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Osteoradionecrosis (ORN) of the jaw is a complication of radiation therapy for head and neck cancers. We report a case of ORN of the posterior maxilla treated with Er: YAG laser and a pedicled buccal fat pad (bichat bulla adipose) flap. A 69-year-old man presented complaining of pain on left maxilla. He had received high-dose radiotherapy (90 Gy) for squamous cell carcinoma of the left soft palate 2 years earlier. Clinical and radiographic examinations revealed ORN of the left maxillary molar region and maxillary sinusitis. Daily home care consisted of 0.9% saline irrigation and 0.8% H2O2 gel application. Sequestrectomy and tooth extraction were followed by debridement with Er: YAG laser and repair with a pedicled buccal fat pad flap. Complete resolution of ORN and maxillary sinusitis was established one year postsurgically. The excellent clinical outcome suggests that Er: YAG laser debridement and pedicled buccal fat pad flap are a viable option to treat ORN of the posterior maxilla.
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Tecido Adiposo/transplante , Lasers de Estado Sólido/uso terapêutico , Doenças Maxilares/cirurgia , Osteorradionecrose/cirurgia , Retalhos Cirúrgicos/transplante , Idoso , Autoenxertos/transplante , Carcinoma de Células Escamosas/radioterapia , Desbridamento/métodos , Seguimentos , Humanos , Peróxido de Hidrogênio/uso terapêutico , Masculino , Doenças Maxilares/tratamento farmacológico , Sinusite Maxilar/tratamento farmacológico , Sinusite Maxilar/cirurgia , Osteorradionecrose/tratamento farmacológico , Neoplasias Palatinas/radioterapia , Irrigação Terapêutica/métodos , Extração Dentária/métodos , Resultado do TratamentoRESUMO
BACKGROUND: Implantology represents the therapy of choice for the rehabilitation of a partially or totally edentulous jaw in a healthy patient. Nowadays, it is possible to exploit of modern preoperative planning software, increasingly precise radiographic examinations (CBCT) and CAD/CAM technologies that allow designing devices directly on the computer to be sent to a milling center which produces the desired product, such as stereolithographic templates. METHODS: The prospective clinical study in question aims to evaluate the accuracy between two different surgical guides using peek and metal guide bushings. Twenty-nine implants were placed: for the control group, 17 3i, T3 implants were used, while for the test group, 12 Xive S plus implants were used. RESULTS: The result obtained shows that the deviations in the distribution of the control group and the test group are the same in the apical-coronal, vestibulo-palatal and mesio-distal direction. For the control group, the mean deviation was 1.394±0.644923 at the entry point of the implants and 1.85655±1.0765 at the most apical point of the implants. For the test group the mean deviation was 1.10157±0.312721 at the entry point of the implants and 1.54514±0.572100 at the most apical point of the implants. CONCLUSIONS: The peek guide bushings have the same deviation as the metal ones. There is no difference in the method used, but precision must be sought in other elements, such as the patient's anatomy and maximum precision in the guide production phase.
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Benzofenonas , Implantes Dentários , Polímeros , Cirurgia Assistida por Computador , Humanos , Implantação Dentária Endóssea/métodos , Estudos Prospectivos , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional/métodosRESUMO
Mesenchymal stem cells (MSCs) are multipotent cells that are able to differentiate into mesodermal lineages (osteogenic, adipogenic, chondrogenic), but also towards non-mesodermal derivatives (e.g. neural cells). Recent in vitro studies revealed that, in the absence of any kind of differentiation stimuli, undifferentiated MSCs express neural differentiation markers, but the literature data do not all concur. Considering their promising therapeutic potential for neurodegenerative diseases, it is very important to expand our knowledge about this particular biological property of MSCs. In this study, we confirmed the spontaneous expression of neural markers (neuronal, glial and progenitor markers) by undifferentiated human MSCs (hMSCs) and in particular, we demonstrated that the neuronal markers ßIII-tubulin and NeuN are expressed by a very high percentage of hMSCs, regardless of the number of culture passages and the culture conditions. Moreover, the neuronal markers ßIII-tubulin and NeuN are still expressed by hMSCs after in vitro osteogenic and adipogenic differentiation. On the other hand, chondrogenically differentiated hMSCs are negative for these markers. Our findings suggest that the expression of neuronal markers could be common to a wide range of cellular types and not exclusive for neuronal lineages. Therefore, the expression of neuronal markers alone is not sufficient to demonstrate the differentiation of MSCs towards the neuronal phenotype. Functional properties analysis is also required.
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Adipogenia , Biomarcadores/metabolismo , Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Neurônios/metabolismo , Osteogênese , Linhagem da Célula , Separação Celular , Células Cultivadas , Citometria de Fluxo , Imunofluorescência , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Humanos , Immunoblotting , Mesoderma/metabolismo , Neuraminidase/metabolismo , Neuroglia/citologia , Neuroglia/metabolismo , Neurônios/citologia , Tubulina (Proteína)/metabolismoRESUMO
The spontaneous expression of neural markers by mesenchymal stem cells (MSCs) has been considered to be a demonstration of MSCs' predisposition to differentiate towards neural lineages. In view of their application in cell therapy for neurodegenerative diseases, it is very important to deepen the knowledge about this distinctive biological property of MSCs. In this study, we evaluated the expression of neuronal and glial markers in undifferentiated rat MSCs (rMSCs) at different culture passages (from early to late). rMSCs spontaneously expressed neural markers depending on culture passage, and they were coexpressed or not with the neural progenitor marker nestin. In contrast, the number of rMSCs expressing mesengenic differentiation markers was very low or even completely absent. Moreover, rMSCs at late culture passages were not senescent cells and maintained the MSC immunophenotype. However, their differentiation capabilities were altered. In conclusion, our results support the concept of MSCs as multidifferentiated cells and suggest the existence of immature and mature neurally fated rMSC subpopulations. A possible correlation between specific MSC subpopulations and specific neural lineages could optimize the use of MSCs in cell transplantation therapy for the treatment of neurological diseases.
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Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurogênese/fisiologia , Neurônios/citologia , Neurônios/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: The aim of this study was to evaluate the accuracy of implant placement using static guided surgery. Two methods of measuring accuracy were compared, the superimposition of CBCT and the non-radiological Superimposition Touch Absolute Precision (S.T.A.P.) method. METHODS: In this prospective clinical study 23 implants were placed with static surgical template using a flapless technique and postextractive procedure. Six months after surgery, a postoperative CBCT was performed to assess the position of the implants and at the same time dental impressions were taken for the final prosthesis. The plaster models made at this stage have made it possible to obtain the position of the implants inserted using the probe technology. Preoperative and postoperative data were superimposed, deviations in the three dimensions of the space were calculated. The differences between the two measurement methods were assessed. RESULTS: The study showed no statistically significant differences between the two methods of measuring accuracy at the implant platform level, apex, or angles. The average real deviation detected at the implant platform level is 1.16±0.58 mm with CBCT, 1.22±0.55 mm with the S.T.A.P. method; at the apex level is 1.48±0.98 mm with CBCT, 1.47±0.72 mm with the S.T.A.P. method. The average difference between CBCT and S.T.A.P. method for real deviation is 0.06±0.75 mm at the platform level and 0.007±1.24 mm at the apex level. CONCLUSIONS: The present study showed that measuring accuracy by S.T.A.P. method was comparable to that obtained by CBCT superimposition.
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Implantes Dentários , Tomografia Computadorizada de Feixe Cônico Espiral , Cirurgia Assistida por Computador , Tomografia Computadorizada de Feixe Cônico , Implantação Dentária Endóssea/métodos , Estudos Prospectivos , Cirurgia Assistida por Computador/métodosRESUMO
In thirteen different dental clinics in Singapore, Spain, Czech Republic and Italy, 504 patients were selected, and 483 dental implants were placed in maxillary sites after alveolar socket preservation (ASP) procedures with an autologous demineralized tooth extracted as graft material from an innovative Tooth Transformer device was obtained. All procedures used were reported in n°638 Ethical Committee surgical protocol of University of Chieti and approved. After 4 months, at dental implant placing, bone biopsies were performed to evaluate the histologic outcomes, and 12 months after implant loading, global implant survival rate, failure percentage and peri-implant bone loss were detected. After ASP, only 27 post-operative complications were observed and after 4 months, bone biopsy histomorphometric analysis showed a high percentage of bone volume (BV) 43.58 (±12.09), and vital new bone (NB) 32.38 (±17.15) with an absence of inflammation or necrosis areas. Twelve months after loading, only 10 dental implants failed (2.3%), with a 98.2% overall implant survival rate, nine cases showed mucositis (1.8%) and eight showed peri-implantitis (1.6%). At mesial sites, 0.43 mm (±0.83) of bone loss around the implants was detected and 0.23 mm (±0.38) at the distal sites with an average value of 0.37 mm (±0.68) (p > 0.568). Several studies with a longer follow-up will be necessary to confirm the preliminary data observed. However, clinical results seem to suggest that the post-extraction socket preservation procedure using innovative demineralized autologous tooth-derived biomaterial may be a predictable procedure to produce new vital bone able to support dental implant rehabilitation of maxilla edentulous sites.
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AIM: Thoracoscopic lobectomy is superior to thoracotomy, but the evidence for this assumption is low. We present a comparison between thoracotomy and thoracoscopy in term of postoperative complications, mortality, postoperative pain, hospital stay and quality of life. PATIENTS AND METHODS: This is a retrospective analysis of 224 lobectomies in 24-months. 128 patients (57.1%) were operated by thoracotomy; 96 patients (42.9%) by videothoracoscopy. RESULTS: Major complications were observed in 4/128 (3.1%) in thoracotomy group and in 1/96 (1%) in thoracoscopy. Minor complications were observed in 38/128 patients (29.7%) in the thoracotomy, and in 16/96 (16.7%) thoracoscopy. Thoracoscopy patients had a shorter hospital stay. CONCLUSION: Our study shows an advantage of thoracoscopy over thoracotomy but further studies are needed.
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Neoplasias Pulmonares/cirurgia , Pneumonectomia/métodos , Complicações Pós-Operatórias/epidemiologia , Qualidade de Vida , Cirurgia Torácica Vídeoassistida , Toracotomia , Humanos , Dor Pós-Operatória/epidemiologia , Estudos RetrospectivosRESUMO
The choroid is the most common site for intraocular metastatic di sease. Orbital metastasis as metastatic site of lung adenocarcinoma is very rare and in literature a very exiguous number of cases is present. This is a case report of a woman with history of lung adenocarcinoma and, after surgery, detection of a choroidal mass described as lung metastasis, responding to Gefinitib therapy. However a biopsy was not performed. After two years there was a great dimension decrement of the lung metastasis but she is still suffering from recurrent pleural effusion, with pleural thickenings biopsied and diagnosed as recurrences of disease.
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Adenocarcinoma de Pulmão/secundário , Neoplasias da Coroide/secundário , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
INTRODUCTION: Prolonged air leak (PAL) is one of the most common postoperative complications after lung surgery. It is associated with increased significant morbidity, lower quality of life, longer hospital stay and higher hospital costs. Since its great clinical and economic burden, it is important to establish the feasibility and the effectiveness of the routinary preventive use of a fibrin sealant in order to reduce the incidence of prolonged air leaks. PATIENTS AND METHODS: This is a randomized study on 189 adult patients - 118 men (62.4%) and 71 women (37.6%) aged from 39 to 87 y.o. (mean age 68.3 y.o.) - who underwent lung surgery (lobectomy or bilobectomy) with intraoperatory detection of air leakage, from January 2013 to December 2017, at Department of Thoracic Surgery in "Ospedale Maggiore Carlo Alberto Pizzardi" (Bologna, Italy) and Department of Thoracic Surgery in "Paolo Giaccone" Teaching Hospital (Palermo, Italy). Patients were randomly assigned to the "Glue" arm (90 patients) or the "Control" group (99 patients). We only used stapler or manual suture to achieve aerostasis. In addition, we used a fibrin sealant ("glue") to cover the suture line on patients in the "Glue" arm. The primary endpoints were incidence of prolonged air leaks, days with chest tube and mean hospital stay. RESULTS: In the "Glue" arm we experienced only 1 prolonged air leak (1.1%), while in the "Control" group there were 8 leaks (8.1%). Patients kept chest tube for average 4.15 days in the "Glue" arm and 4.45 days in the "Control" group. The mean hospital stay was average 7.4 days for the "Glue" arm, while 9.1 days in the "Control" group. CONCLUSIONS: According to our experience it seems that the routinary preventive use of a fibrin sealant results in a lower incidence of prolonged air leaks, a shorter hospital stay with lower hospital costs, representing a cost-effective, feasible and effective system to decrease morbility and mortality among surgical patients.
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Ar , Fístula Anastomótica/prevenção & controle , Adesivo Tecidual de Fibrina/uso terapêutico , Pneumonectomia/efeitos adversos , Adesivos Teciduais/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Tubos Torácicos , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pneumonectomia/métodos , Qualidade de Vida , Técnicas de SuturaRESUMO
Primary leiomyosarcomas of the lung are tumors. We report a case of 49-year old female with history of cough, breathless at rest, right sided chest pain. Chest CT showed a huge (16 cm) mediastinal mass located on the right mediastinum encasing the right main pulmonary artery and infiltrating the main right bronchus and pericardium. The tumor was resected with combined pericardiectomy and pnemonectomy via hemiclamshell incision. This surgical access provided an adequate exposure of the chest "blind zones" and it allowed a radical and safe surgical resection of lung, pleura, pericardium and diaphragm. The final diagnosis showed a low grade differentiation leiomyosarcoma.
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Leiomiossarcoma/cirurgia , Neoplasias do Mediastino/cirurgia , Feminino , Humanos , Leiomiossarcoma/diagnóstico por imagem , Leiomiossarcoma/patologia , Neoplasias do Mediastino/diagnóstico por imagem , Neoplasias do Mediastino/patologia , Ilustração Médica , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Carga TumoralAssuntos
Angioedemas Hereditários , Assistência Odontológica para Doentes Crônicos , Adulto , Perda do Osso Alveolar/etiologia , Angioedemas Hereditários/complicações , Periodontite Crônica/etiologia , Periodontite Crônica/terapia , Proteína Inibidora do Complemento C1/genética , Proteína Inibidora do Complemento C1/uso terapêutico , Danazol/uso terapêutico , Edema/etiologia , Antagonistas de Estrogênios/uso terapêutico , Feminino , Defeitos da Furca/etiologia , Humanos , Extração Dentária/efeitos adversos , Mobilidade Dentária/etiologiaRESUMO
Laser therapy and fluorescence-guided surgery are highly reliable and predictable methods, but their combination has not been found to yield useful outcomes. We present a new therapeutic approach combining fluorescence-guided Er:YAG laser ablation with Nd:YAG/diode laser biostimulation for bisphosphonate-related osteonecrosis of the jaw (BRONJ). A woman was treated with zoledronic acid for bone metastasis from clear cell renal cell carcinoma and subsequently developed BRONJ in the left jaw. The management protocol included perioperative medical therapy (1% chlorhexidine gel, rifamycin, and doxycycline for 10 preoperative and 7 postoperative days), Er:YAG laser ablation guided by doxycycline fluorescence in vital bone under UV light, and Nd:YAG/diode laser biostimulation. The lesion regressed from stage 3 to stage 1 and showed nearly complete healing after laser therapy (3 and 23 cycles of ablation and biostimulation, respectively). These preliminary findings suggest the feasibility of the new approach, which is minimally invasive and biostimulative and causes very low morbidity.
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Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/radioterapia , Lasers de Estado Sólido/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos , Doenças Mandibulares/radioterapia , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/diagnóstico por imagem , Feminino , Humanos , Doenças Mandibulares/diagnóstico por imagem , Pessoa de Meia-Idade , Radiografia Panorâmica , Tomografia Computadorizada por Raios XRESUMO
AIM OF THE STUDY: Implant rehabilitation delivered in accordance with the traditional protocol has proven to be highly predictable and acceptable (1). Nevertheless, the application of immediate loading on post-extraction implants, especially for aesthetic zones, has now considerably increased (2). The aim of this work is to illustrate the immediate loading of implants placed in the aesthetic zone through tapered design fixtures with microgeometry of a high degree of porosity inserted at the same time or 4-8 weeks from dental avulsion (TSA® Advance, Phibo®). MATERIALS AND METHODS: A total of 15 implant fixtures of which 8 at an interval of 4-8 weeks from extraction (type 2) and the remaining according to the immediate post-extraction technique (type 1) were positioned. All implants were prosthesized within 24 hours from the placement. Definitive crowns replaced provisional restorations after 20-24 weeks. After 4 and 12 months from implant insertion, the following parameters were assessed: X-ray image, pain, mobility or suppuration, soft tissue condition and aesthetic appearance. RESULTS: Percentage of osseointegration was 93.75%, and 53.5% of the osseointegrated fixtures was type 2. No statistically significant difference between the mean ISQ values for implants of type 1 and 2 both in the post-operative period and after 12 months was evident, indicating that the timing of insertion did not affect the achievement of stability for the implant fixtures tested in our study. Immediate post-extraction implants showed a greater propensity for gingival recession and a peri-implant radiolucency greater than those placed at an interval of 4-8 weeks. The values obtained for the PES/WES and the subjective evaluation of the analyzed sample showed the considerable aesthetic value and the high level of satisfaction guaranteed by the implant technique illustrated. CONCLUSION: Although well-designed, high quality, randomized clinical trials are still needed as well as the requirement to establish a common, complete, and reproducible index for the evaluation of aesthetic outcome, immediate/early placement and loading of a single TSA® Advance, Phibo® may be considered a valuable and predictable option in terms of implant success as well as hard and soft tissue stability.
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AIM OF THE STUDY: The odontogenic sinusitis has an incidence between 38 and 40.6%. Increased risk of maxillary sinusitis has been reported with the presence of periapical abscesses, periodontal disease, dental trauma, tooth extraction and implant placement when the sinusal membrane is perforated. MATERIALS AND METHODS: A patient with odontogenic maxillary sinusitis associated with oro-nasal fistula was treated. RESULTS: The follow-up at six months showed the complete resolution of maxillary sinusitis, palatal fistula got closed and pain symptoms disappeared. CONCLUSION: This case report describes a rare complication of odontogenic maxillary sinusitis: the oro-nasal fistula.
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AIM OF THE STUDY: Reconstruction of segmental defects and the atrophic maxilla and mandible is performed using various techniques. Bone substitutes have received a wealth of reports in the literature demonstrating a long-term success when used in alveolar bone augmentation procedures. MATERIALS AND METHODS: We reviewed articles comparing TiMesh GBR technique with different percentage of bone: autogenous bone alone (AB); anorganic bovine bone alone (ABB); 50:50 or 70:30. From an initial pool of 122, we selected 14 studies. ANOVA followed by Tukey HSD test was used for statistical analysis. RESULTS: We present a table analysing fundamental parameters to value a successful GBR therapy. Autogenous bone remains the gold standard in GBR technique with TiMesh; however, the combination between AB/ABB in relation 50:50 and 70:30 allows reducing surgical cost exploiting properties of eterologous bone. CONCLUSION: The use of autologous bone is associated with a height and width gain of bone, which are greater compared to other techniques, with a lower exposure of the mesh and a lower bone resorption. The use of heterologous graft leads to a lower bone earn and to percentage of resorption greater than autologous graft but does not differ from the gain and resorption of the bone of AB/ABB in percentage 50:50 and 70:30.
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AIM OF THE STUDY: The change in anatomy and physiology resulting from radical mandible surgery is often exacerbated by radiation therapies that make the mucosa atrophic and susceptible to irritation and ulceration rendering the task of areating functional complete dentures for edentulous subjects very challenging to prosthodontists. The aim of this study is to describe an implant supported denture rehabilitation in an edentulous hemimandibulectomized patient with a singular prosthetic design in order to compensate for the lack of a condylar process. MATERIALS AND METHODS: The subject of the clinical case, had a history of squamous cell carcinoma of the right tonsillar region for which it was subjected to a hemimandibulectomy and was primarily rehabilitated with an over denture mounted onto a bar furnished by a resin condylar eminence in articulation with the glenoid fossa of the upper denture. The need to provide greater stabilization for the upper prosthesis led to a maxillary implant insertion and to the realization of a new joint connection that was constituted inferiorly by a titanium condyle and superiorly by a teflon acetabulum. DISCUSSION: The prosthetic balance guaranteed by the second rehabilitation greatly affected the biomechanics of mastication leading to a reduction of eccentric interferences, a stabilization of centric occlusion, and a lowering of intensity contraction by masticatory muscles. This difference is well represented by two and three-dimensional plans obtained from the application of a T-Scan III device. CONCLUSIONS: The rehabilitative solution proposed was effective in resolving the lateral deviation, in relieving masticatory and speech discomfort, as well as restoring an aesthetically acceptable appearance in a hemimandibulectomized and not reconstructed patient.
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AIM OF THE STUDY: Solitary central osteomas of the jaw seem to be especially rare lesions; since 1955, only 12 cases have been reported and 4 of these were located in the maxilla. Osteomas are benign osteogenic lesions considered as real tumours but without infiltrative or metastatic potential. Their growth potential is usually limited, but certain rare and large cases of peripheral osteoma are described in literature. Although surgery is recommended, there are no reports of malignant transformation. In this study, we describe successful implant rehabilitation in a patient with a central osteoma of the maxilla with immediate loading in a fresh extraction socket. MATERIALS AND METHODS: The report concerns a 33-year-old woman with a compromised deciduous first molar in the left premolar region of the maxilla; an asymptomatic bony expansion of the palatal and vestibular sides of the left canine/premolar/molar area of the maxilla and by radiograph revealed a well-defined radiopaque mass. An immediate non-occlusal loading was performed, and complete loading of the implant was completed five months later. DISCUSSION AND CONCLUSION: The pathogenesis of these osteomas is unclear. Several authors reported a clear history of traumatic events, but others had no history of previous trauma or contributory medical factors. Since in our case no cancer growth happened over a period of more than four years, we decided to perform an immediate loading procedure during the implant rehabilitation. The outcome was successful.
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AIMS: the assessment of the limit dose for the organs at risk in external radiotherapy is a fundamental step to guarantee an optimal risk-benefit ratio. The aim of this study was to assess, through contouring the single dental cavities, the absorbed radiation dose on irradiated alveolar bones during the treatment of cervico-facial tumours, so as to test the correlation between the absorbed dose of radiation at alveolar level and the level of individual surgical risk for osteonecrosis. MATERIALS AND METHODS: we selected 45 out of 89 patients on the basis of different exclusion criteria. Nine of these patients showed evidence of osteoradionecrosis. The patients were treated either with 3D conformational radiation therapy (3D-CRT) or with intensity-modulated radiation therapy (IMRT), there after alveolar bones were contoured using computed axial tomography (CAT scans) carried out following oncological and dental treatment. The dose-volume histograms (DVH) were obtained on the basis of such data, which included those relating to the dental cavities in addition to those inherent to the tumours and the organs at risk. RESULTS: all patients, irrespective of type of treatment, received an average of 60 to 70 grays in 30/35 sittings. The patients treated with IMRT showed higher variation in absorbed radiation dose than those treated with 3D-CRT. The alveolar encirclement allowed the assessment of the absorbed radiation dose, and consequently it also allowed to assess the individual surgical risk for osteonecrosis in patients with head and neck tumours who underwent radiography treatment. CONCLUSIONS: the study of DVH allows the assessment of limit dose and the detection of the areas at greater risk for osteoradionecrosis before dental surgery.
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PURPOSE: currently, head and neck irradiation is not considered an absolute contraindication for implant placement (1), especially due to the transition from conventional to conformal radiotherapy. However, there is a difference in the success rate of implant placement between irradiated and non-irradiated bones (5). Successful osseointegration is mainly affected by the total dose of radiation (6). The main purpose of this study was to minimize problems related to radiation dose by evaluating in advance the most suitable site for implant insertion on the basis of the mean absorbed dose. Additional aims were: to estimate the appropriate timing for implant insertion in irradiated bones, to analyze the difference in stability between maxilla and mandible, and to evaluate the success of implants with wrinkled microgeometry and increased layer of TiO(2). MATERIALS AND METHODS: five patients who had been irradiated for head and neck cancer using intensity-modulated radiotherapy (IMRT) were recruited for our study. Surgical procedures were performed following a pre-surgical evaluation of the correct insertion position of implant fixtures. The latter was based on a scrutiny of dose-volume histograms (DVH) developed by a team of experts in medical physics and radiotherapists after dentists had contoured the volumes of interest. Student's t test and Pearson's correlation test were used for comparison and correlation between the variables considered. RESULTS: the percentage of osseointegration was 100%, which supports the usefulness of the adopted technique. A statistically significant difference in stability and crestal bone resorption emerged in the comparison between maxilla and mandible, but not between times of insertion. Moreover, there was a significant correlation between radiation dose and ISQ values: an increase in radiation dose corresponded to a decrease in primary stability. However, the correlation between ISQ values and implant length was not significant as well as that between primary stability and implant diameter. CONCLUSIONS: implantology guided by assessment of absorbed irradiation dose in the site to be rehabilitated can lead both to an increase in implant survival into irradiated tissue bone, and to a reduction in the incidence of ORN. However, both a larger sample size and the development of long-term prospective studies are necessary to validate the described method.
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AIMS: this work aims at demonstrating that multiple systemic conditions, in association with the development of bisphosphonate associated osteonecrosis of the jaw (ONJ), increase the risk of complications and may lead to hospitalization. For this reason the dental approach to patients with multisystem disease should be carefully managed by a team of specialists. CASE REPORT: a case of mandibular necrosis associated with intake of oral bisphosphonates in a complex systemic context is described. RESULTS AND DISCUSSION: many different diseases and systemic conditions may draw the line at oral surgery. Multiple treatments (e.g. antithrombotic, calcium channel blockers, diuretics, antibiotics and bisphosphonates) can alter the normal physiological response to tissue healing. CONCLUSIONS: patients taking bisphosphonates for more than three years (i.e. the term over which the risk of ONJ increases according to the literature, in presence of complex systemic situations, need to be carefully managed during the pre-operative, peri-operative and postoperative phases through a synergistic collaboration among different kind of specialists.