Enhanced bone apposition to Brazilian microrough titanium surfaces

It has recently been reported that machined and microrough (micro) Brazilian titanium (Ti) implants have good production standards. The aim of this study was to evaluate in vivo bone formation around 2 different implant surfaces placed in dog's mandible. Thirty-two screw-typed Ti implants were used in this study. Mandibular premolars were extracted in 8 dogs and, after 12 weeks, 2 machined (Neodent Titamax, Brazil) and 2 micro implants (Neodent Titamax Porous, Brazil) were placed in each animal. Biopsies were taken at 3 and 8 weeks post-implantation and stained with Stevenel's blue and Alizarin red for histomorphometric measurements of bone-to-implant contact (BIC), bone area between threads (BABT) and bone area within the mirror area (BAMA). Data were analyzed statistically by two-way ANOVA (&#945;=0.05). While at 3 weeks micro implants exhibited significantly more BIC than machined ones (55 &plusmn; 12.5% and 35.6 &plusmn; 15%, p<0.05), no significant difference in such parameter was detected at 8 weeks (51.2 &plusmn; 21% and 48.6 &plusmn; 18.1%, p>0.05). There were no significant differences in BABT and BAMA between the implants. Micro surfaces promoted higher contact osteogenesis. These data indicate that this commercial micro Ti implant surface enhances contact osteogenesis at an early post-implantation period when compared to the machined one.Estudos recentes demonstram que implantes nacionais de titânio (Ti) usinados e micro-rugosos apresentam padrões adequados de produção. O objetivo deste estudo foi de avaliar a neo-formação óssea in vivo em 2 tipos diferentes de implantes colocados em mandíbulas de cães. Trinta e dois implantes rosqueáveis de Ti foram utilizados neste estudo. Os pré-molares mandibulares de 8 cães foram extraídos e, após 12 semanas, 2 implantes usinados (Neodent Titamax) e 2 implantes micro-rugosos (Neodent Titamax Porous) foram colocados em cada animal. Após 3 e 8 semanas da implantação os espécimes foram biopsiados, corados com Stevenel's blue e Alizarin red e analisados histomorfometricamente quanto à porcentagem de contato-osso-implante (COI), área de osso mineralizado entre as roscas (OMER) e área de osso mineralizado na área em espelho (OMAE). Os resultados foram analisados estatisticamente pelo teste de ANOVA a dois fatores. Os implantes micro-rugosos apresentaram maior COI do que os implantes controle em 3 semanas (55,0 &plusmn; 12,5% e 35,6 &plusmn; 15,0%; p<0,05), enquanto não houve diferença em 8 semanas (51,2 &plusmn; 21,0% e 48,6 &plusmn; 18,1%; p>0,05). Não houve diferença quanto ao OMER e OMAE. Esses dados nos indicaram que os implantes micro-rugosos utilizados neste estudo aumentam a osteogênese de contato nos períodos iniciais pós-implantação quando comparados com implantes usinados.(FAPESP) São Paulo Research Foundation(CNPq) The National Council for Scientific and Technological Developmen

Clinical, microscopic and imaging findings associated to Mccune-Albright syndrome: report of two cases

McCune-Albright syndrome is characterized by the triad café-au-lait cutaneous spots, polyostotic fibrous dysplasia and endocrinopathies. This article presents two cases of McCune-Albright syndrome in a middle-aged woman and a young girl. Both patients presented café-au-lait spots on the face and other parts of the body and expansion of the mandible with radiopaque-radiolucent areas with ground-glass radiographic appearance, and were diagnosed as having fibrous dysplasia and endocrine disorders. The patient of Case 1 had fibrous dysplasia on the upper and lower limbs, thorax, face and cranium, early puberty, hyperglycemia, hyperthyroidism and high serum alkaline phosphatase levels. The patient of Case 2 presented lesions on the upper limbs and evident endocrine disorders. In both cases presented in this article, the initial exam was made because of the mandibular lesion. However, a diagnosis of fibrous dysplasia must lead to investigation of the involvement of other bones, characterizing polyostotic fibrous dysplasia, which is manifested in a number of diseases. An accurate differential diagnosis is mandatory to determine the best treatment approach for each case.A Síndrome de McCune-Albright é caracterizada pela tríade manchas café-com-leite na pele, displasia fibrosa poliostótica e endocrinopatias. Este artigo apresenta dois casos de Síndrome de McCune-Albright em uma mulher de meia idade e em uma menina. Ambos apresentavam manchas café-com-leite na face e em outras partes do corpo, expansão da mandíbula com área radiopaca-radiolúcida com aspecto de vidro despolido na radiografia, com o diagnóstico de displasia fibrosa, e desordens endócrinas. O paciente do Caso 1 apresentava displasia fibrosa nos membros inferiores e superiores, tórax, face e crânio, puberdade precoce, hiperglicemia, hipertireoidismo e elevação da fosfatase alcalina no sangue. O paciente do Caso 2 apresentava lesões nos membros superiores e desordem endócrina evidente. Em ambos os casos apresentados neste artigo, o exame inicial foi realizado devido à lesão mandibular. Contudo, o diagnóstico de displasia fibrosa deve conduzir a pesquisa de envolvimento de outros ossos, caracterizando a displasia fibrosa poliostótica, que se manifesta em um grande número de doenças. O diagnóstico diferencial preciso é fundamental para determinar o tratamento adequado a cada caso

Postura de cabeça nas deformidades dentofaciais classe II e classe III Head posture in the presence of class II and class III dentofacial deformities

OBJETIVO: este estudo investiga se existe diferença entre grupos com diferentes deformidades dentofaciais (padrão classe II e classe III) e o grupo sem a deformidade em relação à postura de cabeça. MÉTODO: participaram deste estudo, voluntariamente, 25 pacientes (entre 16 e 40 anos). Dez pacientes com diagnóstico de deformidade dentofacial classe II e 15 pacientes com o diagnóstico de classe III esquelética e 15 voluntários sadios, com equivalência em sexo e idade ao grupo de deformidade, formando o grupo controle. Primeiramente foi realizada a inspeção da postura de cabeça. Logo em seguida foi realizada a avaliação postural de cabeça por meio da fotografia postural (fotogrametria). RESULTADOS: não houve diferença significante (p>0,05) entre os grupos em relação à avaliação postural utilizando-se a fotogrametria. Já em relação à avaliação postural pela inspeção clínica, observou-se uma postura anterior de cabeça nos indivíduos com a deformidade dentofacial padrão classe II, comparados ao padrão classe III (p = 0,001) e ao grupo controle (p = 0,001). Foi visto também que o grupo deformidade classe II apresentou um percentual inferior de indivíduos com posição neutra de cabeça comparado ao grupo deformidade classe III (p = 0,008) e ao grupo controle (p = 0,001). CONCLUSÃO: indivíduos com deformidade dentofacial classe II podem apresentar uma anteriorização de cabeça. Não há influência da deformidade no aumento ou na redução do ângulo cabeça-pescoço, analisado por meio da fotogrametria.PURPOSE: this study investigates whether there is a difference in head posture between groups with different dentofacial deformities (class II and class III) and a group with no deformity. METHOD: 25 volunteers aged from 16 to 40 year old took part in the study. Ten patients had a diagnosis of class II dentofacial deformity, 15 had a diagnosis of class III skeletal deformity, and 15 healthy volunteers matched for sex and age to the group with deformity were used as a control group. Head posture was first checked, followed by evaluation through postural photography (photogrammetry). RESULTS: there was no significant difference (p>0.05) between groups regarding postural evaluation by photogrammetry. However, postural evaluation using clinical inspection, revealed anterior head posture among subjects with class II dentofacial deformity compared to subjects with class III deformity (p = 0.001) and to control group (p = 0.001). The percentage of class II dentofacial deformity subjects with neutral head posture was also lower compared to class III dentofacial deformity (p = 0.008) and to control group (p = 0.001). CONCLUSION: subjects with class II dentofacial deformity may show anteriorization of the head. There is no influence of the deformity on the increase or reduction of the head-neck angle when analyzed by photogrammetry

Immunohistochemical, tomographic, and histological study on onlay bone graft remodeling. Part III: allografts

Objective In the last decades aroused the interest for bone tissue bank as an alternative to autogenous grafting, avoiding donor sites morbidity, surgical time, and costs reduction. The purpose of the study was to compare allografts (ALg) with autografts (AUg) using histology, immunochemistry, and tomographic analysis. Material and methods Fifty-six New Zealand White rabbits were submitted to surgical procedures. Twenty animals were donors and 36 were actually submitted to onlay grafting with ALg (experimental group) and AUg (control group) randomly placed bilaterally in the mandible. Six animals of each group were sacrificed at 3, 5, 7, 10, 20, and 60 postoperative days. Immunolabeling was accomplished with osteoprotegerin (OPG); receptor activator of nuclear factor-k ligand (RANKL); alkaline phosphatase (ALP); osteopontin (OPN); vascular endothelial growth factor (VEGF); tartrate-resistant acid phosphatase (TRAP); collagen type I (COL I); and osteocalcin (OC). Density and volume of the grafts was evaluated on tomography obtained at the surgery and sacrifice. Results The ALg and AUg exhibited similar patterns of density and volume throughout the experiments. The intra-group data showed statistical differences at days 7 and 60 in comparison with other time points (P = 0.001), in both groups. A slight graft expansion from fixation until day 20 (P = 0.532) was observed in the AUg group and then resorbed significantly at the day 60 (P = 0.015). ALg volume remained stable until day 7 and decreased at day 10 (P = 0.045). The light microscopy analysis showed more efficient incorporation of AUg onto the recipient bed if compared with the ALg group. The immunohistochemical labeling picked: at days 10 and 20 with OPG in the AUg group and at day 7 with TRAP in the ALg group (P = 0.001 and P = 0.002, respectively). Conclusions ALg and AUg were not differing in patterns of volume and density during entire experiment. Histological data exhibit more efficient AUg incorporation into recipient bed compared with the ALg group. Immunohistochemistry outcomes demonstrated similar pattern for both ALg and AUg groups, except for an increasing resorption activity in the ALg group mediated by TRAP and in the AUg group by higher OPG labeling. However, this latter observation does not seem to influence clinical outcomes

Mandibular ameloblastoma treated by bone resection and imediate reconstruction

O ameloblastoma multicístico acomete principalmente pacientes adultos, entre a terceira e a sétima década de vida, freqüentemente na região posterior de mandíbula. A ressecção de um segmento mandibular, sem reconstrução adequada, produz grave seqüela estética e funcional levando a uma perda da qualidade de vida. O objetivo desta apresentação é mostrar que o tratamento multidisciplinar do ameloblastoma possibilita radicalidade oncológica associada à completa reconstrução da área lesada. Apresentamos um paciente de 47 anos, acometido por um ameloblastoma em região posterior de mandíbula tratado com ressecção completa de um segmento mandibular. A reconstrução no mesmo tempo operatório utilizou enxerto ósseo de crista ilíaca fixado com placas e parafusos de titânio. Após oito meses completou-se a reabilitação com implantes de elementos dentários na área do enxerto. As vantagens deste procedimento incluem a diminuição do risco de recidivas pelo uso da ressecção segmentar, reconstrução mandibular confiável e diminuição do número de procedimentos cirúrgicos, permitindo completa reabilitação em um período mais curto de tempo.Multicystic ameloblastoma mainly affects adult patients between the third and seventh decades of life, frequently in the posterior region of the mandible. The resection of a mandible segment without adequate reconstruction produces serious esthetic and functional sequelae leading to a loss of quality of life. The objective of this study is to show that multidisciplinary treatment of ameloblastomas helps in total lesion excision associated with complete reconstruction of the damaged area. We present a 47-year-old male patient with an ameloblastoma in the posterior mandible who was treated with complete resection of a mandibular segment. Reconstruction, carried out during the same surgical procedure, was performed using an iliac crest bone graft fixed with titanium plates and screws. Rehabilitation was completed eight months later with teeth implants in the grafted area. The advantages of this procedure include recurrence risk reduction due to segmental resection, reliable mandibular reconstruction and less surgical procedures, allowing full rehabilitation within a shorter period of time

Quantitative ultrasound at the hand phalanges in patients with bisphosphonate-related osteonecrosis of the jaws

Patients with bisphosphonate-related osteonecrosis of the jaws (BRONJ) who received intravenous or oral bisphosphonates (BP) were selected for determination of their bone microarchitecture as a risk predictor of BRONJ development. The diagnosis of BRONJ was made based on clinical and radiographic findings. The control group consisted of healthy patients. All patients underwent quantitative and qualitative ultrasound measurements of bone at the hand phalanges carried out using the DBM Sonic BP. Ultrasound bone profile index (UBPI), amplitude-dependent speed of sound (AD-SoS), bone biophysics profile (BBP), and bone transmission time (BTT) were measured. The BRONJ group consisted of 17 patients (62 ± 4.24; range: 45-82); 10 (58.8%) were male and seven (41.1%) were female, of whom 11 (64.7%) suffered from multiple myeloma, three (17.6%) from osteoporosis, one (5.8%) from prostate cancer, one (5.8%) from kidney cancer, and one (5.8%) from leukemia. Fourteen (82.3%) of them received intravenous BP whereas three (17.6%) received oral BP. Nine (9/17; 52.9%) patients developed bone exposure: two in the maxilla and seven in the mandible. Regarding quantitative parameters, Ad-SoS was low in the BRONJ group, but not significant. The UBPI score was significantly reduced in BRONJ patients with exposed bone when compared to controls (0.47 ± 0.12 vs. 0.70 ± 0.15; p = 0.004). The present study demonstrated that quantitative ultrasound was able to show bone microarchitecture alterations in BRONJ patients, and suggests that these analyses may be an important tool for early detection of bone degeneration associated with BRONJ