The relation between Schneiderian membrane thickening and radiodiagnostic features of periapical pathology

Abstract This study aimed to assess the relationship between Schneiderian membrane thickening and periapical pathology in a retrospective analysis of Cone Beam Computed Tomography (CBCT) images. For this, 147 CBCT scans containing 258 sinuses and 1,181 teeth were assessed. Discontinuation of the lamina dura, widening of the periodontal ligament space, apical periodontitis (AP), and partly demineralized maxillary sinus floor associated with AP were considered periapical pathology. Maxillary sinus mucosal thickening (MSMT) was classified as odontogenic or non-odontogenic. An irregular band with a focal tooth associated thickening and local thickening related to a root were considered odontogenic types of MSMT. The relation between the imaging features of periapical pathology and the type and thickness of MSMT was determined by logistic regression and linear mixed model, respectively. In addition, linear regression and Mann Whitney test evaluated the relation and demineralization of the AP lesion towards the sinus floor (p≤0.05). The odds of having an odontogenic type of MSMT were significantly higher when a periapical pathology was present in the maxillary sinus. Eighty-two percent of AP partly demineralized towards the sinus floor were associated with an odontogenic MSMT. Both AP lesions partly demineralized towards the sinus floor and, with increased diameter, led to increased MSMT. In conclusion, there is an 82% risk of having an odontogenic type of MSMT with the presence of AP partly demineralized towards the sinus floor. More thickening of the maxillary sinus mucosa is seen with larger AP lesions and partial demineralization of the sinus floor.

Resumo O objetivo deste estudo foi avaliar a relação entre o espessamento da membrana Schneideriana e periapicopatia em uma análise retrospectiva de imagens de Tomografia Computadorizada de Feixe Cônico (TCFC). Para isso, foram avaliadas 147 imagens de TCFC, contendo 258 seios maxilares e 1.181 dentes. A descontinuação da lâmina dura, o aumento do espaço do ligamento periodontal, a periodontite apical (PA) e o assoalho do seio maxilar parcialmente desmineralizado associado à PA foram considerados sinais de periapicopatia. O espessamento da mucosa do seio maxilar foi classificado como odontogênico ou não-odontogênico. Uma faixa irregular com um dente focal associado ao espessamento e espessamento local em relação a uma raiz foram considerados como tipos odontogênicos de espessamento da mucosa do seio maxilar. A relação entre a periapicopatia e o tipo de espessamento da mucosa do seio maxilar foi determinada (p≤0.05). A probabilidade de se ter um tipo odontogênico de espessamento da mucosa do seio maxilar foram significativamente maiores quando uma periapicopatia estava presente no seio maxilar. Oitenta e dois por cento da PA parcialmente desmineralizada em direção ao assoalho do seio estavam associados a um espessamento odontogênico da mucosa do seio maxilar. Ambas as lesões de PA parcialmente desmineralizadas em direção ao assoalho do seio e com aumento do diâmetro levaram a um aumento do espessamento da mucosa do seio maxilar. Em conclusão, com a presença de periapicopatia, há um risco maior de ter um tipo odontogênico de espessamento da mucosa do seio maxilar. Um espessamento maior da mucosa do seio maxilar é observado com lesões de PA maiores e desmineralização parcial do assoalho do seio maxilar.

How does nano-focus computed tomography impact the quantification of debris within the root canal system?

Abstract The aim of this study was to compare the quantification of hard-tissue debris by using micro-computed tomography (micro-CT) and nano-focus computed tomography (nano-CT) after root canal instrumentation. Ten mandibular molars containing an isthmus in the mesial root were scanned in a SkyScan 1172 micro-CT device with a voxel size of 12.8 µm and in a NanoTom nano-CT device with 5.5 µm. The mesial root canals were irrigated with 5 mL of saline solution at the orifice level, instrumented with Reciproc R25 files and a second scanning was performed by micro-CT and nano-CT devices for post-instrumentation images. DataViewer software was used for registering the pre- and post-operative micro-CT and nano-CT images. The root canal and the debris were segmented for quantitative analysis of the volume of the canal and volume of debris using CTAn software. Statistical analysis was performed using the T test for comparison between volume of the canal after instrumentation and volume of debris in both image modalities. The level of significance was set at p < 0.05. Nano-CT images showed higher values of debris when compared with micro-CT (p < 0.05) after root canal instrumentation. No difference was observed between the volume of the root canal after instrumentation in the two imaging methods used (p > 0.05). Nano-CT technology can be recommended as a more precise method for quantitative analysis of hard-tissue debris. Moreover, in Endodontic research it is a promising method, as it is capable of providing higher spatial and contrast resolution, faster scanning and higher image quality.