634 resultados para Restorative proctocolectomy
Resumo:
OBJECTIVES: To carry out a meta-analysis in order to assess the influencing factors on retention loss and marginal discoloration of cervical restorations made of composites and glass ionomer (derivates). METHODS: The literature was searched for prospective clinical studies on cervical restorations with an observation period of at least 18 months. RESULTS: Fifty clinical studies involving 40 adhesive systems matched the inclusion criteria. On average, 10% of the cervical fillings were lost and 24% exhibited marginal discoloration after 3 years. The variability ranged from 0% to 50% for retention loss and from 0% to 74% for marginal discoloration. Hardly any secondary caries was detected. When linear mixed models with a study and experiment effect were used, the analysis revealed that the adhesive/restorative class had the most significant influence, with 2-step self-etching adhesive systems performing best and 1-step self-etching adhesive systems performing worst; 3-step etch-and-rinse systems, glass ionomers/resin-modified glass ionomers, 2-step etch-and-rinse systems and polyacid-modified resin composites were ranked in between. Restorations placed in teeth whose dentin/enamel had been prepared/roughened showed a statistically significant higher retention rate than those placed in teeth with unprepared dentin (p<0.05). Beveling of the enamel and the type of isolation used (rubberdam/cotton rolls) had no significant influence. SIGNIFICANCE: The clinical performance of cervical restorations is significantly influenced by the type of adhesive system used and/or the adhesive class to which the system belonged and whether the dentin/enamel is prepared or not. 2-Step self-etching- and 3-step etch&rinse systems shall be chosen over 1-step self-etching systems and glass ionomer derivates. The dentin (and enamel) surface shall be roughened before placement of the restoration.
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El estudio analiza la práctica del conferencing en 4 países (Nueva Zelanda, Australia, Irlanda del Norte y Bélgica), y efectúa un estudio empírico que recoge las percepciones de los mediadores sobre si esta práctica restaurativa puede ser una herramienta útil para los programas de mediación en el ámbito penal.
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Des de l’entrada en vigor del nou Codi Penal de 1995, la Direcció General de Mesures Penals Alternatives i Justícia Juvenil ha realitzat un nombre reduït de mediacions. Al novembre de 1998, es va iniciar un programa pilot en alguns jutjats penals i d’instrucció de Catalunya, basat en l’anàlisi de les possibilitats d’aplicació de la reparació a la víctima. També s’estudiaven les primeres experiències de mediació i les tècniques de mediació adquirides pels professionals de la Direcció General en els àmbits de la mediació penal juvenil i la mediació familiar. En aquest estudi, s’avaluen els objectius respecte de l’infractor (responsabilització de les accions i reparació), la víctima (participació en la resolució, sentir-se reparada...), la justícia (promoure la responsabilització, la reparació i la pau social, garantir la resolució...) i la comunitat (apropar la justícia als ciutadans). Els resultats mostren la rellevància que està adquirint la justícia restauradora i la necessitat de facilitar eines perquè es pugui desenvolupar, tot i que de moment el nombre de casos derivats ha estat baix. S’ha demostrat la necessitat de flexibilitat en el tractament dels casos a causa de la diversitat de conflictes. També s’ha vist la necessitat de promoure la formació dels professionals que hi intervenen i d’impulsar reformes legislatives.
Resumo:
Addiction to major drugs of abuse, such as cocaine, has recently been linked to alterations in adult neurogenesis in the hippocampus. The endogenous cannabinoid system modulates this proliferative response as demonstrated by the finding that pharmacological activation/blockade of cannabinoid CB1 and CB2 receptors not only modulates neurogenesis but also modulates cell death in the brain. In the present study, we evaluated whether the endogenous cannabinoid system affects cocaine-induced alterations in cell proliferation. To this end, we examined whether pharmacological blockade of either CB1 (Rimonabant, 3 mg/kg) or CB2 receptors (AM630, 3 mg/kg) would affect cell proliferation [the cells were labeled with 5-bromo-2'-deoxyuridine (BrdU)] in the subventricular zone (SVZ) of the lateral ventricle and the dentate subgranular zone (SGZ). Additionally, we measured cell apoptosis (as monitored by the expression of cleaved caspase-3) and glial activation [by analyzing the expression of glial fibrillary acidic protein (GFAP) and Iba-1] in the striatum and hippocampus during acute and repeated (4 days) cocaine administration (20 mg/kg). The results showed that acute cocaine exposure decreased the number of BrdU-immunoreactive (ir) cells in the SVZ and SGZ. In contrast, repeated cocaine exposure reduced the number of BrdU-ir cells only in the SVZ. Both acute and repeated cocaine exposure increased the number of cleaved caspase-3-, GFAP- and Iba1-ir cells in the hippocampus, and this effect was counteracted by AM630 or Rimonabant, which increased the number of BrdU-, GFAP-, and Iba1-ir cells in the hippocampus. These results indicate that the changes in neurogenic, apoptotic and gliotic processes that were produced by repeated cocaine administration were normalized by pharmacological blockade of CB1 and CB2. The restorative effects of cannabinoid receptor blockade on hippocampal cell proliferation were associated with the prevention of the induction of conditioned locomotion but not with the prevention of cocaine-induced sensitization.
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OBJECTIVE: To determine if the results of resin-dentin microtensile bond strength (µTBS) is correlated with the outcome parameters of clinical studies on non-retentive Class V restorations. METHODS: Resin-dentin µTBS data were obtained from one test center; the in vitro tests were all performed by the same operator. The µTBS testing was performed 8h after bonding and after 6 months of storing the specimens in water. Pre-test failures (PTFs) of specimens were included in the analysis, attributing them a value of 1MPa. Prospective clinical studies on cervical restorations (Class V) with an observation period of at least 18 months were searched in the literature. The clinical outcome variables were retention loss, marginal discoloration and marginal integrity. Furthermore, an index was formulated to be better able to compare the laboratory and clinical results. Estimates of adhesive effects in a linear mixed model were used to summarize the clinical performance of each adhesive between 12 and 36 months. Spearman correlations between these clinical performances and the µTBS values were calculated subsequently. RESULTS: Thirty-six clinical studies with 15 adhesive/restorative systems for which µTBS data were also available were included in the statistical analysis. In general 3-step and 2-step etch-and-rinse systems showed higher bond strength values than the 2-step/3-step self-etching systems, which, however, produced higher values than the 1-step self-etching and the resin modified glass ionomer systems. Prolonged water storage of specimens resulted in a significant decrease of the mean bond strength values in 5 adhesive systems (Wilcoxon, p<0.05). There was a significant correlation between µTBS values both after 8h and 6 months of storage and marginal discoloration (r=0.54 and r=0.67, respectively). However, the same correlation was not found between µTBS values and the retention rate, clinical index or marginal integrity. SIGNIFICANCE: As µTBS data of adhesive systems, especially after water storage for 6 months, showed a good correlation with marginal discoloration in short-term clinical Class V restorations, longitudinal clinical trials should explore whether early marginal staining is predictive for future retention loss in non-carious cervical restorations.
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Aim Background The expected benefit of transvaginal specimen extraction is reduced incision-related morbidity. Objectives A systematic review of transvaginal specimen extraction in colorectal surgery was carried out to assess this expectation. Method Search strategy The following keywords, in various combinations, were searched: NOSE (natural orifices specimen extraction), colorectal, colon surgery, transvaginal, right hemicolectomy, left hemicolectomy, low anterior resection, sigmoidectomy, ileocaecal resection, proctocolectomy, colon cancer, sigmoid diverticulitis and inflammatory bowel diseases. Selection criteria Selection criteria included large bowel resection with transvaginal specimen extraction, laparoscopic approach, human studies and English language. Exclusion criteria were experimental studies and laparotomic approach or local excision. All articles published up to February 2011 were included. Results Twenty-three articles (including a total of 130 patients) fulfilled the search criteria. The primary diagnosis was colorectal cancer in 51% (67) of patients, endometriosis in 46% (60) of patients and other conditions in the remaining patients. A concurrent gynaecological procedure was performed in 17% (22) of patients. One case of conversion to laparotomy was reported. In two patients, transvaginal extraction failed. In left- and right-sided resections, the rate of severe complications was 3.7% and 2%, respectively. Two significant complications, one of pelvic seroma and one of rectovaginal fistula, were likely to have been related to transvaginal extraction. The degree of follow up was specified in only one study. Harvested nodes and negative margins were adequate and reported in 70% of oncological cases. Conclusion Vaginal extraction of a colorectal surgery specimen shows potential benefit, particularly when associated with a gynaecological procedure. Data from prospective randomized trials are needed to support the routine use of this technique.
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Objectives: To study the dental status and treatment needs of institutionalized older adults with chronic mental illness compared to a non-psychiatric control sample. Study Design: The sample size was 100, in which 50 were psychogeriatric patients (study group; SG) classified according to DSM-IV, with a mean age of 69.6 ± 6.7 years, and 50 non-psychiatric patients (control group; CG), with a mean age of 68.3 ± 6.9 years. Clinical oral health examinations were conducted and caries were recorded clinically using the Decayed, Missing and Filled Teeth Index (DMFT). Results were analyzed statistically using the Student"s t-test or analysis of variance. Results: Caries prevalence was 58% and 62% in SG and CG, respectively. DMFT index was 28.3 ± 6.6 in SG and 21.4 ± 6.07 in CG (p < 0.01). Mean number of decayed teeth was higher in SG (3.1) compared to CG (1.8) (p=0.047). Mean number of missing teeth were 25.2 and 16.4 in SG and CG respectively (p<0.05). DMFT scores were higher in SG in all the age groups (p < 0.01). Mean number of teeth per person needing treatment was 3.4 in SG and 1.9 in CG (p= 0.037). The need for restorative dental care was significantly lower in the SG (0.8 teeth per person) than in the CG (1.7 teeth per person) (p = 0.043). Conclusions: Institutionalized psychiatric patients have significantly worse dental status and more dental treatment needs than non-psychiatric patients.
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Des de 1999, el Departament de Justícia aplica el Programa de mediació penal amb infractors adults i víctimes. Aquest Programa, emmarcat en la perspectiva de l’anomenada Justícia Restaurativa, cerca resoldre el conflicte produït pel delicte implicant totes les parts i concedint un paper clau a la víctima, sobre la restitució de la qual gira el procés mediador. La recerca que es presenta fa una avaluació del funcionament d’aquest Programa amb l’objectiu de constatar si la mediació penal pot satisfer algunes de les necessitats de les víctimes de delictes. La valoració que en fan les víctimes que han participat en l’estudi d’avaluació és positiva. Els principals beneficis que destaquen són la reparació material, rebre les disculpes de l’infractor, poder explicar la seva vivència i sentir-se escoltades, i poder participar en la resolució del seu propi procediment i en la resolució final del conflicte.
Resumo:
Desde 1999, el Departamento de Justicia de la Generalitat de Cataluña aplica el Programa de mediación penal con infractores adultos y víctimas. Este Programa, enmarcado en la perspectiva de la llamada Justicia Restaurativa, busca resolver el conflicto producido por el delito implicando a todas las partes y concediendo un papel clave a la víctima, sobre la restitución de la cual gira el proceso mediador. La investigación que se presenta hace una evaluación del funcionamiento de este Programa con el objetivo de constatar si la mediación penal puede satisfacer algunas de las necesidades de las víctimas de delitos. La valoración que hacen las víctimas que han participado en el estudio de evaluación es positiva. Los principales beneficios que destacan son la reparación material, recibir las disculpas del infractor, poder explicar su vivencia y sentirse escuchadas, y poder participar en la resolución de su propio procedimiento y en la resolución final del conflicto.
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Playing a musical instrument demands the engagement of different neural systems. Recent studies about the musician"s brain and musical training highlight that this activity requires the close interaction between motor and somatosensory systems. Moreover, neuroplastic changes have been reported in motor-related areas after short and long-term musical training. Because of its capacity to promote neuroplastic changes, music has been used in the context of stroke neurorehabilitation. The majority of patients suffering from a stroke have motor impairments, preventing them to live independently. Thus, there is an increasing demand for effective restorative interventions for neurological deficits. Music-supported Therapy (MST) has been recently developed to restore motor deficits. We report data of a selected sample of stroke patients who have been enrolled in a MST program (1 month intense music learning). Prior to and after the therapy, patients were evaluated with different behavioral motor tests. Transcranial Magnetic Stimulation (TMS) was applied to evaluate changes in the sensorimotor representations underlying the motor gains observed. Several parameters of excitability of the motor cortex were assessed as well as the cortical somatotopic representation of a muscle in the affected hand. Our results revealed that participants obtained significant motor improvements in the paretic hand and those changes were accompanied by changes in the excitability of the motor cortex. Thus, MST leads to neuroplastic changes in the motor cortex of stroke patients which may explain its efficacy.
Resumo:
Playing a musical instrument demands the engagement of different neural systems. Recent studies about the musician"s brain and musical training highlight that this activity requires the close interaction between motor and somatosensory systems. Moreover, neuroplastic changes have been reported in motor-related areas after short and long-term musical training. Because of its capacity to promote neuroplastic changes, music has been used in the context of stroke neurorehabilitation. The majority of patients suffering from a stroke have motor impairments, preventing them to live independently. Thus, there is an increasing demand for effective restorative interventions for neurological deficits. Music-supported Therapy (MST) has been recently developed to restore motor deficits. We report data of a selected sample of stroke patients who have been enrolled in a MST program (1 month intense music learning). Prior to and after the therapy, patients were evaluated with different behavioral motor tests. Transcranial Magnetic Stimulation (TMS) was applied to evaluate changes in the sensorimotor representations underlying the motor gains observed. Several parameters of excitability of the motor cortex were assessed as well as the cortical somatotopic representation of a muscle in the affected hand. Our results revealed that participants obtained significant motor improvements in the paretic hand and those changes were accompanied by changes in the excitability of the motor cortex. Thus, MST leads to neuroplastic changes in the motor cortex of stroke patients which may explain its efficacy.
Resumo:
Playing a musical instrument demands the engagement of different neural systems. Recent studies about the musician"s brain and musical training highlight that this activity requires the close interaction between motor and somatosensory systems. Moreover, neuroplastic changes have been reported in motor-related areas after short and long-term musical training. Because of its capacity to promote neuroplastic changes, music has been used in the context of stroke neurorehabilitation. The majority of patients suffering from a stroke have motor impairments, preventing them to live independently. Thus, there is an increasing demand for effective restorative interventions for neurological deficits. Music-supported Therapy (MST) has been recently developed to restore motor deficits. We report data of a selected sample of stroke patients who have been enrolled in a MST program (1 month intense music learning). Prior to and after the therapy, patients were evaluated with different behavioral motor tests. Transcranial Magnetic Stimulation (TMS) was applied to evaluate changes in the sensorimotor representations underlying the motor gains observed. Several parameters of excitability of the motor cortex were assessed as well as the cortical somatotopic representation of a muscle in the affected hand. Our results revealed that participants obtained significant motor improvements in the paretic hand and those changes were accompanied by changes in the excitability of the motor cortex. Thus, MST leads to neuroplastic changes in the motor cortex of stroke patients which may explain its efficacy.
Resumo:
Tausta Vaikka nuorisorikollisuus on kriminologisen tutkimuksen perinteinen kohde, on edelleen tarvetta pitkittäistutkimuksille, joissa on laaja, koko väestöä edustava otos. Kriminaalipolitiikan alalla puolestaan rikosten sovittelu ja muut restoratiivisen oikeuden muodot ovat nousseet Suomessakin haastamaan perinteiset rikoskontrollin paradigmat, rangaistuksen ja hoidon. Tutkimuskysymykset Tutkimuksen pääkysymyksenä oli, mitkä lapsuudessa (8 v.) ja nuoruudessa (18 v.) mitatut psykososiaaliset tekijät ovat yhteydessä nuorisorikollisuuden (16-20 v.) määrään ja lajiin. Lisäksi yhtenä kysymyksenä oli, miten varusmiespalvelun aikaiset psykiatriset diagnoosit liittyvät nuorisorikollisuuteen. Lisäksi tutkimme nuorisorikollisuuden esiintyvyyttä ja palvelujen käyttöä, ja vertailimme eri informanttien (tutkimushenkilöt itse, vanhemmat ja opettajat) vastausten ennusvoimaa lasten tulevan rikollisuuden suhteen. Rikosten sovittelun osalta kysymyksenä oli, miten suomalainen sovittelukäytäntö vastaa restoratiivisen oikeuden teoriaa ja miten sovittelua pitäisi kehittää. Aineisto ja metodit Pitkittäistutkimuksemme aineistona oli valtakunnallisesti edustava satunnaisotos, joka vastasi 10% vuonna 1981 Suomessa syntyneistä suomenkielisistä pojista. Ensimmäinen tiedonkeruu tapahtui 1989, kun pojat olivat 8-vuotiaita. Tietoa kerättiin lomakekyselyin pojilta itseltään sekä heidän vanhemmiltaan ja opettajiltaan. Tietoja saatiin 2946 pojasta. Lasten lomakkeena oli Children’s Depression Inventory, vanhemman lomakkeena Rutter A2 ja opettajan lomakkeena Rutter B2. Toinen tiedonkeruu järjestettiin, kun pojat osallistuivat kutsuntoihin 1999. Tietoja saatiin 2330 pojasta. Lomakkeena oli Young Adult Self-Report . Puolustusvoimien rekisteristä saatiin tiedot poikien kutsunnoissa ja palvelusaikana (vuosina 1999-04) saamista psykiatrisista diagnooseista, jotka luokiteltiin kuuteen luokkaan: antisosiaalinen persoonallisuushäiriö, päihdehäiriöt, psykoottiset häiriöt, ahdistuneisuushäiriöt, masennustilat ja sopeutumishäiriöt. Tieto mahdollisesta diagnoosista saatiin 2712 pojasta. Rikollisuus operationalisoitiin poliisin ns. RIKI-rekisteriin vuosina 1998-2001 rekisteröityjen tekojen avulla, kun pojat olivat pääasiassa 16-20-vuotiaita. Rikosten määrän mukaan pojat jaettiin neljään ryhmään: ei rikoksia, 1-2 rikosta (satunnainen rikollisuus), 3-5 rikosta (uusintarikollisuus) ja yli 5 rikosta (aktiivinen uusintarikollisuus). Rikoslajeista muodostettiin viisi kategoriaa: huume-, väkivalta-, omaisuus-, liikenne- ja rattijuopumusrikollisuus. Analyysivaiheessa rekisteridatasta poistettiin liikennerikkomukset. Kaikkiaan tiedot mahdollisista poliisikontakteista saatiin 2866 pojasta. Sovitteludata koostui 16 sovittelujutun havainnoinnista Turussa vuosina 2001- 2003. Tulokset Kaikkiaan 23% pojista oli rekisteröity rikoksesta (poissulkien liikennerikkomukset) nelivuotisen tutkimusperiodin aikana 16-20-vuotiaana. Satunnaisia rikoksentekijöitä oli 15%, uusijoita 4% ja moninkertaisia uusijoita 4%. Rikokset kasautuivat moninkertaisille uusijoille: tämä 4%:n ryhmä teki 72% kaikista rikoksista . Omaisuus- ja liikennerikollisia oli eniten (kumpiakin 11%), ja huumerikollisia vähiten (4%). Kaikki rikoslajit korreloivat keskenään tilastollisesti merkitsevästi. Nuorisorikollisuuden itsenäisiä ennustekijöitä lapsuudessa olivat rikkinäinen perherakenne, vanhempien alhainen koulutustaso, lapsen käytösongelmat ja hyperaktiivisuus. Kun verrattiin eri informantteja (lapset itse ja heidän vanhempansa ja opettajansa), etenkin opettajien vastaukset ennustivat lasten tulevaa rikollisuutta. Nuoruudessa rikollisuuden itsenäisiä korrelaatteja olivat pienellä paikkakunnalla asuminen, vanhempien ero, seurustelu, itse ilmoitettu antisosiaalisuus ja säännöllinen tupakointi ja humalajuominen. Ennus- ja taustatekijöille oli tyypillistä se, että ne olivat lineaarisessa yhteydessä rikosten määrään (ongelmat ja rikosten määrä lisääntyivät käsi kädessä) ja että ne liittyivät useaan rikoslajiin yhtä aikaa. Huumerikollisuudella oli kuitenkin vähemmän itsenäisiä ennus- ja taustatekijöitä kuin muilla rikoslajeilla. Joka kymmenes poika kärsi psykiatrisista häiriöistä. Tämä ryhmä teki noin puolet kaikista rikoksista, ja lähes joka toinen poika, jolla oli psykiatrinen häiriö, oli rekisteröity rikoksista. Rikolliseen käytökseen liittyivät etenkin antisosiaalinen persoonallisuushäiriö ja päihdehäiriöt. Masennustilat olivat kuitenkin ainoa diagnoosiryhmä, joka ei ollut yhteydessä rikollisuuteen. Myös psykiatristen häiriöiden esiintyvyys kasvoi lineaarisesti rikosten määrän kanssa; aktiivisista uusintarikollisista yli puolella (59%) oli psykiatrinen diagnoosi. Rikollisuuden lisäksi erilaiset psykososiaaliset ongelmat kasautuivat pienelle vähemmistölle. Aktiivisten uusijoiden ryhmään olivat tilastollisesti merkitsevästi yhteydessä lähes kaikki ongelmat mitä tutkimme. Kuitenkin tästä ryhmästä vain alle 3% oli käyttänyt mielenterveyspalveluja viimeisen vuoden aikana. Rikossovittelun havainnointitutkimuksen perusteella sovittelussa monet perusasiat ovat kunnossa, ja toiminta on mielekästä niin asianosaisten kuin yhteiskunnankin kannalta. Useimmiten osapuolet kohtasivat ja saivat aikaan sopimuksen, johon he vaikuttivat tyytyväisiltä. Rikoksentekijät olivat motivoituneita korvaamaan aiheuttamansa vahingot. Osapuolet saivat kertoa tarinansa omin sanoin, heitä kuunneltiin ja he ymmärsivät mitä sovittelussa puhutaan ja sovitaan. Sovittelun kuluessa jännitys väheni ja asiat saatiin loppuunkäsiteltyä. Asianosaiset saivat vaikuttaa prosessiin ja sopimukseen, ja uhrin oikeudet olivat sovittelussa keskeisellä sijalla. Restoratiivisen teorian perusteella sovittelussa havaittiin myös kehittämisen varaa: Etenkin nuoria rikoksentekijöitä oli hankala saada osallistumaan tosissaan, ja aikuiset helposti hallitsivat keskustelua. Etukäteistapaamisia ja tukihenkilöitä ei juuri hyödynnetty. Sovitteluja hallitsi puhe sopimuksesta ja rahasta. Työkorvauksia ei käytetty eikä rehabilitaatiota käsitelty. Sekä sovitteluun pääsy että sovittelumenettely riippuivat yksittäisistä henkilöistä. Johtopäätökset Rikosten tekeminen nuoruudessa on melko yleistä ja monimuotoista. Rikokset ja psykososiaaliset ongelmat kasautuvat pienelle ryhmälle ja kulkevat käsi kädessä. Myös psykiatriset häiriöt ovat lineaarisessa yhteydessä rikosten määrään. Rikosriskiä voidaan ennustaa jo lapsuudessa, ja etenkin opettajat ovat tarkkanäköisiä lasten ongelmien suhteen. Eri rikoslajeilla on varsin samanlaisia taustatekijöitä. Aktiiviset rikoksentekijät vastaavat suuresta osasta kokonaisrikollisuutta, tarvitsevat eniten apua, mutta eivät kuitenkaan hakeudu psykososiaalisten palvelujen piiriin. Rikosten sovittelu tarjoaa keinon puuttua ongelmiin varhaisessa vaiheessa ilman leimaamista. Sovittelun kehitystehtävät liittyvät etenkin dialogiin, valmisteluihin, tukihenkilöihin, työkorvauksiin, palveluunohjaukseen ja sovittelun sovellusalaan. Sovittelua ja muita restoratiivisia menettelyjä on kehitettävä ja laajennettava esimerkiksi niin, että niitä voitaisiin käyttää palveluunohjauksen välineenä.
Resumo:
The Repair of segmental defects in load-bearing long bones is a challenging task because of the diversity of the load affecting the area; axial, bending, shearing and torsional forces all come together to test the stability/integrity of the bone. The natural biomechanical requirements for bone restorative materials include strength to withstand heavy loads, and adaptivity to conform into a biological environment without disturbing or damaging it. Fiber-reinforced composite (FRC) materials have shown promise, as metals and ceramics have been too rigid, and polymers alone are lacking in strength which is needed for restoration. The versatility of the fiber-reinforced composites also allows tailoring of the composite to meet the multitude of bone properties in the skeleton. The attachment and incorporation of a bone substitute to bone has been advanced by different surface modification methods. Most often this is achieved by the creation of surface texture, which allows bone growth, onto the substitute, creating a mechanical interlocking. Another method is to alter the chemical properties of the surface to create bonding with the bone – for example with a hydroxyapatite (HA) or a bioactive glass (BG) coating. A novel fiber-reinforced composite implant material with a porous surface was developed for bone substitution purposes in load-bearing applications. The material’s biomechanical properties were tailored with unidirectional fiber reinforcement to match the strength of cortical bone. To advance bone growth onto the material, an optimal surface porosity was created by a dissolution process, and an addition of bioactive glass to the material was explored. The effects of dissolution and orientation of the fiber reinforcement were also evaluated for bone-bonding purposes. The Biological response to the implant material was evaluated in a cell culture study to assure the safety of the materials combined. To test the material’s properties in a clinical setting, an animal model was used. A critical-size bone defect in a rabbit’s tibia was used to test the material in a load-bearing application, with short- and long-term follow-up, and a histological evaluation of the incorporation to the host bone. The biomechanical results of the study showed that the material is durable and the tailoring of the properties can be reproduced reliably. The Biological response - ex vivo - to the created surface structure favours the attachment and growth of bone cells, with the additional benefit of bioactive glass appearing on the surface. No toxic reactions to possible agents leaching from the material could be detected in the cell culture study when compared to a nontoxic control material. The mechanical interlocking was enhanced - as expected - with the porosity, whereas the reinforcing fibers protruding from the surface of the implant gave additional strength when tested in a bone-bonding model. Animal experiments verified that the material is capable of withstanding load-bearing conditions in prolonged use without breaking of the material or creating stress shielding effects to the host bone. A Histological examination verified the enhanced incorporation to host bone with an abundance of bone growth onto and over the material. This was achieved with minimal tissue reactions to a foreign body. An FRC implant with surface porosity displays potential in the field of reconstructive surgery, especially regarding large bone defects with high demands on strength and shape retention in load-bearing areas or flat bones such as facial / cranial bones. The benefits of modifying the strength of the material and adjusting the surface properties with fiber reinforcement and bone-bonding additives to meet the requirements of different bone qualities are still to be fully discovered.
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This study examined high school student perceptions of discretion utilized by educators in high school disciplinary proceedings. Using a sample of 6 high school students who had experienced differing levels of formal discipline, the study investigated the discretionary factors that influence an educator's decision making. The study was a generic qualitative study where the primary source of data collection was open-ended interviews to ensure the integrity of the research as a study of student voices and perceptions. Journaling was also employed to record observations and to identify researcher assumptions. The data were analyzed employing aspects of a grounded theory approach. The findings were coded to reveal 5 areas high school students identified in relation to discipline and discretion: punitive discipline versus problem resolution, effective processes, educator discretion, student discretion, and the student-educator relationship. The final discussion highlights the need for a community vision for high school discipline in order to channel discretion and to uphold students' best interests. Restorative justice is proposed as a feasible vision for high school discipline, whereby participants' responses are measured against a restorative paradigm.