Spontaneous osteonecrosis of the jaws in the maxilla of mice on antiresorptive treatment: A novel ONJ mouse model

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The edentulous ridge expansion (ERE) technique an experimental study in the dog

Objective: To compare the healing and bony crest resorption at implants installed conventionally or applying an edentulous ridge expansion (ERE) technique in the maxilla.Material and methods: In six Labrador dogs, the first and second maxillary incisors were extracted bilaterally. In the left side of the maxilla (Test), the flaps were elevated and the buccal plate of the alveoli and septa was removed. After 3 months of healing, partial-thickness (split) flaps were dissected and the residual alveolar bone was exposed. In the right side of the maxilla, an implant was installed conventionally (Type IV; Control) while, in the left side, the ERE technique was adopted. Hence, an expansion of the buccal bony crest was obtained, and the implant was subsequently installed (Test). After 3 months of healing, biopsies were obtained and ground sections were prepared for histological analyses.Results: A buccal vertical resorption of the bony crest of 2.2 +/- 1.2 mm and 1.6 +/- 0.7 mm was found at the test and control sites, respectively. The difference, however, did not reach statistical significance. The coronal level of osseointegration at the buccal aspect was located at 3.1 +/- 1.0 mm and 2.2 +/- 0.7 mm from the implant shoulder at the test and control sites, respectively, the difference being statistically significant. The mean values of the mineralized bone-to-implant contact (MBIC%) ranged from 43% to 48% at the buccal and lingual sites. No differences reached statistical significance.Conclusions: Implants installed by applying an ERE technique may osseointegrate similarly to conventional implant installation. However, vertical and horizontal resorption of the displaced buccal bony wall occurred as well.

Antiplatelet drugs reduce the immunoinflammatory response in a rat model of periodontal disease

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Piezosurgery Applied to Implant Dentistry: Clinical and Biological Aspects

Piezosurgery is a new and modern technique of bone surgery in implantology. Selective cutting is possible for different ultrasonic frequencies acting only in hard tissues (mineralized), saving vital anatomical structures. With the piezoelectric osteotomy technique, receptor site preparation for implants, autogenous bone graft acquistition (particles and blocks), osteotomy for alveolar bone crest expansion, maxillary sinus lifting, and dental implant removal can be performed accurately and safely, providing excellent clinical and biological results, especially for osteocyte viability. The aim of this review was, through literature review, to present clinical applications of piezosurgery in implant dentistry and outline their advantages and disadvantages over conventional surgical systems. Moreover, this study addressed the biological aspects related to piezosurgery that differentiate it from those of bone tissue approaches. Overall, piezosurgery enables critical operations in simple and fully executable procedures; and effectively, areas that are difficult to access have less risk of soft tissue and neurovascular tissue damage via piezosurgery.

Effects of Locally Administered Tiludronic Acid on Experimental Periodontitis in Rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Doença periodontal em cães

Periodontal disease affects the periodontum which are tissues that support and protect the tooth and are composed by the gingiva, alveolar bone, cementum and periodontal ligament. Lesions in the periodontum have as main etiologic agent the presence of plaque or biofilm, which is formed in 24 hours and, basically, it consists of microorganisms surrounded by some bacteria rich matrix products and salivary glycoproteins. Gingivitis is the first clinical manifestation of periodontal disease and it is reversible if the etiologic agent (plaque) is removed. However, if it is not treated or controlled, it will lead to an irreversible periodontitis, and even evolve into alveolar bone, tissue destruction and, eventually, tooth loss

An unusual case of severe primary molar infraocclusion

Dentoalveolar ankylosis is described as the direct union between root cementum/dentin and alveolar bone. Its etiology is unknown, and conflicting opinions have been presented to explain it. Late detection of ankylosed primary teeth may cause serious problems to the occlusion and generally demands a more complex treatment approach. The purpose of this report is to present an unusual case of severe infraocclusion of the primary maxillary right second molar associated with a posterior crossbite in a 6-year-old child. The initial treatment option was tooth extraction, but the tooth resumed eruption spontaneously. After correction of the posterior crossbite and a 1-year follow-up, the tooth remained in occlusion and the permanent successor was developing without problems. From this unusual outcome, it may be concluded that further investigation of this anomaly of eruption is needed. (J Dent Child 2013;80(2):88-91)

Infra-oclusão de molares decíduos: diagnóstico e tratamento

Infraocclusion of deciduous molars is defined by total or partial periodontal ligament absence and characterized by the cementum or dentin anatomical fusion with alveolar bone. This study aims to report an ankylosis clinical case, the implications and treatments management options in the deciduos dentition.

Ertty System®: distalização segmentar

Introduction: Ertty System® is an intraoral system of biomechanical forces to move teeth anteroposteriorly. The application of forces on this system results in the distalization of the molar and all lateral segment in the side to be distalized, including premolars and canine, resulting in alveolar bone remodeling. This system is indicated to correct uni- or bilateral maxillary dental Class II malocclusion in permanent dentition both in children and adults. It is contraindicated in case of skeletal asymmetries, protrusion of maxillary and mandibular teeth, skeletal Class II and Class II subdivision malocclusions with mandibular midline deviation. This study describes Ertty System® and presents two clinical cases treated using this system. The two female patients presented with Class II malocclusion subdivision and maxillary midline deviation. Results: It was achieved correct alignment and leveling, Class I dental relation and correction of upper midline. Conclusion: The success and stability of results confirmed diagnosis and treatment adequacy.

Caracterização radiográfica ex vivo de biomateriais utilizados para regeneração óssea em mandíbulas de porcos

Introduction: The radiographic characteristics of a biomaterial, such as its density, may influence the evaluation of the results obtained following its clinical use. Objective: The aim of this study was to evaluate the radiographic density of biomaterials used as bone substitutes, inserted into dental sockets and bone defects in created in the jaws of pigs. The influence of a soft tissue simulator on the results was also evaluated. Material and method: Two and three-millimeter-deep bone defects were created in the pigs mandible and the right first molar extraction socket were used. Commercial samples of five biomaterials were tested: Hydroxyapatite, Lyophilized Bovine Bone, 45S5 bioglass (generic), PerioGlass and β-Tri-Calcium Phosphate, and compared to a positive (mandibular bone) and negative (empty alveolar bone defects) controls. Radiographic images were acquired with and without a 10 mm thick soft-tissue simulator. Result: The results for the extraction sockets showed no differences between the biomaterials and the negative control. For the bone defects, the depth of the defect density influenced the density, both in the negative control (p < 0.01) and biomaterials (p < 0.05) groups. The soft- tissue simulator did not alter the results. Conclusion: The type of the evaluated defect can interfere in the radiographic features presented by each biomaterial, while the simulation of soft tissues was not statistically significant.

Reabilitação total da maxila com enxerto intraoral: relato de caso

The early tooth loss and periodontal disease often leave inadequate bone volume for installation of osseointegrated implants. The autogenous bone graft is considered the gold standard for reconstruction of residual bone defects. Some surgical techniques can be performed, including extra or intraoral donor sites depending on the degree of bone loss, depending on surgical-prosthetic planning and general condition of the patient. The intraoral bone grafts offer a safe option to rebuilt bone volume in smaller rehabilitations, with low morbidity and minimal postoperative discomfort. Among the possible donor sites, the mandibular ramus and body, which offer predominantly cortical bone, and the chin area, which offers corticomedullary bone tissue, can be harvested. The graft will be suitable both in quantity and quality, preserving the capacity of osteogenesis, osteoinduction and osteoconduction, which differentiate autogenous grafts from other biomaterials. The aim of this study was to report a clinical case in which the mandibular ramus graft was used for total reconstruction of an edentulous maxilla, showing that even large areas can be reconstructed with grafts from intraoral origin. All the steps that allowed the complete reconstruction of the maxilla done by an intraoral donor area are listed in the text, culminating in an extremely satisfactory clinical result.

Use of salivary biomarkers for diagnosis of periodontal disease activity: a literature review

Periodontal disease is an infectious disease characterized by the connective tissue destruction and consequent alveolar bone loss in response to plaque accumulation on the tooth surface. The clinical diagnosis of periodontal disease is based both on clinical examination involving the evaluation of probing depth and radiographic examination of alveolar bone loss but these examinations are not enough to determine the activity of the disease process. For that reason, it has been proposed to seek predictive disease markers in an attempt to assess the disease activity and so, evaluate the efficacy of the periodontal disease treatment. The aim of this review is to present recent advances in the development of proteomic, genomics and microbial biomarkers and potential clinical applications. It was concluded that periodontal treatment based on assessing the levels of salivary biomarkers emerges as a promising method in near future and will become an integral part of the evaluation of periodontal health.

RANKL expression is differentially modulated by TLR2 and TLR4 signaling in fibroblasts and osteoblasts

Resident, non-immune cells express various pattern-recognition receptors and produce inflammatory cytokines in response to microbial antigens, during the innate immune response. Alveolar bone resorption is the hallmark of destructive periodontitis and it is caused by the host response to bacteria and their mediators present on the biofilm. The balance between the expression levels of receptor activator of nuclear factorkappa B ligand (RANKL) and osteoprotegerin (OPG) is pivotal for osteoclast differentiation and activity and has been implicated in the progression of bone loss in periodontitis. To assess the contribution of resident cells to the bone resorption mediated by innate immune signaling, we stimulated fibroblasts and osteoblastic cells with LPS from. Escherichia coli (TLR4 agonist), Porphyromonas gingivalis (TLR2 and -4 agonist), and interleukin-1 beta (as a control for cytokine signaling through Toll/IL-1receptor domain) in time-response experiments. Expression of RANKL and OPG mRNA was studied by RT-PCR, whereas the production of RANKL protein and the activation of p38 MAPK and NF-kB signaling pathways were analyzed by western blot. We used biochemical inhibitors to assess the relative contribution of p38 MAPK and NF-kB signaling to the expression of RANKL and OPG induced by TLR2, -4 and IL1β in these cells. Both p38 MAPK and NFkB pathways were activated by these stimuli in fibroblasts and osteoblasts, but the kinetics of this activation varied in each cell type and with the nature of the stimulation. E. coli LPS was a stronger inducer of RANKL mRNA in fibroblasts, whereas LPS from P. gingivalis downregulated RANKL mRNA in periodontal ligament cells but increased its expression in osteoblasts. IL-1β induced RANKL in both cell types and without a marked effect on OPG expression. p38 MAPK was more relevant than NF-kB for the expression of RANKL and OPG in these cell types.

Uso de um distrator ósseo dentoimplantossuportado, feito a partir de tornos expansores convencionais, na reabilitação oral

Osteodistraction is a clinical reality, available in the last decades for the resolution of large bone deficiencies, in cases that there are pre-existing, but misplaced implants and teeth. The aims of thearticle is to present a case report in which a new possibility for bone distraction, based on tooth-implant bone distractors, made from standard orthodontic expansion-screws, was used in an area where there was an extensive need of alveolar bone and aesthetical recovery, allied to teeth and dental implant misplacement. This technique presented good clinical results, associated to effective simplicity and low cost, becoming viable clinical solution for bone tissue augmentation and aesthetical optimization. In resume, it is possible to say that the suggested technique achieved its objectives, improving the hard and soft tissue profile, whilst allowing completion of oral rehabilitation.

Periodontal pathogens directly promote autoimmune experimental arthritis by inducing a TLR2- and IL-1-Driven Th17 response

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)