323 research outputs found
Outcomes of a Pharmacological Protocol with Pentoxifylline and Tocopherol for the Management of Medication-Related Osteonecrosis of the Jaws (MRONJ): A Randomized Study on 202 Osteoporosis Patients
Medication-related osteonecrosis of the jaws (MRONJ) is a challenging situation in clinics. Previous studies have shown that pentoxifylline combined with tocopherol proved to be beneficial in patients with osteoradionecrosis, due to their antioxidant and antifibrotic properties. The aim of this randomized study was to evaluate the effect of pentoxifylline and tocopherol in patients that had developed MRONJ after tooth extractions. The study population consisted of 202 Stage I MRONJ female patients with an average age of 66.4 ± 8.3 years, who were divided into two groups. The test group (n = 108) received a pharmacological protocol with pentoxifylline and tocopherol (2 months pre-operatively and 6 months post-operatively). The control group (n = 94) had sequestrectomy operations without any pharmacological preparation. The main outcomes were clinical healing of the mucosa after 1 month, and clinical and radiographic healing of the bone lesion at 6 months. In the test group all patients had mucosal healing and there was only one relapse within 6 months. In the control group, in 17% of the patients the mucosa did not heal, 71% of the patients relapsed within two months, and 7% developed infectious complications (such as abscess or phlegmon). After 6 months, the control group patients with persisting issues were prescribed pentoxifylline and tocopherol, as in the test group. At a subsequent follow-up, all those patients healed completely. Patients were monitored for a period of 7.8 ± 0.3 years, during which no relapse or additional problems were reported. As a conclusion, pentoxifylline and tocopherol protocol seems to be beneficial in the management of MRONJ patients
Registration of dental arch models in 3D facial volumes: an alternative to CBCT acquisitions
Digital 3D models of dental arches and facial soft tissues may constitute an important support for clinicians and maxillofacial surgeons. They can be obtained using a noninvasive and harmless method1 starting from acquisitions made with a dental scanner and a stereophotogrammetric device. The aim of the study was to compare measures taken on the 3D dental and facial models with the ones obtained through a Cone Beam Computed Tomography (CBCT) device in order to evaluate the reliability of the proposed method and its repeatability. Dental and facial data about a population of seven healthy subjects just undergone CBCT have been acquired and registered twice by three operators following a protocol devised for previous works published by this same laboratory2,3. Five craniofacial and six dental landmarks have been taken into account and their linear distances have been calculated. The errors between the corresponding distances in the alternative method and in the CBCT volume have been normalized on the corresponding distance measured on the CBCT model. Statistically significant differences between repetitions and operators were found in the distances between the orbitalis and dental landmarks. We assume that these differences might have been caused by the difficulty in the positioning of the craniofacial soft-tissue landmarks on the CBCT scans. Also the delicate steps for registering the models of the dental arches could have generated errors as it has been suggested by the significant difference between experienced and inexperienced operators. It is advisable to continue the study on more patients in order to obtain a larger data set. It might also be good to consider soft tissue landmarks that are closer to the respective bone tissue ones
Um novo clorofilômetro para estimar os teores de clorofila em folhas do capim Tifton 85
O propósito deste trabalho foi verificar o desempenho de um novo clorofilometro portátil, em parcelas experimentais vegetadas com o capim-Tifton 85 (Cynodon spp.). Para tal, foi utilizado um experimento de curta duração, em que três doses de N (0,75 e 150kg de N ha-1) foram combinadas com quatro datas de amostragem (8, 16, 24 e 28 dias após um corte de uniformização). As análises foram feitas em lâminas da folha mais nova totalmente expandida. Os teores das clorofilas a, b e a+b foram quantificados espectrofotometricamente após a extração com acetona 80%, enquanto que o clorofilômetro forneceu os correspondentes valores de Índice de Clorofila Falker (ICF). As leituras do aparelho foram sensíveis tanto às doses de N quanto às datas de amostragem. Foram obtidas correlações positivas entre ambos os métodos de quantificação (clorofila a: r=0,646; b: r=0,797; e total: r=0,721), que evidenciaram a utilidade desse novo clorofilometro na determinação indireta dos teores de clorofila foliar no capim-Tifton 85
- …