Enhnced CPD DO C Thmesh Keri Kndsmy Gnesn Are Chnges in Specific Lndmrk Antomy on Pnormic Imge Suggestive of Mxillry Sinus Disese? Astrct: Dentl pnormic rdiogrphy is commonly employed investigtion in dentistry, however, its use in the primry indiction of mxillry sinus disese is often underestimted. Being le to identify nomlies or normlities involving the mxillry sinus on rdiogrphs will fcilitte erly intervention nd pproprite referrl to the relevnt specilties. CPD/Clinicl Relevnce: Dentists should hve good understnding of rdiogrphic ntomy of the mxillry sinus. Recognizing rdiogrphic chnges llows pproprite referrl nd improved ptient cre. Dent Updte 2018; 45: 977 984 Due to their ntomicl loction, the mxillry sinuses should e ssessed when estlishing dignosis for orofcil pin nd ny diseses relting to upper teeth. 1 Dentists should e le to interpret conventionl pnormic rdiogrphy, including hving good knowledge of norml ntomy nd its vrints. For generl dentl prctitioners (GDPs), pnormic rdiogrphy is widely ccessile nd is common rdiogrphic technique used in ssessing pthosis, prticulrly of lrger lesions not fully imged y intr-orl rdiogrphy. Dentists re thought to prescrie Thmesh Keri, BDS(Hons) MFDS RCSEd, Dentl Core Trinee in Orl nd Mxillofcil Surgery nd Kndsmy Gnesn, BDS, MDS(OMFS), MFDS RCS(Eng), FFD RCSI (Orl Surg Orl Med), Consultnt in Orl Surgery, Orl nd Mxillofcil Surgery Deprtment, Southend University Hospitl, Essex SS0 0RY, UK. 2.7 million pnormic rdiogrphs per yer in the UK, nd they will often e the first to identify coincidentl findings of mxillry sinus disese. 2 Being le to distinguish etween dentl nd mxillry sinus symptoms enles the dentist to determine when dentl tretment is pproprite nd when referrl to different specilty is more pt. Similrly, eing le to interpret dentl rdiogrphs systemticlly will enle the dentist to identify oth dentl nd sinus pthology competently. Extensive lesions occupying the mxillry sinus cn often produce surprisingly few clinicl fetures. Therefore, pnormic rdiogrphs cn frequently e used to indicte the presence of mxillry sinus disese. 3 There is wide vriety of pthologicl conditions tht ffects the mxillry sinuses (Tle 1). These cn e ctegorized into those tht originte from the sinus epithelium, the djcent prnsl sinuses, nsl cvity, dentl tissues, or in the djcent ony structures with expnsion into mxillry ntrum. 2 Specificlly, extrinsic cysts of odontogenic origin will e the focus of this rticle. One should lso consider developmentl nd ntomicl vritions, which my present s flse-positive rdiogrphic chnge of disese. Lndmrks in the mxillry sinus re on pnormic imge Rdiologicl ssessment of the mxillry sinuses requires thorough exmintion, including the degree of ertion nd ltertion of the ony outlines of the mxillry sinuses. There re three key ntomicl rdio-opque lines visile on pnormic rdiogrph, which should e crefully trced when detecting disese ssocited with the mxillry sinus. Two further lines should lso e cknowledged, tht is those of the hrd plte nd the floor of the mxillry ntrum. However, these would only e distorted in extensive lesions which perforte these wlls nd, therefore, they would e cliniclly plple. The three lines re: 1. The nteromedil wll of the mxillry ntrum; Novemer 2018 DentlUpdte 977
Pthologicl nd developmentl conditions ffecting the mxillry sinuses which present with rdiogrphic chnges Exmples Inflmmtory Trum Neoplsms Acute nd chronic sinusitis Hemtom Adenocrcinom Amelolstom Clcifiction Developmentl conditions Other one normlities Anthrolith Firous dysplsi Pget's disese of one Intrinsic Mucous (or mucosl) retention cyst Cysts Odontogenic Developmentl Odontogenic Kertocyst Dentigerous cyst Extrinsic Inflmmtory Rdiculr cyst Non-odontogenic Nsopltine cyst Tle 1. Exmples of pthologicl nd developmentl conditions tht ffect the mxillry sinuses. The list of exmples is y no mens exhustive ut the effects of odontogenic cysts re demonstrted in this rticle. Figure 1. A stndrd pnormic rdiogrph with the key hrd tissue shdows ssocited with the right mxillry sinus outlined. A line digrm represents these lndmrks more clerly. 1) Pterygomxillry fissure; 2) zygomtic uttress; 3) nteromedil wll of the mxillry ntrum. The hrd plte (red rrow) nd floor of the mxillry ntrum (yellow rrow) should lso e considered. 2. The pterygomxillry fissure; 3. The zygomtic uttress. These ntomicl hrd tissue shdows cn e illustrted on stndrd pnormic rdiogrph (Figure 1). The pterygomxillry fissure is medil to the temporl foss nd is ounded y the pterygoid process of the sphenoid one (superiorly), pterygoid plte of the sphenoid one (inferiorly) nd the posterior wll of the mxillry sinus (nteriorly). This lndmrk ppers s terdrop-shped shdow (Figure 2). The zygomtic processes of the mxill re thick uttresses of one, which extend lterlly from the mxill nd pper s J-shped or hockey stick shdows superimposed over the mxillry sinuses (Figure 2). The nteromedil wll of the mxillry ntrum is composed of the lterl wll of the nsl cvity nd the fcil surfce of the superior mxill (Figure 2). Interpreting mxillry sinus disese on two-dimensionl (2-D) imges versus visulizing mxillry sinus disese on threedimensionl (3-D) imges The sence of ny of the rel hrd tissue shdows shown in Figure 1 my indicte the presence nd extent of sinus disese (Figures 3 8). This rticle presents series of clinicl cses in which dento-lveolr lesion ws suspected on pnormic rdiogrph nd referrl to n orl surgery specilist ws mde for further investigtion. By considering these chnges on pnormic rdiogrphy (Figure 1), long with clinicl history nd exmintion, further rdiogrphic investigtion, such s computed tomogrphy (CT) or cone-em computed tomogrphy (CBCT), ws performed if it ws deemed pproprite. In the mjority of cses, 2-D imging does not llow visuliztion of 978 DentlUpdte Novemer 2018
Figure 2. These three lines cn e represented on the lterl nd frontl views of the skull. The frontl process of the mxill (green surfce) nd lterl nsl wll compose the nteromedil wll of the mxillry sinus (red line). The zygomtic uttress (white line) is locted in the region of the zygomtic process of the mxill. The reltive position of the pterygomxillry fissure is mrked s the lue line. Figure 3. (, ) A 41-yer-old femle presented with one-yer history of recurrent left-sided fcil pin. A CT scn reveled lrge cyst ssocited with n ectopic left mxillry third molr. The cyst occupied lmost the entire mxillry sinus nd extended into the left lterl nsl foss. Note the loss of the hrd tissue shdows of the lterl nsl wll, zygomtic uttress nd pterygomxillry fissure on the pnormic rdiogrph. Histopthology results following enucletion confirm the lesion s dentigerous cyst. the size of the disese process, its effects on surrounding structures nd its composition. Therefore, 3-D imging is often required to complement the primry investigtions. 4 Discussion Although there re cler rdiogrphic chnges visile on pnormic rdiogrphy, there is no indiction s to the extent of the disese. Despite the ovious dvntges of low rdition dose nd lrge visuliztion of the fcil ones, their use is limited for numer of resons. 4 Pnormic rdiogrphs re unrelile in comprehensively confirming the sence or presence of disese owing to the superimposition of soft tissue, ir nd rtefctul shdows which cn overlie the required hrd tissue structures. Furthermore, pnormic imges re prone to distortion, prticulrly due to positioning errors. 1 In ddition, if pnormic rdiogrph ppers norml, then it does not necessrily indicte tht there is no disese present (flse-negtive findings). However, the clinicin should e le to pprecite tht oth clinicl symptoms nd rdiogrphic chnges my signify tht further investigtions re required, usully in the form of 3-D rdiogrphic imging. Approprite referrl for dvnced imging in secondry or tertiry cre setting should comply with Ionizing Rdition (Medicl Exposure) Regultions (IR(ME)R) 2000. 5 If n normlity is identified on pnormic rdiogrph, either y GDP or nother specilty, then referrl to n pproprite specilist should e mde. At this stge, the specilist my consider dvnced imging, such s CBCT or conventionl CT scn, to ssist with ptient mngement or tretment. There hve een vrious studies tht hve compred the use of 2-D nd 3-D rdiogrphic imging in evluting the mxillry sinuses. Tdind et l showed tht, lthough oth pnormic rdiogrphs nd CBCT showed high sensitivity for identifying mxillry sinus pthology, CBCT showed considerly higher specificity. 6 In ddition, their findings indicte tht there is merely 1 in 2 success rte in the detection of pthology y pnormic rdiogrphs. Similrly, Vllo et l highlighted sttisticlly significnt difference in the identifiction of picl periodontitis in the posterior mxill etween pnormic rdiogrphy nd CBCT, with the ltter eing more fvourle. 7 Novemer 2018 DentlUpdte 979
Figure 4. (, ) A 32-yer-old femle presented with recurrent intr-orl nd nsl pus dringe. The upper left third molr ws extrcted three yers erlier nd the pnormic rdiogrph highlights the loss of the hrd tissue shdow of the left pterygomxillry fissure. The xil section of the CT scn shows well-defined corticted ovoid lesion contining irregulr soft tissue. She ws dignosed with 4 cm thick-wlled, odontogenic kertocyst occupying the left mxillry sinus. c Figure 5. ( c) A 28-yer-old mle presented with n symptomtic, slow-growing, left-sided, extrorl swelling of the mxill. The CT scn indicted tht there is lrge nd expnsive presumed cystic ony mss in the nterolterl spect of the mxill. The cystic mss encroches the nterior hlf of the left mxillry ntrum nd mesures 5.5 x 3.9 x 4 cm. The shdow of the left nteromedil wll on the pnormic rdiogrph is completely lost. The 3-D reconstruction illustrted the extent of the lesion perforting through the nterolterl wll of the mxill, hence the ility to plpte the lesion on presenttion. Histopthologicl findings indicted tht this ws likely to e lrge residul cyst. A recent study y Du et l exmined the dignostic ccurcy of pnormic rdiogrphy versus CBCT in symptomtic mxillry sinus pthologies. 8 It ws concluded tht pnormic rdiogrphy lone ws insufficient in evluting sinus disese, however, it still remins useful dignostic tool, depending on the clinicin s trining nd expertise. Similr findings were reported y Mlin-Altzinger et l, with dvnced imging providing more consistent nd precise evlution of specific mxillry sinus conditions. 9 980 DentlUpdte Novemer 2018
Figure 6. (, ) A 49-yer-old mle presented with left-sided nsl ostruction nd foul tste in his mouth. The left nteromedil wll ppered prtilly sent on the pnormic rdiogrph. A CT scn showed expnsion of the nterior nd lterl wll of the left mxill. The upper left third molr is emedded in the posterior wll of the mxillry sinus. A dentigerous cyst ssocited with the unerupted upper left third molr completely occupies the left mxillry sinus. Figure 7. (, ) A 68-yer-old femle directly referred from GDP for left-sided, slow-growing swelling of the fce. On exmintion, there ws n ovious swelling on the left mxillry prominence nd zygomtic re. The pnormic rdiogrph confirms its cystic nture with the loss of the left zygomtic uttress nd periodontl ligment spce of the upper left second nd third molrs. The CT scn illustrted homogeneous cystic lesion tht expnds superiorly in the left mxillry ntrum nd protrudes medilly into the middle nd inferior turintes, cusing prtil lockge of the nsl ir spces. Enucletion of the entire cyst nd histopthologicl findings confirmed the lesion s n odontogenic kertocyst. Figure 8. (, ) A 26-yer-old mle presented to our er, nose nd throt (ENT) collegues complining of left-sided nsl ostruction nd epiphor. He hd 4-month history of n incresing, non-pinful ony swelling in the left mxill, specificlly in the region of the upper left first premolr, second premolr nd first molr. The left nteromedil wll of the mxillry ntrum is sent on the pnormic rdiogrph. One should note the lrge peripicl rdiolucent lesions ssocited with the roots of the upper right nd left first molrs. The CT scn identified lrge expnsile 3 x 4.4 x 4 cm ony cystic lesion occupying the entire left mxillry sinus nd completely locking its dringe. The size of this lesion hs cused olitertion of the left nsl cvity nd devition of the nsl septum. There is smller ony cystic lesion in the right mxillry ntrum. Enucletion of the ilterl cysts ws performed nd confirmed s rdiculr cysts ssocited with the upper right nd left first molrs. Novemer 2018 DentlUpdte 983
Dryz cretes dry working environment every time. Conclusion Whilst cution is dvised for the use of pnormic rdiogrphy in eliminting the presence of disese, it cn e relile indictor of extension of the disese process through the wlls of the mxillry sinus. It should e pprecited tht the floor nd medil nd posterior wlls of the ntrum re well shown on pnormic rdiogrphs. Consequently, it is useful djunct for indicting lrge disese processes tht hve perforted the sinus wlls. This is criticl s lesions will often fill the sinus spce efore ptient symptoms re displyed. The use of such 2-D rdiogrphic imging should not e underestimted, ut it is cler tht it should e supplemented with fr superior imging techniques prior to ny intervention to id in dignosis nd surgicl plnning. This cse series hs outlined the vlue in detecting distortion or sence of three ntomicl lndmrks on pnormic rdiogrphs. This initil incidentl finding hs led to chnge of pproch t consultnt nd junior level. Clinicins would enefit y hving n incresed wreness of certin rdiogrphic fetures, which indicte the need for further imging, nd the im is for this level of understnding to e trnslted to the primry cre setting. It is the uthors recommendtion tht clinicins should identify such chnges in pnormic rdiogrphs nd correlte this informtion with the clinicl findings to mke n pproprite referrl to specilist in secondry or tertiry cre setting. At this stge, sed on the history nd clinicl exmintion, the need for more relile nd dvnced imging, such s CT or CBCT, should e considered. Conflicts of interest: None. References Dryz Gingivl Hemosttic Retrction Pste stops gingivl leeding nd seepge tht my interfere with impression tking. 1. Whites E, Drge N. Essentils of Dentl Rdiogrphy nd Rdiology 5th edn. Edinurgh: Churchill Livingstone/Elsevier, 2013. 2. Bell GW, Joshi BB, Mcleod RI. Mxillry sinus disese: dignosis nd tretment. Br Dent J 2011; 210: 113 118. 3. Frmn AG, Nortjé CJ. Pthologic conditions of the mxillry sinus. Pnormic Imging News 2002; 2: 1 6. 4. Shhzin M, Vndewoude C, Wytt J, Jcos R. Comprtive ssessment of pnormic rdiogrphy nd CBCT imging for rdiodignostics in the posterior mxill. Clin Orl Invest 2014; 18: 293 300. 5. British Institute of Rdiology, Society nd College of Rdiogrphers. A Guide to Understnding the Implictions of the Ionising Rdition (Medicl Exposure) Regultions in Dignostic nd Interventionl Rdiology. London: The Royl College of Rdiologists, 2015. 6. Tdind A, Fung K, Thcker S, Mhdin M, Jdhv A, Schincgli GP. Rdiogrphic evlution of the mxillry sinus prior to dentl implnt therpy: comprison etween two-dimensionl nd three-dimensionl rdiogrphic imging. Imging Sci Dent 2015; 54: 169 174. 7. Vllo J, Suominen-Tiple L, Huumonen S, Soikkonen K, Norld A. Prevlence of mucosl normlities of the mxillry sinus nd their reltionship to dentl disese in pnormic rdiogrphy: results from the Helth 2000 Helth Exmintion Survey. Orl Surg Orl Med Orl Pthol Orl Rdiol Endod 2010; 109: 80 87. 8. Du M, Mrcik P, Al-Nws B et l. Evlution of symptomtic mxillry sinus pthologies using pnormic rdiogrphy nd cone em computed tomogrphy influence of professionl trining. Int J Implnt Dent 2017; 3: 13. 9. Mlin-Altzinger J, Dmeru G, Grätz KW, Bernd Stdlinger PD. Evlution of the mxillry sinus in pnormic rdiogrphy comprtive study. Int J Implnt Dent 2015; 1: 17. 984 DentlUpdte Novemer 2018