Archives - Page 2

• Revue illustrée des principales indications de CBCT en orthodontie.

  Vol. 12 No 1 (2020)

  Cette revue illustrée porte sur les principales indications actuellement recommandées dans la littérature d’utilisation du cone beam computed tomography (CBCT) en orthodontie. Il s’agit des anomalies dentaires, des canines incluses, des dents surnuméraires, des troubles de l’éruption et des résorptions radiculaires externes liées aux traitements orthodontiques. L’examen CBCT doit être justifié individuellement, au cas par cas, et de pouvoir apporter un bénéfice au patient en terme de diagnostic et/ou de traitement orthodontique. L’orthodontiste prescripteur doit être capable d’interpréter et est responsable de l’interprétation de tout ce qui est visible sur l’ensemble du champs de vue du CBCT.

• Artifacts related to cone beam computed tomography (CBCT) technology and their significance for clinicians: illustrated review of medical literature.

  Vol. 11 No 1 (2020)

  Objective: to explain the meaning and to illustrate technical artifacts (aliasing as well as the ring artifact) and beam hardening (metal artifact) that can be present in the dentomaxillofacial cone beam computed tomography (CBCT), and to check the accessibility of free illustrations of these artifacts in medical publications.

  Material and methods: One observer applied five search equations using database PubMed. The exclusion criteria were: experimental studies, animal studies, studies not related to dentomaxillofacial area, and articles with closed access. There was no time limit for the search of articles. We limited our search to English and French language.

  Results: Only 3 articles out of 434 publications were retained after application of inclusion/exclusion criteria. In these articles only 4 annotated figures were freely accessible in medical publications from PubMed.

  In this paper we presented examples of aliasing, ring artifact, and beam artifacts from I-CAT, Carestream 9000 3D (Kodak), and Planmeca Promax 3D Mid CBCT. The intensity of beam hardening artifact varies from major degradation of image (i.e., subperiosteal implants, bridges, crowns, dental implants, and orthodontic fix appliances), through mean degradation (screws securing titanium mesh, head of mini-implant) to no beam hardening on metallic devices (orthodontic anchorage, orthodontic contention wire) or on dense objects (endodontic treatments, impression materials, Lego box). Some beam hardening artifacts arising from nasal piercing, hairs, or hearing aid device may be present on the image but they will not disturb the evaluation of the field of view.

  Conclusions: reduction of aliasing artifact is related with the improvement of detectors quality. The presence of ring artifact means that CBCT device has lost its calibration. The field of view (FOV) needs to be reduce in order to avoid scanning regions susceptible to beam hardening (e.g., metallic restorations, dental implants). Finally, the accessibility to open knowledge on technique -related CBCT artifacts seems extremely limited when searching at PubMed database.

• Accessibility to the knowledge on anatomical variations from dentomaxillofacial CBCT

  Vol. 10 No 1 (2020)

  Objective: to investigate the accessibility of open access article on anatomical variations described on cone beam computed tomography (CBCT) using PubMed database. We wanted to investigate how many journals are sharing articles without pay-wall and how many are sharing articles without author publication charges.

  Material and methods: a search equation was designed with exclusion criteria limiting the search in PubMed to articles published in English and French. The search was performed by one observer. We had found 2228 articles; among them 709 were accessible as ‘full text’. After applying exclusion criteria and after full text reading only 50 articles remained for the review.

  Results: the 50 selected articles shared 306 annotated (visual marking, explanation like arrows) and 432 not annotated figures with the public. The 76% of articles were single studies on one specific topic. The main topic was endodontics with 22 articles. 28 journals from all continents participated in the effort of sharing of figures on anatomical variations from CBCT. However, only 2 journals were completely free of charges for authors and readers.

  Conclusions: we have found only 15 annotated and 3 not annotated figures in 2 articles published in 2 different open access journals (without reader pay-wall and without author publication charges). Sharing the knowledge on anatomical variations from dentomaxillofacial CBCT represents an exception in dental literature.

• Computed tomography of the heads of ancient Egyptian mummies: a systematic review of the medical literature

  Vol. 9 No 1 (2020)

  Objective: To summarize the current knowledge on CT scanning of Egyptian mummy heads and faces and provide more valid methodology than that previously available.

  Material and methods: A systematic review was performed by one observer using two biomedical databases: PubMed and EMBASE. Inclusion and exclusion criteria were applied along with language restrictions. Finally, 2120 articles were found, 359 articles were duplicated among all search equations, 1454 articles were excluded, 307 articles were retained for full review, and 28 articles (31 mummies) were selected for the final study (PRISMA workflow).

  Results: The data were categorized into the following groups: 1) general information; 2) 1^st author affiliation; 3) CT radiological protocol; 4) excerebration pathways; 5) soft tissue preservation; 6) dental status and displaced teeth; 7) packing of the mouth, ears, nose, and eyes, and 8) outer facial appearance. The evidence-based quality of the studies was low because only case reports and small case series were found.

  Discussion: The embalming art applied to a mummified head and face shows great variability across the whole span of Egyptian civilization. The differences among the various embalming techniques rely on multiple tiny details that are revealed by meticulous analysis of CT scans by a multidisciplinary team of experts.

  Conclusion: There is a need for more systematization of the CT radiological protocol and the description of Egyptian mumm’y heads and faces to better understand the details of embalming methods.

• Complications in surgically assisted rapid maxillary expansion: a systematic review of the medical literature.

  Vol. 8 No 1 (2019)

  Our aim was to perform a systematic open-access review of various complications reported for surgically assisted rapid maxillary expansion (SARME) procedures. There were 37 articles found in Pubmed using the search equation. Twelve articles were initially excluded according to the exclusion criteria. The 25 remaining articles were read in full for their descriptions of complications related to the SARME procedure in mature patients. The main reversible complications of SARME were infection, postoperative pain, and bleeding. There were also complications related to distractors, to secondary surgeries, and pterygomaxillary junction. The main non-reversible complications of SARME were associated with teeth, periodontal bone loss, and skull base fractures. Large field-of-view cone beam computed tomography (maxilla and skull base) should be implemented as initial planning tool to prevent many potential complications. The current trend for “minimally invasive” surgery in SARME might be, from an ethical point of view, transformed onto “minimally complicated” surgery as complication is still more harmful for any given patient than any potential perioperative surgical invasiveness.

   

• Troubles oro-faciaux dans Fibrodysplasia ossificans progressiva. Revue systématique.

  Vol. 7 No 1 (2019)

  La fibrodysplasia ossificans progressiva ou myosite ossifiante est une maladie autosomique dominante très rare. La maladie est caractérisée par l’apparition progressive de calcifications ectopiques dans les tendons, les muscles striés, les ligaments et les fascias. Elles entrainent une perte de mobilité progressive du corps allant jusqu’à un handicap physique sévère. Le présent travail est une revue systématique de la littérature concernant les aspects oro-faciaux de cette pathologie rare. Des pistes de prise en charge de ces patients au niveau dentaire et maxillo-facial sont aussi proposées.

• Myosite ossifiante du muscle temporal après polytraumatisme

  Vol. 6 No 1 (2019)

  La myosite ossifiante traumatique (MOT) du muscle temporal est une pathologie extrêmement rare. Une limitation de l’ouverture buccale est le symptôme clé. Les examens d’imagerie sont très utiles au diagnostic, le CT-scanner de la face étant l’examen le plus performant pour la détection de la MOT. Le meilleur traitement est la résection chirurgicale complète. Les cas de myosite ossifiante traumatique dans la région de la tête et du cou sont rares. Les atteintes au niveau du muscle temporal sont encore plus rares. Nous présentons ici le cas d’une ossification isolée du muscle temporal gauche après un polytraumatisme. L’intérêt de l’observation clinique du cas présenté est donc de documenter la littérature. Le diagnostic différentiel et les signes pathognomoniques présents sur les examens d’imagerie seront également détaillés.

• Quality assessment of instructions for authors in dental, oral and maxillofacial journals

  Vol. 5 No 1 (2019)

  Objective: to develop and test inter-observer reproducibility of instructions for authors quality rating (IAQR) tool measuring the quality of instructions for authors at journal level for a possible improvement of editorial guidelines. 
  Material and methods: instructions for authors of 75 dental and maxillofacial surgery journals were assessed by two independent observers using assessment tool inspired from AGREE with 16 questions and 1 to 4 points scale per answer. Two observers evaluated the instructions of authors independently and blind to impact factor of a given journal. Scores obtained from our tool were compared 
  with “journal impact factor 2013”. 
  Results: IAQR presented with an excellent interobserver reproducibility (κ= 0.81) despite a difference in data distribution between observers. There existed a weak positive correlation between IAQR and “journal impact factor 2013”. 
  Conclusions: The IAQR is a reproducible quality assessment tool at the journal level. The IAQR assess the quality of instruction for authors and it is a good starting point for possible improvements of the instructions for authors, especially when it comes to their completeness. 
  Nemesis relevance: 28% of dental and maxillofacial journals might revise their instructions for authors to provide more up-to-date version.

• Paget’s disease of bone, biphosphonates and jaw osteonecrosis: a case report

  Vol. 4 No 1 (2019)

  Objective: Paget’s disease of bone is characterized by a focal increase in bone

  resorption and accelerated bone formation leading to a weaker and disorganised bone. Bisphosphonates (BPs) have been the treatment of choice of Paget’s disease since the 1990s. Medication related osteonecrosis of the jaw (MRONJ) is a rare event in non oncologic patients. We describe a rare case of  Paget’s disease

  involving the maxilla with osteonecrosis in a context of bisphosphonate treatment.

   

  Case report: an 87-year-old woman presented with 4 episodes of bone necrosis in 15 years. In this case report there is a clear chronologic association between the occurrence of MRONJ and the administration of iv BP for Paget’s disease.

  Maxillofacial involvement of Paget’s disease occurs in less than 15% of cases. There is a lack of information in the literature about the association of MRONJ and Paget’s disease. Even if osteonecrosis of the jaw could be a consequence of the

  disease, in this case, it is more in relation to the BP treatment.

   

  Conclusions: Although MRONJ might be considered a rare condition in Paget’s disease, patients prior to starting antiresorptive therapy and in particular iv BPs should have a complete dental examination and panoramic X-Ray.

   

  Nemesis relevance: side effect of bisphosphonate treatment

   

• 

  Cytotoxicité des modèles tridimensionnels en papier issus d'imprimante tridimensionnelle

  Vol. 3 No 1 (2018)

  Objective: Our study aimed to determine the possibility of using models created with a low-cost, paper based 3D printer in an operating room. Therefore influence of different methods of sterilization on models was tested and cytotoxicity of generated models was determined.

  Material and methods: 30 cuboids divided into three groups were used for verification of shape stability after sterilization. Each group was sterilized either with: Ethylene oxide in temperature 55˚C, Hydrogen peroxide gas plasma in temperature 60˚C or Gamma irradiation at 21˚C, 25kGy. Each cuboid was measured using calliper three times before and three times after sterilization. Results were analysed statistically in Statgraphics Plus. Statistical significance was determined as p< 0.05. Sixty cylinders divided into six groups were used for cytotoxicity tests. Three of those groups were covered before sterilization with 2-octyl-cyanoacrylate. Each group was sterilized with one of the previously described methods. Cytotoxicity was tested by Nanostructural and Molecular Biophysics Laboratory in Technopark Lodz using normal adult human dermal fibroblasts. Survival of cells was tested using spectrophotometry with XTT and was defined as ratio of absorbency of tested probe to absorbency of control probe. Calcein/Ethidium dyeing test was performed according to LIVE/DEAD Viability/Cytotoxicity Kit protocol. Observation was done under Olympus GX71 fluorescence microscope. Results: There was no statistically significant difference for established statistical significance p=0.05 in cuboids dimensions before and after sterilization regardless of sterilization method. In XTT analysis all samples showed higher cytotoxicity against normal, human, adult dermal fibroblast culture when compared to positive control. ANOVA statistical analysis confirmed that 2-octyl cyanoacrylate coating of paper model improved biological behaviour of the material. It decreased cytotoxicity of the model independently of sterilization method. In calcein/ethidium dyeing test due to the high fluorescence of the background caused by cylinders of analysed substance it was impossible to perform the exact analysis of the number of marked cells.

  Conclusions: Acquired results allow to conclude that Mcor Technology Matrix 300 3D paper-based models can be used in operating room only if covered with cyanoacrylate tissue adhesive.

  Nemesis relevance: no statistically significant difference in cuboids dimensions before and after sterilization regardless of sterilization method. Presence of high cytotoxicity of 3D paper-based models without coating.

• Three-dimensional analysis of airway space and mandibular morphology in Pierre Robin sequence using cone beam computed tomography.

  Vol. 2 No 1 (2018)

  Objectives: The Pierre Robin sequence (PRS) is defined by retromicrognathia, glossoptosis, and sleep apnea and can also be associated with cleft palate. Diagnosis, management and mandibular catch-up growth are still controversial issues in PRS patients. The aim of our retrospective study was to evaluate in three dimensions (3D) the airway space and mandibular morphology in PRS compared to a normal control group patients in the pre-orthodontic period of life. The null hypothesis was that we would not find a significant difference between the PRS and control group patients in oropharyngeal airway volume measurements. Material and methods: We analyzed 9 PRS patients (mean age: 8 years-old) who underwent cleft palate surgery in the first four months of life, performed by the same surgeon using the same technique. Cone-beam computed tomography (CBCT) was performed in these patients after local ethical committee approval. The control group consisted of 15 patients (mean age: 9 years-old) with CBCT already performed for other reasons. 3D Slicer was used in both groups for semi-automatic segmentation of the airway space. Two independent observers performed semi-automatic segmentations twice in each patient with a one- week interval between the two series of measurements. Airway volume was automatically measured using 3D Slicer. We also developed a 3D cephalometric analysis with Maxilim software in order to define a 3D mandibular morphology which consisted of 25 landmarks, 4 planes, and 23 distances. Two independent observers performed the 3D cephalometric analysis twice for each patient, with a one- week interval between the two series of measurements. Results: There was no significant difference in the intra- and inter-observer measurements between the PRS and control groups for airway space volume (p<0.05). However, there was a significant difference in the shape of the mandible between the PRS group and the control group (p<0.05). Conclusions: Vertical ramus width and mandibular global anteroposterior length were significantly lower in the PRS group. Mandibular hypoplasia could be found in PRS patients not only in the horizontal dimension. Nemesis relevance: the null hypothesis was confirmed. Moreover we failed to find exactly the same control group under 9 years-old due to radioprotection restrictions of application of cone beam CT in children.

• Pathologies osseuses des maxillaires récidivantes

  Vol. 1 No 1 (2018)

  Plusieurs pathologies osseuses des maxillaires ont comme caractéristique une tendance à la récidive, et ce même après un traitement approprié. Il convient donc de les reconnaître afin de pouvoir les surveiller, à la fois cliniquement et par une technique d’imagerie appropriée. On distinguera ici des pathologies tumorales bénignes et malignes, métaboliques, malformatives et infectieuses. Actuellement, le CT scan est la technique d’imagerie médicale de premier choix pour établir le diagnostic différentiel et permettre la surveillance de ces pathologies osseuses. Le traitement de ces pathologies récidivantes est soit le curetage/énucléation si possible (corticales non rompues) soit une résection interruptrice ou non des maxillaires ou de la mandibule, et ce en fonction des données cliniques et surtout anatomopathologiques à discuter et envisager au cas par cas, la généralisation dans ce domaine étant impossible voire dangereuse pour le patient. Il ne peut donc être question de proposer des recommandations ni des algorithmes décisionnels. Mots clés: pathologies osseuses, récidive, maxillaire, mandibule