26 research outputs found
Combination of leukocyte and platelet–rich fibrin and demineralized bovine bone graft enhanced bone formation and healing after maxillary sinus augmentation: a randomized clinical trial
Background and objective: The resorption of alveolar ridge bone and maxillary sinus pneumatization are challenges to implant-supported prosthetic rehabilitation. Bone regeneration using bone substitutes and growth factors are alternatives for maxillary sinus augmentation (MSA). Therefore, we sought to evaluate the effects of the association between leukocyte and platelet–rich fibrin (L-PRF) and deproteinized bovine bone mineral (DBBM) in MSA procedures. Materials and methods: Thirty-six maxillary sinuses from 24 individuals were included in this randomized clinical trial. The maxillary sinuses were randomly grafted with LPRF and DBBM (test group) or grafted only with DBBM (positive control). Dental implants were installed in the test group following two periods of evaluation: after 4 (DBBM+LPRF4) and 8 (DBBM+LPFR8) months of sinus graft healing, while the control group received implants only after 8 months. Cone beam computed tomography (CBCT) was taken 1 week after surgery (T1) and before implant placement (T2). Bone samples were collected during implant placement for histomorphometric and immunohistochemical (IHC) analysis. The primary implant stability was assessed by resonance frequency analysis. Results: CBCT analysis demonstrated a significant decrease in bone volume from T1 to T2 in all groups without differences among them. Histologically, the test group showed significantly increase in bone neoformation in both periods of evaluation (LPRF+DBBM4: 44.70±14.01%; LPRF+DBBM8: 46.56±12.25%) compared to the control group (32.34±9.49%). The control group showed the highest percentage of residual graft. IHC analysis showed increased staining intensity of osteocalcin (OCN), vascular endothelial growth factor (VEGF), and runt related transcription factor 2 (RUNX-2) in LPRF+DBBM4 group, and osteopontin (OPN) in the L-PRF+DBBM8. Primary implant stability was successfully achieved (above 60 in implant stability quotient) in all the evaluated groups. Conclusion: Combination of L-PRF and DBBM increased and accelerated new bone formation allowing early implant placement probably due to the higher protein expression of RUNX2, VEGF, OCN, and OPN. These data suggest that the use of L-PRF might be an interesting alternative to use in combination with DBBM for augment the maxillary sinuses allowing the installation of appropriate length implants in shorter period of time. Clinical relevance: This study showed improvement in bone neoformation and accelerated healing when associating L-PRF and DBBM for maxillary sinus augmentation procedures. Trial registration: This study was registered before participant recruitment in Brazilian Registry of Clinical Trials (ReBEC - RBR-95m73t).</p
The smear layer created by scaling and root planing is physiologically eliminated in a biphasic process
Avaliação in vitro do efeito da dieta ácida e da escovação na permeabilidade da dentina radicular
O objetivo deste trabalho in vitro foi quantificar as alterações na permeabilidade da dentina radicular após exposição a diferentes ácidos da dieta, assim como avaliar o efeito da escovação sem e com dentifrício subseqüente à aplicação dos ácidos. A dentina radicular de terceiros molares extraídos foi exposta com a utilização de fresa em alta rotação. As coroas foram seccionadas acima da junção amelocementária e o tecido pulpar foi removido. Após o preparo, cada amostra foi conectada a um sistema de pressão para que a permeabilidade da dentina radicular pudesse ser mensurada após as seguintes etapas seqüenciais: I) aplicação do EDTA por 3 minutos para obtenção da permeabilidade máxima II) raspagem radicular para formação de uma nova smear layer; III) exposição às diferentes substâncias ácidas (vinagre, coca-cola, suco de limão, vinho branco, suco de laranja); IV) escovação sem dentifrício por 3 minutos; V) escovação com dentifrício por 3 minutos. Os resultados mostraram que todas as substâncias ácidas aumentaram significativamente a permeabilidade dentinária após a raspagem radicular. Os sucos de limão e laranja provocaram maior aumento no valor da permeabilidade da dentina radicular em comparação com as demais substâncias. A escovação subseqüente à exposição ácida reduziu a permeabilidade dentinária e a associação com o dentifrício provocou uma redução adicional na permeabilidade dentinária. Pôde-se concluir que ácidos da dieta aumentam a permeabilidade da dentina radicular e que a escovação sem e com dentifrício promove uma redução na permeabilidade da dentina radicular após exposição ácida da dentina.The purpose of this in vitro study was to quantitate the alterations of human root dentin permeability after exposure to different dietary acids and to evaluate the effect of toothbrushing with or without toothpaste after acid application. The root dentin from extracted human third molars was exposed by means of a high speed bur. Crowns were sectioned above cementoenamel junction and the pulp was removed. After preparation, each sample was connected to the hydraulic pressure apparatus to measure the permeability of root dentin after the following sequencial steps: I) treatment with EDTA for 3 minutes to obtain the maximum permeability; II) root planing to create a new smear layer; III) exposure to different acidic substances for 5 minutes (vinegar; cola drink, lemon juice; white wine and orange juice); IV) toothbrushing without toothpaste for 3 minutes; V) toothbrushing with toothpaste for 3 minutes. Results demonstrated that all acidic substances statistically increased dentin permeability after root planing. Lemon and orange juices showed higher values for dentin permeability when compared to the others substances. Brushing procedures after acid exposure reduced dentin permeability and the application of toothpaste caused an additional reduction in dentin permeability. Thus, dietary acids ultimately increase root dentin permeabilility and toothbrushing with or without toothpaste reduce root dentin permeability after acid exposure.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Efeito do condicionamento radicular na reparação periodontal de defeitos tipo deiscência: Estudo experimental em cães
O objetivo do presente estudo foi avaliar clinicamente e histologicamente o efeito do condicionamento químico da superfície radicular com ácido cítrico (AC), tetraciclina hidroclorada (TTC HCl), e ácido etilenodiaminotetracético (EDTA) na reparação periodontal de defeitos ósseos tipo deiscência em cães. Defeitos tipo deiscência com 5 × 3 mm foram criados cirurgicamente na face vestibular das raízes mesiais dos primeiros molares, segundos e terceiros pré-molares superiores de sete cães. Assim, em cada animal foram criados seis defeitos que foram posteriormente submetidos ao acúmulo de placa por 45 dias. Após este período, foi realizado o exame clínico (baseline) dos dentes envolvidos no experimento e, em seguida, um retalho de espessura total foi rebatido. As superfícies radiculares foram raspadas e os defeitos receberam um dos seguintes tratamentos: I) irrigação com solução salina estéril (controle); II) ácido cítrico (25%, 3 min); III) EDTA (24%, 3 min); IV) tetraciclina hidroclorada (50 mg/ml, 3 min); V) ácido cítrico (3 min) + tetraciclina hidroclorada (3 min); VI) tetraciclina hidroclorada (3 min) + ácido cítrico (3 min). Após três meses de cicatrização, foi realizado o exame clínico final e os animas foram sacrificados para obtenção dos blocos contendo dente e tecidos periodontais adjacentes para análise histológica. Clinicamente, foi verificado que houve uma redução significativa da profundidade de sondagem e um significativo ganho de inserção clínica em todos os grupos após o tratamento dos defeitos (p 0.05). Em relação aos parâmetros histológicos avaliados, também não foi constatado uma diferença significativa entre os grupos (p > 0.05). A migração epitelial assim como a formação de novo cemento e osso alveolar foram semelhantes em...The purpose of this study was to clinically and histologically evaluate the effect of root surface conditioning with citric acid (CA), tetracycline hydrochloride (TTC HCl), and ethylenediaminetetraacetic acid (EDTA) on the periodontal repair of dehiscence-type defects in dogs. Dehiscence defects measuring 5 × 3 mm were surgically created on the buccal aspect of mesial roots of the maxillary first molars and second and third pre-molars of seven mongrel dogs. For each animal, a total of six defects were created and exposed to plaque accumulation for 45 days. After this period, clinical evaluation (baseline) of all teeth was performed and a full thickness buccal flap raised. The root surfaces were scaled and the defects were randomly assigned to one of the following treatments: I) irrigation with sterile saline solution; II) citric acid (25%, 3 min); III) EDTA (24%, 3 min); IV) tetracycline hydrochloride (50 mg/ml, 3 min); V) citric acid (3 min) and tetracycline hydrochloride (3 min); VI) tetracycline hydrochloride (3 min) and citric acid (3 min). After 3 months of healing, the clinical parameters (final) were evaluated and the animals were sacrificed to obtain block sections of the teeth and surrounding tissues for histological analyses. Clinically, all treatments yielded significant improvements in terms of probing depth decrease and attachment clinical level gain compared to baseline values (p 0.05). Epithelial apical migration as well as newly formed cementum and alveolar bone were similar in all treatment groups. No statistically significant differences were found among the groups in relation to the histological parameters evaluated (p > 0.05). Within the limits of this study, it can be concluded that chemical root surface conditioning combined with flap surgery and root scaling did not have any... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Prevalence and possible risk factors of peri-implantitis: a concept review
The purpose of this review is to estimate the prevalence of peri-implantitis, as well as to determine possible risk factors associated with its development in patients treated with oral implants. Although implant therapy has been identified as a successful and predictable treatment for partially and fully edentulous patients, complications and failures can occur. Peri-implantitis is considered a biologic complication that results in bone loss around implants and may lead to implant treatment failure. A great variation has been observed in the literature regarding the prevalence of peri-implantitis according to the diagnostic criteria used to define peri-implantitis. The prevalence ranges from 4.7 to 43% at implant level, and from 8.9 to > 56% at patient level. Many risk factors that may lead to the establishment and progression of peri-implantitis have been suggested. There is strong evidence that presence and history of periodontitis are potential risk factors for peri-implantitis. Cigarette smoking has not yet been conclusively established as a risk factor for peri-implantitis, although extra care should be taken with dental implant in smokers. Other risk factors, such as diabetes, genetic traits, implant surface roughness and presence of keratinized mucosa still require further investigation. Peri-implantitis is not an uncommon complication following implant therapy. A higher prevalence of peri-implantitis has been identified for patients with presence or history of periodontal disease and for smokers. Until now, a true risk factor for peri-implantitis has not been established. Supportive maintenance program is essential for the long-term success of treatments with oral implants. The knowledge of the real impact of peri-implantitis on the outcome of treatments with oral implants as well as the identification of risk factors associated to this inflammatory condition are essential for the development of supportive maintenance programs and the establishment of prevention protocols
In vitro evaluation of the effect of dietary acids and toothbrushing on human root dentin permeability
OBJECTIVES: The purpose of this in vitro study was to quantify the alterations in human root dentin permeability after exposure to dietary acids and to evaluate the effect of toothbrushing after acid application. METHOD AND MATERIALS: Extracted human third molars had their crowns sectioned above the CEJ, pulp tissue removed, and cervical root dentin exposed using a high-speed bur (approximately 1 mm in depth of substance loss). From each root fragment, one specimen was prepared. A total of 25 specimens were used and distributed randomly into five groups. The specimens were attached to a hydraulic pressure apparatus to evaluate the alterations of root dentin permeability after exposure to different acids. Dentin permeability was measured after the following sequential steps: (1) treatment with EDTA for 3 minutes to obtain the maximum permeability; (2) root planing to create a smear layer; (3) exposure to different acidic substances for 5 minutes (vinegar, cola drink, lemon juice, white wine, and orange juice); and (4) brushing for 3 minutes. RESULTS: All acidic substances increased dentin permeability after root planing. Lemon juice produced higher values for permeability when compared to the other substances (P = .009); moreover, orange juice showed similar results (P < .02) except when compared to vinegar (P = .12). Brushing right after acid exposure significantly reduced dentin permeability except in the vinegar group (P = .07). CONCLUSION: Under the experimental conditions, dietary acids increased root dentin permeability, and immediate brushing reduced permeability levels
Effect of saliva substitutes in combination with fluorides on remineralization of subsurface dentin lesions
Purpose Saliva substitutes are prescribed to patients suffering from radiation-induced hyposalivation to alleviate oral complaints; however, some available products have shown to demineralize dentin. The purpose of this in vitro study was to evaluate the effects of two saliva substitutes in combination or not with fluoridation on remineralization of bovine dentin subsurface lesions.Materials and methods Dentin specimens were demineralized, and stored in either mineral water (control; volvic, danone), Glandosane (cell pharm), or modified Saliva natura (SN, Medac) for 5 weeks (37 degrees C). The following treatments were applied twice daily (n=12/group): (1) no treatment; (2) immersion in pure Elmex sensitive mouthrinse (250 ppm F(-); 10 min; Gaba); (3) brushing with Duraphat toothpaste (5,000 ppm F(-); Colgate)/storage solution slurry (5 s; ratio 1: 3); (4) combination of treatments 2 and 3. Differences in mineral parameters before and after storage/treatment were microradiographically evaluated.Results After 5 weeks, Glandosane-induced a significant demineralization of dentin specimens. The mineral loss of specimens stored in Glandosane was significantly higher compared to all other solutions (p<0.05), and this side effect was inhibited by the fluoride products (p<0.05; ANOVA, Tukey). Modified Saliva natura enabled considerable remineralization, and this was significantly increased by daily application of both fluoride products (p<0.05).Conclusions Modified Saliva natura has remineralizing properties, while Glandosane is a demineralizing saliva substitute that should only be used with frequently applied fluorides in dentate patients.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Saliva substitutes in combination with high-fluoride gel
Objective This study aimed to determine whether the application of a high-fluoride gel could increase the remineralization of subsurface dentin lesions stored in saliva substitutes. Materials and methods Demineralized bovine dentin specimens were stored in mineral water (W), Glandosane (G), or modified Saliva natura (SN). Different treatments were applied twice daily: no treatment, Elmex sensitive mouth rinse (E), ProSchmelz gel (P), Duraphat toothpaste (D), ED, PD, and EPD. Differences in mineral loss were evaluated by transversal microradiography after 2 and 5 weeks. Results The treatments with E, D, and ED inhibited the mineral loss induced by G and enabled some mineral gain. ProSchmelz was not able to inhibit the demineralizing effect of G. This high-fluoride gel induced an erosive mineral loss in combination with G. The use of ProSchmelz in combination or not with other fluoride products did not increase remineralization of specimens stored in SN or W (p>0.05). ProSchmelz resulted in an erosion of the specimens stored in W and revealed a lower mineralized surface layer of specimens stored in SN. Conclusion Topical application of high-fluoride gel reduced the mineral loss induced by G but resulted in an erosion of specimens’ surface. In addition, ProSchmelz did not demonstrate beneficial effects in combination with SN on subsurface dentin lesion remineralization. Clinical relevance Within the limitations of an in vitro study, it was concluded that the application of a high-fluoride gel did not promote additional effects on remineralization of subsurface dentin lesions in combination with saliva substitutes when compared to products with lower fluoride concentration.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
The influence of vinegars on exposure of dentinal tubules: a SEM evaluation.
Dentin hypersensitivity is a common painful condition observed in clinics. Dietary habits have been much associated with its development and persistence during and following periodontal treatment. The aim of this in vitro study was to evaluate the influence of vinegars on the removal of smear layer and exposure of dentinal tubules. Extracted human teeth were submitted to manual scaling with Gracey curettes in order to remove the cementum as well as to form a smear layer. Dentin samples with 3 mm(2) were obtained and distributed into six experimental groups: one control and five types of vinegars (alcohol, apple, rice, white wine and balsamic). Each group included two methods of vinegar application: topical and friction. After routine preparation for SEM analysis, photomicrographs were assessed by a calibrated and blind examiner using an appropriate index system. Kruskal-Wallis test indicated a significant influence of vinegars on smear layer removal. There was a statistically significant difference between groups treated with apple, white and rice vinegars and the control group (p < 0.05). Nevertheless, Mann-Whitney test indicated that removal of smear layer did not vary with the method of application (topical versus friction) for any of the tested substances. We can conclude that the contact of vinegar may remove smear layer and expose dentinal tubules, regardless of the type of application. However, balsamic vinegar was associated with less removal of smear layer after both methods of application
The smear layer created by scaling and root planing is physiologically eliminated in a biphasic process
Mechanical instrumentation of the root surface causes the formation of a smear layer, which is a physical barrier that can affect periodontal regeneration. Although different procedures have been proposed to remove the smear layer, there is no information concerning how long the smear layer persists on root surfaces after instrumentation in vivo. This study assessed the presence of the smear layer on root surfaces over a 28-day period after subgingival instrumentation with hand instruments. Fifty human teeth that were referred for extraction because of advanced periodontal disease were scaled and root planed (SRP) by a single experienced operator. Ten teeth were randomly assigned to be extracted 7, 14, 21, and 28 days after SRP. Another 10 teeth were extracted immediately after instrumentation (Day 0, control group). The subgingival area of the instrumented roots was evaluated with scanning electron microscopy. Representative photomicrographs were assessed by a blinded and calibrated examiner according to a scoring system. A rapid and significant (p < 0.05, Z test) initial reduction in the amount of smear layer was observed at 7 days, and a further significant (p < 0.05) decrease was observed 28 days after SRP. Interestingly, even 28 days after SRP, the smear layer was still present on root surfaces. This study showed that the physiological elimination of the smear layer occurred in a biphasic manner: a rapid initial reduction was observed 7 days after instrumentation, which was followed by a slow process leading to a significant decrease 28 days after instrumentation.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq