Randomized double-blind clinical trial evaluation of bone healing after third molar surgery with the use of leukocyte- and platelet-rich fibrin.

The objective of this study was to evaluate the use of leukocyte- and platelet-rich fibrin (L-PRF) in bone healing after mandibular third molar extraction. In this prospective, double-blind, split-mouth study, 34 extractions were performed. On one side, the socket was sutured primarily (control side); on the other side, L-PRF was inserted before suturing. The patients were assessed for postoperative bone regeneration, pain and soft tissue healing. The primary outcome was bone regeneration, which was performed through tomographic evaluation in the immediate postoperative period and 3 months after the procedure. The ITK-SNAP software was used for image evaluation by the intensity of grey of each voxel. Pain was analysed using a visual analogue scale (VAS), and soft tissue healing was analysed both based on the modified healing index of Landry et al., and by comparing pre- and postoperative periodontal probing at the distal of the lower second molar. The application of L-PRF improved bone density, which was higher in test group (p=0.007). There was no statistical difference related to pain or soft tissue between the groups (p>0.05). There was evidence for improved bone healing in response to L-PRF. However, to better understand the effect of L-PRF more clinical trials with larger samples are necessary.

Comparison of the accuracy of maxillary position between conventional model surgery and virtual surgical planning.

The aim of this study was to determine whether virtual surgical planning (VSP) is an accurate method for positioning the maxilla when compared to conventional articulator model surgery (CMS), through the superimposition of computed tomography (CT) images. This retrospective study included the records of 30 adult patients submitted to bimaxillary orthognathic surgery. Two groups were created according to the treatment planning performed: CMS and VSP. The treatment planning protocol was the same for all patients. Pre- and postoperative CT images were superimposed and the linear distances between upper jaw reference points were measured. Measurements were then compared to the treatment planning, and the difference in accuracy between CMS and VSP was determined using the t-test for independent samples. The success criterion adopted was a mean linear difference of <2mm. The mean linear difference between planned and obtained movements for CMS was 1.27±1.05mm, and for VSP was 1.20±1.08mm. With CMS, 80% of overlapping reference points had a difference of <2mm, while for VSP this value was 83.6%. There was no statistically significant difference between the two techniques regarding accuracy (P>0.05).

Interface dermatitis in skin lesions of Kikuchi-Fujimoto's disease: a histopathological marker of evolution into systemic lupus erythematosus?

Kikuchi's disease (KD) is a self-limiting histiocytic necrotizing lymphadenitis (HNL). Cutaneous manifestations are frequent and usually show histopathological findings similar to those observed in the involved lymph nodes. HNL with superposed histological features to KD has been described in patients with lupus erythematosus (LE), and a group of healthy patients previously reported as having HNL may evolve into LE after several months. Up to date, features to predict which HNL patients will have a self-limiting disease and which could develop LE have been not identified. In order to clarify the characteristics of skin lesions associated with KD, we report a case of HNL with evolution into systemic lupus erythematosus (SLE) and a review of previous reports of KD with cutaneous manifestations. A 17-year-old woman presented with a 4-month history of fever and generalised lymphadenopathy. A diagnosis of HNL was established based on a lymph node biopsy. One month later, she developed an erythematoedematous rash on her upper body, with histopathological findings of interface dermatitis. After 8 months, anti-nuclear antibodies (ANA) at titre of 1/320, anti-DNA-ds antibodies and marked decrease of complement levels were detected. During the following 2 years, she developed diagnostic criteria for SLE, with arthralgias, pleuritis, aseptic meningitis, haemolytic anaemia and lupus nephritis. To our knowledge, 27 cases of nodal and cutaneous KD have been reported, 9 of which later developed LE. In all these patients, the skin biopsy revealed interface dermatitis. Skin biopsy revealed a pattern of interface dermatitis in all reviewed KD cases, which evolved into LE. Even this histopathological finding was not previously considered significant; it might be a marker of evolution into LE.

Fluctuation of annexin-A1 positive mast cells in chronic granulomatous inflammation.

OBJECTIVE: We have applied here a model of chronic granulomatous inflammation to study the profile of mast cell activation and their expression of annexin-A1 in the nodular lesion. MATERIALS: Granulomatous inflammation was induced by injection of croton oil and Freund's complete adjuvant (CO/FCA) into the dorsal air-pouches of mice. Skin tissue samples were collected from control group (24 h time-point; i. e. before disease development) and 7, 14, 21, 28 and 42 days post-CO/FCA treatment. RESULTS: Histopathological analyses revealed an on-going inflammation characterized by an increased number of activated mast cells at sites of the chronic inflammatory reaction in all experimental groups. Immunohistochemical analysis showed skin mast cells highly immunoreactive for annexin-A1, both at an initial (day 7) and a delayed (day 28) phase of the inflammatory reaction. CONCLUSIONS: The observed time-dependent modulation of mast cell activation, during the granulomatous injury, indicates that multiple pathways centred on annexin-A1 might become activated at different stages of this chronic inflammatory response, including the delayed and pro-resolving phase.

[The application of the polymerase chain reaction technic for the detection of human papillomavirus sequences]. / Aplicación de la técnica de reacción en cadena de la polimerasa para la detección de secuencias de Papillomavirus humano.

The polymerase chain reaction technique was applied to detect sequences of human Papillomavirus (HPV) by controls of cellular lines of cervical cancer and of tissues obtained through biopsy with a HPV-positive clinical diagnosis. A set of consensus oligonucleotides, which are complementary to a highly conserved region within the open reading frame E1 of the viral genome of HPV affecting the cervical mucosa, was used. With these primers it was possible to amplify DNA sequences corresponding to HPV 6 and 11, considered in the low risk group, and to HPV 16, 18, 31 and 33, included in the high risk group. The study of the sensitivity of the amplification technique showed a level of detection of 3,5 viral particles per each cellular diploid genome.

Combined study of 99mTc-HMPAO SPECT and computerized electroencephalographic topography (CET) in patients with medically refractory complex partial epilepsy.

For successful surgery for drug-resistant epilepsy the site of the seizure focus needs to be known exactly. The purpose of this study was to compare the evaluation of the regional cerebral blood flow (rCBF) (localization and degree of disturbances) by 99mTc-hexamethylpropyleneamineoxime (HMPAO) single photon emission computed tomography (SPECT) with computerized electroencephalographic topography (CET) and transmission computed X-ray tomography (CT) in partial epilepsy. The study included 20 patients with medically refractory complex partial seizures. Of the 20 patients included, 15 were studied interictally, four ictally and one in both states, interictally and ictally. 99mTc-HMPAO SPECT detected rCBF changes in 95% of the patients. Interictal studies demonstrated focal areas of hypoperfusion in 93% of the patients. Ictal studies demonstrated an area of hyperperfusion in all patients. Blood flow disturbances in deeper structures of the brain, such as basal ganglia, could be detected. The areas of abnormal 99mTc-HMPAO uptake were concordant, in localization, with CET in 85% of the patients. Abnormal data with CT scans were found in only 45% of the patients. Focal lesions were found in 20% of the patients by CT scans. 99mTc-HMPAO SPECT combined with CET may be a useful screening procedure prior to referral for invasive diagnostic procedures in future management with medically refractory complex partial seizures.