1http://dx.doi.org/10.20396/bjos.v20i00.8661223 Volume 20 2021 e211223 Original Article 1 Academic of the Speech Therapy Course – Federal University of Health Sciences of Porto Alegre - UFCSPA, Porto Alegre, Brazil 2 Department of Public Health, Federal University of Health Sciences of Porto Alegre – UFCSPA, Porto Alegre, Brazil 3 Department of Speech-language pathology, Federal University of Health Sciences of Porto Alegre – UFCSPA, Porto Alegre, Brazil 4 Cristo Redentor Hospital – Conceição Hospital Group, Porto Alegre, Brazil Corresponding author: Esther da Cunha Rodrigues. 245, Sarmento Leite. Porto Alegre, Rio Grande do Sul. Brasil. Zip Code: 90050-170 E-mail: esthercunha.rs@gmail.com Editor: Dr Altair A. Del Bel Cury Received: September 15, 2020 Accepted: February 10, 2021 Diagnostic properties of sensitivity changes in patients with maxillofacial fractures: a systematic review Esther Cunha Rodrigues1,* , Eliana Márcia Da Ros Wendland2 , Deisi Cristina Gollo Marques Vidor3 , Karoline Weber dos Santos4 Aim: Verify the accuracy of objective assessments compared to subjective tests in detecting changes in somatosensory perception in individuals affected by maxillofacial trauma. Methods: The review (PROSPERO n ° CRD42019125546) used the databases: MEDLINE, Cochrane, EMBASE, LILACS and other bibliographic resources. Prospective and retrospective studies that used objective and subjective methods of assessing facial sensitivity in maxillofacial fractures were included. There was no restriction on language or publication date. Risk of bias was assessed using the QUADAS-2. Data extraction and analysis were performed using a form developed for the study. Results: 21 studies were included. The clinical objective examination mainly includes assessments of: tactile sensitivity (95.24%) and nociceptive sensitivity (57.14%).The subjective assessment was based on the patient’s report, spontaneously (61.90%), guided by structured questionnaires (33.33%) and/or using scales (9.52%) to measure the degree of impairment. In risk of bias assessment, ZHUH�REVHUYHG�QR�DGHTXDWH�LQWHUSUHWDWLRQ�DQG�FODVVLͤFDWLRQ�RI� changes in subjective sensitivity, subject to inappropriate analysis of the data. In addition, the studies bring several instruments without standardization for assessing sensory modalities. Conclusion: The objective assessment is a complement to the subjective assessment, using the touch assessment as the main SDUDPHWHU�LQ�WKH�SURͤOH�RI�WKH�IDFLDO�SHULSKHUDO�LQWHJULW\��DVVRFLDWHG� or not with nociceptive assessment. Lack of consensus on the LQGLFDWLRQ�RI�VSHFLͤF�LQVWUXPHQWV�IRU�WHVWLQJ�LV�D�OLPLWLQJ�IDFWRU�� Thus, based on the studies, is proposed a minimum battery of sensitivity assessment to obtain an overview of the patient’s peripheral nervous situation. KEYWORDS: Facial injuries. Zygomatic fractures. Jaw fracture. Somatosensory disorders. Sensation disorders. Systematic reviews as topic. https://orcid.org/0000-0001-5745-0094 https://orcid.org/0000-0001-6356-6413 https://orcid.org/0000-0003-4805-6145 https://orcid.org/0000-0003-0524-5878 2 Rodrigues et al. Introduction Trauma involving the skull and face are among the leading causes of morbidity and mortality, especially in the young population1. It is estimated that, globally, there are 7.5 million new cases of facial fractures with 1.8 million people living with their comorbidities2��:LWK�RFFXUUHQFH�LQ�PRUH�VLJQLͤFDQW�QXPEHUV�LQ�PDOH�LQGLYLGXDOV�� LQMXULHV�DUH�WKH�UHVXOW�RI�WUDIͤF�DFFLGHQWV��IDOOV��SK\VLFDO�YLROHQFH��DVVDXOWV��RFFXSD- tional, and sports accidents1,3. In general, besides bone fractures, individuals have other injuries that can limit their functional capacity3. Among these traumas, maxillofacial traumas, as well as their repair procedures, cause bone dislocations that can result in lesions in the peripheral nerve, which are responsible for facial sensation and perception. Thus, compression, section- ing, or stretching of the branches of the trigeminal nerve (V1, V2, and V3) and the nerves of the cervical plexus (C1 and C2)4 may result in somatosensory changes that impact functionality, quality of life, and well-being of individuals. It may impair the functions of chewing, breathing, swallowing, sucking, and speaking5. The diag- nosis of these changes is based on clinical and instrumental assessment, which considers the patient’s report, the use of subjective questionnaires and quantitative neurosensory tests5,6. 6XEMHFWLYH�YHULͤFDWLRQ�EDVHG�RQ�WKH�V\PSWRP�UHIHUUHG�E\�WKH�SDWLHQW�LV�WKH�JROG� standard to determine the diagnosis, as it considers aspects of somatosen- sory perception more comprehensively. In it, individuals are submitted to a qual- itative assessment of changes in sensory perception5,6. It considers param- eters such as the presence or absence of change and the description of the change sensation5. The objective assessment of sensory changes, represented by quantitative tests, is based into parameters that assess the patient’s perception according to the different somatosensory modalities explored. It determines the profile of the detection of thermal, painful, touch, and proprioceptive stimuli, using instru- ments to identify perception and quantitative measurement of perceptual thresh- olds6. The objective assessment of facial sensitivity uses different techniques. They can be classified according to the type of fiber being stimulated. It may be DVVRFLDWHG�ZLWK�$ƌ�ILEHUV��P\HOLQDWHG��WKURXJK�WHVWV�LQYROYLQJ�WRXFK�VHQVDWLRQ�� RU�P\HOLQDWHG�$�Ǝ�ILEHUV�DQG�&�ILEHUV��QRW�P\HOLQDWHG��E\�YHULI\LQJ�WKHUPDO�DQG� nociceptive sensation)6. Thus, the present study aims to conduct a systematic review of the literature to verify the accuracy of objective tests compared to subjective tests of facial sensi- tivity in detecting changes in somatosensory perception in individuals affected by maxillofacial trauma. Materials and methods This review was conducted based on the guidelines proposed by the Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy reported follow- 3 Rodrigues et al. ing the PRISMA7 recommendations and registered in PROSPERO under number CRD42019125546. Studies that used objective and subjective methods of assess- ing facial sensitivity in patients with maxillofacial trauma were included. Criteria for including studies in this review Types of studies Studies that used objective and subjective methods to assess facial sensitivity to detect peripheral somatosensory changes resulting from maxillofacial trauma were included. Prospective and retrospective studies were considered, provided they had both exams. Participants Studies with an assessment of patients with sensory changes in the peripheral ner- vous system originating from trauma or postoperative traumatic maxillofacial inju- ries. Participants underwent at least one of the modalities of objective assessment and at least one modality of subjective sensitivity assessment. Index test Changes in facial sensitivity must have been assessed objectively using quantitative tests or scales. Reference standard All patients must have been subjected to a subjective assessment of changes in sensory perception considering the following parameters: presence or absence of change or description of the sensation. Target conditions Changes in the peripheral sensory perception of the face. 6HDUFK�PHWKRGV�IRU�VWXG\�LGHQWLͤFDWLRQ� The search was carried out in the MEDLINE, Cochrane, EMBASE, Scopus, and LILACS databases of articles published until March 2019, using the following terms and their correlates: “facial fractures,” “zygomatic-orbital fracture,” “mandibular fractures,” and “somatosensory disorders.” The search strategy for each database is available in Appendix 1. The search was complemented by the manual review of RWKHU�ELEOLRJUDSKLF�UHVRXUFHV�LQ�WKH�KHDOWK�ͤHOG��VXFK�DV�*RRJOH�6FKRODU��2SHQ*UH\�� ProQuest, dissertations, theses, and reference lists. There was no restriction on lan- guage or publication date. The authors of the selected studies were contacted to UHTXHVW�PLVVLQJ�RU�LQVXIͤFLHQW�GDWD� 4 Rodrigues et al. Data collection and analysis Selection of studies The studies were initially analyzed by title and abstracts by two indepen- dent evaluators (KWS and ECR), including studies that met the eligibility crite- ria. A third evaluator (DCGMV) judged doubts regarding the inclusion to obtain consensus. Those eligible in this stage were read in full for a final decision on their inclusion. Those selected were registered on a form regarding inclusion or exclusion in the study at each step of the selection process, as well as the respective reasons. Data extraction and management 7KH�GDWD�IURP�WKH�LQFOXGHG�VWXGLHV�ZHUH�H[WUDFWHG�LQWR�D�IRUP�GHYHORSHG�VSHFLͤFDOO\� for this analysis. First, data on the characteristics of the studies and their popula- tion were tabulated. Data were also extracted regarding the objective and subjective assessment methods used, as well as a description of the facial sensitivity assess- ment techniques performed. Assessment of methodological quality The studies were assessed regarding quality using the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2)8 by two independent evaluators (KWS and ECR) and, in case of disagreement, a third evaluator (DCGMV) was consulted. Divided into four domains (patient selection, index test, reference standard, and flow and timing) the QUADAS-2 tool analyzes the methodological quality of the included studies, judging the risk of bias and applicability8. RESULTS Study selection Out of the 7782 titles and abstracts analyzed from the search strategies, 135 met the eligibility criteria for reading the full manuscript. The authors of four arti- cles9-12 were contacted for more information on the methodology used in their studies, but they were excluded due to a lack of responses. Thus, for quality anal- ysis, 21 studies13-33 were included. The PRISMA flow diagram (Figure 1) provides, according to the different phases of the systematic review, the registration of the identified, included and excluded studies, and the reasons for the exclusions. 5 Rodrigues et al. Study characteristics The characteristics of the studies included are described in Table 1. The studies were predominantly observational (85.71%), with a sample composed of individuals aged between 11 and 83 years, mostly males. Individuals from 11 years old were included when they presented the same type of intervention used in adults34. Despite the liter- DWXUH�FLWLQJ�VSHFLͤF�IDFLDO�VHQVLWLYLW\�WHVWV�WKDW�VKRZ�GLIIHUHQW�DFFRUGLQJ�WR�WKH�LQGL- vidual’s age and sex4, the studies included in this review do not show differences in results in the assessments regarding the age and sex variables. Among the causes of trauma, from the most recurring to the least common are: WUDIͤF�DFFLGHQWV��SK\VLFDO�YLROHQFH��DVVDXOWV��IDOOV��VSRUWV�DFFLGHQWV��ͤUHDUP�LQMXULHV�� work accidents, and domestic accidents. The most frequent type of fracture was the middle third of the face (52.38%), involving the regions of the zygoma, maxilla, and orbit; mandibular fractures (38.10%), including the regions of the body, angle, branch, V\PSK\VLV�� SDUDV\PSK\VLV�� KHDG�� DQG� FRQG\ODU� SURFHVV�� DQG� ͤQDOO\�� ELPD[LOODU\� ���������&RQFHUQLQJ�VXUJLFDO�LQWHUYHQWLRQV��PRVW�RI�WKHP�KDG�D�ULJLG�LQWHUQDO�ͤ[DWLRQ� with open reduction (76.19%), with intra-oral (37.5%), extra-oral (37.5%), or combined ������LQFLVLRQV��6RPH�VWXGLHV���������PHQWLRQ�WKH�XVH�RI�PD[LOORPDQGLEXODU�ͤ[DWLRQ� to stabilize the fracture, and others also bring conservative treatment (14.28%) as an option for trauma management. Records identified through database search (n = 5733) Additional records identified through other sources (n = 2111) Id en tifi ca tio n Sc re en in g El ig ib ili ty In cl ud ed Records after duplicates removed (n = 7782) Records screened based on title and abstract (n = 7782) Records excluded (n = 7647) Did not fulfill screening/ inclusion criteria Full-text articles assessed for eligibility (n = 135) Studies included in qualitative synthesis (n = 21) Full-text articles excluded, with reasons (n = 114) 91 studies without index test, reference test or both; 4 studies not fulfill methodology set out in inclusion criteria; 15 studies the population is not adequate to the elegibility criteria; 4 unavailable studies. Figure 1.�46-71%�ƽS[�HMEKVEQ� 6 Rodrigues et al. Ta bl e 1. C ha ra ct er is tic s of th e st ud ie s in cl ud ed A ut ho r, Y ea r C ou nt ry S tu dy D es ig n A ge n (F /M ) C au se o f T ra um a Lo ca ti on o f f ra ct ur e M ax ilo fa ci al S ur ge ry S ur gi ca l i nc is io n A nc hl ia , 20 18 13 In di a 3 RI �E VQ �G PMR MG EP � tr ia l A ve ra ge 3 0 ye ar s 20 (6 /1 4) 8V Eƾ G� EG GM HI RX W� �� �� � �� -R XI VT IV WS RE P�Z MS PI RG I� �� �� � M an di bl e fr ac tu re s: - B od y fr ac tu re s (p as si ng XL VS YK L� XL I� Q IR XE P�J SV EQ MR E O R IF In tr ao ra l v es tib ul ar in ci si on N eo vi us , 20 17 14 7[ IH IR R et ro sp ec tiv e C oh or t N D 81 (1 6/ 65 ) 8V Eƾ G� EG GM HI RX W� �� � % WW EY PXW ��� � *E PP� MR ��� � 3 XL IV W� �� � -W SP EX IH �^ ]K SQ EX MG �JV EG XY VI � �� � -W SP EX IH �F PS [ �S YX �JV EG XY VI ��� � >] KS Q EX MG �JV EG XY VI �G SQ FM RI H� [ MXL �E �F PS [ �S YX �JV EG XY VI �E RH � �� & MPE XI VE P�S V�Q YP XMT PI �JV EG XY VI � �� �� O R a nd / or O R IF 0S [ IV �I ]I PMH �MR GM WM SR O ko ch i, 20 15 15 Ja pa n R et ro sp ec tiv e C oh or t �� �� �r �� �� � 10 (4 /6 ) *E PP� MR ��� � 7T SV XW �E GG MH IR XW ��� � � 8V Eƾ G� EG GM HI RX W� �� � 9 RM PE XI VE P�^ ]K SQ EX MG SQ E\ MPP EV ]� GS Q TP I\ �JV EG XY VI O R IF 0E XI VE P�I ]I FV S[ ��P S[ IV � ey el id s ub ci lia ry a nd in tr ao ra l a pp ro ac h Sc ot t, 20 14 16 U K R et ro sp ec tiv e C oh or t N D 15 0 N D & SH ]� �E RK PI �E RH �VE Q YW ��T EW WM RK � FI X[ II R� XL I� Q ER HM FY PE V�E RH � Q IR XE P�J SV EQ IR O R IF In tr ao ra l a pp ro ac h M ay rin k, 20 12 17 B ra zi l P ro sp ec tiv e C oh or t A ve ra ge �� �� �� (r an ge 1 5 to 6 8) 19 (4 /1 5) 8V Eƾ G� EG GM HI RX W� �� �� �� *E PP� �� �� � -R XI VT IV WS RE P�Z MS PI RG I� �� �� �� 7] Q TL ]W MW ��F SH ]� �E RK PI ��V EQ YW � an d co nd yl ar p ro ce ss , i so la te d SV �G SQ FM RI H O R IF )\ XV E� FY GG EP ��X VE RW ��E RH � in tr ab uc ca l ( in b od y an d co nd yl e fr ac tu re s MR �XL I� WE Q I� TE XMI RX B ag he ri, 20 09 18 U SA R et ro sp ec tiv e C oh or t A ve ra ge �� �� ��V ER KI � 11 to 6 1) 42 (1 7/ 2 5) N D >] KS Q EX MG SQ E\ MPP EV ]� GS Q TP I\ JV EG XY VI ��T EV EW ]Q TL ]W MW ��E RK PI �� VE Q YW �E RH �Q ER HM FP I� FS H] N D N D Sa ka vi ci us , 20 08 19 Li th ua ni a R et ro sp ec tiv e C oh or t M ea n 32 ,1 7 (r an ge 1 5 to 7 8) 47 8 (8 6/ 39 2) % WW EY PXW ��� �� �� � 6 SE H� XV Eƾ G� EG GM HI RX W� �� �� �� � 7T SV XW �E GG MH IR XW ��� �� �� � 3 XL IV W� �� �� �� 9 RM PE XI VE P�^ ]K SQ EX MG SQ E\ MPP EV ]� GS Q TP I\ �JV EG XY VI W C lo se d re du ct io n or O R IF if HM WT PE GI Q IR X C lo se d re du ct io n or PS [ IV �I ]I PMH �W YF GM PME V] � ap pr oa ch B ar ry , 20 07 20 Ir el an d R et ro sp ec tiv e C oh or t 1 IE R� �� �� � (r an ge 1 6 to 4 2) 50 (2 /4 8) In te rp er so na l v io - PI RG I� �� � 7T SV XMR K� MR NY V] ��� � *E PPW ��� � 1 SX SV �Z IL MG PI �E GG MH IR XW ��� % RK PI �E RH �VE Q YW ��� �� [ IV I� EW WS GM EX IH �[ MXL �E R� MQ TE GX IH �S V� IV YT XI H� XL MVH �Q SP EV ��� XI IX L� MR �XL I� lin e of fr ac tu re ) 3 6 -* �[ MXL �1 1 *� if oc cl us al HM WT PE GI Q IR X )\ XI RH IH �XL MVH �Q SP EV � in ci si on C on tin ue 7 Rodrigues et al. C on tin ua tio n Iiz uk a, 19 91 21 Fi nl an d P ro sp ec tiv e C oh or t 1 IE R� �� �� � (r an ge 1 6 to 8 3) 13 3 (2 5/ 10 8) N D & SH ]� �E RK PI �E RH �VE Q YW ��T EW WM RK � FI X[ II R� XL I� Q ER HM FY PE V�G ER EP O R IF )\ XV ES VE P� �W YF Q ER HM FY PE V�S V� VI XV SQ ER HM FY PE V �E RH � in tr ao ra l a pp ro ac h Fo ga ça , 20 04 22 B ra zi l R et ro sp ec tiv e C ro ss -s ec tio na l N D 25 N D 9 RM PE XI VE P�^ ]K SQ E� JV EG XY VI W O R IF N D Fa ya zi , 20 13 23 + IV Q ER ] P ro sp ec tiv e ' SL SV Xɸ �� r� �� � (r an ge 10 to 6 5 ye ar s) 49 (5 /4 4) 1 SX SV �Z IL MG PI �E GG MH IR X�� �� �� � 7T SV X�I ZI RX W� �� �� � -R XI VT IV WS RE P�Z MS PI RG I� �� �� � � *E PPM RK ��� �� 4 EV EW ]Q TL ]W MW ��W ]Q TL ]W MW �� co nd yl ar p ro ce ss a nd h ea d, FS H] ��E RK PI ��V EQ YW ��G SV SR SM H� TV SG IW W� JV EG XY VI Wɸ M M F Er ic h ar ch b ar s Si dd iq ui , 20 07 24 U K 6 ER HS Q M^ IH � GS RX VS PPI H� XV ME Pɸ R an ge 1 7 to 5 7 85 (1 0/ 75 ) N D % RK PI �E RH �VE Q YW ��G SQ Q MR YX IH � JV EG XY VI W� [ IV I� I\ GP YH IH O R IF % X�X LI �I \X IV RE P�S FP MU YI � rid ge o r t ra ns bu cc al 1 G+ MQ TW I] �� 20 00 25 U K C ro ss -s ec tio na l R an ge 1 1 to 8 0 45 (4 5M ) % WW EY PX� �� �� �� �* EP PW ��� �� �� � 8V Eƾ G� EG GM HI RX W� �� �� �� Sp or ts EG GM HI RX W� �� �� � >] KS Q EX MG �G SQ TP I\ G ill ie s el ev at io n, 4 SW [ MPP S� LS SO �� E� GS Q FM RE XMS R� of b ot h G ill ie s ER H� 4 SW [ MPP S� SV � co ns er va tiv e 8I Q TS VE P�� + MPP MI W � ap pr oa ch V rie ns , 19 98 26 N et he rla nd s P ro sp ec tiv e C oh or t �� �� r� �� �� � (r an ge 1 4 to 7 7) 65 N D >] KS Q EX MG SQ E\ MPP EV ]� GS Q TP I\ fr ac tu re a nd o rb it �J VS RX S^ ]K SQ EX MG �W YX YV I� SV � SV FM XE P�F PS [ �S YX � O R IF 8I Q TS VE P�� + MPP MI W � ap pr oa ch K ip pe r, 20 16 27 B ra zi l C ro ss -s ec tio na l st ud y A bo ve 1 8 ye ar s 14 N D >] KS Q E� ER H� SX LI V�J VE GX YV IW N D N D Fo ga ça , 20 08 28 B ra zi l C ro ss -s ec tio na l st ud y N D 25 (9 /1 6) N D >] KS Q E� ER H� SV FM X O R IF N D / IW EV [ ER M�� 19 89 29 C an ad a R et ro sp ec tiv e C oh or t M ea n 37 (r an ge 1 8 to 5 7) 20 (4 /1 6) N D 4 ER JE GM EP �JV EG XY VI W� �Q E\ MPP E� � SV FM X�� RE WS IX LQ SM H� �^ ]K SQ E� ER H� Q ER HM FP I O R IF ' SV SR EP �ƽ ET W� � su bc ili ar y, u pp er a nd PS [ IV �F YG GE P�W YP GY Wɸ A bd El -K ad er , 20 11 30 Eg yp t 3 RI �E VQ �G PMR MG EP � XV ME Pɸ M ea n 31 (r an ge 2 0 to 4 2) 12 (2 /1 0) 8V Eƾ G� EG GM HI RX W� �� �� �� -R XI VT IV WS RE P�Z MS PI RG I� �� �� �� >] KS Q EX MG SQ E\ MPP EV ]� GS Q TP I\ � fr ac tu re O R IF Su bc ili ar y, bu cc og in gi va l a nd PE XI VE P�I ]I FV S[ � ap pr oa ch es C on tin ue 8 Rodrigues et al. C on tin ua tio n Le on ha rd t, 20 05 31 + IV Q ER ] P ro sp ec tiv e C oh or t M ea n 31 (r an ge d 15 to 7 0) 30 N D % RK PI �E RH �VE Q YW O R IF In tr ao ra l M ar zo la , 20 06 32 B ra zi l P ro sp ec tiv e C oh or t R an ge 1 1 to 5 1 10 0 (1 9/ 81 ) -R XI VT IV WS RE P�Z MS PI RG I� �� � � 8V Eƾ G� EG GM HI RX W� �� � ( SQ IW XMG �E GG MH IR XW ��� � 7T SV XW �E GG MH IR XW ��� ; SV OM RK �E GG MH IR XW ��� 3 XL IV W� �� � � >] KS Q EX MG SQ E\ MPP EV ]� GS Q TP I\ � fr ac tu re O R IF o r co ns er va tiv e N D % LQ IH �� 20 10 33 In di a P ro sp ec tiv e C oh or t *V SQ �� �� ye ar s 13 3 (3 /1 30 ) N D >] KS Q E N D N D 0I KI RH ��2 ( ��R SX �H IW GV MF IH ��3 6 -* ��3 TI R� 6 IH YG XMS R� -R XI VR EP �* M\ EX MS R� �1 1 *� �1 E\ MPP SQ ER HM FY PE V�* M\ EX MS R 9 Rodrigues et al. Risk of bias Figure 2 gathers the results of the quality analysis, which is described below. Patient Selection Thirteen (61.90%) studies13-17,19,21,25-31 had a high risk of bias and 8 (38,10%) studies17,18,20,22-24,32,33 had a low risk due to comparing individuals with changes to healthy individuals in case-control designs. As for applicability, all studies were con- VLGHUHG�DGHTXDWH��VLQFH�WKH�SDWLHQW�SURͤOH�ZHUH�LQ�DFFRUGDQFH�ZLWK�WKH�HOLJLELOLW\�FUL- teria listed for this review. Index Test As for the risk of bias concerning the objective sensitivity test, 20 (95.24%) studies13-21,23-33 had high risk, and 1 (4.76%) study22 had low risk. The high rate of bias was due to the lack of blinding to subjective assessment by the examiner to perform the objective tests. The non-independent assessment may have distorted the execution or interpretation of the objective test. Also, there was no adequate description of the interpretation of the tests, without description of diagnostic thresholds. As for applicability, all studies were considered adequate, as they con- template the review proposal. Reference Standard 3 (14.29%) studies22,29,33 had high risk and 18 (85.71%) studies13-21,23-27,29-32 low risk. It was considered a low-risk criterion when the reference test was conducted accord- ing to the patient’s report, without adaptation of the terms by the researchers. As for applicability, 19 (90.48%) studies13-21,23-32 showed good applicability, and 2 (9.52%) studies22,33 showed flaws in their applicability. In one of the studies, there was an interpretation of the perceptual responses by the authors33, which may distort the data obtained. In another, the assessment procedures were not adequately described IRU�DFFXUDWH�FODVVLͤFDWLRQ22. Figure 2.�1IXLSHSPSKMGEP�IZEPYEXMSR�EGGSVHMRK�XS�59%(%7���SJ�XLI�MRGPYHIH�WXYHMIW� Patient Selection Index Test Reference Standard Flow and Timing 0% 25% 50% 75% 100% Risk of Bias Applicability Concerns High Unclear Low 0% 25% 50% 75% 100% 10 Rodrigues et al. Flow and timing $OO�VWXGLHV�ZHUH�FODVVLͤHG�DV�KDYLQJ�D�ORZ�ULVN�RI�ELDV��DV�LW�ZDV�FRQVLGHUHG�WKDW�WKH� application interval between the reference test and the index test is not a variable that can interfere with the test results. All patients in the studies were submitted to the index and reference tests and included in the data analysis. Assessments The characteristics of the facial sensitivity assessment are described in Table 2. The assessment moments involved periods of the preoperative period (4.76%), postoperative period (47.62%), and both (42.86%), and some had followed up to complete nervous recovery (4.76 %). The postoperative follow-up time varied, being SHUIRUPHG�LQ�WKH�SHULRG�EHWZHHQ�WKH�ͤUVW�ZHHN�����������WKH�ͤUVW�PRQWK����������� the second month (14.28%), the third month (42.86%), the sixth month (42.86%), DQG�WKH�ͤUVW�\HDU�����������6RPH�VWXGLHV14-16,29 extend the follow-up to more than one year (19.05%) after surgery. Facial sensitivity assessments were performed to check the activity of the following nerve portions: infraorbital (61.90%), lower alveolar (38.10%), supraorbital (4.76%), lin- gual (4.76%), and buccal (4.76%). Thus, classifying the assessments from the main branch of the trigeminal nerve, it is observed: 61.90% ophthalmic branch, 42.86% mandibular branch, and 4.76% maxillary branch. As for the assessed facial region, the assessment of the ophthalmic branch was performed on the upper lip (53.85%), cheeks (38.46%), nasal and paranasal region (46.15%), eyelids (23.08%), gingiva (7.69%), and forehead (7.69%). The activity of the maxillary branch was observed in the region of the cheeks (100%) and the assess- ments of the mandibular branch in the lower lip (80%), chin (40%), labial commissures (10%), and lower border of the mandible (10%). :KHQ� DVVHVVLQJ� $ƌ� W\SH� ͤEHUV�� WRXFK� VHQVDWLRQ� ���������� WKH� IROORZLQJ� PHWK- ods were used: light touch/static light touch (59.09%), two-point discrimination (45.45%) - moving (20%) or static (60%), mechanical detection threshold (18.18%), direction sensation (13.63%), moving-touch discrimination (9.09%), stimulus local- ization (4.54%), vibratory sensation (4.54%), and trigeminal somatosensory evoked potential (4.54%). $V�IRU�$Ǝ�DQG�&�ͤEHUV��WKHUPDO�VHQVDWLRQ����������SDLQIXO���������RU�ERWK����������� the following measurements were used: painful stimuli/pinprick (75%), pain detection threshold (25%), thermal sensation (25%), and thermal discrimination (8.33%). 11 Rodrigues et al. Ta bl e 2. �* EG ME P�W IR WM FM PMX ]� EW WI WW Q IR X A ut ho r an d ye ar pu bl is he d M om en ts o f ev al ua ti on M om en ts o f ev al ua ti on – Fo llo w u p N er ve as se ss ed Ev al ua ti on R eg io n $ ƌ� ͤE HU V� �W RX FK � $ Ǝ� ͤE HU V� DQ G� & � ͤE HU V� �W HP SH UD WX UH � an d pa in ) S ub je ct iv e ev al ua ti on P re op . P os op . A nc hl ia , 20 18 13 N Y 1s t, 4t h an d 12 th [ II OW �E JX IV �W YV KI V] IA N ( V 3) 0S [ IV �PM T 0M KL X�X SY GL ��X [ S� TS MR X� HM WG VMQ MR EX MS R P in p ric k Q ue st io nn ai re N eo vi us , 20 17 14 N Y �� Ɓ �� �� �] IE VW IO N ( V 1) A la r b as e an d up pe r l ip 0M KL X�X SY GL ��Q IG LE RM GE P� de te ct io n th re sh ol d N E Sc al e (0 -1 00 ) O ko ch i, 20 15 15 Y Y -Q Q IH ME XI P] ��� �] IE V� an d 5 ye ar IO N ( V 1) Ey el id 0M KL X�X SY GL ��Q IG LE RM GE P� de te ct io n th re sh ol d C ur re nt p er ce pt io n th re sh ol d P at ie nt ’s re po rt Sc ot t, 20 14 16 N Y 1 MR MQ YQ �S J�� �� Q SR XL W� �Q E\ MQ YQ � RS X�W TI GM ƼI H IA N ( V 3) 0S [ IV �PM T Li gh t t ou ch N E Q ue st io nn ai re an d sc al e (0 -1 0) M ay rin k, 20 12 17 Y Y �� [ II O� �� �� ��� � Q SR XL W� ER H� �] IE V IA N ( V 3) 0E FM EP �G SQ Q MW WY VI ��G LM R� ER H� ho riz on ta lly b y la bi al in fe rio r FS VH IV ��Q IR XS PE FM EP �JS PH IV �E RH � PS [ IV �F SV HI V�S J�Q ER HM FP I St at ic li gh t t ou ch , b ru sh di re ct io na l s tr ok e 8L IV Q EP � HM WG VMQ MR EX MS R� ER H� pi n- p ric k Q ue st io nn ai re B ag he ri, 20 09 18 Y Y % JX IV �XV EY Q E� � TV I� ST ��� �[ II O� �� �� �� �� �Q SR XL W� ER H� 1 ye ar IA N ( V 3) , I O N (V 1) , L N ( V 3) an d B N ( V 3) N D 7X EX MG �PM KL X�X SY GL ��Q SZ MR K� FV YW L� WX VS OI W� �W XMQ YP YW �PS GE PM^ EX MS R� � WX EX MG �� �T SM RX �H MW GV MQ MR EX MS R 4 EM RJ YP �W XMQ YP M P at ie nt ’s re po rt Sa ka vi ci us , 20 08 19 Y Y �� [ II OW ��� ��� ��� �E RH � �� �Q SR XL W IO N ( V 1) RS WI ��G LI IO ��P S[ IV �I ]I PMH �� up pe r l ip , g in gi va l a nd te et h N E P ai n de te ct io n th re sh ol d P at ie nt ’s re po rt an d cl in ic al W] Q TX SQ W� B ar ry , 2 00 72 0 Y Y N D IA N ( V 3) N D �� TS MR X�H MW GV MQ MR EX MS R� �H MVI GX MS R� se ns at io n 8L IV Q EP �W IR WE XMS R Q ue st io nn ai re Iiz uk a, 19 91 21 Y Y �� �� [ II OW �E RH �� �� �� Q SR XL W� SR �E ZI VE KI IA N ( V 3) ' LM R� ER H� PS [ IV �PM T 0M KL X�X SY GL ��[ MXL �G SX XS R� [ SS P P in pr ic k (s ha rp /b lu nt HM JJ IV IR XME XMS R� [ MXL � a sh ar p de nt al p ro be ) P at ie nt ’s re po rt Fo ga ça , 20 04 22 N Y N E IO N ( V 1) >] KS Q EX MG SX IQ TS VE P�V IK MS R� � pa ra na sa l r eg io n, a nd u pp er lip 7X EX MG �E RH �Q SZ MR K� XS YG L� HM WG VMQ MR EX MS R� �W XE XMG �X[ S� TS MR X� HM WG VMQ MR EX MS R N E P at ie nt ’s re po rt C on tin ue 12 Rodrigues et al. C on tin ua tio n Le on ha rd t, 20 05 31 + IV Q ER ] P ro sp ec tiv e C oh or t M ea n 31 (r an ge d 15 to 7 0) 30 N D % RK PI �E RH �VE Q YW O R IF In tr ao ra l M ar zo la , 20 06 32 B ra zi l P ro sp ec tiv e C oh or t R an ge 1 1 to 5 1 10 0 (1 9/ 81 ) -R XI VT IV WS RE P�Z MS PI RG I� �� � � 8V Eƾ G� EG GM HI RX W� �� � ( SQ IW XMG �E GG MH IR XW ��� � 7T SV XW �E GG MH IR XW ��� ; SV OM RK �E GG MH IR XW ��� 3 XL IV W� �� � � >] KS Q EX MG SQ E\ MPP EV ]� GS Q TP I\ � fr ac tu re O R IF o r c on se rv at iv e N D % LQ IH �� 20 10 33 In di a P ro sp ec tiv e C oh or t *V SQ �� �� ]I EV W 13 3 (3 /1 30 ) N D >] KS Q E N D N D V rie ns , 19 98 26 N Y % ZI VE KI �� �� �Q ��7 ( � �� �� �VE RK I� �� �� � Q SR XL W IO N ( V 1) C he ek , o n ha ir- be ar in g sk in o f up pe r l ip 7X EX MG �XS YG L� �W XE XMG �X[ S� TS MR X� HM WG VMQ MR EX MS R C ol d se ns at io n an d pi np ric k P at ie nt ’s re po rt K ip pe r, 20 16 27 Y N N E IO N ( V 1) C he ek a nd u pp er li p St at ic to uc h N E qu es tio nn ai re Fo ga ça , 20 08 28 N Y N E IO N ( V 1) >] KS Q EX MG �VI KM SR ��T EV ER EW EP � re gi on , u pp er li p 7X EX MG �X[ S� TS MR X� HM WG VMQ MR EX MS R� GY XE RI SY W� pr es su re th re sh ol d (s ta tic p oi nt ), cu ta ne ou s pr es su re th re sh ol d �H ]R EQ MG �T SM RX �� GY XE RI SY W� pr es su re th re sh ol d (s ta tic X[ S� TS MR X ��G YX ER IS YW �T VI WW YV I� XL VI WL SP H� �H ]R EQ MG �X[ S� TS MR X N E P at ie nt ’s re po rt / IW EV [ ER M�� 19 89 29 N Y �] ��Q IE R� XI WX MR K� XMQ I� �� ] Su pr ao rb ita l ne rv e (V 1) , IO N ( V 1) , I A N (V 3) Fo re he ad , c he ek , c hi n an d th e ZI VQ MPM SR �S J�X LI �PS [ IV �PM T 1 SZ MR K� ER H� WX EX MG �X[ S� TS MR X� HM WG VMQ MR EX MS R� �Z MF VE XS V] �� cu ta ne ou s pr es su re th re sh ol ds N E P at ie nt ’s re po rt an d vi br at or y pe rc ep tio n A bd El -K ad er , 20 11 30 Y Y �� �E RH �� �� [ II OW IO N ( V 1) 0S [ IV �I ]I PMH ��P EX IV EP �W OM R� SJ � th e no se , u pp er li p 8V MK IQ MR EP �W SQ EX SW IR WS V] � ev ok ed p ot en tia l ( TS EP ) N E Q es tio nn ai re C on tin ue 13 Rodrigues et al. C on tin ua tio n Le on ha rd t, 20 05 31 + IV Q ER ] P ro sp ec tiv e C oh or t M ea n 31 (r an ge d 15 to 7 0) 30 N D % RK PI �E RH �VE Q YW O R IF In tr ao ra l M ar zo la , 20 06 32 B ra zi l P ro sp ec tiv e C oh or t R an ge 1 1 to 5 1 10 0 (1 9/ 81 ) -R XI VT IV WS RE P�Z MS PI RG I� �� � � 8V Eƾ G� EG GM HI RX W� �� � ( SQ IW XMG �E GG MH IR XW ��� � 7T SV XW �E GG MH IR XW ��� ; SV OM RK �E GG MH IR XW ��� 3 XL IV W� �� � � >] KS Q EX MG SQ E\ MPP EV ]� GS Q TP I\ � fr ac tu re O R IF o r c on se rv at iv e N D % LQ IH �� 20 10 33 In di a P ro sp ec tiv e C oh or t *V SQ �� �� ]I EV W 13 3 (3 /1 30 ) N D >] KS Q E N D N D Le ge nd : N E: N ot E va lu at ed ; N D : N ot D es cr ib ed ; I A N : I nf er io r A lv eo la r N er ve ; I O N : I nf ra or bi ta l N er ve ; L N : L in gu al N er ve ; B N : B uc ca l N er ve ; 14 Rodrigues et al. Procedures and measurements As for subjective assessment, it is always performed before the objective clini- cal examination, from touching the affected region, using materials, or the gloved hand. The subjective assessment was carried out based on the patient’s report, spontaneously (61.90%) or guided by structured questionnaires (33.33%), or using scales created for the respective studies (9.52%). When assessments based on the reports are used, they could take place from unstructured conversations between the researcher and the patient or contain questions with yes or no answers. The questions were related to changes in sensitivity, numbness, burning and tingling sensation, thermal sensitivity, pain, functional changes (mainly during feeding, such as bites on the lips and escape of food from the oral cavity) and interference in the individual’s daily life and quality of life. Some studies guide the comparison of sensory differences on the injured side with a region of the face with uninvolved innervation or a sensitive region of another part of the body. The use of scales sug- JHVWV�WKDW�WKH�SDWLHQW�FODVVLͤHV�WKH�FKDQJH�LQ�FDWHJRULHV��7KH�PRVW�FRPPRQ�DUH� represented visually by numbers, where zero corresponds to the absence of sen- sory complaints, and ten/hundred corresponds to severe sensory changes. For the subjective assessment to be reliable, the patient’s report must be considered. For this, the evaluator must investigate the sensory complaint, asking the patient to explain and describe the altered sensation. As for the objective assessment, studies advise that patients should be examined in a quiet room, with their eyes closed and in a comfortable position, preferably with a headrest. For each type of assessment, procedures are cited for carrying out the dif- ferent measurements proposed. The studies bring the following measurements and procedures/techniques for assessing touch and nociceptive sensation: • Light touch/static light touch (61.90%) - assessment of detection of light touch VWLPXOXV��VORZO\�DGDSWLQJ�QHUYH�ͤEHUV���2SWL+DLU�YRQ�)UH\�ͤODPHQWV�(MARSTOCK nerve test, Marburg, Germany)14, 6HPPHV�:HLQVWHLQ� PRQRͤODPHQW� (esthesio- meter)15,17,28,28, 0.7-mm-gauge needle (BD Precision GlideTM)17, Pressure-Speci- ͤHG�6HQVRU\�'HYLFH�(PSSD)22,28 and Cotton roll25; • Mechanical detection threshold (19.04%) - a gradual measurement of the detec- tion of light touch stimulus, of ascending and descending character to determine WKH�WKUHVKROG��VORZO\�DGDSWLQJ�QHUYH�ͤEHUV���2SWL+DLU�YRQ�)UH\�ͤODPHQWV (MARS- TOCK nerve test, Marburg, Germany)14 and 6HPPHV�:HLQVWHLQ� PRQRͤODPHQW (esthesiometer)15,28,29; • Direction sensation (14.28%) - assessment of the detection of the direction of movement, differentiation of movements up, down, right or left (rapidly-adapting QHUYH�ͤEHUV���0.7-mm-gauge needle (BD Precision GlideTM)17 and Dental cotton swab25; • Two-point discrimination - static or moving (47.62%) - assessment of the mi- QLPXP� GLVWDQFH� EHWZHHQ� WZR� VWDWLF� SRLQWV� �VORZO\�DGDSWLQJ� QHUYH� ͤEHUV�� RU� PRYLQJ��UDSLGO\�DGDSWLQJ�QHUYH�ͤEHUV��WKDW�WKH�SDWLHQW�FDQ�GLVFULPLQDWH�� Pres- VXUH�6SHFLͤHG�6HQVRU\�'HYLFH (PSSD)22,28, MacKinnon-Dellon Disk-Crimínator® (North Coast Medical, Inc.) or Aesthesiometer 2 point26,28,29; 15 Rodrigues et al. • Vibratory sensation (4.76%) - assessment of the detection of vibration and deter- mination of the threshold of the disappearance of the stimulus (rapidly-adapting QHUYH�ͤEHUV���Vibrometer and 256-cps tuning fork29; • Thermal discrimination (9.52%) - detection of temperature differences and deter- mination of cold or hot stimuli. Cotton-tipped applicator saturated with a spray freeze of -50°C temperature17, and Ethyl chloride vapor was sprayed onto a sphe- rical dental cotton bud (cold sensation) (diameter: 5 mm)26; • Painful stimuli/pinprick (33.33%) - assessment of painful stimulus detection: QHHGOH�KHOG�WKH�EHWZHHQ�WKXPE�DQG�LQGH[�ͤQJHU17 and 27-gauge needle25; • Pain detection threshold (14.29%) - a gradual measurement of the detection of painful stimuli, of an ascending and descending character to determine the threshold (aid in the determination of hypoalgesia): Neurometer CPT (Neurotron Inc)15and Non-invasive electrocutaneous stimulation19; • Sensory assessment/ sensory changes: • $VVHVVPHQW�RI�VHQVRULQHXUDO�GHͤFLWV�RI�WKH�LQIHULRU�DQG�PHQWDO�DOYHRODU�QHUYHV�� Thermography25 (4.76%); • Assessment of nerve function latency and amplitude: Trigeminal somatosen- sory evoked potential30 (4.76%). • Details on how to conduct facial sensitivity assessment procedures described in the articles are listed in Appendix 2. It was not possible to carry out a meta-analysis because the studies did not have VXIͤFLHQW�TXDQWLWDWLYH�GDWD�DQG�VKRZHG�KLJK�TXDOLWDWLYH�KHWHURJHQHLW\�LQ�WKH�DVSHFWV� of nomenclature, procedures, and equipment used in the sensitivity objective assess- ment procedures. DISCUSSION In this study, we found a varied number of procedures used to assess each sen- sory modality. Considering the high incidence of traumatic events that cover the facial region1-3,14,16,17,25 and the occurrence of sensitivity changes resulting from these episodes9,10,13-33, it is necessary to have tests that assess these changes accurately. Bearing in mind that the subjective procedures were considered as reference tests in WKLV�UHYLHZ��LW�ZDV�LGHQWLͤHG�WKDW�WKLV�DVVHVVPHQW�RFFXUV�LQ�D�YHU\�GLIIHUHQW�ZD\��XVLQJ� questionnaires with questions aimed at guiding the patient’s report and/or scales to PHDVXUH�WKH�GHJUHH�RI�UHSRUWHG�LPSDLUPHQW��,Q�ERWK�DVVHVVPHQW�PRGDOLWLHV��GLIͤFXO- WLHV�UHODWHG�WR�WKH�LQWHUSUHWDWLRQ�DQG�FODVVLͤFDWLRQ�RI�WKH�FKDQJHV�PHQWLRQHG�E\�WKH� patient are found, and the results are subject to inappropriate analyzes, distortion of the report, and inadequate diagnoses of the change. Also, there is qualitative hetero- geneity in the scales used by the authors, who create scales for the punctual assess- ment using variations of the visual analog scale14,16. Based on this, what is effective in most studies is the realization of a questionnaire with structured questions13,17,20,27,30,33 and the consideration of the patient’s report as a marker of change15,18,19,21-26,28,29,31,32 to guide the use of objective tests. 16 Rodrigues et al. The objective assessment of facial sensitivity must be seen as a complement to the subjective assessment, and it must involve a large number of procedures that FDQ�EH�OLVWHG�DFFRUGLQJ�WR�WKH�W\SH�RI�QHUYH�ͤEHU�WHVWHG��WRXFK��DQG�QRFLFHSWLYH�VHQ- sitivity (pain and temperature). Most of the articles used the touch assessment as WKH�PDLQ�SDUDPHWHU�LQ�WKH�SURͤOH�RI�WKH�SHULSKHUDO�LQQHUYDWLRQ�LQWHJULW\�RI�WKH�IDFH�� being13,15,16,20,21,25,26,30,32 or not14,17,18,22-24,27-30,33 associated with nociceptive assessment. About touch assessment, the method used in most studies is the detection of light touch stimulus, usually associated with the mechanical detection threshold, with WKH�XVH�RI�PRQRͤODPHQWV�ZLWK�IRUFH�YDOXHV�DOUHDG\�VWDQGDUGL]HG�IRU�PHDVXULQJ� cutaneous sensitivity thresholds. The method allows a gradual assessment of impairment and nervous recovery over time, in cases where there is a follow-up after the intervention14,15,17,27,28,30. The nociceptive assessment, on the other hand, YHULͤHV�WKH�QHUYH�ͤ EHUV�LQYROYHG�LQ�WKH�VHQVDWLRQ�RI�SDLQ�DQG�WHPSHUDWXUH��7KH�VWXG- LHV�SUHVHQW�JUHDWHU�YHULͤFDWLRQV�RI�WKH�SDLQIXO�VHQVDWLRQ13,15,17-19,21,25,26,31,32, eventually being accompanied by the sensation of temperature17,26,31. Regarding these modal- ities, when researching the sensation of pain, studies use the prick test13,17,18,21,25,26,32, and when researching the sensation of temperature, they determine if the patient differentiates cold and hot stimuli17,26. A limiting factor of these assessments refers WR�WKH�ODFN�RI�FRQVHQVXV�RQ�WKH�LQGLFDWLRQ�RI�VSHFLͤF�LQVWUXPHQWV�WR�FDUU\�RXW�WKH� tests, using heterogeneous equipment, which results in several protocols. Thus, based on the studies, a minimum battery of facial sensitivity assessment is proposed with the modalities and procedures that should be performed so that the applicator has a complete overview of the patient’s peripheral nervous situation and the regions affected. Assessments should be carried out, if possible, preoperatively and postoperatively (in cases of surgical intervention)15,17-21,25,30,31 because it is known that the changes may be the result of trauma or type of surgical treatment used21. In WKH�SRVWRSHUDWLYH�SHULRG��LW�LV�VXJJHVWHG�WKDW�UH�DVVHVVPHQWV�EH�PDGH�LQ�WKH�ͤUVW� week13,15-19,23,24,26,29-33��LQ�WKH�ͤUVW month13,17-19,23,31-33, in the third month13,17-19,23,24,30,31,33, in the sixth month17-19,23,26,31-33��DQG�LQ�WKH�ͤUVW�\HDU15-19,23,29,33 after surgery or trauma. It is recommended to start with the subjective assessment, which is important to identify the patient’s complaint and to delimit what results are expected from the objective tests later. At this stage, it is suggested questions to guide the patient’s report (Chart 1). Chart 1. Questions to guide the patient’s report Questions to guide the patient’s report: 1. Do you notice changes in the sensitivity of the face? 2. Do changes in sensitivity involve numbness, burning, tingling, pain or sensitivity to cold? Can you explain with your words how the sensation is? 3. Are your functionality and quality of life impaired? In what situations? (situations can be exemplified for the patient, such as: food runs through the mouth, drooling, biting of the lips.) 4. Comparing with the unaffected side (or with some other region of the face, in cases of bilateral fracture), do you feel differences in sensitivity? 17 Rodrigues et al. $IWHU�HVWDEOLVKLQJ�WKH�IDFH�VHQVLWLYLW\�SURͤOH�EDVHG�RQ�WKH�SDWLHQW̵V�UHSRUW��SURJ- UHVV�VKRXOG�EH�PDGH�ZLWK�WKH�REMHFWLYH�DVVHVVPHQW��,W�LV�QHFHVVDU\�WR�FRQͤUP�WKH� patient’s report, since changes, even if slight, may be present despite the patient not reporting complaints. In the objective assessment, it is necessary to perform procedures of the touch and nociceptive modalities, to stimulate different receptors DQG�QHUYH�ͤEHUV��7KH�WRXFK�PRGDOLW\�YHULͤHV�WKH�LQWHJULW\�RI�WKH�PHFKDQLFDO�IDFLDO� UHFHSWRUV�WKDW�LQYROYH�$ƌ�ͤEHUV��SHUIRUPLQJ�WKH�VWLPXODWLRQ�RI�WKH�0HUNHO�GLVF�DQG� WKH�5XIͤQL�FRUSXVFOH��UHVSRQVLEOH�IRU�GHWHFWLQJ�UDSLGO\�DQG�VORZO\�DGDSWLQJ�WRXFK� stimuli; and Meissner corpuscles and KDLU�IROOLFOH�ͤEHU, which are involved in the transduction of nerve signals. The nociceptive modality (perception of pain and WHPSHUDWXUH�� LV�QRW�PHGLDWHG�E\�WKH�UHFHSWRUV�RI�WKH�FRUSXVFOHV�VR�WKDW�WKH�$Ǝ� DQG�&�ͤEHUV�DUH�LQYROYHG�LQ�WKH�WUDQVPLVVLRQ�RI�WKHVH�VHQVRU\�PRGDOLWLHV4. Thus, in the case of touch stimulation, it is recommended, due to the frequency of use in the articles included and the ease of application, the Light touch/static light touch test and, consequently, the Mechanical detection threshold, which can also be per- IRUPHG�DFFRUGLQJ�WR�WKH�LQVWUXPHQW�XVHG�IRU�FKHFNLQJ��LI�PRQRͤODPHQWV�DUH�XVHG��� These tests will allow the stimulation of corpuscular receptors and stimulation of $ƌ�ͤEHUV4. For nociceptive stimulation, the use of the prick test or thermal stimu- lation is recommended. However, it is emphasized that for proper stimulation and central transmission of painful stimuli, cutaneous thresholds must be between 23g and 51g, and if thermal stimulation is used, temperatures below 0°C or above 47°C4. The tests are carried out with the patient with eyes closed, informing the applicator from which point the stimulation is perceived. In conclusion, The instruments for investigating facial sensitivity used in the clinic in cases of maxillofacial trauma involve, for subjective assessment: the patient’s report guided by structured questions; and for objective assessment: predominantly the evaluation of touch and nociceptive sensitivity, the latter also comprising ther- mal evaluation. From this, it is proposed a standardization to investigate changes in IDFLDO�VHQVLWLYLW\��%HVLGHV��WKH�VWXG\�RI�WKH�SURͤOH�RI�WKHVH�FKDQJHV�FRQWULEXWHV�WR�WKH� improvement of surgical techniques and to a safe return about the long-term results of the patient’s sensory situation14. Limitations It was not possible to carry out a meta-analysis of this systematic review because WKH�LQFOXGHG�VWXGLHV�GLG�QRW�KDYH�VXIͤFLHQW�TXDQWLWDWLYH�GDWD�IRU�UHJLVWUDWLRQ�LQ�FRQ- tingency tables. Also, they showed high qualitative heterogeneity in the aspects of nomenclature, procedures, and equipment used in the sensitivity objective assess- ment procedures. For this, more studies should investigate the validity of the tests used in practice, to favor the use of effective diagnostic procedures, since the accuracy analysis of the tests was not possible due to the low availability of data in the studies. CONFLICTS OF INTEREST STATEMENT No conflicts of interest exist. 18 Rodrigues et al. References 1. Bogusiak K, Arkuszewski P. Characteristics and epidemiology of zygomaticomaxillary complex fractures. J Craniofac Surg. 2010 Jul;21(4):1018-23. doi: 10.1097/scs.0b013e3181e62e47. 2. Lalloo R, Lucchesi LR, Bisignano C, Castle CD, Dingels ZV, Fox JT, et al. Epidemiology of facial fractures: incidence, prevalence and years lived with disability estimates from the Global Burden of Disease 2017 study. Inj Prev. 2020 Oct;26(Supp 1):i27-i35. doi: 10.1136/injuryprev-2019-043297. 3. Allareddy V, Allareddy V, Nalliah RP. Epidemiology of facial fracture injuries. J Oral and Maxillofac 6XUJ�������2FW����������������GRL����������M�MRPV�������������b 4. Siemionow M, Gharb BB, Rampazzo A. The Face as a sensory organ. Plast Reconstr Surg. �����)HE����������������GRL����������356��E���H����IHG�IG�b 5. Devine M, Hirani M, Durham J, Nixdorf DR, Renton T. Identifying criteria for diagnosis of post-traumatic pain and altered sensation of the maxillary and mandibular branches of the trigeminal nerve: a systematic review. Oral Surg Oral Med Oral Pathol Oral Radiol. �����-XQ����������������GRL����������M�RRRR�������������b 6. 6DLG�