Assessment of cone beam computed tomography for determining position and prognosis of interradicular mini-implants

ABSTRACT Objective: To investigate the influence of dynamic visualization of cone beam computed tomography (CBCT) scans on orthodontist's assessment of positioning status and prognosis of interradicular mini-implants (MI). Methods: Three MI positions were virtually simulated in thirty CBCT volumes: (1) MI 1 mm from the lamina dura (LD), (2) MI touching the LD and (3) MI overlapping the LD. Each position was exposed to orthodontists (n = 35) as panoramic reconstruction, sagittal reconstruction and a sequence of axial slices. Each orthodontist evaluated the MI position (relationship with the LD) and scored the prognosis using a four-point scale (the higher the score, the better the prognosis). Kappa, Friedman and Nemenyi statistics were used. Results: Statistically significant associations were detected between the prognosis scores and the type of image visualized (p<0.05). The dynamic visualization of the CBCT volume (axial slices) was associated with higher scores for prognosis and more reliable evaluation of MI positioning. Inconsistent outcomes were more frequently associated with panoramic and sagittal reconstructions. Conclusion: The dynamic visualization of axial slices allowed orthodontists to perform better assessment of MI position and considerably affected prognosis judgment.

RESUMO Objetivo: Analisar se a avaliação dinâmica de volumes de tomografia computadorizada de feixe cônico (TCFC) influencia a percepção de ortodontistas quanto à determinação da posição e do prognóstico de mini-implantes (MIs) inter-radiculares. Material e Métodos: Foram selecionados 30 volumes de TCFC, nos quais foram simuladas três formas de instalação de MIs: 1) MI a 1 mm de distância da lâmina dura (LD); 2) MI tocando a LD; e 3) MI sobreposto à LD. As imagens foram examinadas por 35 ortodontistas na forma de reconstruções panorâmicas, reconstruções sagitais e uma sequência de reconstruções axiais. Os examinadores avaliaram a relação entre o MI e a LD, e indicaram o prognóstico dos MIs instalados, usando uma escala de 4 pontos (quanto maior o escore, mais favorável o prognóstico). Os dados foram submetidos à análise estatística, por meio dos testes de Kappa, Friedman e Nemenyi. Resultados: Houve associação significativa entre o prognóstico, os tipos de imagem e as três formas de inserção dos MIs (p<0,05). A visualização dinâmica dos volumes de TCFC (reconstruções axiais) foi associada a maiores escores para o prognóstico e a avaliações mais confiáveis da posição dos MIs. Escores mais inconsistentes e discordantes foram mais associados às reconstruções panorâmicas e sagitais. Conclusão: A análise do volume tomográfico em reconstruções axiais pode melhorar a avaliação do ortodontista quanto à posição dos MIs inter-radiculares, apresentando impacto significativo na determinação do prognóstico do caso.

Conservative Treatment of Chronic Osteomyelitis Associated with Florid Osseous Dysplasia / Tratamiento Conservador de la Osteomielitis Crónica Asociada con Displasia Ósea Florida

ABSTRACT: Florid osseous dysplasia (FOD) is an extensive form of osseous dysplasia where normal trabecular bone is substituted by fibrous connective tissue and amorphous mineralized tissue. Usually, the lesions are mainly asymptomatic and the patients should be followed with clinical and imaging examination, requiring no intervention. Nevertheless, due to the poor vascularization of the lesion and to local trauma, secondary infections and osteomyelitis may occur. Patients may present with pain, mucosal ulceration, lesion exposure in the oral cavity, fistula and swelling. In such cases, the correct diagnosis and management of the lesion is decisive to reestablish patient's health and quality of life. The aim of this article is to present a case of complicating secondary chronic osteomyelitis treated successfully with conservative intervention. A 68-year-old black female patient reported a "swelling of the gums" that was present for eleven years, with episodes of periodic pain and swelling. On physical examination, a papule with suppuration in the alveolar mucosa in the right side of the mandible was observed. Panoramic radiography and CBCT showed a mixed lesion surrounded by sclerotic bone. The patient was diagnosed with chronic osteomyelitis in association with FOD and treated with antibiotic therapy together with surgical curettage. The incidence, etiophatology, differential diagnosis, treatment and prevention of secondary osteomyelitis associated with FOD are discussed in the light of literature. This information might assist the dentists while choosing the best treatment options for similar cases.

RESUMEN: La displasia ósea florida (DOF) es una forma de displasia ósea donde el hueso trabecular normal es sustituido por tejido conectivo fibroso y tejido mineralizado amorfo. En general, las lesiones son de origen asintomático y los pacientes deben ser seguidos con el examen clínico. Sin embargo, debido a la pobre vascularización de la lesión y al trauma local, pueden producirse lesiones secundarias y osteomielitis. Los pacientes pueden presentarse con dolor, ulceración mucosa, lesión de exposición en la cavidad oral, fístula y edema. En estos casos, el correcto diagnóstico y tratamiento de la lesión es decisivo para reestabilizar la salud y la calidad de la vida. El objetivo de este artículo consistió en presentar un caso de complicación secundaria crónica de osteomielitis tratados con tratamiento conservador. El paciente, negro, de 68 años de edad, consulta por "hinchazón de las encías" que se presentó durante once años, con episodios de dolor. En el examen intraoral, se observó una pápula con supuración en la mucosa alveolar en el lado derecho de la mandíbula. La radiografía panorámica y CBCT mostraron una lesión mixta rodeada de hueso esclerótico. El paciente fue diagnosticado con osteomielitis crónica en asociación con DOF y fue tratado con tratamiento antibiótico junto con curetaje quirúrgico. La incidencia, la etiopatología, el diagnóstico diferencial, el tratamiento y la prevención de la osteomielitis secundaria asociada con DOF se discuten a la luz de la literatura. Esta información puede ayudar a los dentistas a elegir las mejores opciones de tratamiento para casos similares.

Assessment of spontaneous resolution of idiopathic bone cavity

Abstract Idiopathic Bone Cavity (IBC) or Simple Bone Cyst (SBC) is a non- epithelialized bone cavity with serosanguinous fluid content or empty. There is a literature debate regarding its pathogenesis that remains unclear. The main treatment option is the surgical exploration, although there are successful cases described in the literature in which just a follow-up with clinical and radiographic evaluation was performed. Objective This study aimed to assess the spontaneous resolution of idiopathic bone cavity untreated by surgery. Material and Methods Twenty-one patients diagnosed with surgically untreated IBC were submitted to a follow-up protocol modified from Damante, Guerra, and Ferreira5 (2002). A clinical and radiographic evaluation was performed in 13 patients (13/21), while eight patients (8/21) were only radiographically evaluated. Three observers evaluated the panoramic radiographs of 21 patients and the Kappa test was performed by intra and inter-examiners. Inductive and descriptive statistics were applied to the results. Results Only one patient had a positive response to palpation and percussion of the teeth in the cyst area. Most of the cysts evaluated were rated as 3 (lesion "in involution"), 4 (lesion "almost completely resolved"), or 5 ("completely resolved"). Conclusions We observed progressive spontaneous resolution of IBC. Most cysts were found in the recovery process in different follow-up periods. Patient's follow-up, without surgery, may be considered after the diagnosis based on epidemiological, clinical, and radiographic features of the lesion.

Efeito da terapia de longa duração com ácido zoledrônico no osso esponjoso da mandíbula e fêmur de ratos Wistar / Effect of long-term zoledronic acid treatment on cancellous bone in the mandible and femur of Wistar rats

Os bisfosfonatos (BF) são amplamente utilizados no tratamento de doenças osteolíticas como metástases ósseas e osteoporose. A osteonecrose dos maxilares associada ao uso de BF (OMAB) é caracterizada pela presença de osso exposto ou que pode ser sondado através de uma fístula que persiste por mais de oito semanas em pacientes com história de terapia de BF e sem história de radioterapia na região de cabeça e pescoço e/ou sem doença metastática nos maxilares. A incidência de OMAB aumenta com a potência, duração do tratamento e dose de BF recebida. Até o presente momento, a fisiopatologia da OMAB não está clara, dificultando a prevenção e o tratamento. O objetivo deste estudo foi avaliar o efeito da administração de altas doses Ácido Zoledrônico (AZ) por período prolongado no osso esponjoso da mandíbula e da metáfise proximal do fêmur de ratos Wistar. Para relacionar as descobertas à fisiopatologia da OMAB, o regime de administração de BF de um modelo animal relevante desta lesão foi reproduzido. Seis animais receberam AZ (0,6 mg / kg) e seis receberam solução salina no mesmo volume (Controles). Os compostos foram administrados por via intraperitoneal em cinco doses a cada 28 dias. A eutanásia dos animais ocorreu após 150 dias de início da terapia. As hemimandíbulas e fêmures direitos foram escaneados usando Micro-tomografia computadorizada (Micro-CT) de alta resolução (14 m). Para a primeira análise realizada neste estudo, os dados morfométricos do osso esponjoso foram calculados na região do segundo e primeiro molar na mandíbula e na metáfise do fêmur usando CTAnalyzer (Bruker, Bélgica). Para a segunda análise, cinco amostras de hemimandíbulas de cada grupo foram cortadas em lâminas histológicas (5 m) e coradas com Hematoxilina e Eosina. Para comparar os parâmetros morfométricos na Micro-CT e histologia, as imagens de Micro-CT foram espacialmente alinhadas à histologia. Os dados morfométricos do osso alveolar foram calculados usando o software CTAnalyzer (Bruker, Bélgica) na região entre as raízes mesial e distal do primeiro molar. A densidade da área vascular (área vascular/área total; VA/TA) e os dados histomorfométricos ósseos foram estimados usando Axiovision na mesma região (entre as raízes mesial e distal do primeiro molar). Foi adotada significância estatística de 5% ( = 0,05). Os animais tratados com AZ apresentaram aumento significativo na porcentagem de volume ósseo (p <0,05) com trabéculas mais espessas, osso mais compacto com menor separação trabecular na mandíbula e no fêmur. Na mandíbula, o aumento da densidade óssea e diminuição da separação trabecular foram fortemente correlacionados com a diminuição da área vascular observada no grupo AZ (p <0,05). Em conclusão, o tratamento de longa duração com altas doses de AZ foi significativamente associado ao aumento na densidade óssea e à diminuição dos espaços medulares, canais nutritivos e vasculatura do osso alveolar. A análise com Micro-CT revelou alterações semelhantes na estrutura óssea tanto na mandíbula quanto no fêmur do grupo AZ.(AU)

Bisphosphonates (BFs) are widely used in the treatment of osteolytic diseases such as bone metastases and osteoporosis. The osteonecrosis of the jaws related to BF (ONB) is characterized by the presence of exposed bone or bone that can be probed through a fistula that persists for more than eight weeks in patients with a history of BF therapy and without history of head and neck radiotherapy and / or without metastatic disease in the jaws. The incidence of ONB increases with potency, duration of treatment and dose of BF received. Thus far, the pathophysiology of ONB is unclear, hampering prevention and treatment. The aim of this study was to objectively assess the effect of long-term high-dose Zoledronic Acid (ZA) on cancellous bone in the jaw and femur of Wistar rats. In order to link our findings to the physiopathology of ONB, the therapeutic regiment of a relevant ONB animal model was reproduced. Twelve Wistar rats were randomly divided in two groups: six received Zoledronic acid (ZA; 0.6 mg / kg) and six (Controls) received saline solution in the same volume. The compounds were administrated intraperitoneally in five doses each 28 days. The rats were killed after 150 days of the therapy onset. Mandibles and femurs were scanned using a high-resolution (14m) micro-computerized tomography (Micro-CT). For the first analysis carried in this study, cancellous bone morphometric data were calculates in the region of the second and first molar in the mandible and in the proximal femur using CTAnalyzer (Bruker, Belgium). For the second analysis five samples were cut into histological slices (5m) and stained with Hematoxylin and Eosin. In order to compare the same morphological structures in Micro-CT and histology, the Micro-CT images were aligned to histology. Alveolar bone morphometric data (Micro-CT) was calculated using CTAnalyzer (Bruker, Belgium) in the region between the mesial and distal roots of the first molar. Blood vessels density and bone histomorphometric data were calculated using Axiovision (Carl Zeiss, Germany) in the same region used for Micro-CT evaluation. Statistical significance of 5% (=0.05) was adopted. ZA treated rats presented significant increase in the percentage of bone volume (p<0.05) with thicker trabeculae and more compact bone with smaller marrow spaces in the mandible and femur. In the mandible, the increase in bone density and decrease of marrow spaces size was strongly correlated with the decrease in the vascular area noticed in the ZA group (p<0.05). In conclusion, long-term high-dose ZA treatment was significant associated with the increase of bone density and the diminution of medullary spaces and nutritive canals size as well as decrease in vascularity of the alveolar bone. Micro-CT investigation showed similar changes in bone structure in the mandible and femur in the ZA group.(AU)