<p>Rapid wound healing is important to regain the skins protective function after injury. Studies have shown that enamel matrix proteins (EMP) have many desirable effects which may accelerate wound healing [Bosshardt <em>et al.</em> 2008].</p><p> </p><p>Polymers (Polymer A, B and C) were formed into a mat form, with or without incorporated enamel matrix derivative (EMD) (Collaboration partner). The materials may be suitable for wound care and drug delivery systems.</p><p> </p><p>Protein release tests were performed on samples incubated in physiological-like solution using pyrogallol red staining, ultraviolet (UV) spectrophotometer and high-performance liquid chromatography (HPLC). Protein was detected in Polymer A material samples, compared to a reference material sample, using pyrogallol red staining. An in vitro experiment showed that normal human dermal fibroblasts (NHDF) cultivated with Polymer A material (with EMD) had significantly higher viability than NHDF cultivated with reference material (Polymer A without EMD) and comparable viability to fibroblasts grown with either 0.1 mg EMD in solution or with 10% fetal calf serum. Images taken of Polymer A material, with incorporated Fluorescein isothiocyanate- (FITC) labeled EMD, indicate a homogenous distribution of EMD peptides and/or EMD aggregates throughout the material. A dressing which contains an active substance may have clinical promise for wound care applications.</p>

Rapid wound healing is important to regain the skins protective function after injury. Studies have shown that enamel matrix proteins (EMP) have many desirable effects which may accelerate wound healing [Bosshardt et al. 2008]. Polymers (Polymer A, B and C) were formed into a mat form, with or without incorporated enamel matrix derivative (EMD) (Collaboration partner). The materials may be suitable for wound care and drug delivery systems. Protein release tests were performed on samples incubated in physiological-like solution using pyrogallol red staining, ultraviolet (UV) spectrophotometer and high-performance liquid chromatography (HPLC). Protein was detected in Polymer A material samples, compared to a reference material sample, using pyrogallol red staining. An in vitro experiment showed that normal human dermal fibroblasts (NHDF) cultivated with Polymer A material (with EMD) had significantly higher viability than NHDF cultivated with reference material (Polymer A without EMD) and comparable viability to fibroblasts grown with either 0.1 mg EMD in solution or with 10% fetal calf serum. Images taken of Polymer A material, with incorporated Fluorescein isothiocyanate- (FITC) labeled EMD, indicate a homogenous distribution of EMD peptides and/or EMD aggregates throughout the material. A dressing which contains an active substance may have clinical promise for wound care applications.

The process of osseointegration described by Brånemark (Brånemark et al 1969, 1977) and Schroeder (Schroeder et al 1981) plays an integral role in dental rehabilitation. Since the first observation 40 years ago, osseointegrated titanium implants have been used predictably in the dental rehabilitation of fully edentulous patients. The application of dental implants has evolved, and from the 1980s dental implants have been used increasingly in the treatment of partially edentulous patients, with equal or better long-term success (Buser et al 1990, 1997, Lekholm et al 1994, Behneke et al 2000, Bornstein et al 2005). The surgical procedures for the placement of endosseous dental implants are based on the original work by Brånemark and colleagues approximately 40 years ago. The two-stage surgical procedure was originally advocated to obtain an optimal process of new bone formation and remodelling after implant placement (Brånemark et al 1977). Osseointegration and good long-term success was also found to be achievable with non-submerged implants (Buser et al 1990, 1992, 1997, Ericsson et al 1997) with the added advantage of avoiding a second surgical procedure (Buser et al 1999). Implant dentistry has evolved over the last 15 years and has benefited from significant progress made in associated treatment protocols and the development of bone augmentation procedures (guided bone regeneration (GBR) and sinus floor elevation) allowing for correction of alveolar bone deficiencies. Additionally, improved osteophilic microtextured implant surfaces have been developed to accelerate healing, significantly reducing treatment time. Research and clinical focus in dental implantology in the last two decades has primarily concentrated on the bone-to-implant interface of osseointegrated implants. The soft tissue profile and seal around implants have been investigated to a much lesser degree. This interest has been largely due to the fact that a successfully osseointegrated implant depends on anchorage in bone and requires a direct bone-to-implant interface to provide long-term support for a prosthesis. Both bone and soft tissue integration onto dental implants are wound healing processes whereby several stages of tissue formation and degradation are involved (Berglundh et al 2003, Abrahamsson et al 2004). Osseointegration is the result of the modelling and remodelling of bone tissue that occurs after implant placement whilst the wound healing that occurs following the closure of mucoperiosteal flaps during implant surgery results in the establishment of a mucosal attachment (transmucosal attachment) to the implant. The establishment of the mucosal barrier around the implant is characterised by the gradual shift from a coagulum to granulation tissue followed by the formation of a barrier epithelium and the maturation of the connective tissue (Berglundh et al 2007). Like natural teeth, osseointegrated implants are transmucosal “masticatory devices” that penetrate the oral mucosa with the periodontal and peri-implant tissues expected to perform a protective function (Weber & Cochran 1998). Background: Peri-implant tissues form a crucial but fragile seal between the oral environment, the bone and the implant surface. Enhancing the seal formed by the peri-implant soft tissues at the titanium/connective tissue interface may be an important factor in implant survival. Additionally, enhancing soft tissue adherence to the implant surface when implants are placed in dehiscence type defects may mean that simultaneous osseous grafting procedures will not always be required. Objective: The aim of this study was to investigate the effect of implant surface modification with either platelet-derived growth factor (PDGF) or enamel matrix derivative (EMD) on the connective tissue attachment to moderately roughened titanium implants. Material and Methods: 18 moderately roughened titanium implants were subcutaneously implanted into 14 rats. 6 implants each were coated with PDGF and EMD immediately prior to implantation and 6 implants were left uncoated. The implants were retrieved with a sample of surrounding tissue at 4 and 8 weeks. The specimens were resin-embedded and sections viewed under confocal microscopy for collagen autofluorescence and prepared for qualitative and histomorphometric analysis under light microscopy. ANOVA and t-tests were used to compare the thickness of fibroblast encapsulation on the implant surface and the depth of connective tissue penetration onto the implant grooves. Results: Qualitative analysis under confocal and light microscopy showed encapsulation of all implants by fibroblasts and good soft tissue integration at the end of 4 and 8 weeks. Coating of the implants with growth factors did not alter the orientation of fibroblasts and collagen fibres. Histomorphometric analysis demonstrated that the depth of connective tissue penetration into the implant grooves was significantly greater for the implants coated with PDGF at 4 weeks (ANOVA, P value 0.0014). The thickness of the fibroblast encapsulation on the implant surface was significantly less for the implants coated with PDGF at 8 weeks (ANOVA, P value 0.0012). Conclusion: Good soft tissue integration can be achieved on a moderately roughened titanium implant surface. Coating the implant surface with rhPDGF-BB could increase the speed of soft tissue healing around an implant surface but this increased rate of healing with rhPDGF-BB coating could also result in a less robust titanium/connective tissue interface. / Thesis (D.Clin.Dent.) -- University of Adelaide, School of Dentistry, 2010

O objetivo do presente estudo foi avaliar histopatologicamente, a resposta dos tecidos pulpar e periapical de dentes de cães, após pulpotomia e proteção do remanescente pulpar com o Derivado da Matriz do esmalte (Emdogain®). Foram utilizados 40 dentes (80 raízes), de 4 cães, distribuídos em 6 grupos, nos períodos experimentais de 7 dias (Grupos I, II e II) e 70 dias (Grupos IV, V e VI). Após a remoção da polpa coronária, o remanescente pulpar foi recoberto com os seguintes materiais: Grupo I e IV - Derivado da Matriz do Esmalte (Emdogain®); Grupos II e V (Controle negativo) pasta de Hidróxido de Cálcio p.a. e soro fisiológico e Grupos III e VI (Controle positivo) Óxido de Zinco e Eugenol. Decorridos os períodos experimentais, os animais foram submetidos à eutanásia, as peças removidas e submetidas ao processamento histológico. A avaliação microscópica foi realizada em microscópio óptico com relação à presença ou não da barreira dentinária, severidade da inflamação, presença ou ausência de hemorragia, presença ou ausência de osteogênese focal, presença ou ausência de necrose pulpar, presença de reabsorção radicular externa e espessura do ligamento periodontal. A avaliação radiográfica foi realizada considerando-se a integridade da lâmina dura, presença de áreas de rarefação óssea periapical, de reabsorção radicular (interna e externa) e de ponte de dentina. Os resultados obtidos foram submetidos à análise estatística utilizando-se o teste exato de Fisher (&alpha;= 0,05). Nos espécimes que apresentavam lesões periapicais, as medidas radiográficas das áreas de rarefação óssea periapical foram comparadas entre grupos por meio do teste de Kruskal-Wallis seguido pelo pós teste de Dunn (&alpha;= 0,05). Os achados histopatológicos evidenciaram que no período de 7 dias, no Grupo I havia um infiltrado inflamatório leve a moderado e intensa proliferação vascular no tecido pulpar, no Grupo II um infiltrado inflamatório leve, estando o tecido pulpar íntegro enquanto no Grupo III foi observado um infiltrado inflamatório moderado a severo. Em todos os grupos não havia formação de ponte de dentina e a região periapical apresentava aspectos de normalidade. No período de 70 dias, nos Grupos IV e VI não houve formação de ponte de dentina, o tecido pulpar apresentava áreas de necrose com presença de células inflamatórias na região periapical e reabsorção cementária e óssea. Por outro lado, no Grupo V, foi observada a presença de ponte de dentina, ausência de processo inflamatório e ausência de reabsorção dos tecidos mineralizados. Com relação aos achados radiográficos, no período de 7 dias, todos os Grupos (I, II e III) apresentaram integridade da lâmina dura, ausência de rarefação óssea periapical, ausência de reabsorção interna e externa e ausência de formação de ponte dentinária. No período experimental de 70 dias, o Grupo IV apresentou descontinuidade de lâmina dura com presença de rarefação óssea periapical em 100% dos casos. Ainda, reabsorção radicular interna e formação de ponte dentinária não foram observadas, com reabsorção radicular externa presente em 75% dos casos. Nos Grupos V e VI, a ausência de integridade da lâmina dura e presença de rarefação periapical foram observadas em 25% e 50% dos casos, respectivamente, e reabsorção radicular externa em 25% dos casos. Reabsorção radicular interna e formação de ponte dentinária não foram observadas em nenhum dos grupos. Os resultados microscópicos e radiográficos permitiram concluir que o Derivado da Matriz do Esmalte (Emdogain®) não apresentou resultados satisfatórios quando aplicado sobre o tecido pulpar exposto na técnica da pulpotomia. / The purpose of this study was to evaluate, both histopatologically and radiographically, the pulpal and periapical response of dogs´ teeth after pulpotomy and use of Enamel Matrix Derivative (Emdogain®). For such purpose, 40 teeth (80 roots), obtained from 4 dogs, were assigned to 6 groups and evaluated in two experimental periods: 7 days (Groups I, I, and III) and 70 days (Groups IV, V and, VI). After pulpotomy, pulp remnant was covered with the following materials: Groups I and IV Enamel Matrix Derivative (Emdogain®); Groups II and V (negative control) Calcium hydroxide p.a.; and Groups III and VI (positive control) Zinc oxide and eugenol. At the established experimental periods, the animals were euthanized and the anatomic pieces were obtained and histologically processed. The microscopic evaluation was performed in a light microscope regarding the presence or absence of induced dentin barrier, severity of inflammation, presence or absence of bleeding, presence or absence of focal osteogenesis, presence or absence of pulp necrosis, presence of external root resorption and periodontal ligament thickness. Radiographic evaluation was performed considering the integrity of the lamina dura, presence of areas of periapical bone rarefaction, root resorption (internal and external) and dentin bridge formation. The results were analyzed statistically using Fisher´s exact test (&alpha;= 0.05). In the specimens presenting apical periodontitis, the areas of the lesions were determined and the groups were compared using the Kruskal-Wallis test followed by Dunn test (&alpha;= 0.05). The histopathologic findings in the 7-day period revealed that Group I presented a mild to moderated inflammatory infiltrate and intense vascular proliferation in the pulp tissue; Group II presented a mild inflammatory and an intact pulp tissue, while Group III presented a moderate to severe inflammatory infiltrate. In all groups, there was no dentin bridge formation and the periapical region had normal appearance. In the 70-day period, Groups IV and VI showed no dentin bridge formation and pulp tissue presented necrotic areas with inflammatory cells in the periapical region as well as bone and cemental resorption. On the other hand, in Group V, there was dentin bridge formation, absence of inflammatory process and absence of resorption of mineralized tissues. Regarding the radiographic findings, in the 7-day period, all specimens in Groups I, II e II present intact lamina dura, absence of periapical bone rarefaction, absence of root resorption (internal and external) and absence of dentin bridge formation. In the experimental 70-day period, Group IV showed discontinuity of the lamina dura and presence of periapical bone rarefaction in 100% of cases. Internal root resorption and dentin bridge formation were not observed, with external root resorption in 75% of cases. In Groups V and VI, absence of hard layer and presence of periapical bone rarefaction were observed in 25% and 50% of cases, respectively and external root resorption in 25% of cases. Presences of internal root resorption and dentin bridge formation were not observed in any group. Based on these results, it may be concluded that Enamel Matrix Derivative (Emdogain®) did not present satisfactory results when applied on the pulp tissue following pulpotomy.

O objetivo do presente estudo foi avaliar histopatologicamente, a resposta dos tecidos pulpar e periapical de dentes de cães, após pulpotomia e proteção do remanescente pulpar com o Derivado da Matriz do esmalte (Emdogain®). Foram utilizados 40 dentes (80 raízes), de 4 cães, distribuídos em 6 grupos, nos períodos experimentais de 7 dias (Grupos I, II e II) e 70 dias (Grupos IV, V e VI). Após a remoção da polpa coronária, o remanescente pulpar foi recoberto com os seguintes materiais: Grupo I e IV - Derivado da Matriz do Esmalte (Emdogain®); Grupos II e V (Controle negativo) pasta de Hidróxido de Cálcio p.a. e soro fisiológico e Grupos III e VI (Controle positivo) Óxido de Zinco e Eugenol. Decorridos os períodos experimentais, os animais foram submetidos à eutanásia, as peças removidas e submetidas ao processamento histológico. A avaliação microscópica foi realizada em microscópio óptico com relação à presença ou não da barreira dentinária, severidade da inflamação, presença ou ausência de hemorragia, presença ou ausência de osteogênese focal, presença ou ausência de necrose pulpar, presença de reabsorção radicular externa e espessura do ligamento periodontal. A avaliação radiográfica foi realizada considerando-se a integridade da lâmina dura, presença de áreas de rarefação óssea periapical, de reabsorção radicular (interna e externa) e de ponte de dentina. Os resultados obtidos foram submetidos à análise estatística utilizando-se o teste exato de Fisher (&alpha;= 0,05). Nos espécimes que apresentavam lesões periapicais, as medidas radiográficas das áreas de rarefação óssea periapical foram comparadas entre grupos por meio do teste de Kruskal-Wallis seguido pelo pós teste de Dunn (&alpha;= 0,05). Os achados histopatológicos evidenciaram que no período de 7 dias, no Grupo I havia um infiltrado inflamatório leve a moderado e intensa proliferação vascular no tecido pulpar, no Grupo II um infiltrado inflamatório leve, estando o tecido pulpar íntegro enquanto no Grupo III foi observado um infiltrado inflamatório moderado a severo. Em todos os grupos não havia formação de ponte de dentina e a região periapical apresentava aspectos de normalidade. No período de 70 dias, nos Grupos IV e VI não houve formação de ponte de dentina, o tecido pulpar apresentava áreas de necrose com presença de células inflamatórias na região periapical e reabsorção cementária e óssea. Por outro lado, no Grupo V, foi observada a presença de ponte de dentina, ausência de processo inflamatório e ausência de reabsorção dos tecidos mineralizados. Com relação aos achados radiográficos, no período de 7 dias, todos os Grupos (I, II e III) apresentaram integridade da lâmina dura, ausência de rarefação óssea periapical, ausência de reabsorção interna e externa e ausência de formação de ponte dentinária. No período experimental de 70 dias, o Grupo IV apresentou descontinuidade de lâmina dura com presença de rarefação óssea periapical em 100% dos casos. Ainda, reabsorção radicular interna e formação de ponte dentinária não foram observadas, com reabsorção radicular externa presente em 75% dos casos. Nos Grupos V e VI, a ausência de integridade da lâmina dura e presença de rarefação periapical foram observadas em 25% e 50% dos casos, respectivamente, e reabsorção radicular externa em 25% dos casos. Reabsorção radicular interna e formação de ponte dentinária não foram observadas em nenhum dos grupos. Os resultados microscópicos e radiográficos permitiram concluir que o Derivado da Matriz do Esmalte (Emdogain®) não apresentou resultados satisfatórios quando aplicado sobre o tecido pulpar exposto na técnica da pulpotomia. / The purpose of this study was to evaluate, both histopatologically and radiographically, the pulpal and periapical response of dogs´ teeth after pulpotomy and use of Enamel Matrix Derivative (Emdogain®). For such purpose, 40 teeth (80 roots), obtained from 4 dogs, were assigned to 6 groups and evaluated in two experimental periods: 7 days (Groups I, I, and III) and 70 days (Groups IV, V and, VI). After pulpotomy, pulp remnant was covered with the following materials: Groups I and IV Enamel Matrix Derivative (Emdogain®); Groups II and V (negative control) Calcium hydroxide p.a.; and Groups III and VI (positive control) Zinc oxide and eugenol. At the established experimental periods, the animals were euthanized and the anatomic pieces were obtained and histologically processed. The microscopic evaluation was performed in a light microscope regarding the presence or absence of induced dentin barrier, severity of inflammation, presence or absence of bleeding, presence or absence of focal osteogenesis, presence or absence of pulp necrosis, presence of external root resorption and periodontal ligament thickness. Radiographic evaluation was performed considering the integrity of the lamina dura, presence of areas of periapical bone rarefaction, root resorption (internal and external) and dentin bridge formation. The results were analyzed statistically using Fisher´s exact test (&alpha;= 0.05). In the specimens presenting apical periodontitis, the areas of the lesions were determined and the groups were compared using the Kruskal-Wallis test followed by Dunn test (&alpha;= 0.05). The histopathologic findings in the 7-day period revealed that Group I presented a mild to moderated inflammatory infiltrate and intense vascular proliferation in the pulp tissue; Group II presented a mild inflammatory and an intact pulp tissue, while Group III presented a moderate to severe inflammatory infiltrate. In all groups, there was no dentin bridge formation and the periapical region had normal appearance. In the 70-day period, Groups IV and VI showed no dentin bridge formation and pulp tissue presented necrotic areas with inflammatory cells in the periapical region as well as bone and cemental resorption. On the other hand, in Group V, there was dentin bridge formation, absence of inflammatory process and absence of resorption of mineralized tissues. Regarding the radiographic findings, in the 7-day period, all specimens in Groups I, II e II present intact lamina dura, absence of periapical bone rarefaction, absence of root resorption (internal and external) and absence of dentin bridge formation. In the experimental 70-day period, Group IV showed discontinuity of the lamina dura and presence of periapical bone rarefaction in 100% of cases. Internal root resorption and dentin bridge formation were not observed, with external root resorption in 75% of cases. In Groups V and VI, absence of hard layer and presence of periapical bone rarefaction were observed in 25% and 50% of cases, respectively and external root resorption in 25% of cases. Presences of internal root resorption and dentin bridge formation were not observed in any group. Based on these results, it may be concluded that Enamel Matrix Derivative (Emdogain®) did not present satisfactory results when applied on the pulp tissue following pulpotomy.

No description available.