bluuebunny/crossref_metadata_2025 huggingface dataset:
Diet dynamics of the adult piscivorous fish community in Spirit Lake, Iowa, USA 1995–1997
Authors: Liao H. , Pierce C. L. , Larscheid J. G.
Published: March 2003

Abstract – Diets of adults of six important piscivorous fish species, black crappie Pomoxis nigromaculatus, largemouth bass Micropterus salmoides, northern pike Esox lucius, smallmouth bass Micropterus dolomieui, walleye Stizostedion vitreum, and yellow perch Perca flavescens were quantified in Spirit Lake, Iowa, USA from May to October in 1995–1997. Forty‐one prey taxa were found in the diets of these species, including 19 species of fish. The most important prey taxa overall were yellow perch, amphipods and dipterans. Diets of northern pike and walleye were dominated by yellow perch. Largemouth bass diets included large percentages of both yellow perch and black bullhead Ameiurus melas. Smallmouth bass diets included large percentages of both yellow perch and crayfish. Black crappie and yellow perch diets were dominated by invertebrates, primarily amphipods and dipterans. There were pronounced differences in diets among species, among size classes within species and over time. Most of the dominant prey taxa we documented in the diets of piscivorous species were in accordance with previous studies, but a few deviated significantly from expectations. Many of the temporal diet changes were asynchronous among piscivorous species and size classes, suggesting different responses to common prey resources over time.
Long‐term variation in piscivory in a brown trout population: effect of changes in available prey organisms
Authors: L'Abée‐Lund J. H. , Aass P. , Sægrov H.
Published: March 2003

Abstract – The piscivorous behaviour in a brown trout (Salmo trutta L.) population was studied in four discrete periods over seven decades (1917–94) in the hydroelectric reservoir Tunhovdfjord in Norway established in 1919. Piscivorous brown trout were extremely scarce prior to the introduction of two fish species Arctic charr (Salvelinus alpinus L.) and European minnow (Phoxinus phoxinus L.) in the 1920s. Brown trout started eating minnow at 17 cm and Arctic charr at 22 cm of length. In the 1950s, the brown trout predated extensively (60% of analysed trout) on Arctic charr and minnow. During the next four decades, the incidence of piscivorous brown trout declined to 15%, whereas the frequency of brown trout eating Arctic charr remained constant at 10%. The growth pattern, expressed as back‐calculated length, demonstrated similarity in three periods (1920s, 1960s and 1990s) and improved growth in the 1950s. The improvement was addressed the impoundment of a reservoir upstream. We did not find any marked change in growth rate due to piscivority, but coefficient of variance of back‐calculated lengths indicated significant variation in individual growth in age group ≥6 years from 1950 onwards. We accredit this variation to the rise of piscivorous brown trout.
Smallest detectable difference of maximal mouth opening in patients with painfully restricted temporomandibular joint function
Authors: Kropmans Thomas , Dijkstra Pieter , Stegenga Boudewijn , Stewart Roy , De Bont Lambert
Published: March 2003

Changes in maximal mouth opening reflect the impact of temporomandibular disorders and the effect of a therapeutic intervention. No information about the amount of change in maximal mouth opening with regard to reasoned decision‐making is available. The smallest detectable difference, as a measure of reliability assessment, provides this information and is expressed in the unit of the measurement instrument. Twenty‐five consecutive patients (5 males, 20 females) with a painfully restricted temporomandibular joint participated in this study. Measurements of maximal mouth opening were performed by two well‐trained observers on two separate measurement days, one week apart. The maximal mouth opening measurements were repeated three times. Inter‐observer, intra‐observer, and test‐retest reliability varied between 0.90 and 0.96. Inconsistency in measurement results analyzed in terms of absolute error variance, i.e. the measurement facets plus all the interactions, represented 11% of total variance. The smallest detectable difference of maximal mouth opening varied from 9 to 6 mm. For being successful in painfully restricted temporomandibular joint patients, statistically as well as clinically, the clinician has to measure at least 9 mm of improvement in maximal mouth opening. To reduce the smallest detectable difference from 9 to 6 mm, repeated measurement is necessary.
Effects of chlorpromazine on alveolar bone loss in experimental periodontal disease in rats
Authors: De Lima Vilma , Bezerra Mirna Marques , De Menezes Alencar Veruska Bezerra , Daniel Portela Vidal Francisco , Da Rocha Francisco Airton Castro , De Castro Brito Gerly Anne , De Albuquerque Ribeiro Ronaldo
Published: March 2003

Chlorpromazine (CPZ), a phenothiazine derivative, possesses anti‐inflammatory properties, inhibition of tumor neurosis factor‐α(TNF‐α) synthesis and bone resorption. TNF‐α promotes inflammatory changes and bone resorption in periodontitis. We have studied the effect of CPZ in experimental periodontitis. Wistar rats were subjected to a ligature placement around the cervix of the right second upper molars. Alveolar bone loss was evaluated by the sum of the distances between the cusp tip and the alveolar bone along the axis of each molar root, which was subtracted from the contralateral side. Histopathological analysis of the periodontium was based on cell influx, osteoclast number, and alveolar bone and cementum integrity. Animals were weighed daily and total and differential peripheral white blood cell counts were performed 6 h and 1, 7 and 11 d after periodontitis induction. Groups were treated with CPZ 1 h before and daily up to the 11th d of periodontitis. Alveolar bone loss was inhibited 46%, 55.4%, and 76.5% by CPZ at 1, 3 and 9 mg/kg, respectively. Histological analysis showed a significant reduction of cell influx and osteoclast number, as well as preservation of the alveolar process and cementum. CPZ reversed leukocytosis but not weight loss. In conclusion, CPZ reduces bone loss in experimental periodontitis, probably via TNF‐α blockade.
Effects of hypothalamic‐pituitary‐adrenal axis reactivity on periodontal tissue destruction in rats
Authors: Breivik Torbjørn , Opstad Per Kristian , Gjermo Per , Thrane Per S.
Published: March 2003

The aim of this study was to test the hypothesis of an association between hypothalamic‐pituitary‐adrenal (HPA) axis reactivity and progression of periodontal disease. Histocompatible Lewis and Fischer 344 rats respond to stressful stimuli with low and high HPA axis reactivity, respectively. Experimental periodontitis was induced by tying a silk ligature around the neck of maxillary 2nd right molar teeth in 10 Lewis and 10 Fischer 344 rats with contralateral non‐manipulated teeth as controls. Twenty non‐manipulated animals were included. Also, experimental periodontitis was induced in 10 adrenalectomized Wistar rats and in 10 sham‐operated rats. Furthermore, corticosterone pellets were subcutaneously implanted in 9 Lewis rats, while placebo pellets were implanted in 8 animals. Disease progression was evaluated histometrically and radiographically. The low‐responding Lewis rats developed significantly less periodontal breakdown than did the high‐responding Fischer 344 rats. Administration of corticosterone increased the disease development, while adrenalectomy reduced the disease severity. Our findings demonstrate the importance of genetic factors in the development of periodontal disease, and suggest that HPA axis hyper‐activation is one mechanism by which periodontal disease susceptibility may be increased.
Clinical and radiographic judgement of occlusal caries in adolescents
Authors: Poorterman Jan H. G. , Weerheijm Karin L. , Groen Henk J. , Kalsbeek Huib
Published: March 2003

In this study, the clinical and radiographic material of two groups of 17‐ and 20‐yr‐old adolescents, born either in 1970 or in 1976, was compared to study changes in the prevalence of occlusal dentine caries and to determine the additional value of the bitewing radiographs. The first and second molars of 478 participants were included. Clinical data were derived from an epidemiological project. Two examiners judged the bitewing radiographs, of which about 10% was examined by both. The overall Cohen's kappa for interexaminer agreement was 0.87. The prevalence of occlusal caries had not changed for the two age groups; after clinical and radiographic examination, around 33% of the occlusal surfaces of the 17 yr olds and around 25% of the 20 yr olds exhibited dentine caries. The clinical prevalence of occlusal caries in first and second molars was highly underestimated when compared with the radiographs. In the 1976 group, more sealants were recorded during the clinical examination. On the bitewing radiographs, radiolucencies were found underneath one‐half of the sealants of the 17 yr olds and underneath one quarter of the sealants present in the 20 yr olds.
Film‐forming properties and viscosities of saliva substitutes and human whole saliva
Authors: Christersson Cecilia E. , Lindh Liselott , Arnebrant Thomas
Published: March 2003

Hypo‐salivation, related to medical remedies, is an increasing clinical problem. Studies report a weak correlation between subjective mouth dryness and objective sialometry. This indicates that both quantity and quality of saliva are important for the surface‐associated functions of saliva, such as lubrication and hydration, to be expressed. Film‐forming properties and viscosities of three saliva substitutes were compared to human saliva. Adsorption to surfaces was measured by ellipsometry, infrared spectroscopy and drop‐volume technique. Viscosity measurements were carried out using an oscillating rheometer. Saliva, with the lowest viscosity value and the highest protein content, presented superior film retention on both hydrophilic and hydrophobic surfaces. The carboxymethylcellulose‐based MAS 84 showed intermediate values of viscosity, poorest ability to reduce surface tension, and negligible film‐forming capacity. The porcine mucin‐based Saliva Orthana showed about twice the viscosity of saliva and film‐forming capability on preferably hydrophobic substrates. Salinum, a linseed extract, possessed the highest viscosity value and an initial surface tension close to that of saliva. The film retention on hydrophilic surfaces was not as effective as for saliva. The results indicate that the film‐forming capacity of saliva substitutes is a property also to be considered in the exploration of clinically effective artificial salivas.
Effect of fluoride on glucose incorporation and metabolism in biofilm cells of Streptococcus mutans
Authors: Balzar Ekenbäck Susann , Linder Lars E. , Sund Marie‐Louise , Lönnies Helena
Published: March 2003

The aim of this study was two‐fold: firstly, to study the effect of high fluoride concentrations on carbohydrate metabolism in Streptococcus mutans present in biofilms on hydroxyapatite; and, secondly, to evaluate the effect of fluoride‐bound hydroxyapatite on lactic acid formation in growing biofilms of Strep. mutans. Biofilms of a clinical strain of Strep. mutans on saliva‐coated hydroxyapatite beads were incubated with sodium fluoride over a wide range of concentrations. At high fluoride concentrations (>10 mM) the incorporation of [14C]‐labeled glucose decreased by 80–85%, at both pH 7.0 and 5.6. At lower fluoride concentrations, the effect of fluoride on the incorporation of labeled glucose was pH‐dependent in both biofilm cells and in planktonic cells. At pH 7.0, fluoride at concentrations <10 mM had little or no effect. Pretreatment of hydroxyapatite discs with fluoride varnish (Fluor Protector) or fluoride solutions caused a statistically significant reduction of lactic acid formation in associated, growing biofilms of Strep. mutans. Fluoride varnish and 0.2% (47.6 mM) sodium fluoride solution exhibited a statistically significant inhibitory effect on lactate production.
Stimulation of minor salivary glands by intraoral treatment with the cholinesterase inhibitor physostigmine in man
Authors: Hedner Ewa , Birkhed Dowen , Hedner Jan , Ekström Jörgen , Helander Herbert F.
Published: March 2003

A large number of the population, especially the elderly, suffers from dry mouth. The aim of the present investigation was to stimulate the minor salivary glands by the topical application of the cholinesterase inhibitor physostigmine. In eight healthy subjects, 100 µl of the substance, in the concentration interval 2–8 mg/ml, was applied locally to the inside of the lower lip for 1 min. In a separate study comprising 12 dry‐mouth patients, 10 ml of 0.4–1.6 mg/ml physostigmine was administered as a mouth rinse solution for 2 min. Secretion from the labial glands, assessed using the Periotron® method, increased in a dose‐dependent manner in response to physostigmine in both groups. Average peak secretion exceeded baseline by more than 50% throughout the 30‐ to 45‐min observation period; from 1.71 to 2.62 µl cm−2 min−1 among the healthy subjects and from 1.17 to 1.84 µl cm−2 min−1 among the dry mouth patients. No systemic effects were registered as reflected by ECG, heart rate or blood pressure. It is assumed that intraorally applied physostigmine diffuses through the oral mucosa and acts by preserving acetylcholine released from the cholinergic, parasympathetic nerves that innervate the minor salivary glands. The topical application of physostigmine to the oral mucosa may, therefore, be an interesting approach for the treatment of dry mouth.
Longitudinal study of dental caries, tooth mortality and interproximal bone loss in adults with intellectual disability
Authors: Gabre Pia , Martinsson Thore , Gahnberg Lars
Published: March 2003

The investigation focused on longitudinal changes of oral health in a group of adults with intellectual disability. A number of 124 individuals, aged 21–40 yr in 1990, were followed during 8.5 yr. The incidence and prevalence of caries, incidence of tooth mortality, and interproximal bone loss were registered from clinical examinations and bite‐wing radiographs. The subjects visited the dental clinic for preventive dental care on average every third month during the period. The caries incidence was low, on average 0.51 new lesions per yr. Persons with mild intellectual disability experienced more caries than other subjects. During the 8.5 yr, the subjects had lost on average 1.82 teeth, with periodontitis dominating as the reason for tooth mortality. Individuals who cooperated poorly with dental treatment had lost the most teeth. The average annual bone loss in all subjects was 0.03 mm. Subjects with Down syndrome had a higher bone loss compared to those with other diagnoses of intellectual disability. Thus, the major part of the persons with intellectual disability showed satisfactory oral health. However, subjects with poor ability to cooperate with dental treatment and subjects with Down syndrome showed an increased risk for impaired oral health.
Tenascin‐C in developing mouse teeth: expression of splice variants and stimulation by TGFβ and FGF
Authors: Sahlberg Carin , Aukhil Ikramuddin , Thesleff Irma
Published: March 2003

Tenascin‐C is a protein of the extracellular matrix which has been suggested to regulate organogenesis. We have analysed the expression oftenascin‐CmRNA during mouse tooth development. We show that it is transiently expressed during epithelial budding in the condensed dental mesenchyme, and that it reappears later in the dental papilla mesenchyme where it persists in the dental pulp but is downregulated in odontoblasts. Probes corresponding to the domains A4, B, and D of the differentially spliced and domain 7 of the constant region of the FNIII‐like domain show similar patterns of hybridization. Dental epithelium has been shown to induce tenascin‐C in early dental mesenchyme, and we show that growth factors in the transforming growth factor β (TGFβ) and fibroblast growth factor (FGF) families can mimic this effect. FGF‐4, ‐8 and TGFβ‐1 proteins were applied locally by beads on dissected dental mesenchyme, and tenascin‐C expression was analysed after 24 h culture by reverse transcriptase‐polymerase chain reaction (RT‐PCR)in situhybridization, and immunohistochemistry. FGF‐4 and TGFβ‐1 stimulated tenascin‐C expression in E12 dental mesenchymes. RT‐PCR showed induction of several tenascin‐C isoforms by both TGFβ‐1 and FGFs. We conclude that several splice forms are expressed during mouse tooth development, and that TGFβ‐ and FGF‐family growth factors may act as epithelial signals inducing tenascin expression in the dental mesenchyme.
Signal pathways involved in the production of MMP‐1 and MMP‐3 in human gingival fibroblasts
Authors: Domeij Helena , Yucel‐Lindberg Tülay , Modéer Thomas
Published: March 2003

Periodontitis is associated with enhanced production of cytokines, prostaglandins and matrix metalloproteinases (MMPs). The aim of this study was to investigate the production and regulation of MMP‐1 and MMP‐3 in human gingival fibroblasts challenged with the cytokines interleukin‐1β (IL‐1β), tumor necrosis factor α (TNFα) or epidermal growth factor (EGF). The results showed that gingival fibroblasts constitutively produce MMP‐1 and MMP‐3, and that the cytokines IL‐1β, TNFα and EGF increase both MMP‐1 and MMP‐3 production in gingival fibroblasts. The upregulation by the cytokines was apparent at 8 h of incubation and increased thereafter continuously during 48 h of incubation. The upregulation of MMPs, induced by IL‐1β or TNFα, was reduced by the cyxlooxygenase‐2 (COX‐2) inhibitor NS‐398, the p38 MAP‐kinase inhibitor SB 203580, and the tyrosine kinase inhibitor herbimycin A. In addition, MMP‐1 and MMP‐3 production, induced by IL‐1β, TNFα or EGF, was strongly reduced by the presence of the glucocorticoid dexamethasone. Our findings demonstrate that the cytokines IL‐1β, TNFα and EGF, respectively, enhance both MMP‐1 and MMP‐3 production in human gingival fibroblasts, and that the signal pathways COX‐2, MAP‐kinases and tyrosine kinases are partly involved in the production of MMPs.
Relationship between stressful situations, salivary flow rate and oral volatile sulfur‐containing compounds
Authors: Queiroz Celso Silva , Hayacibara Mitsue Fujimaki , Tabchoury Cínthia Pereira Machado , Marcondes Fernanda Klein , Cury Jaime Aparecido
Published: March 2003

The relationship between stress, salivary flow rate and oral volatile sulfur‐containing compounds (VSCs) is not clearly established. Two stressful situations were studied: psychological stress caused by a biochemistry examination (Study I) and psycho‐physiological stress caused by premenstrual syndrome (PMS) (Study II). Seventy‐one undergraduate dental students took part in Study I and VSCs were measured 1 wk before the examination, on the day of examination and 1 wk after. In Study II, 50 women were selected (23 with and 27 without PMS) and the measurements were made during non‐menstrual, premenstrual and menstrual stages. Unstimulated salivary flow was determined in the subjects of both studies. On the day of the biochemistry examination, VSCs significantly increased and salivary flow decreased compared with baseline values. Women with PMS showed higher VSC concentrations during the premenstrual stage than those without PMS (P < 0.05), but the salivary flow was not statistically different. A change in VSCs was observed during different stages of the menstrual cycle for the groups of women, but the salivary flow did not change. The results suggest that a stressful situation can be a predisposing factor for the increase of VSCs in the mouth air, but the mechanism cannot be simply explained by reduction of the salivary flow.
Porcine kallikrein‐4 activation, glycosylation, activity, and expression in prokaryotic and eukaryotic hosts
Authors: Ryu Okhee , Hu Jan C‐C. , Yamakoshi Yasuo , Villemain Jana L. , Cao Xiaohang , Zhang Chuhua , Bartlett John D. , Simmer James P.
Published: March 2003

Kallikrein‐4 (KLK4) is a serine proteinase believed to be important in the normal development of dental enamel. We isolated native KLK4 from developing pig enamel and expressed four recombinant forms. Pig KLK4 was expressed in bacteria with and without the propeptide, and in two eukaryotic systems. Recombinant pig KLK4 was secreted as a zymogen by ‘293’ cells and purified. The proKLK4 was activated in vitro by thermolysin and recombinant pig enamelysin, but not by native KLK4. These results were confirmed using a fluorescent peptide analog of the KLK4 propeptide–enzyme junction. Native KLK4 appears as a doublet at 37 kDa and 34 kDa on sodium dodecyl sulfate–polyacrylamide gel electrophoresis. Removal of N‐linked oligosaccharides by digestion with deglycosidase‐F reduced the doublet to a single band at approximately 28 kDa, demonstrating that the active enzyme is glycosylated, and that the 37 kDa and 34 kDa forms differ only in their number of glycosylations. Deglycosylation was also associated with a loss of proteolytic activity. We digested recombinant pig amelogenin with native KLK4 and characterized the cleavage products by N‐terminal sequencing and mass spectrometry. Eleven cleavage sites in the amelogenin protein were identified, demonstrating that KLK4 degrades amelogenin and is likely to participate in the degradation of enamel proteins in vivo.
High Altitude Residence During Pregnancy Alters Cytokine and Catecholamine Levels
Authors: Coussons‐Read Mary E. , Mazzeo Robert S. , Whitford Margaret H. , Schmitt Mischel , Moore Lorna G. , Zamudio Stacy
Published: March 2003

Coussons‐Read ME, Mazzeo RS, Whitford MH, Schmitt M, Moore LG, Zamudio S. High altitude residence during pregnancy alters cytokine and catecholamine levels. AJRI 2002: 48:344–354 © Blackwell Munksgaard, 2002

This study assessed the impact of high altitude residence during pregnancy on parameters of maternal immune and endocrine system function. Urinary catecholamines, and serum cytokines, estriol, and cortisol were assessed during pregnancy in women living at moderate or high altitude. Women residing at high altitude exhibited elevated levels of proinflammatory cytokines only during pregnancy, and tended to have higher levels of catecholamines during pregnancy than women living at lower altitude. These data suggest that the combination of high altitude and pregnancy alters the maternal neural‐immune axis in a manner that may predispose women to suboptimal birth outcomes.
Spontaneous Secretion of Interleukin‐4, Interleukin‐10 and Interferon‐γ by First Trimester Decidual Mononuclear Cells
Authors: EKERFELT C. , LIDSTRÖM C. , MATTHIESEN L. , BERG G. , SHARMA S. , ERNERUDH J.
Published: March 2003

PROBLEM: A T‐helper cell type 2 (Th2) cytokine dominated microenvironment has been predicted to be crucial for successful pregnancy. However, little information is available about local cytokine secretion in the human decidua. We determined the spontaneous secretion of interleukin‐4 (IL‐4), interferon‐γ (IFN‐γ) and IL‐10 by decidual mononuclear cells at the single cell level and compared it with their secretion by peripheral blood mononuclear cells (PBMC) in the first trimester of pregnancy.

METHODS OF STUDY: The cytokine secretion from decidual and blood cells was detected by a sensitive enzyme‐linked immunosorbent spot‐forming cell (ELISPOT)‐assay.

RESULTS: Cells secreting IL‐4 (median 153, range 8–530), IL‐10 (median 188, range 32–1600) and IFN‐γ (median 123, range 15–1140) were detected in all decidual and blood samples. The cytokine secretion showed a co‐linear pattern in both the blood and decidua, i.e. when one cytokine was secreted at high levels, the others followed the trend. No correlation was found between the number of cytokine secreting cells in blood and decidua for any of the cytokines.

CONCLUSIONS: Interleukin‐4 and IL‐10 are locally secreted in the decidua early during normal pregnancy, probably counteracting the fetal rejecting effects of co‐expressed IFN‐γ. The cytokine secretion by blood cells does not generally reflect the local secretion pattern during first trimester pregnancy.
An analysis of 58 traumatically intruded and surgically extruded permanent teeth
Authors: Ebeleseder K. A. , Santler G. , Glockner K. , Hulla H. , Pertl C. , Quehenberger F.
Published: March 2003

Abstract – Fifty‐eight traumatically intruded and mainly surgically extruded permanent teeth were followed up for 3 years and 4 months (mid‐term results: 29 teeth) and 9 months (short‐term results: 29 teeth) on average. Statistically, the mid‐term results showed more cases of severe crown discoloration (54%) than the short‐term results (9%), but no difference in pulpal and periodontal healing. Three teeth (5%) were lost. Factors which positively influenced pulpal healing were shallow intrusion depth, intact crown and immaturity of the root. Factors which positively influenced periodontal healing were shallow intrusion depth and minimal surgical manipulation. Alveolar bone healing was positively influenced only by shallow intrusion depth.
Comparison of different techniques for obturating experimental internal resorptive cavities
Authors: Goldberg F. , Massone E. J. , Esmoris M. , Alfie D.
Published: March 2003

Abstract – Forty extracted maxillary central incisors were instrumented at the working length to a #50 file. The roots were sectioned transversely with a diamond disk at 7 mm from the anatomical apex. At the opening of the root canal of each section, hemi‐circular cavities were drilled with a specially designed bur. The corresponding root sections were cemented with glue, thus obtaining root canals with similar cavities that simulated internal resorptions. Teeth were embedded in plaster casts to facilitate their handling. The specimens were randomly separated into four groups of 10. The following obturation techniques were evaluated: lateral compaction (group A), hybrid technique (group B), Obtura II (group C), and Thermafil (group D). AH26 was used as the sealer. After obturation, the plaster was removed and the teeth were radiographed in buccolingual and mesiodistal directions to evaluate the quality of the obturation at the IRC. The incisors were then cut with a scalpel at the same level as the previous section, to examine, under a stereomicroscope, the type of material that filled the IRC. Obtura II gave the best results and in most of the specimens obturated with this technique, the IRC were filled mainly with gutta‐percha. Statistical analysis of the data indicated that the differences between group C and the other groups were significant (P<0.05).
Risk evaluation and type of treatment of multiple dental trauma episodes to permanent teeth
Authors: Glendor U. , Koucheki B. , Halling A.
Published: March 2003

Abstract – Studies have shown that some children and adolescents are effected only once with a dental trauma, while others seem to be accident‐prone and suffer from multiple dental trauma episodes (MDTE). Studies have also shown that dental traumas mostly affect upper permanent and medial incisors. Less is known about treatment consequences related to teeth with repeated dental trauma episodes. The aim was therefore to evaluate the risk of MDTE to permanent teeth among children and adolescents by age and gender and to compare types of dental treatment modalities used for patients with one episode and those with MDTE and with single and repeated traumatized teeth. The study was based on a random sample of 83 Danish 6–18‐year‐old children and adolescents born in 1970 who suffered from dental trauma episodes. All patients were followed during a 12‐year period (1976–1988). Forty‐one of the patients were registered with MDTE with a range of 2–7 episodes and a mean of 2.9 episodes/patient (SD=1.1). The mean age at single and MDTE was 11.4 years (SD=3.6) and 8.6 years (SD=2.1), respectively. No significant differences were found between age at first episode and the number of MDTE per patient. The number of patients with MDTE was significantly higher among those who suffered their first trauma episode in the age interval 6–10 years than in the age interval 11–18 years (P<0.001). A survival analysis showed that the risk of sustaining another trauma episode increased by 14.9–30.3% when the first trauma occurred before the age of 11, compared to 0–7.4% after the age of 10. The risk of sustaining multiple injuries was 8.4 times higher when the first trauma episode occurred at 9 years of age, compared with those occurring at age 12. The survival analysis also showed that for every new trauma episode, the interval between them became closer. Forty‐five per cent of the MDTE affected teeth had already sustained an injury. With an increased number of trauma episodes per patient followed an increase in the number of follow‐ups, filling therapy, information and prosthetics, whereas the rates of endodontics, surgery, and consultations were unchanged or even decreased.
Prevalence of teeth with untreated dental trauma among nursery and primary school pupils in Dar es Salaam, Tanzania
Authors: Kahabuka Febronia Kokulengya , Plasschaert Alphons , Van‘t Hof Martin
Published: March 2003

Abstract – The aim of this study was to investigate the prevalence of teeth with untreated dental trauma among children aged 4–15 years in Dar es Salaam, Tanzania. A sample of 4524 children from three districts of different socio‐economic status in the Dar es Salaam area was examined for signs of dental trauma in 1998/99.

In 21% of all children examined, at least one type of untreated dental trauma was observed. A high percentage of untreated dental trauma was observed at the ages of 4 and 15 years. The most frequently observed type of dental trauma was enamel fracture (67%) followed by enamel‐dentin fracture (26%). A significant gender influence on the occurrence of untreated dental trauma was observed, with more boys (23%) having untreated dental trauma than girls (19%). A higher percentage of untreated dental traumas was observed among children in the district with highest SES (26%) compared to the prevalence in the other two districts (14–17%). The findings of this study show that dental traumas are prevalent among Tanzanian children. Therefore, provision of information to the lay community about the importance of early management of dental trauma, ways of preventing trauma and appropriate handling of avulsed teeth is essential in order to minimize the rate of dental injuries and the related complications.
Clinical application of computer‐aided rapid prototyping for tooth transplantation
Authors: Lee Seung‐Jong , Jung Il‐Young , Lee Chan‐Young , Choi Seong Yong , Kum Kee‐Yeon
Published: March 2003

Abstract – The maintenance of healthy periodontal ligament cells in the donor tooth is one of the most important factors for successful tooth transplantation. This is achieved by minimizing the extra‐oral time during the surgical procedure. If a duplicate form of donor tooth could be obtained before extraction, it would be possible to precontour the recipient alveolar bone compatible with the donor tooth, and thereby reduce the extra‐oral time of the donor tooth. We obtained a three‐dimensional image with the real dimensions of the donor tooth from a CT Highspeed AdvantageTM, allowing a life‐sized resin model of the tooth to be fabricated. From 22 clinical cases, we achieved an average total transplantation time of 7.7 min. The average distance between the transplanted root surface and the alveolar bone from 12 available cases was 0.87 mm at the mesial cervix, 0.91 mm at the mesial apex, 0.98 mm at the distal cervix and 1.16 mm at the distal apex on the postoperative radiographs. Clinical data indicate that computer‐aided rapid prototyping may be of value in minimizing the extra‐oral time and possible injury to transplanted tooth during the process of autotransplantation.
Knowledge‐based system for structured examination, diagnosis and therapy in treatment of traumatised teeth
Authors: Robertson A. , Norén J. G.
Published: March 2003

Abstract – Dental trauma in children and adolescents is a common problem, and the prevalence of these injuries has increased in the last 10–20 years. A dental injury should always be considered an emergency and, thus, be treated immediately to relieve pain, facilitate reduction of displaced teeth, reconstruct lost hard tissue, and improve prognosis. Rational therapy depends upon a correct diagnosis, which can be achieved with the aid of various examination techniques. It must be understood that an incomplete examination can lead to inaccurate diagnosis and less successful treatment. Good knowledge of traumatology and models of treatments can also reduce stress and anxiety for both the patient and the dental team. Knowledge‐based Systems (KBS) are a practical implementation of Artificial Intelligence. In complex domains which humans find difficult to understand, KBS can assist in making decisions and can also add knowledge. The aim of this paper is to describe the structure of a knowledge‐based system for structured examination, diagnosis and therapy for traumatised primary and permanent teeth. A commercially available program was used as developmental tool for the programming (XpertRule, Attar, London, UK). The paper presents a model for a computerised decision support system for traumatology.
Tooth replantation after traumatic avulsion: a report of 10 cases
Authors: Kinoshita Shoko , Kojima Rie , Taguchi Yo , Noda Tadashi
Published: March 2003

Abstract  – This report compares the manner in which the avulsed tooth was handled at home versus at school, and presents the different outcomes of the replanted teeth in both groups. Eighteen of 32 avulsed teeth were not replanted, and four replanted teeth could not be followed. Thus, the material comprised 10 avulsed permanent incisors of 10 traumatized children, aged between 8 and 13 years, who were treated at the Pediatric Dental Clinic of Niigata University Dental Hospital. Half of the patients avulsed the tooth at school and the other half at or near home. Of the five teeth avulsed at school, three were kept under wet conditions. The time until their replantation ranged between 0.5 and 3.5 h. Their outcomes were fairly good, except for one incisor that was extracted about 3 years later owing to the undesirable replantation procedures by the dentist. Of the avulsed teeth at or near home, three were left under dry conditions. Their time until replantation ranged scattered between 0.5 and 12 h. Of these, two incisors preserved under wet conditions survived without significant root resorption. These results suggested that information about the way to keep the avulsed tooth was relatively well known to school nurse‐teachers compared with parents. Depending on the kind of lay people, it appears that it is necessary to select the best way to convey information about the management of avulsed permanent teeth.
Repair characteristics of horizontal root fracture: a case report
Authors: Poi Wilson Roberto , Manfrin Thais Mara , Holland Roberto , Sonoda Celso Koogi
Published: March 2003

Abstract  – Radicular fractures in permanent teeth are uncommon injuries among dental traumas, comprising 0.5–7% of the cases. Fracture occurs most often in the middle‐third of the root and rarely at the apical‐third. The present paper reports a clinical case of a horizontal radicular fracture located between the middle‐ and apical‐third of a upper left‐central incisor followed‐up for over 3 years. The tooth was extracted owing to periodontal reasons. Histomorphologically, it showed pulp‐vitality preservation and root healing by hard‐tissue deposition.
The esthetic outcome of autotransplanted premolars replacing maxillary incisors
Authors: Czochrowska Ewa Monika , Stenvik Arild , Zachrisson Björn U.
Published: March 2003

Abstract  – Autotransplantation of developing premolars to replace maxillary incisors has been documented to provide physiologically sound results, but comprehensive studies of the esthetic outcome have not been made previously. In order to assess the applicability of this approach and to identify factors important for planning of treatment, 22 autotransplanted premolars reshaped to incisor morphology were compared to their natural, contralateral maxillary incisors by scoring of features considered important for esthetics (color, soft tissue appearance, tooth morphology, and position). The sum of scores for each feature was used to place the reshaped transplant in one of three categories – Match, Deviate, Mismatch. The 22 patients were asked to fill in a questionnaire which addressed the same features that were examined professionally, and the responses were categorized as either Satisfied, Acceptable, or Dissatisfied. Eleven of the 22 patients had received orthodontic treatment with fixed appliances following the transplantation. Most of the transplanted premolars matched the contralateral incisor, and the majority of patients were satisfied with the appearance of the transplant. Fourteen percentage of the transplants were categorized as Mismatch and 18% of patients reported dissatisfaction. The distribution in categories assessed professionally and by the patients was not significantly different. The color and gingival width of the transplanted tooth were scored as different from the natural incisor in about half of the bilateral comparisons. For those teeth categorized professionally as Mismatch and by patients as Dissatisfied, a potential for esthetic improvement could be identified, as allocation to these categories was primarily due to suboptimal positioning and restorative build‐up of the transplant. Inter‐disciplinary planning is important for successful esthetic results.
Clinical procedures for the immediate reattachment of a tooth fragment
Authors: Rappelli Giorgio , Massaccesi Claudia , Putignano Angelo
Published: March 2003

Abstract  – Uncomplicated crown fractures are frequent dental injuries, especially in young patients. It is beneficial to quickly restore the function and the aesthetics of the traumatized tooth. The immediate fragment reattachment is a therapeutic choice for uncomplicated anterior crown fractures, when the tooth is not luxated and the fragment is correctly stored. The aim of this article is to present the clinical procedures for the immediate fragment reattachment by accurate bonding procedures. The immediate fragment reattachment is a very conservative treatment: it allows the restoration of the original dental anatomy, thus rehabilitating function and aesthetics in a short time, by preserving dental tissues.
Comfort and discomfort of dental trauma splints – a comparison of a new device (TTS) with three commonly used splinting techniques
Authors: Filippi Andreas , Von Arx Thomas , Lussi Adrian
Published: March 2003

Abstract  – The present experimental study compared four dental trauma splints in 10 volunteers. The evaluated splints included a wire‐composite splint (WCS), a button‐bracket splint (BS), a resin splint (RS), and the newly developed titanium trauma splint (TTS). All splints were bonded to the labial surfaces of the maxillary lateral and central incisors and left in place for 1 week. After splint removal, the next splint was placed after a 1‐week rest period. The sequence of splint application was randomized for each individual. The following subjective parameters were assessed using a visual analogue scale: sensitiveness of splinted teeth, irritation of the gingival margin, irritation of the lips, impairment of speech, eating and oral hygiene. The results show that the application of BS leads to a significantly higher irritation of the lips and greater impairment of speech compared to other splints (P < 0.05). The RS leads to an increased and significantly higher irritation of the gingiva (P < 0.05) owing to a significant increase in cleaning difficulties (P < 0.05). In conclusion, WCS and TTS appear to be more accepted splints according to a subjective assessment by 10 volunteers.
Talon cusp causing occlusal trauma and acute apical periodontitis: report of a case
Authors: Segura‐Egea Juan J. , Jiménez‐Rubio Alicia , Velasco‐Ortega Eugenio , Ríos‐Santos José V.
Published: March 2003

Abstract  – The talon cusp, or dens evaginatus of anterior teeth, is a relatively rare dental developmental anomaly characterized by the presence of an accessory cusp‐like structure projecting from the cingulum area or cemento–enamel junction. This occurs in either maxillary or mandibular anterior teeth in both the primary and permanent dentition. One of the main problems caused by accessory cusps are occlusal interferences. The anomalous cusp even can generate occlusal trauma and reversible acute apical periodontitis of the opposing tooth. This article reports a case of talon cusp affecting the permanent maxillary left lateral incisor that caused clinical problems related to occlusal trauma and apical periodontitis caused by a premature contact. The treatment of the occlusal interference produced by the taloned tooth is described.
Local anesthetic failure in endodontics:
Authors: Hargreaves Kenneth M. , Keiser Karl
Published: March 2003

Many patients fear endodontic procedures due to a concern about pain. Although pain treatment is well managed in many endodontic patients, there exists a group of patients who do not receive adequate local anesthesia. This article reviews the mechanisms of local anesthetic failure and focuses on available evidence for developing effective and efficient approaches in local anesthesia.
Behavioural and physiological characterization of inbred mouse strains: prospects for elucidating the molecular mechanisms of mammalian learning and memory
Authors: Nguyen P. V. , Gerlai R.
Published: March 2003

With the advent of recombinant DNA methodology, it has become possible to dissect the molecular mechanisms of complex traits, including brain function and behaviour. The increasing amount of available information on the genomes of mammalian organisms, including our own, has facilitated this research. The present review focuses on a somewhat neglected area of genetics, one that involves the study of inbred mouse strains. It is argued that the use of inbred mice is complementary to transgenic approaches in the analysis of molecular mechanisms of complex traits. Whereas transgenic technology allows one to manipulate a single gene and investigate the in vivo effects of highly specific, artificially induced mutations, the study of inbred mouse strains should shed light on the roles of naturally occurring allelic variants in brain function and behaviour. Systematic characterization of the behavioural, electrophysiological, neurochemical, and neuroanatomical properties of a large number of inbred strains is required to elucidate mechanisms of mammalian brain function and behaviour. In essence, a ‘mouse phenome’ project is needed, entailing the construction of databases to investigate possible causal relationships amongst the phenotypical characteristics. This review focuses on electrophysiological and behavioural characterization of mouse strains. Nevertheless, it is emphasized that the full potential of the analysis of inbred mouse strains may be attained if techniques of numerous disciplines, including gene expression profiling, biochemical analysis, and quantitative trait loci (QTL) mapping, to name but a few, are also included.
Does my mouse have Alzheimer's disease?
Authors: Dodart J.‐C. , Mathis C. , Bales K. R. , Paul S. M.
Published: March 2003

Small animal models that manifest many of the characteristic neuropathological and behavioral features of Alzheimer's disease (AD) have been developed and have proven of great value for studying the pathogenesis of this disorder at the molecular, cellular and behavioral levels. The great progress made in our understanding of the genetic factors that either cause or contribute to the risk of developing AD has prompted many laboratories to create transgenic (tg) mice that overexpress specific genes which cause familial forms of the disease. Several of these tg mice display neuropathological and behavioral features of AD including amyloid β‐peptide (Aβ) and amyloid deposits, neuritic plaques, gliosis, synaptic alterations and signs of neurodegeneration as well as memory impairment. Despite these similarities, important differences in neuropathology and behavior between these tg mouse models and AD have also been observed, and to date no perfect animal model has emerged. Moreover, ascertaining which elements of the neuropathological and behavioral phenotype of these various strains of tg mice are relevant to that observed in AD continues to be a challenge. Here we provide a critical review of the AD‐like neuropathology and behavioral phenotypes of several well‐known and utilized tg mice that express human APP transgenes.
Social behavior and comparative genomics: new genes or new gene regulation?
Authors: Robinson G. E. , Ben‐Shahar Y.
Published: March 2003

Molecular analyses of social behavior are distinguished by the use of an unusually broad array of animal models. This is advantageous for a number of reasons, including the opportunity for comparative genomic analyses that address fundamental issues in the molecular biology of social behavior. One issue relates to the kinds of changes in genome structure and function that occur to give rise to social behavior. This paper considers one aspect of this issue, whether social evolution involves new genes, new gene regulation, or both. This is accomplished by briefly reviewing findings from studies of the fish Haplochromis burtoni, the vole Microtus ochrogaster, and the honey bee Apis mellifera, with a more detailed and prospective consideration of the honey bee.
Acid−base physiology: the ‘traditional’ and the ‘modern’ approaches
Authors: Sirker A. A. , Rhodes A. , Grounds R. M. , Bennett E. D.
Published: March 2003

Summary The interpretation and understanding of acid–base dysfunction has recently been revisited. The ‘traditional’ approach developed from the pioneering work of Henderson and Hasselbalch and is still the most widely used in clinical practice. There are a number of problems identified with this approach, however. The ‘modern’ approach derives from Stewart's work in physical chemistry. In this review we describe the origins of the traditional approach and discusses related concepts. We then describe Stewart's approach, including how it is derived and how it may be used to classify acid–base derangements. The applications of Stewart's approach to clinical scenarios in intensive care is then discussed briefly before we examine some published clinical studies based on his work.
The pharmacodynamics of tinzaparin in healthy volunteers
Authors: Cambus Jean‐Pierre , Saivin Sylvie , Heilmann Jean‐Jacques , Caplain Henri , Boneu Bernard , Houin Georges
Published: March 2003

Summary. We report the pharmacodynamic properties of tinzaparin (175 U/kg antifactor Xa) given as a single daily administration for 5 consecutive days to 14 healthy volunteers as a known safe, effective treatment of deep vein thrombosis and pulmonary embolism. The Cmax for antifactor Xa (0·87 ± 0·15 U/ml) was associated with a 2·4 ± 0·5‐fold prolongation of the activated partial thromboplastin time (APTT) and a high antithrombin activity (0·38 ± 0·1 U/ml). The Cmax value of antifactor Xa was 1·5‐ and twofold lower than those generated by similar doses of nadroparin and enoxaparin respectively. The clearance of antifactor Xa activity (1·29 ± 0·2 l/h) was 1·5‐ and twofold greater than those reported for nadroparin and enoxaparin respectively. These results indicated that the antithrombotic and prohaemorrhagic effects of a low molecular weight heparin were independent from the absolute levels of antifactor Xa activities and from the prolongation of the APTT.