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1.	Farzad, Payam, 1973, et al. (författare) Integration of dental implants in conjunction with edta-conditioned dentin grafts: An experimental study 2021 Ingår i: Dentistry Journal. - : MDPI AG. - 2304-6767. ; 9:6 Tidskriftsartikel (refereegranskat)abstract This study was undertaken to investigate the integration of titanium micro-implants installed in conjunction with previously dentin-grafted areas and to study the morphological appearance, mineral content, and healing pattern of xenogenic EDTA-conditioned dentin blocks and granules grafted to cavities in the tibial bone of rabbits. Demineralized and non-demineralized dentin blocks and granules from human premolars were implanted into cavities prepared on the lateral aspects of the tibias of rabbits. After a healing period of six months, micro-implants were installed at each surgical site. Histological examinations were carried out after 24 weeks. Characterization of the EDTA-conditioned dentin blocks was performed by means of light microscopy, dental X-rays, scanning electron microscopy, and energy dispersive X-ray analysis (EDX). No implants were found to be integrated in direct contact with the dentin particles or blocks. On the EDTA-conditioned dentin surface, the organic marker elements C and N dominated, as revealed by EDX. The hydroxyapatite constituents Ca and P were almost absent on the dentin surface. No statistically significant difference was observed between the EDTA-conditioned and non-demineralized dentin, as revealed by BIC and BA. The bone-inductive capacity of the dentin material seemed limited, although demineralization by means of EDTA indicated higher BIC and BA values in conjunction with the installed implants in the area. A 12 h EDTA treatment did not fully decalcify the grafts, as revealed by X-ray analysis. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
2.	Larsson, Dennis, et al. (författare) Antagonistic effects of 24R,25-dihydroxyvitamin D3 and 25-hydroxyvitamin D3 on L-type Ca2+ channels and Na+/Ca2+ exchange in enterocytes from Atlantic cod (Gadus morhua). 2002 Ingår i: Journal of Molecular Endocrinology. - : Bioscientifica. - 0952-5041 .- 1479-6813. ; 28:1, s. 53-68 Tidskriftsartikel (refereegranskat)abstract There is mounting evidence that vitamin D and its metabolites play important roles in regulating plasma calcium concentrations in teleost fish as in other vertebrates. The aims of the present study were to elucidate the possible cellular target mechanisms for the rapid actions of 24R,25(OH)(2)D(3), 25(OH)D(3) and 1,25(OH)(2)D(3) in Atlantic cod enterocytes at physiological doses, and to establish the concentration and thus the physiological range of circulating 24R,25(OH)(2)D(3), 25(OH)D(3) and 1,25(OH)(2)D(3) in the Atlantic cod. The plasma concentrations of 25(OH)D(3), 1,25(OH)(2)D(3) and 24R,25(OH)(2)D(3) were 15.3 +/- 2.7nM, 125.1 +/- 12.3pM and 10.1 +/- 23.5nM respectively. Exposure of enterocytes to 10mM calcium (Ca(2+)) evoked an increase in intracellular Ca(2+) concentrations ([Ca(2+)](i)). This increase was suppressed by 24R,25(OH)(2)D(3) dose-dependently, with an EC(50) of 4.9nM and a maximal inhibition of 60%. 24R,25(OH)(2)D(3) (20nM) abolished an increase in [Ca(2+)](i) (approximately 252%) in the control enterocytes exposed to 10microM S(-)-BAYK-8644, suggesting that the hormone acts by inhibiting Ca(2+) entry through L-type voltage-gated Ca(2+) channels. Administration of 20nM 24R,25(OH)(2)D(3) to enterocytes in the absence of extracellular Ca(2+) increased [Ca(2+)](i) by approximately 20%, indicating a release of Ca(2+) from intracellular stores. Administration of 25(OH)D(3) (20nM) resulted in a biphasic change in the enterocyte [Ca(2+)](i): within 1--5s, it decreased to 87 +/- 12nM below its mean basal [Ca(2+)](i) (334 +/- 13nM), followed by a rapid recovery of [Ca(2+)](i) to a new level, 10% lower than the initial [Ca(2+)](i). The rapid decrease, the recovery rate and the final [Ca(2+)](i) were all affected dose-dependently by 25(OH)D(3), with EC(50) values of 8.5, 17.0 and 18.9nM respectively. Furthermore, the effects of 25(OH)D(3) were sensitive to sodium (Na(+)), bepridil (10microM) and nifedipine (5 microM), suggesting that 25(OH)D(3) regulates the activity of both basolateral membrane-associated Na(+)/Ca(2+) exchangers and brush border membrane-associated L-type Ca(2+) channels. Administration of 25(OH)D(3) (10nM) to enterocytes in the absence of extracellular Ca(2+) increased [Ca(2+)](i) by approximately 18%, indicating a release of Ca(2+) from intracellular stores. 1,25(OH)(2)D(3) also affected enterocyte [Ca(2+)](i) in a biphasic manner: the rapid decrease, the recovery rate, and the mean final [Ca(2+)](i) were all affected dose-dependently, with EC(50) values of 8.3, 24.5 and 7.7nM respectively. The high EC(50) values for 1,25(OH)(2)D(3) compared with circulating concentrations of 1,25(OH)(2)D(3) (130pM) suggest that this effect is pharmacological, rather than of physiological relevance in enterocyte Ca(2+) homeostasis of the Atlantic cod. It is concluded that 24R,25(OH)(2)D(3) has a physiological role in decreasing intestinal Ca(2+) uptake via inactivation of L-type Ca(2+) channels, whereas the physiological role of 25(OH)D(3) is to increase enterocyte Ca(2+) transport via activation of Na(+)/Ca(2+) exchangers, concurrent with activation of L-type Ca(2+) channels.
3.	Lundquist, Patrik, 1969, et al. (författare) Na+/Ca2+ exchanger isoforms of rat odontoblasts and osteoblasts. 2000 Ingår i: Calcified Tissue International. - 0171-967X. ; 67:1, s. 60-7 Tidskriftsartikel (refereegranskat)abstract In odontoblasts as well as osteoblasts, a number of mechanisms for the inflow and extrusion of Ca2+ have been demonstrated. The entrance of Ca2+ ions into odontoblasts occurs mainly through voltage-gated calcium channels. Extrusion of Ca2+ is found to be an ATP-dependent process and, in addition, Na+/Ca2+-antiports exist, which are provoked by extracellular Na+. The aim of this study was to identify the Na+/Ca2+-antiport isoforms expressed in dentinogenically active rat incisor odontoblasts and to make a comparison with different osteoblastic cells. Using RT-PCR and RNAse protection assay, we demonstrated the expression of three different isoforms, NaCa 3, 7, and 10, of the NCX1-encoded antiport in odontoblasts and osteoblastic cells. When incubated in the presence of Na+, dissected rat incisor odontoblasts as well as the osteoblastic cells extruded Ca2+ ions, as detected by chlorotetracycline and Fura-2 fluorometry, thus supporting a physiological role for the detected isoform expression. Odontoblasts and rat calvarial osteoblasts, as well as osteoblast-like cell lines UMR-106.01 and Saos-2, were shown to exhibit identical phenotypes of Na+/Ca2+-antiport isoform expression, different from the expression patterns of other tissues. The significance of this specific expression pattern is unknown, but there is a possibility that it is in some way related to the unique demands on these cell types to produce mineralized connective tissue.
4.	Örtengren, Ulf, 1959, et al. (författare) Influence of pH and time on organic substance release from a model dental composite: a fluorescence spectrophotometry and gas chromatography/mass spectrometry analysis. 2004 Ingår i: European journal of oral sciences. - : Wiley. - 0909-8836 .- 1600-0722. ; 112:6, s. 530-7 Tidskriftsartikel (refereegranskat)abstract In this study we assessed the influence of pH and time on the degradation and elution of organic substances from the composite resin material, Z-100. To accomplish this, fluorescence spectrophotometry was evaluated as an appropriate technique for the identification of six organic substances (methacrylic acid, methyl methacrylate, hydroquinone, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate and 4,4'-isopropylidenediphenol) that were eluted from resin composite material stored for 24 h or 6 months at pH 4.0, 6.0 or 8.0. In addition, complementary analyses (solid-phase microextraction/gas chromatography/mass spectrometry) were carried out to identify and quantify the substances. The main substances leached from the resin composite were methacrylic acid, triethylene glycol dimethacrylate and hydroquinone. It was concluded that fluorescence spectrophotometry seems to be a suitable, non-destructive technique for the qualitative analysis of eluted organic components. Critical combinations of time and pH allowed the elution of several organic substances, predominantly methacrylic acid, triethylene glycol dimethacrylate and hydroquinone, from the model resin composite, Z-100.
5.	Alamadi, E., et al. (författare) A comparative study of cone beam computed tomography and conventional radiography in diagnosing the extent of root resorptions 2017 Ingår i: Progress in Orthodontics. - : Springer Science and Business Media LLC. - 2196-1042. ; 18, s. 1-8 Tidskriftsartikel (refereegranskat)abstract Root resorptions are assessed and diagnosed using different radiographical techniques. A comparison of the ability to assess resorptions on two-dimensional (2D) and three-dimensional (3D) radiographs is, hitherto, lacking. The aims of this study were to evaluate the accuracy of 2D (periapical radiographs, PA and panoramic radiograph, PAN) and 3D (cone beam computed tomography, CBCT) radiographic techniques in measuring slanted root resorptions compared to the true resorptions, a histological gold standard, in addition to a comparison of all the radiographic techniques to each other. Radiographs (CBCT, PA, and PAN), in addition to histological sections, of extracted deciduous canines from thirty-four patients were analyzed. Linear measurements of the most and least resorbed side of the root, i.e., "slanted" resorptions, were measured using an analyzing software (Facad A (R)). For classification of slanted root resorptions, a modified Malmgren index was used. PAN underestimated the root length on both the least and most resorbed side. Small resorptions, i.e., low modified Malmgren scores, were more difficult to record and were only assessed accurately using CBCT. The root resorption scores were underestimated using PA and PAN. In assessment of linear measures, PAN differed significantly from both CBCT and PA. CBCT is the most accurate technique when measuring and scoring slanted root resorptions.
6.	Almosa, N. A., et al. (författare) Caries risk profiles in orthodontic patients: A 4-year follow-up study using the Cariogram model in governmental vs. private clinics 2018 Ingår i: Saudi Dental Journal. - : Elsevier BV. - 1013-9052. ; 30:2, s. 166-174 Tidskriftsartikel (refereegranskat)abstract Objectives: To (1) analyze caries-related factors and (2) evaluate caries risk using the Cariogram model for governmental and private orthodontic patients at de-bonding and 4 years after de-bonding. Materials and methods: Forty orthodontic patients with mean age of 26.4 years were recruited from a governmental (G) group (n = 20) and private (P) group (n = 20) and were examined at de-bonding (T1) and 4 years after de-bonding (T2). The examination included a questionnaire, plaque scoring, caries examination, bitewing radiographs, and assessment of salivary secretion rate, buffering capacity and cariogenic microorganisms. The data were entered into the Cariogram program to illustrate the caries risk profiles. Results: The chance to avoid new cavities was higher in P-group compared to G-group at T1 (58% and 31%, respectively) (P < 0.01) and T2 (77% and 52%, respectively) (P < 0.001). Plaque index was significantly higher in G-group, and fluoride was used significantly more in P-group at T1 and T2 (P < 0.05). The chance to avoid new cavities was higher at T2 compared to T1 (64% and 44%, respectively) (P < 0.001). Saliva secretion rate and buffer capacity were significantly increased, and the plaque index was significantly decreased at T2 compared to T1 (P < 0.01). Conclusion: According to the Cariogram, orthodontic patients were less likely to avoid new cavities at de-bonding and 4 years after de-bonding in government clinics compared to private clinics, and the caries risk significantly decreased 4 years after orthodontic treatment for all patients, regardless of the location of treatment. (C) 2018 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University.
7.	Almosa, Naif Abdullah, 1981, et al. (författare) Diagnosing the severity of buccal caries lesions in governmental and private orthodontic patients at debonding, using the ICDAS-II and the DIAGNOdent Pen. 2014 Ingår i: The Angle orthodontist. - : The Angle Orthodontist (EH Angle Education & Research Foundation). - 1945-7103 .- 0003-3219. ; 84:3, s. 430-436 Tidskriftsartikel (refereegranskat)abstract Abstract Objectives: To clinically evaluate the prevalence of buccal caries and white spot lesions (WSLs) at debonding in governmental and private orthodontic patients, using the International Caries Detection and Assessment System (ICDAS-II) and the DIAGNOdent Pen, and to study the correlation between the two methods. Materials and Methods: A cross-sectional study was carried out on the nonextracted premolars and anterior teeth of 89 orthodontic patients. They were recruited into two groups based on the treatment center they attended: governmental group (G; n = 45) and private group (P; n = 44). Immediately after debonding, the examination of buccal caries and WSLs on premolars and anterior teeth was carried out using the ICDAS-II and the DIAGNOdent Pen. Cross-tabulation was applied to study the correlation between the ICDAS-II index and the DIAGNOdent Pen by calculating the Spearman correlation coefficient. Results: The G group showed a significantly higher (P < .0001) prevalence of WSLs and/or buccal caries compared to that of the P group based on evaluation by the two methods. Based on ICDAS-II, 43% of the patients in the P group and 9% in the G group were free from any WSLs. In the G group, 22% of the patients had ≥16 lesions, whereas there were none for the P group. The Spearman correlation coefficient between the two methods was .71. Conclusions: The prevalence of caries and/or WSLs at debonding was significantly higher in the G group compared to the P group. The clinical index (ICDAS-II) showed a good correlation with the DIAGNOdent Pen.
8.	Almosa, Naif Abdullah, 1981, et al. (författare) Diagnosing the severity of buccal caries lesions in orthodontic patients at de-bonding using digital photographs. 2014 Ingår i: Acta odontologica Scandinavica. - : Informa UK Limited. - 1502-3850 .- 0001-6357. ; 72:6, s. 474-480 Tidskriftsartikel (refereegranskat)abstract Abstract Objective. The aims of this study were (1) to evaluate the severity of buccal caries lesions according to the International Caries Detection and Assessment System (ICDAS) criteria via scoring buccal caries lesions on digital photographs at the time of de-bonding and (2) to compare this method with clinical examination. Materials and methods. In total, 89 patients treated with upper and lower fixed appliances were clinically examined immediately after de-bonding by the first author and buccal caries were scored according to the ICDAS-II. Close-up digital photographs were taken of 245 teeth with different buccal caries lesion scores according to the ICDAS-II. Thirteen postgraduate orthodontics students independently scored the buccal caries lesions in the digital photographs using the modified clinical criteria (ICDAS-II). Intra- and inter-examiner reliabilities were evaluated by calculating the weighted kappa. To evaluate the validity of diagnosing the severity of buccal caries lesions using digital photographs compared to clinical examination, Spearman's correlation coefficient was calculated. Results. Intra-examiner reliability and the reliability between each examiner and the clinical examination showed moderate-to-excellent agreement, with kappa values of 0.52-0.83. Scoring buccal caries lesions via clinical examinations and scoring via photographs were well correlated according to the modified ICDAS-II criteria (Spearman's correlation coefficient, 0.76). Conclusions. Thus, scoring buccal caries lesions on digital photographs according to ICDAS-II criteria is a reliable and valid method for assessing the severity of buccal caries lesions.
9.	Bäckman, B, et al. (författare) The absence of correlations between a clinical classification and ultrastructural findings in amelogenesis imperfecta. 1993 Ingår i: Acta odontologica Scandinavica. - 0001-6357. ; 51:2, s. 79-89 Tidskriftsartikel (refereegranskat)abstract This study was performed to examine whether a clinical classification of different phenotypes of amelogenesis imperfecta could be discernible at the ultrastructural level. Seventeen primary teeth from 16 children with hypomineralization, hypomaturation, or hypoplastic variants of the disease were collected for histologic studies of the enamel by means of polarized light microscopy, scanning electron microscopy (SEM), and secondary ion mass spectrometry (SIMS). Polarization microscopy showed that the enamel was hypomineralized; in six teeth a wavy configuration of the enamel prisms also appeared. Three histomorphologic main types could be discerned. In 10 of the teeth extensive hypomineralization of the bulk of the enamel was found. One tooth had an unusually thick enamel with only a thin normally mineralized surface layer. SIMS images showed less pronounced signals from Ca2+ and Na+ but with stronger signals from Cl- and CN-, representing the organic component of enamel. The SEM images showed an irregular prism pattern with marked interprismatic areas. Irrespective of the clinical appearance or the hereditary pattern the main findings were hypomineralized enamel with or without wavy bands. Neither of the analytical methods used in this paper distinguishes between the clinical phenotypes of amelogenesis imperfecta.
10.	Granath, Johanna, et al. (författare) Interproximal grinding (disking) of caries in primary molars, attiudes and the extent utilized in a Swedish County 2018 Ingår i: Acta Odontologica Scandinavica. - : Informa UK Limited. - 0001-6357 .- 1502-3850. ; 76:6, s. 394-400 Tidskriftsartikel (refereegranskat)abstract Objective: To assess the occurrence of interproximal grinding as a caries therapy in primary molars, to what degree grinding replaced conventional restorative caries therapy, to what extent anaesthesia was used while grinding and to assess open comments about attitudes about grinding. Materials and methods: A questionnaire was sent to 108 public dental service clinics with questions concerning the use of grinding as a therapy and alternative to restorative treatment, the use of anaesthesia prior to conventional caries therapy and grinding, respectively. In addition, a content analysis of open comments about grinding was performed. Results: Grinding had been performed in 96% of the clinics. Two-thirds of the dentists used grinding as an alternative to conventional restorative treatment at some point. Most dentists used anaesthesia prior to restorative therapy. Prior to grinding, the frequency of anaesthesia was lower (median 5.0) than for conventional restorative therapy (median 8.7) (p < .001). The open comment analysis revealed complex reasons for the use of grinding. Conclusions: Grinding has been widely practiced in parts of Sweden, is presently a technique employed by a multitude of dentists, and that anaesthesia is used less frequently prior to grinding, in comparison to conventional restorative therapy. Dentist considered grinding as a treatment option in specific situations.
11.	Henriksen, J. S., et al. (författare) A pilot study comparing optical coherence tomography, radiography, clinical photography, and polarisation microscopy for studies of hypomineralisation disturbances in enamel 2023 Ingår i: Heliyon. - : Elsevier BV. - 2405-8440. ; 9:2 Tidskriftsartikel (refereegranskat)abstract Aim: To investigate the use of optical coherence tomography (OCT) as a tool to assess general and localised hypomineralisation defects in the enamel. Design and Materials: Ten extracted permanent teeth (four teeth with localised hypomineralisa-tion, four teeth with general hypomineralisation, and two healthy controls) were used in this study. In addition, four participants who underwent OCT served as living controls for the extracted teeth.Methods: The OCT results were compared with clinical photographs, digital radiographs, and polarising microscopy images of tooth sections (considered the gold standard) to determine the method with the most accurate information regarding the extent of enamel disturbances: 1) visibility of enamel disturbance (visible yes/no); if yes, 2) extent of the disturbance in the enamel; and 3) determination of the plausible involvement of the underlying dentin.Results: OCT was more accurate than digital radiography and visual assessment. OCT could provide information about the extent of localised hypomineralised disturbances in the enamel that was comparable to that with polarisation microscopy of the tooth sections.Conclusion: Within the limitations of this pilot study, it can be concluded that OCT is suitable for investigating and evaluating localised hypomineralisation disturbances; however, it is less useful in cases with generalised hypomineralisation of the enamel. In addition, OCT complements radiographic examination of enamel; however, more studies are necessary to elucidate the full extent of the use of OCT in case of hypomineralisation.
12.	Kjellberg, H., et al. (författare) Apical root resorptions in girls with Turner syndrome: a controlled longitudinal study 2022 Ingår i: European Journal of Orthodontics. - : Oxford University Press (OUP). - 0141-5387 .- 1460-2210. Tidskriftsartikel (refereegranskat)abstract Objectives To study, longitudinally, the development of apical root resorptions (ARRs) in Turner syndrome (TS) and to correlate these to the karyotype and orthodontic treatment. Materials and methods Thirty girls with TS participated in the study, mean age 10.8 years (6.6-23.4) at the first registration (T1), and 14.3 years (9.2-25.2) at the second registration (T2). Forty girls without TS, orthodontically untreated, served as controls. ARR was diagnosed in panoramic radiographs, and root/crown ratios of the lower permanent first molar were measured at T1 and T2 with a mean follow-up period of 42 (11-89) months. Results During the follow-up period, ARR was seen in 40% of all TS patients and in 2.5% in the control group. The majority displayed ARR on the distal root of the mandibular first permanent molars (30%). ARR at T2 was seen in 56% of 45,X and isochromosome karyotype and 21% of every other TS karyotype patients. AAR was seen in 5 out of 12 TS patients with orthodontic treatment. No statistically significant differences in root/crown ratios between T1 and T2 were found. Limitations The number of patients studied is limited, thus possible differences might be disguised for this reason. Spatial projection errors in panoramic radiograph recordings might have influenced measurement, resulting in an underestimation of ARR. Conclusions There is a higher risk for ARR in girls with TS and probably the risk is therefore probably also higher during orthodontic treatment. Thus, if treated, frequent radiographic follow-ups should be taken during the treatment. Protocol The protocol was not published before trial commencement.
13.	Lindau, B, et al. (författare) Discrimination of morphological findings in dentine from osteogenesis imperfecta patients using combinations of polarized light microscopy, microradiography and scanning electron microscopy. 1999 Ingår i: International Journal of Paediatric Dentistry. - 0960-7439 .- 1365-263X. ; 9:4, s. 253-61 Tidskriftsartikel (refereegranskat)abstract OBJECTIVES: The aim of this study was to investigate the morphological appearance of dentine in teeth from individuals with osteogenesis imperfecta type I, III and IV using different histological techniques, and to correlate morphological findings to different types of osteogenesis imperfecta. SAMPLE AND METHODS: Extracted or exfoliated primary and permanent teeth were collected from 15 patients with the osteogenesis imperfecta diagnoses I, III or IV, with or without the additional diagnosis dentinogenesis imperfecta. Ground and decalcified sections were prepared from the teeth. Histo-morphological studies of the dentine were performed utilizing light and polarized light microscopy, microradiography and scanning electron microscopy. RESULTS: Characteristic findings were irregular tubules, remnants of capillary inclusions and obliterated pulps. All types of osteogenesis imperfecta exhibited similar types of dentine aberrations, but patients with type III or IV had a higher frequency of aberrations when compared to type I. CONCLUSIONS: The combination of either polarized light microscopy or micro-radiography, together with scanning electron microscopy, gave the most amount of morphological information from dentine samples. In addition, aberrations in dentine structure were more clearly observable. Light microscopy was not critical for the analyses.
14.	Lindau, B M, et al. (författare) Morphology of dental enamel and dentine-enamel junction in osteogenesis imperfecta. 1999 Ingår i: International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children. - 0960-7439. ; 9:1, s. 13-21 Tidskriftsartikel (refereegranskat)abstract OBJECTIVES: The aim of this study was to examine the morphology of primary and permanent human enamel, and the dentine-enamel junction, in individuals with osteogenesis imperfecta (OI) type I, III and IV in undecalcified sections using polarized light microscopy, microradiography and scanning electron microscopy (SEM), and to relate the findings to the type of OI. SAMPLE AND METHODS: Extracted or exfoliated teeth from 15 patients representing the OI types I, III and IV (12 primary teeth from seven patients, and 11 permanent teeth from eight patients). Ten primary and nine permanent teeth from normal healthy patients served as controls. The teeth were serially cut longitudinally in a bucco-lingual direction and contact microradiographs were made. The sections were examined in polarized light. Sections of primary and permanent teeth were examined by means of SEM. RESULTS: This study shows that the permanent enamel from patients with OI exhibits few structural changes. No relationships were found between enamel morphology and the types of OI (I, III, IV). Primary enamel appeared to be slightly more irregularly mineralized, especially in cases with the additional diagnosis dentinogenesis imperfecta. The major findings were deviations in association with the dentine-enamel junction, and locally a lower degree of mineralization. CONCLUSIONS: The mesodermal disease OI might also be manifested in ectodermal enamel, probably because of suboptimal mesenchymal-ectodermal interactions during amelogenesis.
15.	Linde, Anders, 1944, et al. (författare) The role of the odontoblast in calcium transport and mineral formation. 1999 Ingår i: Journal of Hard Tissue Biology. - 1880-828X. ; 8:(spec. issue), s. 221-231 Tidskriftsartikel (refereegranskat)
16.	Lundgren, Ted, 1959, et al. (författare) A secondary ion mass spectroscopic study of the elemental composition pattern in rat incisor dental enamel during different stages of ameloblast differentiation. 1998 Ingår i: Archives of oral biology. - 0003-9969. ; 43:11, s. 841-8 Tidskriftsartikel (refereegranskat)abstract In most earlier studies on the elemental composition pattern of dental enamel, a picture is presented which describes a limited region. In this study, estimates of the incorporation of some critical elements into enamel were correlated with the differentiation stages of the ameloblasts through out the whole tooth. Elemental analyses of rat incisor dental enamel during the secretory, transitional and maturation phases were performed using two different modes of secondary ion mass spectrometry (SIMS). The results were presented as ion images and three-dimensional spatial resolution graphs. In the elemental images of 23Na, 26CN, 35Cl and 39K, counts were detected during the secretory and maturation phases of amelogenesis. Variations were interpreted as resulting from secretion of elements during the secretory phase and resorption during the maturation phase. In line scans the ion yield from enamel during different stages of differentiation of the ameloblasts was analysed. The elements investigated were 12C, 19F, 23Na, 31P, 39K and 77CaCl. As seen in the images, most elements exhibited a higher ion yield during the earlier stages of secretion, and lower yields during the maturation-phase resorption. Cl, together with P, increased during the phases of maturation. In the most apical portions of the teeth, corresponding to a presecretory phase, an inverse pattern was seen for most of the elements. If the surface yield was high at the onset of the secretory phase, the presecretory yields were lower, and vice versa.
17.	Lundgren, Ted, 1959, et al. (författare) How sandblasting on lingual surfaces can be carried out with minimum enamel damage: An in vitro study on human teeth 2020 Ingår i: International Orthodontics. - : Elsevier BV. - 1761-7227. ; 18:4, s. 820-826 Tidskriftsartikel (refereegranskat)abstract Objective > The aim was to assess the extent of enamel damage sandblasting might cause and to identify a combination of sandblasting durations and MicroEtcher nozzle-tooth surface distance (NTD) resulting in the least enamel damage. Materials and methods > Lingual surfaces of 30 human teeth were sandblasted with 2 different distances: 1, 2 mm and 3 different durations: 1, 2, 3s and photographed using a light microscope. The cavity depth and diameter of the sandblasted teeth were measured on the light microscope's pictures. A pilot study was performed to minimize possible combinations of sandblasting durations and distances. To validate the measurement method, sandblasted teeth were ground cut for comparison. Inter-examiner reliability was assessed with Bland-Altman analysis. Mann-Whitney Utest was used to detect cavity and diameter changes for every sandblasting duration and NTD combination. Results > From the pilot study sandblasting durations 1,2 and 3s and NTD < 2 mm were chosen. The cavity diameter of the sandblasted area did not change with increased sandblasting duration nor NTD (P > 0.05). The cavity depth of the sandblasted area increased statistically with an increased sandblasting duration (P < 0.05) but did not increase with an increase NTD (P > 0.05). The 95% limits of inter-examiner agreement were narrow. Conclusion > All distance and duration combinations tested caused enamel damage. Sandblasting duration had greater impact on the cavity depth than the NTD. The blasting duration should, therefore, not exceed 2s and the NTD should be held at maximum 2 mm to minimize the risk of unintentional spread.
18.	Lundgren, Ted, 1959, et al. (författare) Junctional proteins and Ca2+ transport in the rat odontoblast-like cell line MRPC-1. 2001 Ingår i: Calcified tissue international. - 0171-967X. ; 68:3, s. 192-201 Tidskriftsartikel (refereegranskat)abstract A transcellular bulk flow of Ca2+ ions through the odontoblast layer is of central importance during dentinogenesis. For this, specialized mechanisms may exist, which by a concerted action, gate Ca2+ into the proximal end of the cells and extrude the ions towards the mineralization front. To elucidate these mechanisms, an in vitro model would be useful. Mature odontoblasts are, however, post-mitotic cells and cannot be propagated in cell culture. The aim of the present study was, therefore, to characterize the odontoblast-like rat cell line MRPC-1(1) with regard to transcellular Ca2+ transport, barrier function, and intercellular junctions when cultured on membranes in Transwell chambers. The MRPC-1 cells grew as epithelial-like cells in a continuous bilayer separated by a thin collagenous matrix and with intercellular junctional complexes. They exhibited properties of a low-resistance epithelium, maintained a Ca(2+)-dependent diffusion barrier, and exhibited a functional diversity between the two cell layers. MRPC-1 cells expressed ZO-1, occludin, E-, and N-cadherins in addition to alpha-, beta-, gamma- and p120cat catenins, thereby demonstrating some traits in common with, but also differences from, epithelial cells and major differences from fibroblasts. The transcellular Ca2+ flux was inhibitable by nifedipine unidirectionally, giving evidence for an active intracellular Ca2+ transport through voltage-gated channels of the L-type. Similarities with native odontoblasts indicate that MRPC-1 cells may be useful for in vitro studies of transcellular Ca2+ transport mechanisms of importance for the calcification process.
19.	Lundgren, Ted, 1959, et al. (författare) Retrospective study of children with hypophosphatasia with reference to dental changes. 1991 Ingår i: Scandinavian journal of dental research. - 0029-845X. ; 99:5, s. 357-64 Tidskriftsartikel (refereegranskat)abstract In the present retrospective study different dental and medical parameters have been analyzed in 17 Swedish children with established hypophosphatasia (HP). It was demonstrated that the basis for the establishment of the diagnosis varied among different dentists and physicians, and that the diagnostic parameters studied among the children varied. The most reliable parameters for HP included raised levels of phosphoethanolamine in urine, and clinical and radiologic findings associated with the legs. These findings were found among the children more often than lowered values of alkaline phosphatase in serum. Histologic analysis of an extracted tooth made a valuable diagnostic complement. It is concluded that a better diagnostic uniformity is recommended. In a well functioning collaboration with well defined tasks, both dentists and physicians can contribute to a reliable diagnosis.
20.	Lundgren, Ted, 1959, et al. (författare) The use of the stable isotope 44Ca in studies of calcium incorporation into dentin. 1994 Ingår i: Journal of microscopy. - 0022-2720. ; 173:Pt 2, s. 149-54 Tidskriftsartikel (refereegranskat)abstract The incorporation into rat incisor dentin of two calcium isotopes, the stable 44Ca and the radioactive 45Ca, was studied using secondary ion mass spectrometry (SIMS) step-scanning and imaging, and autoradiography, respectively. The results demonstrated a time-dependent incorporation of the calcium isotopes into the mineral phase of dentin. With the SIMS step-scanning, detecting 44Ca, the ion yield was high in the odontoblasts 2 min after intravenous injection. After 10 min a marked increase in signal intensity was found at the dentin mineralization front. This result was consistent with those obtained by 45Ca autoradiography; a peak of incorporation occurred 10 min after injection of the isotope. Likewise, localization of 44Ca to the mineralization front could be demonstrated 10 min after injection by SIMS imaging. In images obtained at earlier intervals, no such increase in ion yield could be detected. The results show that the nonradioactive, stable isotope 44Ca can be used as a marker for biomineralization in a similar way to radioactive 45Ca.
21.	Lundquist, Patrik, 1969, et al. (författare) Phosphate and calcium uptake by rat odontoblast-like MRPC-1 cells concomitant with mineralization. 2002 Ingår i: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research. - 0884-0431. ; 17:10, s. 1801-13 Tidskriftsartikel (refereegranskat)abstract It has been suggested that odontoblasts are instrumental in translocating Ca2+ and inorganic phosphate (Pi) ions during the mineralization of dentin. The aim of this study was to characterize cellular Pi and Ca2+ uptake in the novel rat odontoblast-like cell line mineralizing rat pulpal cell line (MRPC) 1 during mineralization to see if changes in the ion transport activity would occur as the cultures develop and begin forming a mineralized matrix. MRPC-1 cells were cultured in chemically defined medium containing ascorbate and Pi, and cultures were specifically analyzed for cellular P, and Ca2+ uptake activities and expression of type II high-capacity Na+-Pi cotransporters. The odontoblast-like phenotype of the cell line was ascertained by monitoring the expression of collagen type I and dentin phosphopoprotein (DPP). Mineralized nodule formation started at day 9 after confluency and then rapidly increased. Ca2+ uptake by the cells showed a maximum during the end of the proliferative phase (days 5-7). Pi uptake declined to a basal level during proliferation and then was up-regulated simultaneously with the onset of mineralization to a level fourfold of the basal uptake, suggesting an initiating and regulatory role for cellular Pi uptake in mineral formation. This up-regulation coincided with a conspicuously increased glycosylation of NaPi-2a, indicating an activation of this Na+-Pi cotransporter. The study showed that MRPC-1 cells express an odontoblast-like phenotype already at the onset of culture, but that to mineralize the collagenous extracellular matrix (ECM) that formed, a further differentiation involving their ion transporters is necessary.
22.	Nilsson, T, et al. (författare) A computerized induction analysis of possible co-variations among different elements in human tooth enamel. 1996 Ingår i: Artificial intelligence in medicine. - 0933-3657. ; 8:6, s. 515-26 Tidskriftsartikel (refereegranskat)abstract In recent decades software tools in the area of artificial intelligence have rapidly developed for use in personal computers. Interactive rule induction utilizing mathematical algorithms has become a powerful tool in data analysis and in making rules and patterns explicit. Data from a Secondary Ion Mass Spectrometry (SIMS) elemental analysis of human dental enamel were used to elucidate co-variations between certain elements. A co-variation analysis was performed employing a computerized induction analysis program, as well as a neural network program. Both analyses, confirming each other, revealed co-variations between certain elements in dental enamel in addition to exclusion of data of no importance for chosen outcomes. The results are presented in hierarchic diagrams, in which the importance for every specific element is given by its position and level in the diagram (decision tree). From the results it became evident that elements such as chlorine and sodium expressed a high co-variation level. Similarly fluorine and potassium co-varied, as well as magnesium and the trace element strontium. It was demonstrated that data from an elemental analysis could be processed by an induction analysis to reveal co-variations between certain elements in tooth enamel. The biological significance of these data is not fully understood, and further analyses in the field are needed.
23.	Nilsson, T, et al. (författare) Differences in co-variation of inorganic elements in the bulk and surface of human deciduous enamel: an induction analysis study. 1998 Ingår i: Connective tissue research. - 0300-8207. ; 38:1-4 Tidskriftsartikel (refereegranskat)abstract This paper demonstrates a method for determination of co-variation between some inorganic elements in the bulk and surface areas of human tooth enamel. The technique is based on a computerised induction analysis of data obtained by secondary ion mass spectrometry (SIMS). When comparing the present data with an earlier study from our laboratory, it became evident that with only a moderate increase in the amount of data for the induction analysis, the results increased very considerably in reliability and precision. The patterns of co-variation between different elements differed between the bulk- and surface enamel. Only Mg expressed a similar pattern. In the bulk enamel the elements Na and P expressed a high degree of co-variation. Similarly, Mg and C expressed a high degree of co-variation. Mg was an element often found to co-vary with bulk enamel elements. In the enamel surface, F and Cl co-varied. In addition, Cl was an element often found to co-vary with other enamel surface elements.
24.	Rexhaj, Flaureta, 1994, et al. (författare) Evaluation of method parameters for sound undecalcified dental enamel proteomics using liquid chromatography-mass spectrometry 2023 Ingår i: Archives of Oral Biology. - 0003-9969. ; 155 Tidskriftsartikel (refereegranskat)abstract Objective: This study aims to validate a methodology for analyzing undecalcified, sound dental enamel proteomics using Liquid Chromatography-Mass Spectrometry (LC-MS). The study evaluates various parameters, including the impact of dental root coverage on protein contamination, the efficacy of protease inhibitors during enamel sample preparation, repeatability of LC-MS measurements on dental enamel, and statistical analysis. The study also assesses the effectiveness of combined trypsin and semi-trypsin searches in Mascot for obtaining additional protein identification data. Design: Sound dental enamel was removed using a wet grinding technique, then digested with trypsin and labeled with TMT prior to LC-MS analysis. The resulting proteomes were matched against the Homo sapiens Swissprot Database, with searches in Mascot performed using both trypsin and semitrypsin. Statistical methods were employed to analyze the data. Results: The study found that covering dental roots with composite during dental enamel microdissection is advisable, while using protease inhibition during microdissection may not be fully supported. The proteomic analyses demonstrated statistical repeatability and reliability, with consistent and reproducible proteomic data obtained from healthy dental enamel. Furthermore, employing both trypsin and semitrypsin searches in Mascot provided additional proteomic information. Conclusions: Overall, this study validates a methodology for analyzing undecalcified, sound dental enamel proteomics using LC-MS, and provides insights into various factors that can affect the quality and reliability of proteomic data. These findings have implications for future studies pursuant to understanding the proteomic mechanisms underlying dental enamel formation and other associated processes.
25.	Rexhaj, Flaureta, 1994, et al. (författare) Proteomic profiling of human dental enamel affected by molar incisor hypomineralisation of different clinical severity grades: an in vitro study 2024 Ingår i: EUROPEAN ARCHIVES OF PAEDIATRIC DENTISTRY. - 1818-6300 .- 1996-9805. Tidskriftsartikel (refereegranskat)abstract Purpose The aim of this study was to explore the potential to profile and distinguish varying clinical severity grades of MIH, compared to normal enamel, using proteomics.Methods Liquid chromatography-mass spectrometry analyses were conducted on enamel samples of extracted teeth, from 11 children and adolescents, spanning an age range of 6-18 years. Enamel powder samples were collected from extracted, third molars (n = 3) and first permanent molars diagnosed with MIH (n = 8). The MIH tooth samples were categorized into subgroups based on clinical severity grade. The data were statistically analyzed using ANOVA and Welch's t test.Results Teeth affected by MIH exhibited a diverse array of proteins, each with different functions related to dental enamel, distinguishing them from their normal enamel counterparts. The application of microdissection combined with LC-MS techniques has revealed the potential to discern unique proteomic profiles among MIH-affected teeth, characterized by varying clinical severity grades. Both analyzed MIH groups displayed consistent trends in the presentation of biological processes, including underabundance of proteins primarily associated with cell organization and biogenesis. Furthermore, proteins linked to cell death were overabundant in both MIH groups.Conclusion Proteomics enabled the detection and differentiation of various proteins across different clinical severity grades of MIH.
26.	Rizell, Sara, 1963, et al. (författare) Altered inorganic composition of dental enamel and dentin in primary teeth from girls with Turner syndrome. 2010 Ingår i: European journal of oral sciences. - : Wiley. - 1600-0722 .- 0909-8836. ; 118:2, s. 183-90 Tidskriftsartikel (refereegranskat)abstract In Turner syndrome (TS) one X-chromosome is missing or defective. The amelogenin gene, located on the X-chromosome, plays a key role during the formation of dental enamel. The aim of this study was to find support for the hypothesis that impaired expression of the X-chromosome influences mineral incorporation during amelogenesis and, indirectly, during dentinogenesis. Primary tooth enamel and dentin from girls with TS were analysed and compared with the enamel and dentin of primary teeth from healthy girls. Qualitative and quantitative changes in the composition of TS enamel were found, in addition to morphological differences. Higher frequencies of subsurface lesions and rod-free zones were seen in TS enamel using polarized light microscopy. Similarly, scanning electron microscopy showed that the enamel rods from TS teeth were of atypical sizes and directions. Using X-ray microanalysis, high levels of calcium and phosphorus, and low levels of carbon, were found in both TS enamel and dentin. Using microradiography, a lower degree of mineralization was found in TS enamel. Rule induction analysis was performed to identify characteristic element patterns for TS. Low values of carbon were the most critical attributes for the outcome TS. The conclusion was that impaired expression of the X-chromosome has an impact on dental hard tissue formation.
27.	Robertson, Agneta, 1954, et al. (författare) Pulp calcifications in traumatized primary incisors. A morphological and inductive analysis study. 1997 Ingår i: European journal of oral sciences. - 0909-8836. ; 105:3, s. 196-206 Tidskriftsartikel (refereegranskat)abstract The purpose of this study was to investigate histopathological changes in primary teeth following trauma, and to look for possible correlations between the morphology of pulpal calcification and clinical findings. The material consisted of 123 primary teeth from 98 Danish children aged 9-108 months (mean age 33.5 +/- 19.7 months) at the time of injury. The specimens were analyzed by means of light and scanning and transmission electron microscopy. Data from the clinical investigation and from predetermined ranked parameters from the histological analysis were processed in a computerized inductive analysis program. The results, describing patterns of co-variation, are presented as a decision tree. The most common diagnosis was intrusion luxation (54%). In 41% of all teeth, the degree of obliteration was less than 1/4 of the pulpal lumen. In most cases (79%), no denticles were visible. When present, 80% of the denticles had a bone-like appearance. Tissues occluding the pulpal lumen were either dentin-like (49%), bone-like (19%), or fibrotic (9%). It could be concluded that these varying responses could not be correlated with explicit clinical diagnoses. However, in certain combinations, histological parameters could be correlated to clinical findings.
28.	Sabel, Nina, 1973, et al. (författare) Elemental composition of normal primary tooth enamel analyzed with XRMA and SIMS. 2009 Ingår i: Swedish dental journal. - 0347-9994. ; 33:2, s. 75-83 Tidskriftsartikel (refereegranskat)abstract There is an interest to analyze the chemical composition of enamel in teeth from patients with different developmental disorders or syndromes and evaluate possible differences compared to normal composition. For this purpose, it is essential to have reference material. The aim of this study was to, by means of X-ray micro analyses (XRMA) and secondary ion mass spectrometry (SIMS), present concentration gradients for C, O, P and Ca and F, Na, Mg, Cl, K and Sr in normal enamel of primary teeth from healthy individuals. 36 exfoliated primary teeth from 36 healthy children were collected, sectioned, and analyzed in the enamel and dentin with X-ray micro analyses for the content of C, O, P and Ca and F, Na MgCl, K and Sr. This study has supplied reference data for C, O, P and Ca in enamel in primary teeth from healthy subjects. No statistically significant differences in the elemental composition were found between incisors and molars.The ratio Ca/P is in concordance with other studies. Some elements have shown statistically significant differences between different levels of measurement. These results may be used as reference values for research on the chemical composition of enamel and dentin in primary teeth from patients with different conditions and/or syndromes.
29.	Sandström, Monica, et al. (författare) Tandläkarutbildningen får gott betyg 2011 Ingår i: Tandläkartidningen. - 0039-6982. ; 103:6, s. 64-69 Tidskriftsartikel (refereegranskat)abstract In 2004, 2005 and 2006 Statistiska Central- byrån (Statistics Sweden), on commission of the Swedish Dental Association, carried out an opinion study among newly graduated dentists in Sweden in order to evaluate dental skill after completed dental training. These studies were performed at the dental institutions in Sweden and were published in Tandläkartidningen 2007. The aim of this study was to, once again, evaluate these opinions. This study is a follow up of the previous studies, and emphasize on the impor- tance of how opinion studies are performed. In contrast to the former studies this study had a qualitative approach. Instead of questions with predefined answers, telephone interviews with open answers were performed. The possibility that the questionnaire design could influence the result outcome is discussed. 88 percent of the re- sponders in the present study were satisfied with their clinical training, compared to 70 percent in the earlier study. Thirty percent of the respond- ers stated the clinical training to be insufficient, though, in particular in prosthetics and oral sur- gery. More than 50 percent stated insufficient training in dental care for disabled and elderly patients. Most of the responders answered that their preclinical training were sufficient and adequate. In contrast to previous studies no, or small, differences in opinion about the training at different dental institutions were reported. Most of the newly graduated dentists had a tutor dur- ing their first employments.
30.	Werthén, Maria, 1957, et al. (författare) Intracellular Ca(2+) mobilization and kinase activity during acylated homoserine lactone-dependent quorum sensing in Serratia liquefaciens. 2001 Ingår i: The Journal of biological chemistry. - 0021-9258. ; 276:9, s. 6468-72 Tidskriftsartikel (refereegranskat)abstract Quorum sensing in Gram-negative bacteria involves acylated homoserine lactones (AHLs) and a transcription factor, activated by the AHLs. In this study, a possible involvement of intracellular Ca(2+) as second messenger and/or protein kinase activity during signal transduction is analyzed. When N-hexanoyl-l-homoserine lactone was added to a suspension of Fura-2-loaded Serratia liquefaciens, there was a decline in [Ca(2+)](i), measured as a decrease in the Fura-2 fluorescence ratio. As controls, the addition of the signal molecule N-3-oxohexanoyl-l-homoserine lactone, which is not produced by S. liquefaciens, did not induce changes in [Ca(2+)](i). Using a protein kinase activity assay on AHL-stimulated cells, an increase in kinase activity after N-butanoyl-l-homoserine lactone stimulation of S. liquefaciens cells was detected, whereas the kinase activity induced by N-3-oxohexanoyl-l-homoserine lactone was not statistically significant. The conclusion from this study is that changes in [Ca(2+)](i) are involved in quorum sensing signal transduction in the Gram-negative bacteria S. liquefaciens. We also conclude that kinase activity is induced in S. liquefaciens upon AHL stimulation. We suggest that the transient intracellular [Ca(2+)] changes and kinase activity, activated by the AHL signal, are critical for the quorum-sensing signal transduction.

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