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Paper 4
Published in Amanda Rabone, Benedict Thomson, Nicky Dineen, Vincent Helyar, Aidan Shaw, The Final FRCR, 2020
Amanda Rabone, Benedict Thomson, Nicky Dineen, Vincent Helyar, Aidan Shaw
A 42 year old patient is referred for imaging by his GP with a painless lump on his jaw. A radiograph demonstrates a lucent lesion at the mandibular ramus. This has a multilocular honeycomb-like appearance. It is well defined and corticated. There is evidence of root resorption affecting the adjacent teeth. An MRI reveals a lesion containing cystic and soft tissue signal elements. There are no fluid-fluid levels. The septations and solid components enhance avidly following contrast injection.
Cysts and Tumours of the Bony Facial Skeleton
Published in John C Watkinson, Raymond W Clarke, Terry M Jones, Vinidh Paleri, Nicholas White, Tim Woolford, Head & Neck Surgery Plastic Surgery, 2018
Julia A. Woolgar, Gillian L. Hall
Unicystic ameloblastomas (UAs)52 account for 5–15% of all ameloblastomas.55 The term should be reserved for well-defined, monocystic lesions with a lining focally composed of ameloblastomatous epithelium (type I, luminal UA). The inner surface of the cyst lumen may show one or more polypoid, pedunculated masses (type II, intraluminal UA) or intramural nodular growths (type III, intramural UA). Types I and II tend to be in a dentigerous relationship although on removal, the involved tooth is displaced by the cyst rather than projecting into the lumen. Pathogenesis is controversial, theories including an origin from a pre-existing odontogenic cyst, ameloblastic transformation of reduced enamel epithelium, and cystic degeneration and subsequent fusion of microcysts within a SMA. The posterior mandible is the most common site (maxilla: mandible ratio, 1:5). Teens and young adults are mainly affected without an obvious gender distribution. Usual presentation is a painless swelling. Radiographically, UA may be unilocular or multilocular. Root resorption is common. Diagnosis requires assessment of the complete cyst and categorization based on findings in both the epithelial cyst lining and fibrous cyst wall. Types I and II are usually treated conservatively by enucleation and curettage. Type III shows a greater tendency to recur and is generally managed as SMA.
Surgical endodontics
Published in John Dudley Langdon, Mohan Francis Patel, Robert Andrew Ord, Peter Brennan, Operative Oral and Maxillofacial Surgery, 2017
Once the flap is raised and the root is visualized, it may become apparent that the tooth is non-salvageable. Likely causes include root fracture, palatal perforation, lateral canal inaccessible to surgery or root resorption.
Investigation of effective intrusion and extrusion force for maxillary canine using finite element analysis
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2019
Jianlei Wu, Yunfeng Liu, Dongcai Wang, Jianxing Zhang, Xingtao Dong, Xianfeng Jiang, Xu Xu
The effective interval of canine intrusive force was enhanced almost twice as that observed in our previous study of 38–40 g (Wu et al. 2018); it was mainly because effective tensile stress and compressive stress ranges were not the same. The biomechanical responses of bone cells showing unequal sensitivity to tensile and compressive stresses were more convincing in orthodontics (Han et al. 2005). Illustratively, the effective intrusive force of 80–90 g was extremely close to the frequently used clinical orthodontic force of 100 g (Wahab et al. 2011). Moreover, according to Han et al. (2005), the percentage of root resorption was as low as 5.78 ± 3.86% when an objective tooth suffered an intrusive force of 100 g; this clinical study further corroborated the results of the current study.
Orthodontic management of a non-vital immature tooth treated with regenerative endodontics: a case report
Published in Journal of Orthodontics, 2018
Zynab Jawad, Claire Bates, Mandeep Duggal, Hani Nazzal
Orthodontic movement of traumatised teeth is challenging with some reported mid/post treatment unwarranted adverse effects (Kindelan et al. 2008; Duggal et al. 2015). With regards to pulp vitality, it remains inconclusive whether orthodontic tooth movement of traumatised teeth increases the risk of pulp necrosis above that of uninjured teeth undergoing tooth movement (Duggal et al. 2015; Kindelan et al. 2008). Root resorption is a known risk factor with orthodontic treatment (Malmgren et al. 1982). Retrospective studies examining resorption in traumatised teeth are also inconclusive as they are based on small patient numbers and a heterogeneous collection of injuries, orthodontic appliances and operators (Malmgren et al. 1982; Brin et al. 1991). Pre orthodontic root resorption, as a result of dental trauma, is associated with a higher risk of increased root resorption as a result of orthodontic forces (Levander and Malmgren 1988). Therefore, detailed clinical and radiographic assessment is therefore paramount prior to orthodontic treatment.
Continued professional development
Published in Journal of Orthodontics, 2018
This case report describes the unusual incident of bilateral resorption of his maxillary first permanent molars by the unerupted second molars. Mild root resorption due to orthodontic treatment commonly causes the following: Loss of permanent teethExtreme discomfort due to mobilityRadiographic shortening of the rootsPulpal symptoms of affected teeth; orContinued root resorption once orthodontic treatment is complete