Vid TCF-blekning av pappersmassa är väteperoxid en av huvudkemikalierna. I dagsläget är det svårt att styra blekstegen. Operatörerna måste ta hänsyn till produktionstakt, blekbarheten på massan varierar och fördröjning i trender. PO-bleksteget på Södra Cell Värö har en ungefärlig uppehållstid på 4 timmar och det är först efter så lång tid som man kan se hur en förändring verkligen slår igenom. Överblekning kostar väldigt mycket i kemikalieåtgång och det är därför efterfrågat ett sätt att kunna styra och optimera peroxidblekningssteget. Ett delsteg för detta var att simulera steget experimentellt och från dessa data ta fram en matematisk modell som förutsäger ljusheten. Massa togs ut från fabriken och blektes på labb under kontrollerade förhållanden med satsningar liknande verkliga i fabriken. De parametrar som studerades på labb var temperatur, väteperoxidsats och alkalisats då de påverkar ljusheten mest. En modell för ljushetsökning anpassades sedan till framtagna blekdata. Ekvationer för förbrukning av väteperoxid och hydroxidjoner togs också fram från analyser på blekfiltraten. Med ingående parametrar som startkoncentrationer av kemikalier, temperatur och massakoncentration förutsäger modellen ljusheten väl vid verifiering jämfört med fabrik och verifieringsblekning på labb. Modellen ligger något högre jämfört med fabrik men det var förväntat då förhållanden på labb ger ett renare system. För de parametrar som studerats anpassade sig modellen bra till förändringar och vid verifiering på labb syntes att modellen även svarade med en korrekt ljushet vid förändring i massakoncentration och ingående ljushet i steget. / During TCF-bleaching of pulp, hydrogen peroxide is one of the main chemicals. Today it is difficult to control the bleaching stages. The process operators must consider the production rate, changes in the bleach ability of the pulp and delays of trends in the control system. The PO-bleaching stage at Södra Cell Värö has approximately a retention time of four(4) hours and it is first after that, a result of a change in the process can be seen. Overbleaching is expensive due to high chemical need and therefore it is requested to find a way to control and optimize the peroxide bleaching stage. One way to do this was too simulate the stage experimentally and from those kinetic data accomplish a mathematical model that predicts the brightness increase of the pulp. Pulp from the mill was bleached at the laboratory under controlled conditions and with charges similar to what are used in the plant. The parameters that were studied at lab were temperature, hydrogen peroxide charge and alkali charge as they affect the brightness mostly. A model for brightness increase was adjusted to the achieved bleaching data. Equations for consumption of hydrogen peroxide and hydroxide anions were also developed from analyses of the bleaching filtrates.  From the start parameters, as concentration of the chemicals, temperature and pulp concentration, the model predicts the brightness well according to verification of data from mill and verification bleaching at laboratory. The value from the model is somewhat higher compared to that of the plant but that was expected due to the fact that the conditions at lab give a cleaner system. For those parameters that were studied, the model did adjust well to changes made and according to the verification at lab it was seen that the model also worked for changes in pulp concentration and different brightness at the beginning of the stage.

The aim is to investigate models that predicts the potential of pulp and evaluate the relevance of the zero-span tensile index within these. Two chemical pulps made from softwood and eucalyptus were refined in a Voith-beater with different energy input in order to study the change of fiber morphology signals and other pulp and paper properties. Chemical, THP pulp from Södra Värö is also used as an initial analysis for morphological connections to Zero-span tensile index. The L&W Fiber Tester Plus is used in order to study the pulps fiber morphology and Pulmac 2000 for zero span. Handsheets are made for mechanical tests such as tensile properties, ZD-strength and optical properties. Many of the given signals change according to clear patterns with increasing refining energy. Using least square methods, formulas describing the development with high adaptation could be formulated. Many of the measured aspects changes over already known patterns. These are then applied in the models. Three possible models is tested: linear regression, Shear-Lag and Page. Of the three, only the two first ones where able to produce reliable models, whereas the third required data that was difficult to acquire at the same time as the adaptation was very low. The only model that use exclusively morphology data is linear regression.

Abstract Purpose Changing processes and an organization quickly and successfully is a challenging task. Thus, standardization of the process of making changes as well can be useful to reach the goal of increased performance. Many different aspects can be considered when investigating the critical factors that lead to a successful change. Assessing whether these critical factors can be utilized to formulate standards is, therefore, an interesting topic to delve deeper into. Thus, the purpose is “Explore how change management processes in the pulp and paper industry can be standardized, and how the change management process can be improved.” and the research questions (RQ):  RQ1. What are the critical factors of the change management processes in the pulp and paper industry?  RQ2. How can standardization of change management processes be achieved in the pulp and paper industry? Method This is a qualitative study where information has been gathered through a literature review and a multiple case study. The empirical data was primary data gathered through interviews. Theoretical information was gathered based on keywords selected through brainstorming sessions and found in articles. A data analysis model was used when analysing the empirical data.  Findings Six critical factors were found as an answer to RQ1. These six critical factors for pulp and paper industries were found within broader studies on change management factors as well. Standardization of change management processes on a general level was deemed possible. However, when investigating detailed levels of change management processes there are indications that it is possible to some degree, but it is more difficult to transfer a standardized process between different types of changes. Future Research More research can be beneficial in change management on more detailed levels and how standards can be transferred between types of change, and if this is only applicable to pulp and paper industries or to 24-hour continuous production processes. The conceptual maturity model presented in this report could be explored further and has the potential to be modified further to fit the needs of different organizations and industries. The conceptual guideline that was presented in the report needs to be tested and verified. Limitations This project has excluded international factories from its studied area. This project also scopes in toward the pulp and paper industry as its focus and did not analyse if its result is applicable to other industries or not. Additionally, this project did not verify if the implementation of the resulting guidelines yields a positive or negative outcome, further study is required.

Syftet med denna studie är att undersöka inverkan av förbehandlingar på ljushetsstabiliteten av Northern Bleached Softwood Kraft (NBSK) som har blekts enligt (OO) (OP) D/Dn (PO) bleksekvensen. Effekten av förbehandling med xylanas (X), mild sur (A), DTPA (Q) samt ett kombinerad DTPA- & xylanassteg (Q+X) har studerats.  Resultaten indikerar att Q+X förbehandlingen var mest effektiv i minskningen av skadliga metalljoner i massan. Den Q+X förbehandlade massan hade dessutom lägst kappa och högst ljushetsvärde bland förbehandlingarna. Kemisk sammansättningsanalys av de förbehandlade massorna visar vidare att den Q+X förbehandlingen ledde till den högsta minskningen av såväl xylan som lignin. Det milda A förbehandlingen var inte effektivt för att avlägsna alla viktiga skadliga metalljoner och visade ingen effekt på reduktionen av xylan eller lignin. Den X behandlade massan visade ingen förmåga att ta bort metaller och är därför ofördelaktigt.  Q och Q+X förbehandlade massaströmmar har blekts vidare för att studera effekterna av dessa förbehandlingar på den slutliga massakvaliteten samt för att jämföra ett konventionellt klordioxidsteg (D) och en nästan neutral pH klordioxidsteg (Dn). Resultaten bekräftar att Dn-steget ledder till en reducerad grad av AOX.  Ljusheten direkt efter klordioxidsteget är vidare högre för de Dn-behandlade massorna, men processen är begränsad med avseende på ljushetsstabilitet, vilket är en viktig nackdel.  Q+X (OP) D (PO) blekningssekvensen visade den högsta ljushetsstabilitet, medan den Q+X (OP) Dn (PO) blekningssekvensen visade ingen förbättring jämfört med Q (OP) Dn (OP) blekningssekvensen. Slutsatsen är att den enzymatisk medförda kvalitetsförbättringen inte räcker för att kompensera för bristerna i ett Dn-steg. / This is a study on Northern Bleached Softwood Kraft (NBSK) and the (OO) (OP) D/Dn (PO) bleaching sequence. The effects of a xylanase (X), mild acidic (A), DTPA (Q), and a combined DTPA & xylanase (Q+X) pre-treatments have been studied. The results indicate that the Q+X pre-treatment most effectively reduced the presence of harmful metal ions in the pulp. The Q+X pre-treated pulp furthermore yielded the lowest kappa number and highest brightness values among the pre-treatments tested. Chemical analysis of this pulp also shows the highest reduction in xylans and lignin. The mild A stage was ineffective in removing all harmful metal ions and showed no effect on the reduction of xylans or lignin. The X stage cannot meanwhile remove metals and is thus disadvantageous. Subsequently, the Q+X pre-treated pulp as well as a Q-treated pulp stream were further bleached to study the effects of these pre-treatments on the final pulp quality as well as to compare these streams of pulp bleached using a conventional chlorine dioxide stage (D) and a near neutral pH chlorine dioxide (Dn) stage. The results confirmed that the Dn stage causes a reduced degree of AOX in the effluent. Furthermore, the brightness directly after the chlorine dioxide stage is higher for the Dn-treated pulps but the process is limited in brightness stability which is a significant drawback. The Q+X (OP) D (PO) bleaching sequence showed the highest brightness stability while the Q+X (OP) Dn (PO) bleaching sequence displayed no improvement over the Q (OP) Dn (OP) bleaching sequence. The conclusion can be made that the enzymatic boost in bleaching is not enough to compensate for the shortcomings of a Dn stage.

Fluffmassa är ett förnybart material bestående av cellulosafiber som utvinns under massakokning. Dessa fiber används för att tillverka olika absorberande produkter som till exempel servetter. Fluffmassa används även för att tillverka absorptionskärnor i damhygienprodukter, inkontinensprodukter och blöjor. Vissa av dessa absorptionskärnor (speciellt i ultratunna bindor) tillverkas med airlaid. Airlaid är en tillverkingsteknik som ger fiberstrukturer med slumpmässig orientering genom att applicera ett undertryck.  Syftet med detta examensarbete var att utveckla metoder för att tillverka servetter och absorptionskärnor till damhygienprodukter i laboratoriemiljö genom att använda en airlaid maskin i laboratorieskala. Detta utfördes genom att analysera viktiga egenskaper som exempelvis ytvikt, tjocklek, densitet, böjlängd och förmågan att absorbera vätska i kommersiella servetter och absorptionskärnor inom damhygien. Även dragprov och SEM-analys utfördes. Resultatet från dessa analyser användes som ett riktvärde under metodutvecklingen.  Två metoder utvecklades - en för att tillverka en servettstruktur och en för att tillverka en absorptionskärna för damhygien. De olika tillverkningsstegen inkluderar defibrering, formering, pressning, prägling, latexsprayning samt härdning. Båda strukturerna tillverkades, och dess egenskaper analyserades och jämfördes med de kommersiella produkterna. Analyserna visade att de utvecklade metoderna genererade struktuer vars ytvikt stämde väl överrens med de kommersialla produkterna. Strukturerna var dock tjockare och hade en lägre densitet än de kommmersiella produkterna. Den minskade densiteten påverkade förmodligen resultatet från de andra analyserna som utfördes i detta projekt. Servettstrukturen hade en lägre böjlängd än de kommersiella servetterna och damhygienstrukturen hade bättre absorption än de kommersiella produkterna.  Båda strukturerna hade en ytfinish som överensstämmde väl med de kommersiella produkterna. Dock visade SEM-analysen att latex saknades i mitten av de båda tillverkade strukturerna. / Fluff pulp is a renewable material consisting of pure cellulose fibers which are obtained during pulping. These fibers are commonly used to form Airlaid-nonwoven products such as napkins and wipes. Fluff pulp is also used in absorbent cores in femcare products, incontinence products and diapers. Some of these absorbent core structures (especially in ultrathin pads) are produced through airlaid. Airlaid is a manufacturing technique which forms a randomly oriented fiber structure by using an applied suction.  This degree project aimed at developing methods for producing napkins and femcare absorbent cores on a laboratory scale by using an airlaid former. Important properties such as grammage, thickness, density, bending length and absorption capacity were therefore measured on commercial napkins and femcare absorbent cores. Other analyses which were performed include tensile testing and SEM. Findings from these analyses were then used as a target reference during the method development.  Two methods were developed; one for producing a napkin structure and one for producing a femcare absorbent core structure. The different manufacturing steps included fiber defiberization, sample formation, pressing, embossing, latex spraying and curing. Napkin structures and femcare absorbent core structures were produced by using the developed methods, and their properties were analyzed and compared with the commercial products.  Analysis showed that the developed methods generated structures with grammages that corresponded well with the grammages in the commercial products. However, both developed structures were thicker and had lower density than the commercial products. This decreased density probably influenced the results in other analyses performed in this project. The developed napkin structure had a shorter bending length compared to the commercial napkins and the developed femcare structure had a better absorption capacity compared to the commercial femcare absorbent cores. Both developed structures obtained nice surface finish which corresponded well with the surface finish in the commercial products. However, SEM analysis indicated that no latex managed to reach the center in the developed structures.

Submitted in fulfillment of the requirements for the degree of Doctor of Technology: Chemistry, Durban University of Technology, Durban, South Africa, 2015. / This thesis forms part of the Council for Scientific and Industrial Research, Forestry and Forest Products Research Centre (CSIR-FFP) biorefinery project which aims at developing and implementing novel industrial processes production of cellulose textile fibres. The focus of this study is to investigate the dissolution of South African Eucalyptus raw (unbleached) and final (bleached) dissolving pulp and saw dust wood in an ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate [Emim][OAc] and the co-solvents [dimethylsulfoxide (DMSO)] or [dimethylformamide (DMF)] mixtures, to obtain regenerated cellulose by the further addition of water and acetone. The IL/co-solvent mixtures were able to dissolve the raw and final pulp samples at 120 ˚C for 6 hours whereas the sawdust wood dissolved in 10 hours. The IL/DMF mixture gave higher cellulose recoveries of 41.88 % for the raw pulp, 49.89 % for the final pulp sample and 32.50 % for sawdust wood while the IL/DMSO mixture gave a recovery of 15.25 % for the raw pulp sample, 36.25 % for the final pulp sample and 17.83 % for the sawdust wood sample. The regenerated cellulose materials were characterized by Fourier Transformer Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Scanning Electron Microscopy (SEM), Thermo gravimetric Analysis (TGA) and Powder X-Ray Diffraction (pXRD), and compared with a standard microcrystalline of cellulose. It was observed that the FTIR and NMR spectra of the regenerated cellulose and MCC were similar which then indicates that no chemical reaction occurred during the dissolution and regeneration process of cellulose. SEM and X-ray diffraction (XRD) patterns of the results showed that after dissolution the cellulose I (native form), the crystalline structure was completely converted into cellulose II (amorphous) structure, and this was due to the removal of lignin and decrease in cellulose crystallinity. TGA results showed that the regenerated cellulose samples have higher char yields compared to the MCC which is due to the IL remaining in the regenerated cellulose. It was also observed that the addition of the co-solvents decreased the viscosity of the IL mixture, facilitating dissolution of the cellulose that led to additional swelling and reduction of the recalcitrant nature of the cellulose crystalline structure and intermolecular interactions. This led to increased accessibility and dissolution of the cellulose. The findings in this study have the potential to bring ILs closer to applications for biomass technology in particular for an economically viable dissolution method for biomass because ILs have a benefit of being easily separated from the anti-solvent, which provides a simple solution for IL recycle ability and re-use. The novel aspect of this study is: . This is the first study in the South African context to examine the influence of the lignin on the dissolution and regeneration of Eucalyptus sawdust wood and dissolving pulp. / D

Le coiffage pulpaire direct, dans des situations pathologiques critiques où la vitalité de la dent est menacée, vise à stimuler le potentiel de cicatrisation de la pulpe et induire une régénération dentinaire. Afin d'optimiser cette thérapeutique, le Laboratoire IMEB-ERT 30 a développé en partenariat avec la société SEPTODONT un nouveau matériau, le Biodentine™. Ce ciment, composé essentiellement de silicate tricalcique, possède des qualités physiques permettant son utilisation comme substitut dentinaire. Le premier objectif de notre travail a été d'évaluer les propriétés biologiques du Biodentine™ et ses interactions avec les cellules cibles en culture. La bioactivité du nouveau ciment a ensuite été étudiée à l'aide du modèle de culture de dents entières humaines ex vivo. Ce modèle expérimental original a été mis au point dans notre laboratoire et permet d'étudier les phases précoces de la régénération dentinaire lors du coiffage direct. Grâce à ce modèle, nous avons démontré l'activation, la prolifération et la migration de cellules progénitrices pulpaires périvasculaires en réponse à une lésion cavitaire profonde. Le coiffage direct avec les ciments de silicates tricalciques a induit la formation de foyers minéralisés à proximité de la lésion. La caractérisation moléculaire de ces foyers a montré qu'il s'agit d'une forme de dentine réparatrice synthétisée par des cellules odontoblast-like. Le deuxième objectif de notre travail a été d'étudier l'effet du nouveau biomatériau sur la sécrétion de certains facteurs de croissances, impliqués dans les phases précoces de la cicatrisation pulpaire, et de le comparer à celui d'autres matériaux de coiffage. / The objective of direct pulp capping is to stimulate the pulp healing potential and to induce dentin regeneration. This is of prime importance in critical pathologic situations compromising the tooth vitality. To improve the outcome of this treatment, the IMEB-ERT30 Laboratory, in collaboration with the SEPTODONT Company, has developed a new restorative material called Biodentine™. This cement, essentially composed of tricalcium silicates, has the required physical properties to be used as a dentin substitute. The first aim of this work was to evaluate the biological properties of Biodentine™ and its interactions with the target cells in cell culture. Then, the bioactivity of the new cement was studied using an entire human tooth culture model ex vivo. This original experimental model, developed in our Laboratory, is suitable in studying the early steps of dentin regeneration after direct pulp capping. With this model, we demonstrated the activation, proliferation, and migration of perivascular pulpal progenitor cells in response to pulp injury. The direct pulp capping with tricalcium silicate cements induced mineral foci formation in the vicinity of the pulp lesion. Molecular characterization of these foci confirmed it was of a reparative dentin type produced by odontoblast-like cells. The second objective of our work was to study the effect of the new cement on the secretion of some growth factors involved in the early steps of pulp wound healing, and compare it to that of other pulp capping materials. The results demonstrated an up-regulation of b-FGF, VEGF and PDGF-AB secretion in response to the target cells injuries, suggesting a stimulation of angiogenesis.

A Dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree Of Master of Science in Medicine, 2016. / Dental stem cells (DSCs) have been identified in teeth and their supporting tissues. They represent an exclusive source of adult stem cells, easily isolated and manipulated for tissue repair and regeneration. This research project evaluated the neurogenic potential of the dental pulp stem cells (DPSCs) and stem cells from the pulp of human exfoliated deciduous teeth (SHEDs) in a South African cohort. Sixty non-carious permanent and deciduous teeth were extracted from healthy patients aged between 18 and 30 years and 5 and 10 years, at the University of the Witwatersrand's Oral Health Clinic in Johannesburg Charlotte Maxeke Academic Hospital, South Africa. The cells, isolated from the extracted pulp tissue were cultured, counted and then phenotyped by flow cytometry analysis. The cells were further expanded in a neural induction medium and immunocytochemistry analysis for Ki-67, doublecortin (DCX) and nestin were performed. Large colonies of both DPSCs and SHEDS were harvested from the extracted pulp tissues and positively cultured. Flow cytometry analysis confirmed the presence of CD44+ and CD29+ cells as well as the known mesenchymal stem cell markers CD90 and CD105. Both DPSCs and SHEDs demonstrated successful proliferation and neural differentiation. This study confirmed that DPSCs and SHEDs are highly proliferative human adult stem cells that exhibit a neurogenic potential that may contribute in the treatment of neurological disorders. / AC2017

Este estudo translacional avaliou o efeito da aplicação direta de materiais capeadores à base de óleo de copaíba sobre a polpa dentária de ratos. O biomaterial foi analisado de acordo com os processos inflamatórios, reparadores e regenerativos. Cavidades classe I foram preparadas na face oclusal dos molares superiores e inferiores de ratos da linhagem Wistar (n=120). Posteriormente, uma cavidade padronizada foi realizada com broca carbide esférica ¼. Exposições pulpares foram obtidas e após a hemostasia com algodão estéril e água destilada, foi realizado o capeamento pulpar com aplicação de biomateriais diretamente no tecido pulpar. Os biomateriais utilizados foram: COP (Óleo de Copaíba); Ca(OH)2 (hidróxido de cálcio), Ca(OH)2+COP; MTA (agregado trióxido mineral); MTA+COP; BIODENTINA (Biodentine®); BIODENTINA+COP. Todas as cavidades foram restauradas com cimento provisório. Os animais foram sacrificados após o período de 7, 14, 28 dias de acordo com os princípios de ética e experimentação animal. Vinte e um grupos foram criados a partir da combinação de tempos e materiais, cada grupo foi constituído de 5 animais. As peças foram preparadas e processadas pela técnica histológica e coradas pela HE (hemotoxilina e eosina) realizando cortes aleatórios, sendo analisados ao microscópio óptico em 100X de aumento por 2 examinadores. Os critérios avaliados foram: respostas inflamatória e degenerativa, organização tecidual, dentina reacional e reparativa. No último tempo experimental (28 dias) de todos os grupos foi analisado a superfície (mm2) e o volume (mm3) da ponte de dentina formada pela técnica da micro-CT (microtomografia computadorizada) de alta resolução. Os dados foram estatisticamente analisados utilizando o teste T pareado, determinando a superfície e volume da dentina reparadora formada entre os grupos experimentais. Nas análises histológicas foi utilizado o teste não-paramétrico de Mann-Whitney realizando comparações entre os grupos (?=5%). A BIODENTINA demonstrou uma tendência de acelerar o processo de regeneração pulpar, iniciando a deposição de dentina reparativa ao sétimo dia do capeamento. Este material apresentou uma dentina mais espessa em comparação com os outros biomateriais. O MTA também demonstrou uma eficiência na formação da ponte dentinária, entretanto em 20% das amostras não foi observada a presença de dentina reparadora. Ao acrescentar o COP nestes materiais, a formação da ponte dentinária apresentava heterogênea e incompleta, além disso esses grupos continham um processo inflamatório aumentado. A dentina reparadora do grupo de Ca(OH)2 demonstrou presença de túnel, com característica heterogênea. A adição do COP ao Ca(OH)2 aumentou a formação de dentina nas paredes ao redor da câmara pulpar em 80% das amostras, porém esta dentina não apresentava melhora na qualidade. Desta forma, o capeamento pulpar com COP isolado ou associado a Ca(OH)2, MTA e BIODENTINA não formou uma ponte de dentina completa e homogênea no local da exposição pulpar. / This translational study evaluated the effect of the direct application of copaiba oil based capping materials on the rat pulp. The biomaterial was analyzed according to inflammatory, repairing and regenerative processes. Class I cavities were prepared on the occlusal surface of the upper and lower molars of Wistar rats (n = 120). Subsequently, standardized cavities was performed with ¼ spherical carbide drill. Pulp exposures were obtained and after their hemostasis with sterile cotton and distilled water, pulp capping was done with application of biomaterials directly on the pulp tissue. The biomaterials used were: COP (Copaíba oil); Ca(OH)2 (calcium hydroxide), Ca(OH)2+COP; MTA (aggregate mineral trioxide); MTA+COP; BIODENTINE (Biodentine®); BIODENTINA+COP. All cavities were restored with temporary cement. The animals were sacrificed after the period of 7, 14, 28 days according to the principles of ethics and animal experimentation. Twenty-one groups were created from the combination of times and materials, each group consisted of 5 animals. The specimens were prepared and processed by histological technique and stained by HE (haemotoxin and eosin); randomized cuts were examined under optical microscope with 100X enlargement by two different examiners. The evaluated criteria were inflammatory and degenerative response, tissue organization, reactive and reparative dentin. In the last experimental period (28 days) of all groups, the surface (mm2) and the volume (mm3) of the reactive and reparative dentin formed were analyzed by the high-resolution micro-CT (computerized microtomography) technique. The data were statistically analyzed using the paired T-test, determining the surface and volume of the reparative dentin formed between the experimental groups. In the histological analyzes, the non-parametric Mann-Whitney test was used, comparing groups (? = 5%). BIODENTINE demonstrated a tendency to accelerate the process of pulpal regeneration, initiating the deposition of reparative dentin on the seventh day of the capping. This material had a thicker dentin compared to the other biomaterials. The MTA also demonstrated an efficiency in the formation of the dentin bridge; however, 20% of the samples did not observe the presence of reparative dentin. When adding the COP in these materials, the formation of the dentin bridge was heterogeneous and incomplete, in addition these groups contained an increased inflammatory process. The repair dentin of the Ca(OH)2 group showed a tunnel with a heterogeneous characteristic. The addition of COP to Ca(OH)2 increased dentin formation in the walls around the pulp chamber in 80% of the samples, but this dentin did not show improvement in quality. Thus, pulp cap with COP isolated or associated with Ca(OH)2, MTA and BIODENTINE did not form a complete and homogeneous dentin bridge at the site of pulp exposure.

Estudos de diagnóstico de vitalidade pulpar em dentes decíduos traumatizados, através da Fluxometria Laser Doppler (FLD), têm utilizado dentes tratados endodonticamente, porém o diagnóstico clínico é realizado em dentes necrosados. O objetivo deste estudo foi avaliar a FLD como teste de vitalidade pulpar em incisivos superiores decíduos traumatizados necrosados, desvitalizados (DES), antes e após tratamento endodôntico. Foram analisados em 57 crianças, de 40 a 85 meses de idade, valores de fluxo de dois dentes: IC DES - I VIT - 1 incisivo central necrosado (leitura antes e após a endodontia) e 1 incisivo central ou lateral vitalizado (leitura repetida em 2 sessões); I VIT - I VIT - 2 incisivos centrais ou laterais vitalizados (leitura em sessão única). Foi utilizado o Fluxômetro Laser Doppler (Moor Instruments, moorLab, Axminster, Inglaterra), diodo laser emitindo no comprimento de onda de 780nm, banda Doppler em 15kHz, sonda MP13 posicionada na vestibular a 4mm da margem gengival e estabilizada com posicionador de silicone. Foram avaliados dois parâmetros: F(UA), valor de fluxo de um único dente em unidades arbitrárias; F(%), variação percentual entre pares de dentes de um mesmo paciente. Estes parâmetros foram aplicados nos grupos antes e após a endodontia: F(UA) antes, F(UA) após, F(%) antes e F(%) após. No parâmetro F(UA), para os 29 IC DES antes, a variação de fluxo foi de 2,3 a 11,1UA, a média foi de 5,4UA e o desvio-padrão de 2,5UA. Para os 29 I VIT antes, a variação foi de 4,2 a 16,1UA (9,6 ± 3,5UA). Na segunda sessão, para os 29 IC DES após, foi de 1,3 a 7,4UA (3,4 ± 1,6UA), e para os 29 I VIT após foi de 3,6 a 19,7UA (9,3 ± 3,6UA). Para os 62 I VIT analisados em única sessão, a variação foi de 5,0 a 16,5UA (9,3 ± 2,4UA). No parâmetro F(%), para os 29 pares de IC DES antes - I VIT antes a variação foi de 28,0 a 98,1% (57,4 ± 17,2%). Para os 29 pares de IC DES após - I VIT após, de 18,0 a 84,5% (37,9 ± 15,2%). Para os 31 pares de I VIT - I VIT, foi de 57,5 a 146,5% (99,9 ± 23,3%). A performance dos parâmetros foi estimada pela área sob a curva ROC (AUC). Para F(UA) antes, a AUC foi de 0,862, para F(%) antes, a AUC foi de 0,941, para F(UA) após, a AUC foi de 0,975. Seus desempenhos, considerando intervalo de confiança de 95%, foram considerados entre moderadamente acurados e altamente acurados. Para F(%) após, a AUC foi de 0,987, sendo seu desempenho altamente acurado. Após comparação das AUCs, somente foi observada diferença significante, p=0,002, entre F(UA) antes e F(UA) após. Os pontos de corte propostos foram baseados nos dados obtidos antes da endodontia: para F(UA), valores menores ou iguais a 6,5UA classificam os dentes como desvitalizados e para F(%), valores menores ou iguais a 66,9%. Conclui-se que F(UA) e F(%) são parâmetros capazes de diferenciar dentes decíduos necrosados de dentes vitalizados, assim como de diferenciar dentes tratados endodonticamente de dentes vitalizados. / Studies on diagnosis of dental pulp necrosis in traumatized primary teeth using laser Doppler flowmetry (LDF) evaluate teeth with endodontic treatment; however, clinical diagnosis is performed in teeth with pulp necrosis. The aim of this study was to evaluate the LDF as pulp vitality test in traumatized primary upper incisors, with pulp necrosis (DES), before and after endodontic treatment. The pulpal flux values of 57 children, aged from 40 to 85 months, were evaluated: IC DES - I VIT - 1 central incisor with pulp necrosis (readings before and after endodontic treatment) and 1 vital central or lateral incisor (readings in 2 sessions); Control group: I VIT - I VIT - 2 vital incisors (readings in 1 session). The Laser Doppler Flowmeter (Moor Instruments, moorLab, Axminster, UK) was used. It is a diode laser emitting at 780 nm and bandwidth at 15 kHz. A MP13 probe was placed on the buccal surface of the tooth, 4mm from the gingival margin using silicone splints. Two parameters were evaluated: F(AU), the flux value of each tooth in arbitrary units, and F(%), the percentage variation of the flux value between pairs of teeth in the same patient. The two parameters were used before and after endodontic treatment: F(AU) before, F(AU)after, F(%) before and F(%) after. In the 29 IC DES before, F(AU) ranged from 2.3 to 11.1AU; the mean was 5.4AU and the standard deviation was 2.5AU; in the 29 I VIT before, ranged from 4.2 to 16.1AU (9.6 ± 3.5AU); in the 29 IC DES after, the values ranged from 1.3 to 7.4AU (3.4 ± 1.6AU), and in the 29 I VIT after, from 3.6 to 19.7AU (9.3 ± 3.6AU). In the 62 I VIT analyzed in one session, the values ranged from 5.0 to 16.5AU (9.3 ± 2.4AU). In respect to F(%), in the 29 pairs of IC DES before - I VIT before, the values ranged from 28.0 to 98.1% (57.4 ± 17.2%); in the 29 pairs of IC DES after - I VIT after, from 18.0 to 84.5% (37.9 ± 15.2%); in the 31 pairs of I VIT - I VIT, from 57.5 to 146.5% (99.9 ± 23.3%). The performance of both tests was estimated by the area under the ROC curve (AUC). Regarding F(AU) before, the AUC was 0.862; in F(%) before, the AUC was 0.941; in F(AU) after, the AUC was 0.975. The performances were classified between moderate and highly accurate (95% Confidence Interval). Regarding F(%) after, the AUC was 0.987 and its performance was highly accurate. Comparing the AUCs, there was statistical significance (p=0.002), between F(AU) before and F(AU) after. The cut-off values were based on data before endodontic treatment. The F(AU) values that were equal to or smaller than 6.5AU, and the F(%) values that were equal to or smaller than 66.9% classified the tooth as non-vital The two parameters studied, F(AU) and F(%), are able to distinguish non-vital primary teeth from vital teeth, and to distinguish vital teeth from teeth with endodontic treatment.