Sparassis latifolia and exercise training as complementary medicine mitigated the 5-fluorouracil potent side effects in mice with colorectal cancer: bioinformatics approaches, novel monitoring pathological metrics, screening signatures, and innovative management tactic.

BACKGROUND: Prompt identification and assessment of the disease are essential for reducing the death rate associated with colorectal cancer (COL). Identifying specific causal or sensitive components, such as coding RNA (cRNA) and non-coding RNAs (ncRNAs), may greatly aid in the early detection of colorectal cancer. METHODS: For this purpose, we gave natural chemicals obtained from Sparassis latifolia (SLPs) either alone or in conjunction with chemotherapy (5-Fluorouracil to a mouse colorectal tumor model induced by AOM-DSS. The transcription profile of non-coding RNAs (ncRNAs) and their target hub genes was evaluated using qPCR Real-Time, and ELISA techniques. RESULTS: MSX2, MMP7, ITIH4, and COL1A2 were identified as factors in inflammation and oxidative stress, leading to the development of COL. The hub genes listed, upstream regulatory factors such as lncRNA PVT1, NEAT1, KCNQ1OT1, SNHG16, and miR-132-3p have been discovered as biomarkers for prognosis and diagnosis of COL. The SLPs and exercise, effectively decreased the size and quantity of tumors. CONCLUSIONS: This effect may be attributed to the modulation of gene expression levels, including MSX2, MMP7, ITIH4, COL1A2, PVT1, NEAT1, KCNQ1OT1, SNHG16, and miR-132-3p. Ultimately, SLPs and exercise have the capacity to be regarded as complementing and enhancing chemotherapy treatments, owing to their efficacious components.

System biology analysis to develop diagnostic biomarkers, monitoring pathological indexes, and novel therapeutic approaches for immune targeting based on maggot bioactive compounds and polyphenolic cocktails in mice with gastric cancer.

Early diagnosis and prognosis are prerequisites for mitigating mortality in gastric cancer (GaCa). Identifying some causative or sensitive elements (coding RNA (cRNA)-non-cRNAs (ncRNAs)) can be very helpful in the early diagnosis of GaCa. Notably, despite significant development in the GaCa treatment, the outcome of patients does not remain satisfactory due to limitations such as multi-drug resistance and tumor relapse. Therefore, more attention has been drawn to complementary therapies and the use of supplements. In this regard, Polyphenol natural compounds (PNC) and maggot larvae (MaLa) alone or in combination were administered along with chemotherapy (paclitaxel) to N-methyl-N-nitrosourea (MNU)- induced murine tumor model. In addition, in order to identify potential diagnostic or prognostic biomarkers, transcriptomics analysis was performed through a bioinformatics approach. Then transcription profile of ncRNAs with their target hub genes was assessed through qPCR Real-Time, Western blot, and ELISA. According to the bioinformatics results, 17 hub genes (e.g., IL-6, CXCL8, MKI67, IL-2, IL-4, IL-10, IL-1ß, SPP1, LOX, COL1A1, and IFN-γ) were explored that contribute towards inflammation and oxidative stress and ultimately GaCa development. Upstream of the mentioned hub genes, regulatory factors (lncRNA XIST and NEAT1) were also identified and introduced as prognosis and diagnosis biomarkers for GaCa. Our results showed that PNC alone and in combination with MaLa was able to reduce the size and number of tumors, which is related to the reduction of genes expression levels (including IL-6, CXCL8, MKI67, IL-2, IL-4, IL-10, IL-1ß, SPP1, LOX, COL1A1, IFN-γ, NEAT1, and XIST). In conclusion, PNC and MaLa have the potential to be considered as complementary and improving chemotherapy due to their effective compounds. Also, the introduced hub gene and lncRNA in addition to diagnostic and prognostic biomarkers can be used as druggable proteins for novel therapeutic targeting of GaCa.

Management of severely impacted mandibular canines and congenitally missing mandibular premolars with protraction of autotransplanted maxillary premolar.

Transmigrated mandibular canines increase the treatment complexity in terms of both anchorage and biomechanical planning. Additionally, a Class II malocclusion with a deep overbite and associated dental anomalies such as hypodontia can further increase the treatment complexity and the overall treatment time. This case report describes the successful interdisciplinary treatment of a patient, aged 12.5 years, with transmigrated and severely impacted mandibular canines and congenitally missing mandibular second premolars. The transmigrated mandibular right canine was extracted, and a maxillary second premolar was autotransplanted to the missing mandibular right second premolar site with the aid of a stereolithographic donor tooth replica fabricated with 3-dimensional cone-beam computed tomography and a rapid prototyping technique. Furthermore, the autotransplanted tooth was protracted by 4 to 5 mm to close the space caused by the extraction of the mandibular right canine. The impacted mandibular left canine was orthodontically guided into its normal position in the arch. Good esthetic outcome and functional occlusion were achieved.

A micro-computed tomography study of canal configuration of multiple-canalled mesiobuccal root of maxillary first molar.

OBJECTIVES: Detailed information of complex anatomical configuration of mesiobuccal (MB) root is essential for successful endodontic treatment in maxillary first molars. The aims of this study were to investigate the configuration types present in multiple-canalled MB roots of maxillary first molars using micro-computed tomography (µCT) and to evaluate whether further modification to current configuration classifications are needed for in-depth morphology study of MB root canal system. MATERIALS AND METHODS: One hundred and fifty-four extracted human maxillary first molar MB roots were scanned by µCT (Skyscan) and their canals were reconstructed by 3D modeling software. Root canal configurations were categorized according to the classifications proposed by Weine and Vertucci. Canal configurations that did not fit into both classifications were categorized as non-classifiable. RESULTS: One hundred and thirteen (73.4 %) MB roots had multiple canals. The most predominant canal configuration was Weine type III (two orifices and two foramens). Thirty-three (29.2 %) and 20 (17.7 %) MB roots had non-classifiable configuration types that could not be classified by the Weine and Vertucci classification, respectively. Three configurations (types 1-3, 2-3-2-3-2, and 2-3-4-3-2) were first reported in maxillary first molar MB roots. CONCLUSIONS: The present µCT study provided an in-depth analysis of canal configurations of the MB roots of maxillary first molar and suggests that additional modification of current configuration classifications may be needed to more accurately reflect the morphology configurations of MB roots. CLINICAL RELEVANCE: Clinicians should consider the complex canal configurations of the maxillary first molar MB roots during surgical or nonsurgical endodontic procedures.

Effect of heat treatment on cyclic fatigue resistance, thermal behavior and microstructures of K3 NiTi rotary instruments.

OBJECTIVE: The aim of this study was to investigate the effect of heat treatment on the cyclic fatigue resistance, thermal behavior and microstructural changes of K3 NiTi rotary instruments. MATERIALS AND METHODS: Twelve control (as-received) and 12 experimental (heat-treated) K3 NiTi rotary instruments were compared in this study. Those experimental K3 instruments were heated in a furnace for 30 min at 450°C and then quenched in water. The cyclic fatigue resistance was measured with a fatigue tester. The thermal characteristic and the microstructures of both instruments were investigated by differential scanning calorimetry (DSC) and transmission electron microscopy (TEM), respectively. RESULTS: There was a significant increase in the cyclic fatigue resistance between the heat-treated instruments and the as-received instruments (T-test, p < 0.05). DSC showed that the as-received and heat-treated samples were different, with an increased Af (austenite-finish temperature) for the latter. TEM analysis revealed that both as-received and heat-treated instruments were composed mainly of an austenite phase. However, the heat-treated samples had an increased appearance of larger grains, twinning martensite, TiO2 surface layer and a Ni-rich inner layer. CONCLUSIONS: Heat treatment increased the cyclic fatigue resistance of NiTi files and changed the thermal behavior of the instruments without marked changes in the constituting phases of NiTi alloy.

A Cocktail of Polyherbal Bioactive Compounds and Regular Mobility Training as Senolytic Approaches in Age-dependent Alzheimer's: the In Silico Analysis, Lifestyle Intervention in Old Age.

Alzheimer's is a principal concern globally. Machine learning is a valuable tool to determine protective and diagnostic approaches for the elderly. We analyzed microarray datasets of Alzheimer's cases based on artificial intelligence by R statistical software. This study provided a screened pool of ncRNAs and coding RNAs related to Alzheimer's development. We designed hub genes as cut points in networks and predicted potential microRNAs and LncRNA to regulate protein networks in aging and Alzheimer's through in silico algorithms. Notably, we collected effective traditional herbal medicines. A list of bioactive compounds prepared including capsaicin, piperine, crocetin, safranal, saffron oil, coumarin, thujone, rosmarinic acid, sabinene, thymoquinone, ascorbic acid, vitamin E, cyanidin, rhaponticin, isovitexin, coumarin, nobiletin, evodiamine, gingerol, curcumin, quercetin, fisetin, and allicin as an effective fusion that potentially modulates hub proteins and molecular signaling pathways based on pharmacophore model screening and chemoinformatics survey. We identified profiles of 21 mRNAs, 272 microRNAs, and eight LncRNA in Alzheimer's based on prediction algorithms. We suggested a fusion of senolytic herbal ligands as an alternative therapy and preventive formulation in dementia. Also, we provided ncRNAs expression status as novel monitoring strategies in Alzheimer's and new cut-point proteins as novel therapeutic approaches. Synchronizing fusion drugs and lifestyle could reverse Alzheimer's hallmarks to amelioration via an offset of the signaling pathways, leading to increased life quality in the elderly.

Natural remedies medicine derived from flaxseed (secoisolariciresinol diglucoside, lignans, and α-linolenic acid) improve network targeting efficiency of diabetic heart conditions based on computational chemistry techniques and pharmacophore modeling.

Cytokine storms lead to cardiovascular diseases (CVDs). Natural herbal compounds are considered the primary source of active agents with the potential to prevent or treat inflammatory-related pathologies such as CVD and diabetes. Flaxseed contains phytochemicals, including secoisolariciresinol diglucoside (SDG), α-linolenic acid (ALA), and lignans, termed "SAL." Hence, we evaluated the effect of the SAL on the H9c2 cardiac cells in hyperlipidemic and hyperglycemic conditions. Here, candidate hub genes, TNF-α, IL6, SIRT1, NRF1, NPPA, and FGF7, were selected as effective genes in diabetic cardiovascular pathogenesis based on in-silico analysis and chemoinformatic. Myocardial infarction (MI) was induced using H9c2 cardiac cells in hyperlipidemic and hyperglycemic conditions. Real-time qPCR was conducted to assess the expression level of hub genes. This study indicated that SAL compounds bound to the Il-6, SIRT1, and TNF-α active sites as druggable candidate proteins based on the chemoinformatics analysis. This study displayed that the TNF-α, IL6, SIRT1, NRF1, NPPA, and FGF7 network dysfunction in MI models were ameliorated by SAL consumption. Furthermore, SAL compounds improved the function and myogenesis of H9c2 cells in hyperlipidemic and hyperglycemic conditions. Our data suggested that phytochemicals obtained from flaxseed might have proposed potential complementary treatment or preventive strategies for MI. PRACTICAL APPLICATIONS: Phytochemicals obtained from flaxseed (SAL) could reverse diabetic heart dysfunction hallmarks and provide new potential treatment approaches in cardiovascular therapy. SAL could be considered complementary and alternative medicines for treating various disorders/diseases singly or synchronizing with prescription drugs.

Incidence of Altered Sensation after Mandibular Premolar and Molar Periapical Surgery.

INTRODUCTION: Altered sensation is a rare but disturbing adverse event after mandibular premolar and molar periapical surgery procedures, and its incidence is not known. The aim of this study was to determine the incidence of altered sensation after periapical surgery procedures in mandibular premolars and molars. METHODS: This retrospective study includes patients who received periapical surgery in endodontic clinics of a university hospital in the United States. Data were obtained by review of the records for patients who met the inclusion criteria, and statistical analysis of possible predictive factors was performed using the 2-tailed Fisher exact test (α = 0.05). RESULTS: Sixty-two patients (63 teeth, 13 premolars and 50 molars) met the inclusion and exclusion criteria and were analyzed in the study. The first follow-up visit occurred 3 to 37 days after surgery. Altered sensation was observed in 9 patients. Observation of altered sensation was significantly higher (odds ratio = 7.19) after premolar surgeries (5/13) compared with molar surgeries (4/50). CONCLUSIONS: Despite the limited size and retrospective nature of this study, it was concluded that the incidence of altered sensation after periapical surgery appears to be relatively high (14%), with a higher incidence found in premolars compared with molars.

Prognostic Factors of Long-Term Outcomes in Endodontic Microsurgery: A Retrospective Cohort Study over Five Years.

The aim of this study was to analyze the long-term outcomes of endodontic microsurgeries in a cohort and identify their association with prognostic factors. A cohort of endodontic microsurgeries followed up periodically with complete clinical and radiographic records for at least 5 years were reviewed retrospectively. Their survival and healing status and profile characteristics were analyzed by Pearson chi-square test and logistic regression (α = 0.05) to identify prognostic factors that influenced outcomes. Of 652 cases in the cohort, 225 (34.5%) were included. The mean follow-up period was 90.4 months (range, 60-168 months). The long-term success rate was 80.5%, and the 5-year survival rate was 83.5%. Logistic regression showed higher success in anteriors compared to molars (OR = 5.405, (95% CI, 1.663-17.571; p = 0.005)) and in teeth with crown restorations (OR = 10.232, (95% CI, 3.374-31.024; p < 0.001)). Conversely, lower success was found in teeth with periodontal disease (OR = 0.170, (95% CI, 0.032-0.900; p = 0.037)) and maxillary sinus involvement (OR = 0.187, (95% CI, 0.035-0.994; p = 0.049)). Endodontic microsurgery has a highly favorable long-term outcome. Tooth position, crown restoration, periodontal disease, and maxillary sinus involvement were identified as main prognostic factors.

Defining Endodontic Residents' Clinical Experiences: A National Survey.

Endodontic residency programs across the U.S. vary in the exposure they provide to residents in procedures, protocols, and equipment. Having information on the range of clinical experiences provided in programs would be useful for program directors and for applicants who are seeking the best fit for their residency. The aim of this study was to collect information from residents in U.S. endodontic residency programs about the procedures and equipment they experienced in their programs. In January 2018, a 14-question survey was emailed to all 437 endodontic residents with an email address in the 2016-17 American Association of Endodontists Membership Directory. Survey items asked about the number of endodontic procedures, techniques employed, and products used in residents' programs. A total of 133 endodontic residents responded to all or part of the survey, for a 30% response rate. The majority reported completing 151-250 nonsurgical root canals, 26-50 nonsurgical retreatments, 0-10 surgical retreatments, and 0-10 regenerative endodontic procedures during their residencies. All respondents said they used a surgical operating microscope (SOM), and 82% reported using a multi-file rotary system for nonsurgical procedures. Respondents reported that the main instruments they used were Dentsply Sirona file systems, and the most commonly used obturation technique was warm vertical compaction/condensation, reported by 92% of respondents. These endodontic residents reported being exposed to a variety of procedures, products, and protocols during their residency. Based on information they provided, prospective endodontic residency applicants can expect to use the SOM for treatment, to gain extensive experience in primary nonsurgical endodontic treatment, and to not perform endodontic surgery during their first year of postgraduate training.

Root Canal Anatomy and Morphology of Mandibular First Molars in a Selected Iranian Population: An In Vitro Study.

INTRODUCTION: The aim of this study was to evaluate root canal anatomy of mandibular first molars (MFM) in a selected Iranian Population using clearing technique. METHODS AND MATERIALS: A total of 150 extracted MFMs were cleared. The root canal morphology (including the root numbers and root length) and the anatomy of the root canal system (including is the number and type of canals based on Vertucci's classification, canal curvature according to Schneider's method and the presence of isthmus) was evaluated using the buccolingual and mesiodistal parallel x-rays and stereomicroscope. The data were analyzed using the chi-square test. RESULTS: Two and three roots were present in 96.7% and 33% of the teeth, respectively (P=0.0001). All the teeth (100%) had two canals in the mesial root, while 61.3% of the samples had one distal root canal (P=0.006). The root canal configuration in the mesial canal included type IV (55.3%) and type II (41.3%) (P=0.0001). In doubled-canalled distal roots, 68.8% and 24.3% were type II and type IV, respectively (P=0.0001). Isthmii were observed in 44.6% of mesial and 27.3% of distal roots (P=0.0001). CONCLUSION: The notable prevalence of type IV configuration in both roots of mandibular first molars, presence of isthmus and root curvature, necessitates the careful negotiation and cleaning of all accessible canal spaces.

Quantitative analysis of osteoclast-specific gene markers stimulated by lipopolysaccharide.

Lipopolysaccharide (LPS) in the outer layers of Gram-negative bacteria plays an important role in initiating and sustaining periapical lesions. To understand the mechanisms of osteoclastic bone resorption in periapical lesions induced by LPS, we stimulated osteoclast precursors, RAW 264.7 cells with LPS. LPS stimulated osteoclastogenesis when osteoclast precursors were primed with activator for NF-kappaB ligand (RANKL) as little as 24 h. By employing real-time PCR analysis, we have confirmed that osteoclast-like cells stimulated by LPS express high level of osteoclast-specific gene markers such as TRAP, cathepsin K, and calcitonin receptor. These results suggest that bone-resportive action by LPS is partially independent of RANKL.

Comparison of the Osteogenic Potential of Mineral Trioxide Aggregate and Endosequence Root Repair Material in a 3-dimensional Culture System.

INTRODUCTION: The ability to promote osteoblast differentiation is a desirable property of root-end filling materials. Several in vitro studies compare the cytotoxicity and physical properties between mineral trioxide aggregate (MTA) and Endosequence root repair material (ERRM), but not their osteogenic potential. Three-dimensional cultures allow cells to better maintain their physiological morphology and better resemble in vivo cellular response than 2-dimensional cultures. Here we examined the osteogenic potential of MTA and ERRM by using a commercially available 3-dimensional Alvetex scaffold. METHODS: Mandibular osteoblasts were derived from 3-week-old male transgenic reporter mice where mature osteoblasts express green fluorescent protein (GFP) driven by a 2.3-kilobase type I collagen promoter (Col(I)-2.3). Mandibular osteoblasts were grown on Alvetex in direct contact with MTA, ERRM, or no material (negative control) for 14 days. Osteoblast differentiation was evaluated by expression levels of osteogenic genes by using quantitative polymerase chain reaction and by the spatial dynamics of Col(I)-2.3 GFP-positive mature osteoblasts within the Alvetex scaffolds by using 2-photon microscopy. RESULTS: ERRM significantly increased alkaline phosphatase (Alp) and bone sialoprotein (Bsp) expression compared with MTA and negative control groups. Both MTA and ERRM increased osterix (Osx) mRNA significantly compared with the negative control group. The percentage of Col(I)-2.3 GFP-positive cells over total cells within Alvetex was the highest in the ERRM group, followed by MTA and by negative controls. CONCLUSIONS: ERRM promotes osteoblast differentiation better than MTA and controls with no material in a 3-dimensional culture system. Alvetex scaffolds can be used to test endodontic materials.

Chlorhexidine substantivity in root canal dentin.

OBJECTIVE: The purpose of this investigation was to evaluate the substantivity of chlorhexidine (CHX) within a root canal system and to assess how long the CHX remains antimicrobially effective. STUDY DESIGN: Bovine roots were sectioned and standardized to 8 mm. Sections, which served as controls, were treated with 1% sodium hypochlorite and 1 mol/L EDTA, then obturated with gutta percha and AH26 sealer. Experimental sections were treated similarly except they were placed in 2% CHX for 10 minutes prior to obturation. Control specimens were divided into 4 control groups and stored in saline for 1 day, 3 weeks, 6 weeks, and 12 weeks. Experimental specimens were divided into 4 groups and stored in saline for 1 day, 3 weeks, 6 weeks, and 12 weeks. After their respective storage periods, all specimens were halved and canal wall dentin was ground out with Peeso reamers. Dentin specimens were agitated in 700 microl of saline for 5 hours to release CHX. After centrifugation the supernatants were analyzed with UV spectrophotometry at 253 nm. To determine whether the CHX from dentin samples remained antimicrobial, the extracts from experimental and control groups were mixed with cultures of Enterococcus faecalis. RESULTS: After 1 day of storage, the dentin extract contained approximately 0.0048% CHX. After 3, 6 and 12 weeks, dentin extracts contained approximately 0.0023%, 0.0016%, and 0.0010% CHX respectively. Extracts from the storage groups were found to be highly antimicrobial corresponding to the CHX concentration. CONCLUSION: The results of this study indicate that CHX is retained in root canal dentin in antimicrobially effective amounts for up to 12 weeks.

The effect of chlorhexidine as an endodontic disinfectant.

OBJECTIVE: The purpose of this study was to establish whether addition of a 2% chlorhexidine rinse to a conventional treatment protocol enhances the rate of the successful disinfection of the root canal system in vivo. STUDY DESIGN: Twenty-four teeth with infected necrotic pulps and resorbing apical periodontitis were treated with a conventional technique in which 1% NaOCl as irrigant was used. Half of the cases received an additional rinse with 2% chlorhexidine. Prereduced thioglycollate medium was used to take cultures that were incubated for 4 weeks. RESULTS: Cultivable bacteria were retrieved at the conclusion of the first visit in 1 out of 12 chlorhexidine cases whereas in the control group 7 out of 12 cases showed growth. This difference was significant (P < .05). CONCLUSION: The findings are clinically important.

Direct contact between enamel matrix derivative (EMD) and osteoblasts is not required for EMD-induced cell proliferation.

OBJECTIVE: The purpose of this study was to determine whether the effect of enamel matrix derivative (EMD) on osteoblast proliferation is dependent on direct contact between EMD and the cells. STUDY DESIGN: MC3T3-E1 cells were seeded onto 6-well culture plates at an initial density of 5000/cm(2) in Dulbecco's modified eagle medium (DMEM) with 10% fetal bovine serum (FBS). Serum was removed from the culture medium after 24 hours with or without the addition of EMD. Four groups were evaluated: group 1, DMEM only; group 2, DMEM with 100 microg/mL EMD directly added to the culture medium; group 3, DMEM with a culture plate insert (30-mm diameter; 0.4-microm pore size) only; group 4, DMEM with 100 microg/mL EMD added onto a culture plate insert. The porous membrane of the insert prevented direct contact between EMD and the cells. After 3-day incubation, cell morphology was examined and the total cell number per well was counted and analyzed using 1-way ANOVA. RESULTS: EMD formed precipitated aggregates on the membrane of the culture insert with the same appearance as when it was added directly to the medium. The culture plate insert alone did not cause any changes in cell morphology or proliferation. The addition of EMD significantly increased cell number regardless the presence of the culture plate insert. CONCLUSION: This study suggests that direct contact between EMD and osteoblasts is not required to induce cell proliferation. Soluble peptides released from EMD may contribute to the stimulating effects of EMD on cell proliferation.

Emdogain promotes osteoblast proliferation and differentiation and stimulates osteoprotegerin expression.

PURPOSE: The purpose of this study was to investigate the effects of EMD on the growth and differentiation of osteoblastic cells (MC3T3-E1) and on the expression of osteoprotegerin (OPG), a key cytokine that inhibits osteoclastogenesis and osteoclast function. STUDY DESIGN: MC3T3-E1 cells were treated with 100 microg/mL EMD in serum-free medium for 1, 2, 3, 5, and 7 days, or in 2% fetal bovine serum (FBS) for 3 weeks. Cells incubated without EMD served as negative control. At the end of each incubation period, cell numbers were counted and total cellular mRNA was extracted. Northern blot analysis and RT-PCR were performed to determine the mRNA levels of core binding factor alpha (Cbfa1), collagen alpha1 (I), bone sialoprotein (BSP), osteocalcin (OC), insulin-like growth factor I (IGF-I), and OPG. Alkaline phosphatase (ALP) activity was also determined and compared between treatment and control groups. RESULTS: A marked increase in cell numbers was observed in EMD-treated groups from day 2 to day 7 (P < .01). mRNA expression of collagen alpha1 (I), BSP, OC, OPG, and IGF-I were up-regulated in cells treated with EMD. ALP activity was significantly increased by EMD treatment after 3-week culture under differentiating conditions (P < .05). The expression of Cbfa1 was not affected by EMD treatment from day 1 to day 5; the levels were elevated after culturing for 3 weeks in EMD-treated cells. CONCLUSIONS: EMD promotes both proliferation and differentiation of MC3T3-E1 cells and indirectly inhibits osteoclastogenesis and osteoclast function by stimulating the expression of OPG.

Cell and tissue reactions to mineral trioxide aggregate and Portland cement.

OBJECTIVE: Mineral trioxide aggregate (MTA) is being widely used for root-end fillings, pulp capping, perforation repairs, and other endodontic procedures. MTA and Portland cement (PC) have many similar physical, chemical, and biologic properties. PC cement has shown promising potential as an endodontic material in several studies in vitro and in vivo. The purpose of this study was to compare the cytotoxic effect in vitro and the tissue reaction of MTA and Portland cement in bone implantation in the mandibles of guinea pigs. STUDY DESIGN: Millipore culture plate inserts with freshly mixed or set material were placed into the culture plates with already attached L929 cells. After an incubation period of 3 days, the cell morphology and cell counts were studied. Adult male guinea pigs under strict asepsis were anesthetized, during which a submandibular incision was made to expose the symphysis of the mandible. Bilateral bone cavities were prepared and Teflon applicators with freshly mixed materials were inserted into the bone cavities. Each animal received 2 implants, one filled with ProRoot and 1 with PC. The animals were killed after 2 or 12 weeks, and the tissues were processed for histologic evaluation by means of light microscopy. RESULTS: There was no difference in cell reactions in vitro. Bone healing and minimal inflammatory response adjacent to ProRoot and PC implants were observed in both experimental periods, suggesting that both materials are well tolerated. CONCLUSIONS: MTA and PC show comparative biocompatibility when evaluated in vitro and in vivo. The results suggest that PC has the potential to be used as a less expensive root-end filling material.

Effects of root-end filling materials on fibroblasts and macrophages in vitro.

OBJECTIVE: The aim of this study was to investigate the effects of 4 root-end filling materials (mineral trioxide aggregate [MTA], intermediate restorative material [IRM], amalgam, and Retroplast) on cell growth, cell morphology, and cytokine (interleukin [IL]1beta and IL-6) production in mouse fibroblasts and macrophages. STUDY DESIGN: Millipore culture plate inserts with freshly mixed or set root-end filling material were placed into 6-well cell culture plates with already attached mouse fibroblasts or macrophages. Cells cultured with only the Millipore culture plate inserts served as a control. After a 3-day incubation, cell morphology was examined, and the total cell number per well was counted and analyzed by using 1-way analysis of variance. For cytokine assay, mouse macrophages were incubated in 24-well flat-bottom plates with set root-end filling material disks in the bottom. Cells cultured without the material disks served as negative controls, and cells cultured with lipopolysaccharides served as positive controls. After 24-hour incubation, culture media were collected for cytokine assay by using enzyme-linked immunosorbent assay. RESULTS: All root-end filling materials inhibited the cell growth of mouse fibroblasts and macrophages. There was no growth in the originally seeded cells in the fresh IRM, the fresh Retroplast, and the set IRM group. There was no difference between MTA and amalgam for cell growth either in the fresh material groups or in the set material groups. The total cell number in the set Retroplast group was significantly less than that in the set MTA group. Morphologically, MTA was characterized by denatured medium proteins and dead cells adjacent to the material, which were observed only in the fresh MTA group. There was no detected cytokine production in any of the tested material groups. CONCLUSION: All root-end filling materials inhibited cell growth, and none induced IL-1beta and IL-6 production.