathione concentrations (GSH) were read using monobromobimane. Genotoxicity was determined quantitatively by the alkaline comet assay. To explore the presence of oxidized bases that could be produced by oxidative events during short-term treatment with TEGDMA, the 8-hydroxyguanine DNA-glycosylase 1 (hOGG1)-modified comet assay was used. TEGDMA induced an early and rapid GSH-depletion in a concentration-dependent manner (p < 0.05). A total of 5 mM TEGDMA reduced GSH to 57.8% ± 8.6% of control values already after 30 min. There was no significant reduction in cell viability during 6 h of incubation, and only moderate ROS-formation was detected after 4 h of treatment with TEGDMA. But after 24 h, TEGDMA-concentrations of ≥2.5 mM induced a significant reduction of total cell numbers and cells' viability. Furthermore, TEGDMA caused a concentration-dependent DNA damage in OKF6/TERT2 cultures, which was not associated with a detectable formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in the cellular genome. In conclusion, our results show that TEGDMA influences the intracellular redox metabolism and may exhibit pronounced cyto- and genotoxic effects in human immortalized oral keratinocytes. However, it may be concluded that oxidative stress is not causative for TEGDMA-dependent genotoxicity in these cells.

Polymethylmethacrylate-assisted ventral discectomy: rate of pseudarthrosis and clinical outcome with a minimum follow-up of 5 years.

BACKGROUND: Polymethylmethacrylate (PMMA) assisted ventral discectomy has been criticized for high rates of graft migration and pseudarthrosis when compared with various other fusion procedures for the treatment of cervical degenerative disc disease (DDD), therefore rendering it not the preferred choice of treatment today. Recently however spine surgery has been developing towards preservation rather than restriction of motion, indicating that fusion might not be necessary for clinical success. This study presents a long term comparison of clinical and radiological data from patients with pseudarthrosis and solid arthrodesis after PMMA assisted ventral discectomy was performed. METHODS: From 1986 to 2004 416 patients underwent ventral discectomy and PMMA interposition for DDD. The clinical and radiological outcome was assessed for 50 of 127 eligible patients after a mean of 8.1 years. Based on postoperative radiographs the patients were dichotomized in those with a pseudarthrosis (group A) and those with solid arthrodesis (group B). RESULTS: Pseudarthrosis with movement of more than 2 of the operated segment was noted in 17 cases (group A). In 33 cases no movement of the vertebral segment could be detected (group B). The analysis of the clinical data assessed through the neck disability index (NDI), the visual analogue scale (VAS) of neck and arm pain and Odom's criteria did not show any significant differences between the groups.Patients from group B showed a trend to higher adjacent segment degeneration (ASD) than group A (p = 0.06). This correlated with the age of the patients. CONCLUSIONS: PMMA assisted discectomy shows a high rate of pseudarthrosis. But the clinical long-term success does not seem to be negatively affected by this.