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This study investigated the influence of implant surface on osseointegration around titanium implants inserted in the tibiae of rabbits administered with nicotine.Thirty-two (32) New Zealand rabbits were included in the study. After anesthesia, the tibia surface was exposed and 2 screw-shaped commercially available pure titanium implants 7.0 mm in length and 3.75 mm in diameter were placed bilaterally. A total of 128 implants were inserted: 64 blasted with Al2O3 particles (Group 1) and 64 with a machined surface finish (Group 2). The animals were randomly assigned to 1 of 4 treatment subgroups, and daily subcutaneous injections of nicotine were administered: A) saline solution; B) 0.37 mg/kg; C) 0.57 mg/kg; and D) 0.93 mg/kg. In order to label regenerated bone, a 2% calcein green solution was administered by intramuscular injection at 0, 7, and 15 days after implant insertion. After 42 days, the animals were sacrificed and undecalcified sections were prepared. The degree of bone contact with the implant surface, the bone area, and the intensity of bone labeling were measured into the limits of the implant threads.Statistical analysis (2-way ANOVA) revealed no significant difference regarding the effect of nicotine on bone healing around the implants (P0.05). However, a significant influence of the implant surface on the degree of bone-to-implant contact was detected in groups C (30.13 +/- 4.97 and 37.85 +/- 8.85, for machined and Al2O3-blasted surfaces, respectively) and D (27.79 +/- 3.93 and 33.13 +/- 8.87, for machined and Al2O3-blasted surfaces, respectively) (P0.05).Although nicotine administration may not statistically influence bone healing around titanium implants, implant surface design may enhance osseointegration after nicotine administration.

Background and Objective The immune and infectious alterations occurring in periodontitis have been shown to alter the development and severity of cardiovascular disease. One of these relationships is the translocation of oral bacteria to atheroma plaques, thereby promoting plaque development. Thus, the aim of this study was to assess, by 16s cloning and sequencing, the microbial diversity of the subgingival environment and atheroma plaques of patients concomitantly suffering from periodontitis and obstructive coronary artery atherosclerosis (OCAA). Methods Subgingival biofilm and coronary balloons used in percutaneous transluminal coronary angioplasty were collected from 18 subjects presenting with generalized moderate to severe periodontitis and OCAA. DNA was extracted and the gene 16S was amplified, cloned and sequenced. Results Significant differences in microbial diversity were observed between both environments. While subgingival samples mostly contained the phylum Firmicutes, in coronary balloons, Proteobacteria (p

This study evaluated, by histometric analysis, the wound healing process of bone around implants placed into extraction sockets with or without the concurrent application of a combination of platelet-derived growth factor (PDGF) and insulin-like growth factor (IGF-1). Mandibular premolars were removed, and 32 implants were inserted in eight dogs. Before insertion, two implants received a single application of 5 micrograms/mL of PDGF and IGF-1 delivered in 0.10 mL of 4% methylcellulose gel or 0.10 mL of 4% methylcellulose gel only as a control. To label regenerated bone, a 2% calcein green solution was administered by intramuscular injection at 0, 7, 15, 30, 45, 60, and 75 days after implant insertion. Three, 8, and 12 weeks after implant insertion, undecalcified sections were obtained, and the degree of bone contact with the implant surface, the bone area, and the intensity of bone labeling were measured into the limits of the threads of the implant. Greater extension of bone/implant contact (paired t test, P < .05) was observed in test (22.4% +/- 13.7%) than in control (17.2% +/- 13.6%) implants at 3 weeks. One-way ANOVA revealed a higher intensity of bone labeling (P < .05) at 3 weeks than at 12 weeks (127.8 +/- 42.59 and 56.7 +/- 26.34, gray scale values) for test implants. Within the limits of the present study, it was concluded that the combination of PDGF/IGF-I actively took part in the initial phase of bone repair.

Bone regeneration was evaluated around immediate implants partially in contact with bone, with or without the concurrent application of a combination of platelet-derived growth factor (PDGF) and insulin-like growth factor (IGF-1). Mandibular premolars were removed, and the implant osteotomies were prepared; a uniform circumferential gap was prepared 1.25 mm beyond the width of the implant bed in the coronal half. Twelve implants (8.5 x 3.75 mm) were inserted in six dogs. Before insertion, an implant received a single application of 5 micrograms/mL of PDGF and IGF-1 delivered in 0.10 mL of 4% methylcellulose gel or 0.10 mL of 4% methylcellulose gel only as a control. To label regenerated bone, a 2% calcein green solution was administered by intramuscular injection at 0, 7, 15, 30, and 45 days after implant insertion Three and 8 weeks after implant insertion undecalcified sections were obtained, and the degree of bone to implant contact, the bone area, and the intensity of bone labeling were measured into the limits of the eight most coronal threads of the implant (four threads on each side of each implant). The results showed a greater extension of bone-to-implant contact, a larger percentage of bone area, and greater intensity of bone labeling for test versus control implants (P < .01). Within the limits of the present study, it was concluded that the combination of PDGF/IGF-1 might be an alternative for enhancing bone healing around implants partially in contact with bone.

The purpose of this study was to clinically evaluate an absorbable collagen membrane (Bio-Gide) and a nonabsorbable polytetrafluoroethylene membrane (PTFE), associated or not with bone grafts, for the treatment of ligature-induced peri-implantitis defects in dogs. The bilateral mandibular premolars were removed from 5 2-year-old mongrel dogs. After 3 months of healing, 3 titanium implants were placed on each side of the mandible. Experimental peri-implantitis was induced after abutment connection. Ligatures and abutments were removed after 1 month and the bone defects were randomly assigned to one of the following treatments: DB: debridement alone; GBR+BG-I: debridement plus PTFE membrane associated with mineralized bone graft (Bio-Oss); GBR+BG-II: debridement plus collagen membrane (Bio-Gide) associated with mineralized bone graft; GBR-I: debridement plus PTFE membrane; GBR-II: debridement plus collagen membrane; BG: debridement plus mineralized bone graft. The peri-implant bone defects were measured before and 5 months after treatment. Results showed the greatest percentage of vertical bone fill for GBR+BG-II (27.77+/-14.07) followed by GBR-II (21.78+/-16.19), BG (21.26+/-6.87), GBR+BG-I (19.57+/-13.36), GBR-I (18.86+/-10.63) and DB (14.03+/-5.6). However, the values were not statistically significant (ANOVA, contrast F test, P=0.612). Within the limits of the present investigation, it can be concluded that no difference was detected among treatments.

The purpose of this study was to evaluate, by histometric analysis, re-osseointegration following treatment of ligature-induced peri-implantitis in dogs. Five dogs were used in this study. Their mandibular premolars (P2, P3 and P4) were first removed. After 3 additional months of healing, two titanium implants were placed on each side of the mandible. After 3 months, the abutment connection was performed and experimental peri-implantitis was induced by placing cotton ligatures in a submarginal position. Ligatures and abutments were removed after one month and the peri-implant bone defects were randomly assigned to one of the treatments : debridement, debridement plus guided-bone regeneration, debridement plus mineralized-bone graft, and debridement plus guided-bone regeneration associated with mineralized-bone graft. Five months post-treatment, the degree of bone contact with the implant surface and the bone area within the threads were measured in 12 threads, the 6 most coronal at each side of each implant. One-way analysis of variance did not reveal statistically significant differences between the treatment modalities (p > 0.05). Within the limits of the present study, it can be concluded that there is a limited possibility of reosseointegration around implant surfaces previously exposed by ligature-induced peri-implantitis. (J. Oral Sci. 42, 163-168, 2000)

The goal of this investigation was to compare, histologically and histometrically, the healing process of dehiscence-type defects treated by guided tissue regeneration (GTR) with bioabsorbable polylactic acid (PLA) membranes and non-resorbable expanded polytetrafluoroethylene (ePTF) membranes.Six mongrel dogs were used. Buccal osseous dehiscences were surgically created on the distal roots of the mandibular third and fourth premolars. The defects were exposed to plaque accumulation for 3 months. After this period, the defects were randomly assigned to one of the treatments: GTR with bioabsorbable membrane (PLA), GTR with non-resorbable membrane (ePTFE), open flap debridement (OFD), and non-treated control (NTC). After 3 months of healing, the dogs were sacrificed and the blocks were processed. The histometric parameters evaluated included: gingival recession, epithelial length, connective tissue adaptation, new cementum, and new bone area.A superior length of new cementum was observed in the sites treated by GTR, regardless of the type of barrier used, in comparison with OFD (P0.05). No statistically significant differences were found between PLA and ePTFE in any of the parameters with the exception of bone area. PLA presented a greater bone area when compared to ePTFE, OFD, and NTC (P0.05).Within the limits of this study, it can be concluded that both barriers are equally effective for new cementum formation. The bioabsorbable membrane may provide a greater bone area than the non-resorbable membrane.

The goal of this investigation was to histologically and histometrically evaluate the healing process of gingival recessions treated by guided tissue regeneration with bioabsorbable polylactic acid membranes (GTR group) and to compare it to that obtained with coronally positioned flaps (CPF group).Gingival recessions were surgically created on the buccal aspect of the upper cuspids of 5 mongrel dogs. The defects (5x7 mm) were exposed to plaque accumulation for 3 months. The contralateral defects were then randomly assigned to each group. After 3 months of healing, the dogs were sacrificed and the blocks were processed. The histometric parameters evaluated included length of sulcular and junctional epithelium, connective tissue adaptation, new cementum, new bone, and defect coverage.The extension of the epithelium was 1.9 +/- 0.8 mm for the GTR-group and 3.0 +/- 0.9 mm for the CPF-group (P = 0.16). The connective tissue adaptation was 0.1 +/- 0.1 and 0.8 +/- 0.5 mm in the GTR group and CPF group, respectively (P = 0.051). The new cementum was 3.8 +/- 1.5 mm and 2.4 +/- 0.3 mm in the GTR group and CPF group, respectively (P= 0.16). Bone formation was 1.1 +/- 0.5 mm in the GTR group and 1.4 +/- 0.2 mm in the CPF group (P = 0.53). Histologically, the defect coverage observed was similar, 90.5% and 91.9% for the GTR group and the CPF group, respectively. No statistical differences in any of the parameters could be detected.Within the limits of this study, it can be concluded that both procedures resulted in a favorable healing response with no significant difference between the treatments.

We carried out a clinical evaluation of the hard tissue fill following treatment of ligature-induced peri-implantitis in dogs. Four dogs were used and their mandibular premolars (P2, P3 and P4) were removed. After 3 months of healing, two titanium implants were placed on each side of the mandible. After 3 months, the abutment connection was performed, and experimental peri-implantitis was induced by placement of cotton ligatures in a submarginal position. The ligatures and abutments were removed after one month, and the peri-implant bone defects were assigned randomly to one of the treatments: debridement (control), debridement plus guided bone regeneration (GBR), debridement plus mineralized bone graft (BG), and debridement plus guided bone regeneration associated with a mineralized bone graft (GBR + BG). Clinical measurements of the peri-implant bone defects before and 5 months after treatment revealed no statistically significant differences between the defects treated by GBR, BG and GBR + BG. These 3 treatment methods provided more hard tissue fill than debridement alone (p < 0.05). Thus, it can be concluded that GBR, BG or a combination of the two techniques can enhance the hard tissue fill in defects caused by peri-implantitis in dogs.

The purpose of this study was to evaluate the effects of calcitonin administration on bone healing, following titanium implant insertion. Thirty adult New Zealand rabbits received one implant in each femur. Fifteen animals were randomized to provide test (calcitonin) and control (saline solution) groups. The animals were sacrificed 7, 14, 21, 28 and 42 days after the surgical procedure. The analyzed parameters were new endosteal/periosteal bone length, new endosteal/periosteal bone area and total cortical length. Considering treatment, histometric measurements showed significant differences (p

The objective of this study was to evaluate the effect of non-surgical periodontal therapy in VSC formation and its relationship with periodontal disease severity. Twenty-five periodontal patients without treatment and a control group with 10 subjects were selected. The patients were classified according to their periodontal diagnosis based on clinical attachment level (CAL): marginal gingivitis (MG), slight periodontitis-CAL = 3 mm (P1), moderate periodontitis-CAL = 5 mm (P2), severe periodontitis-CAL = 7 mm (P3) and terminal periodontitis-CAL > 10 mm (P4). At baseline, all patients received oral hygiene instructions and scaling/root planning. The periodontal parameters: plaque index, gingival index, probing depth and clinical attachment level were evaluated in two experimental periods (T1 = Baseline and T2 = 3 months recall). The Halimeter® was used to detect VSC formation in the same periods. The results after three months showed that VSC formation, probing depth and clinical attachment level decreased similarly in groups MG and P1 (P

The presence of furcation lesions is associated with bone resorption and lack of insertion in the inter-radicular space, and is a condition that considerably increases the risk of dental loss, particularly in the absence of adequate treatment. In this context, the object of some of the therapies is to keep teeth with furcation lesions that are important to dental planning, to re-establish an anatomy that enables the patient to remove dental biofilm from the compromised area. However, the long term maintenance and treatment of molars with Class III furcation lesions continues to be a challenge to dentists during periodontal therapy, since the anatomy of the inter-radicular region makes it difficult for both professionals and patients to gain access to perform adequate and efficient control of dental biofilm. The impossibility of obtaining appropriate decontamination of the area involved during the root scraping process, including by means of surgical access, demands thatdentists have adequate knowledge to determine the correct therapeutic approach during the treatment of teeth with advance inter-radicularbone loss. The aim of the present study was to discuss the treatments available for Class III furcation lesions and relate clinical procedures that could be performed for the treatment of this type of defect.

The present investigation studies the changes that occur in periodontal supporting tissues of lower canine and premolar of marmosets (Callithrix jacchus), due to experimental modification of occlusal relationships in the region of the molar. For our purposes an extracoronal arch wire of 0.7 mm diameter was fixed into occlusal perforations of the upper third premolar and first molar, on both sides. Eight male marmosets weighing from 250 to 350 grams were used. After each experimental time interval of 7, 14, 21 and 28 days two animals were sacrificed. The results clearly showed areas of tension with stretched periodontal fibers in the distal region of the canine and areas of pressure with osseous and radicular resorption in the mesial region of the first premolar. The tissue changes may be considered to result from transmission of abnormal forces through the proximal contacts of teeth associated with displacements and minor modifications in their occlusal relationships. Similar changes may occur in a tooth distant from the teeth exposed to primary excessive occlusal forces.

The systemic administration of steroid hormone (0.400 mg of Dexamethasone every 2 days), during a 28-day period in marmosets (Callithrix jacchus) produced modifications in the evolution of the experimental periodontal traumatism. The observed changes were osteoporosis and reduction of the periodontal fibers in quantity as well as a reduction of repair process, when compared to the control group that only received the action of the trauma from occlusion.

A terapia com laser em baixa intensidade, conhecida como Low-intensity laser therapy (LILT), tem sido alvo de pesquisas que buscam esclarecer os mecanismos pelos quais o laser age na cicatrização de feridas. Este processo é dependente da transmissão de sinais entre epitélio e conjuntivo, os quais influenciam a proliferação e a migração celular, onde participam fatores de crescimento. O objetivo desta pesquisa foi verificar os efeitos da radiação com lasers vermelho e infravermelho em baixa intensidade na produção de fatores de crescimento por fibroblastos in vitro. Foi obtida uma cultura primária de fibroblastos gengivais humanos (linhagem FGH). As células foram cultivadas em placas de 96 poços (5 x 103 células /poço), em estado de quiescência (meio de cultura suplementado com 1% de soro fetal bovino) e irradiadas com lasers de diodo (AlGaAs - 660nm, e AlGaInP - 780nm). O laser em modo contínuo, foi aplicado em contato e na forma pontual. A potência utilizada foi de 40mW numa área de 0,042cm2 e com densidades de energia de 2, 3, 4, 5 e 6J/cm² com respectivos tempos de aplicação de 2, 3, 4, 5 e 6s. As culturas foram irradiadas duas vezes com 6h de intervalo. Os grupos controle positivo e negativo foram cultivados com 10% e 1% de soro fetal bovino, respectivamente e não receberam irradiação. A produção do fator de crescimento de queratinócitos (KGF) e do fator de crescimento de fibroblastos básico (bFGF) foi analisada e quantificada por ensaio imunoenzimático (método ELISA) no meio condicionado pelas células. Os dados foram comparados estatisticamente pela análise de variância e teste de Kruskal-Wallis complementados pelos testes de Tukey e Dunn, respectivamente (p

A utilização de fatores de crescimento no tratamento periodontal tem sido amplamente estudada. No entanto, sua aplicabilidade no tratamento de seres humanos ainda não foi estabelecida. Os objetivos deste trabalho foram determinar os efeitos da aplicação de PDGF-BB, IGF-1, TGF-ß1 e sua combinação na proliferação de células cultivadas originadas do ligamento periodontal de humano (células FL2). Além disso, analisou-se a adesão dessas células a fragmentos radiculares periodontalmente comprometidos tratados previamente ou não por associação de ácido cítrico e tetraciclina após a raspagem. Para tanto, foi estabelecida cultura primária de fibroblastos obtidos de 3º molares retidos e/ou impactados extraídos de pacientes saudáveis. Para analisar a taxa de proliferação celular, foram plaqueadas 72 placas de Petri contendo inicialmente 103 células aleatoriamente divididas em 4 grupos que receberam a adição de PDGF-BB (grupo 1), TGF-ß1 (grupo 2), IGF-1 (grupo 3) ou de sua combinação (grupo 4) ao meio de cultura e 2 grupos controle (sem adição de fatores de crescimento) e contadas em triplicatas após 1, 3, 5 e 7 dias. Paralelamente, foram obtidos 30 fragmentos de dentes extraídos de 14 pacientes com perda de inserção à sondagem > 6 mm aleatoriamente distribuídos em 10 grupos de acordo com o tratamento: raspagem (grupo 1), raspagem e aplicação dos fatores de crescimento isolados ou em combinação (grupos 2-5), raspagem e condicionamento ácido (grupo 6) ou raspagem, condicionamento ácido e aplicação dos fatores de crescimento isolados ou em combinação (grupos 7-10). Os resultados obtidos foram estatisticamente avaliados pelo teste ANOVA e por métodos descritivos. Os resultados demonstraram que o TGF-ß1 apresentou os melhores efeitos na proliferação de células do ligamento periodontal em cultura, enquanto que na adesão das células aos fragmentos a combinação dos três fatores apresentou resultados mais favoráveis, com diferenças estatisticamente significantes (p 6 mm and were randomly distributed among 10 treatment groups: scaling (group 1), scaling and growth factor application (groups 2-5), scaling and acid treatment (group 6) and scaling and acid treatment followed by growth factor application (groups 7-10). The data were statistically evaluated by ANOVA and descriptive methods. The results obtained have demonstrated that TGF-ß1 provided the more pronounced effects over cultured periodontal ligament fibroblasts proliferation while the combination of growth factors presented the most significant results over the its adhesion to periodontally compromised tooth fragments previously treated by scaling and citric acid associated to tetracycline conditioning for 3 minutes. These results were statistically different from the non-conditioned treatment groups (p