1http://dx.doi.org/10.20396/bjos.v19i0.8659930 Volume 19 2020 e209930 Original Article 1 Head of the Department of Surgical Dentistry, Maxillofacial Surgery and Oncostomatology, Uzhhorod National University, Ukraine 2 Head of Scientific and Research Centre of Forensic Odontology, Department of Prosthetic Dentistry, Uzhhorod National University, Ukraine. Corresponding author: Myroslav Goncharuk-Khomyn Uzhhorod National University Universitetska 16/a st., Uzhhorod, Ukraine Area code: 88000 Phone number: 0991212813 E-mail address: myroslav. goncharuk-khomyn@uzhnu.edu.ua Received: June 04, 2020 Accepted: November 23, 2020 Economical treatment- related burden assessment of maxillofacial trauma among Ukrainians patients Pavlo Brekhlichuk1 , Myroslav Goncharuk-Khomyn2,* Aim: Quantitative evaluation of prognostic correspondence between initial maxillofacial traumatic injury assessed by facial injury severity score and maxillofacial injury severity score, treatment cost and duration of hospitalization among Ukrainian patients. Methods: Design of present study was retrospective and based on the medical data of patients hospitalized with signs of maxillofacial trauma. Quantitative assessment of maxillofacial trauma was held with the use of facial injury severity score (FISS) and maxillofacial injury severity score (MFISS). Average treatment cost and hospitalization duration were used as coordinative criteria for economical treatment- related burden verification. Results: Levels of correlation between FISS, treatment charges and hospitalization duration were r=0.69 (р<0.05) and r=0.67 (р<0.05) respectively, while analogical correlations for MFISS were 0.74 (р<0.05) and 0.69 respectively (р<0.05). Statistical correspondence between FISS and MFISS scores among study sample reached r=0.71 (р<0.05). Cases with milder maxillofacial trauma types, characterized with initial lower levels of FISS and MFISS scores, demonstrated greater degree of FISS-to-MFISS inter-relation compare to cases with severe maxillofacial trauma. Conclusion: Even though FISS and MFISS scores both demonstrated reliable levels of correlation with hospitalization duration and cost of dental rehabilitation after maxillofacial trauma injury, but MFISS approach characterized by prognostically greater level of statistical relationship with economically related treatment derivates. Moreover, differentiation capabilities of MFISS is relative greater than FISS, since independent grading of separate functional disabilities becomes possible. Keywords: Maxillofacial injuries. Treatment outcome. Cost of illness. Hospitalization. http://dx.doi.org/10.20396/bjos.v19i0.8659930 mailto:myroslav.goncharuk-khomyn@uzhnu.edu.ua mailto:myroslav.goncharuk-khomyn@uzhnu.edu.ua https://orcid.org/0000-0001-6754-5142 https://orcid.org/0000-0002-7482-3881 2 Brekhlichuk et al. Introduction Relevant predictive models of dental care supply, especially under the conditions of different insurance policies, should be based on the valid quantitative approaches aimed at primary differentiation and categorization of maxillofacial injuries in terms of needed dental interventions, their cost and treatment efficiency1-3. Nevertheless, most of the used insurance calculation protocols considering the fact of maxillofacial trauma and it’s situational parameters as main criteria for future prognosis regarding payments of claims2-5. Argumentative choice of economically-available and predic- tively-effective treatment modality could help to optimize overall rehabilitation pro- cess among maxillofacial trauma patients considering initial injuries of anatomical structures and associated functional alterations2,6,7. Rapid scoring protocol of maxillo- facial trauma also could provide further perspectives for primary patients categoriza- tion within trauma center conditions1,7,8. Due to the number of previously published studies it is argumentative to resume that maxillofacial injury severity scoring system (MFISS) and facial injury severity scor- ing system (FISS) are considered as ones of the most prevalent among research- ers’ use1,6,7,9-12, while in one of the studies such conclusion even was solidly clarified2. Taking into account original scoring methodologies of MFISS and FISS scores and available literature data on their use with research objective, the first one is considered to be more functionally-oriented, while second – anatomically-based1,2,6,7,9-11. On the other hand number of publications revealed that both of these scores demonstrated comparatively analogical statistical associations with treatment duration, rehabilita- tion charges, injury severity, complication rates and some other parameters1,2,7,10-12. In multicentered study of European Maxillofacial Trauma it was noted that even though FISS scores were relatively analogical by the mean values among different centers, the longest hospitalization durations were noted in Kiev (Ukraine)13. Since treatment meth- ods and primary post-traumatic care differ among different countries, even though such are following the same biological and medical principles, it is important to find out how the FISS and MFISS scores predictively relate with the regionally-specific eco- nomic burden parameters of hospitalization and rehabilitation, thus widening the per- spective of their use with an aim of dental care and insurance support optimization. Considering all above-mentioned facts, our research was aimed at the quantitative evaluation of prognostic correspondence between initial maxillofacial traumatic injury assessed by FISS and MFISS scores, treatment cost and duration of hospitalization among Ukrainian patients. Materials and methods Design of present study was retrospective and based on the medical data of patients hospitalized to the Uzhhorod City Clinical Hospital (Uzhhorod, Ukraine) with signs of maxillofacial trauma during 2015-2019. Study sample among all received patients’ data sets was formed due to the next inclusion criteria: 1) preliminary diagnosis of maxillofacial trauma provided at the time of hospitalization; 2) accessibility of full trauma characteristics description in provided medical documentation; 3) presence of supplemental X-ray diagnostics results or their full interpretations inside medical 3 Brekhlichuk et al. documentation; 4) availability of full description regarding provided treatment with exact postscript of hospitalization duration and cost of treatment. Exclusion criteria presented by the next parameters: 1) absence of necessary information related to the diagnostic process, anamnesis, provided treatment, cost or hospitalization dura- tion; 2) concomitant traumatic injury; 3) combined trauma with related head and neck, eye-ball injury or neurotrauma; 4) compromised anamnesis with allied somathopa- thologies that potentially could alter rehabilitation process14. Due to the inclusion and exclusion criteria group of 65 patients with maxillofacial trauma was formed. All patients were treated at the same accident and emergency department with further admission to the in-patient facility. Data extraction was provided considering anonymiza- tion and ethical principles with further analysis of only next parameters: age, gender, char- acteristics of trauma, duration of hospitalization, average treatment cost15. Average treat- ment cost was accounted by provisional monetary units due to the provided diagnostics complex, dental surgical rehabilitation, hospitalization and in-patient care without consid- ering cost of pharmacological support. Hospitalization duration was defined by the period between primary patient’s admission to the hospital till the official discharge2. Such crite- ria as average treatment cost and hospitalization duration were used as coordinative for economical treatment-related strain verification for each patient from study group2. Quantitative assessment of maxillofacial trauma was held with the use of facial injury severity score (FISS) and maxillofacial injury severity score (MFISS). Evaluation was pro- vided due to the original protocols of such scoring systems proposed by Bagheri et al. and Zhang et al. respectively6,9. Use of MFISS and FISS scores as comparable and referent for analytical prognosis considering average treatment cost and duration of hospitalization, was argumented by high level of such criteria correlation with expert maxillofacial injury evaluation, described in previous studies1,2,12. Assessment of FISS and MFISS scores was provided by two independent investigators (members of Scientific and Research Center of Forensic Odontology, Uzhhorod National University), who were previously calibrated with the use of reference data and characterized with inter-observer agreement of k=0.81. Design of provided study was previously approved by ethical committee of Faculty of Dentistry (Uzhhorod National University) as a part of the complex research related to the clinical and laboratorial assessment of advanced dental technologies and expert evaluation of treatment methods (Ethical Approval № 25072017-13). Exploratory data analysis principles were used for study sample characterization with the evaluation of above-mentioned criteria (age, gender, characteristics of trauma, dura- tion of hospitalization, average treatment cost). Univariative statistical analysis with estimation of mean, maximum and minimum was provided considering criteria of FISS and MFISS scores independently among study group patients. Pearson’s r was used for the estimation of correlation between FISS and MFISS scores and such parameters as average cost of treatment and hospitalization duration, while probability value (p-value) lower than 0.05 was considered as statistically reliable. Student’s t-test was used for assessment of statistical difference between MFISS and FISS criteria patterns among study group patients, and distinction trends of their relation to the average treatment cost and hospitalization duration16,17. Bland and Altman analysis was provided with XLSTAT 2020 software tool (xlstat.com)18,19. Stratification of data and its’ further graph- ical representation were provided via Microsoft Excel software (Microsoft Office, 2019). http://xlstat.com 4 Brekhlichuk et al. Results Distribution of maxillofacial trauma patients sample by the age and gender criterions was presented as following: out of 65 subjects 53 (81.54%) were males and 12 (18.46%) were females with ratio of 4.41:1; 18 persons (27.69%) were within age group of 20-30 years (mean age – 26.72 years), 37 (56.92%) – within age group of 30-40 years (mean age – 34.54 years), 10 persons (15.38%) – within age group of 40-50 years (mean age 46.31 years). Obtained distribution tendencies partially promoted by used specific inclusion criteria. Main causes of maxillofacial trauma among study sample were presented by interper- sonal violence (assaults) – 29 patients (44.62%), road-traffic accidents – 22 patients (33.85%), falls – 9 patients (13.85%), work-associated and sport-related – 5 patients (7.69%). Most cases of interpersonal violence, road-traffic accidents and work/ sport-related traumas as causes of maxillofacial trauma were registered among male patients (65.52%, 63.64% and 60.0% respectively), while most cases of falls (55.56%) were noted among females. Among all 65 analyzed cases 47 (72.30%) of them were presented with bone fractures (mandible fractures – 14 cases (21.54%), Le Fort I frac- tures – 5 cases (7.69%), Le Fort II fractures – 4 cases (6.15%), Le Fort III – 4 cases (6.15%), zygoma complex fractures – 6 cases (9.23%), nasal fractures – 10 cases (15.39%), orbital fractures – 4 cases (6.15%)), while in 18 cases (27.69%) such were also associated with pronounced adjacent soft tissue injuries (projected mostly at the lower one third of the face in 7 cases (10.77%), at the mid-face area – in 6 cases (9.23%), and at the upper one third – in 5 cases (7.69%), while in most cases lacera- tions projected beyond restricted area of some one third part of the face). Numerical results received during FISS and MFISS scoring were characterized with normal distribution pattern, which also was described in previous study1. Mean FISS score for study sample was 3.70±1.06 (mode – 3.0), while mean MFISS score was 16.37±6.04 (mode – 20) (Table 1). Average period of hospitalization duration was equal to 8.9±2.4 days. Table 1. FISS and MFISS scores statistical characteristic registered among study sample Variable Observations Obs. with missing data Obs. without missing data Minimum Maximum Mean Std. deviation FISS 65 0 65 1.000 6.000 3.708 1.057 MFISS 65 0 65 5.000 30.000 16.369 6.035 Levels of correlation between FISS, average treatment charges and hospitalization duration were r=0.69 (р<0.05) and r=0.67 (р<0.05) respectively, while analogical cor- relations for MFISS were 0.74 (р<0.05) and 0.69 respectively (р<0.05) (Table 2). Table 2. Correlation level between FISS, MFISS, hospitalization duration and cost of treatment Criteria Cost of treatment p-value Hospitalization Duration p-value FISS p-value FISS 0.69 р<0.05 0.67 р<0.05 1.0 р<0.05 MFISS 0.74 р<0.05 0.69 р<0.05 0.71 р<0.05 Statistical correspondence between FISS and MFISS scores among study sample reached r=0.71 (р<0.05) (Fig. 1). 5 Brekhlichuk et al. Without preliminary standardization of obtained data statistical difference was noted during pairwise comparison of FISS and MFISS results during analysis of 57 (87.69%) individual cases. Patients with FISS scores greater than 3 and MFISS scores greater than 10 were characterized with statistically longer period of hospitalization compare to study subjects with lower obtained scores levels (р<0.05). Results of Bland-Altman analysis considering relationship between FISS and MFISS scores represented on the Figures 2-4, with primary received data presented in Table 3. M FI S S FISS 35 30 25 20 15 10 5 0 0 21 3 4 65 7 Figure 1. Correlation between FISS and MFISS scores registered among study sample. 30 25 20 15 10 5 0 Bias Cl Bias (95%) Cl (95%) 0 62 4 8 10 12 16 1814 20 Figure 2. Bland-Altman plot for FISS and MFISS scoring results 6 Brekhlichuk et al. 30 25 20 15 10 5 0 D ife re nc e Mean Minimum/Maximum Figure 4. Correspondence between mean and median of FISS/MFISS due to the Bland-Altman analysis 0,08 0,07 0,05 0,06 0,03 0,04 0,02 0,01 0 0 105 15 Diference Diference Normal D en si ty 20 25 30 Figure 3. Distribution of differences in FISS/MFISS scores due to the normality assumption 7 Brekhlichuk et al. Table 3. Data received during Bland-Altman analysis of MFISS and FISS score Bias Standard error CI Bias (95%) Confidence interval (Differences): Lower Limit Upper Limit Lower Limit Upper Limit 12.66 5.33 11.33 13.98 2.19 23.12 Obtained results shown that both scores are analogically effective from the evaluation point of view and could be used for maxillofacial trauma assessment considering treatment expenses and hospitalization duration as targeted research parameters. But specific pattern of FISS/MFISS relationship was noted, due to which cases with milder maxillofacial trauma types, characterized with initial lower levels of FISS and MFISS scores, demonstrated greater degree of FISS-to-MFISS statistical inter-relation compare to cases with severe maxillofacial trauma. Discussion The variability of the maxillofacial traumatic lesions cases and the prevalence of such among able-bodied persons justify the need for investigation, development and improvement of expert evaluation approaches considering dental changes of primary traumatic and secondary iatrogenic origin13,20-22. In present research we have argument the correlational levels between obtained FISS/MFISS scores, which indirectly related to the anatomical and functional severity of maxillofacial trauma, and economical parameters of provided dental care in means of average treatment cost and hospital- ization duration. The results of previous analytical studies indicated the presence of relationship between the necessary amount of dental rehabilitation interventions and initial characteristics (location, severity, spread) of obtained dental injuries1,2,13,20. Due to the EURMAT project data the most prevalent causes of maxillofacial trauma were assault and falls13, while in our study most of trauma injuries were caused by interpersonal violence and road-traffic accidents. Falls and work-associated/sport-re- lated injuries were third and fourth the most prevalent causes of patients’ hospitaliza- tion with maxillofacial trauma. Analogically to EURMAT project data related to Ukraine, male/female ratio in our study also was characterized with predominant number of male patients compare to female (4.41:1), while overall European ratio was at level of 3.6 to 113. Similarly, to the findings noted by Siber et al. (2015)20, we have also reg- istered the bone injuries as the most prevalent among study sample of patients with maxillofacial trauma. Providing retrospective study Bocchialini and Castellani (2019) had found that increase of FISS score parameter by 1 point associated with the increase in hospitalization duration on 12% (1.44 days)23. More pronounced relationship between FISS score and length of hospital stay was described in Siregar et al. study (2019)24. Authors men- tioned that increase of FISS at the level of more than 3 characterized with 14 times more chances of longer hospitalization24. Under the conditions of retrospective study, it was found the FISS scores greater than 5 causing 18 times more chances to be hospitalized compare to the situations when FISS score was lower than 6, while FISS scores greater than 5 were also statistically associated with need of minimum 3 days hospitalization (P < 0.01)25. Other researchers highlighted that level of FISS≤3 was 8 Brekhlichuk et al. relevant for cases of maxillofacial trauma hospitalization up to 6 days, while FISS level of greater than 12 in most cases caused hospitalization for more than 10 days23. Bagheri himself as an author of FISS scoring system mentioned that even though such demonstrated statistical association with the hospitalization duration, but it could not be categorized as fully reliable predictor9. In his research 3 cases of death were highlighted, while non-survivors’ FISS scores were not statistically different from those registered among survivors9. Nevertheless, in all above-mentioned lethal cases victims demonstrated FISS scores greater compare to average ones noted during analysis9. Considering variability of FISS/MFISS scores and hospitalization duration, we could not register some specific pattern of correspondence between 1 FISS/ MFISS point increase and additional number of days with needed in-patient care, but it was found that FISS scores greater than 3 and MFISS scores greater than 10 asso- ciated with more prolonged period of hospitalization compare to situations with lower obtained scores levels, difference between which was statistically approved (р<0.05). Analogical to our, study was provided also by Ramalingam S. (2015), who have found out that both MFISS and FISS scores were characterized with relatively equal correla- tion due to the cost (r=0.862 and r=0.845 respectively) and duration of hospitaliza- tion (r=0.828 and r=0.819) among Indian population2. Considering such results author highlighted the role of MFISS and FISS as “economic burden” indices, while in our study FISS demonstrated lower correlation levels with duration of hospitalization and the cost of treatment2. The presence of analogical study gives us a unique possibility to analyze potential causes of obtained results dissimilarities. Such could be provoked by the influence on next factors: different approaches of patients stratification in India and in Ukraine; different calibration levels of dental experts, who provided the evalu- ation of patients regarding MFISS and FISS criteria; different distribution of costs for specific dental trauma treatment algorithm in India and Ukraine; variances of national currency due to the standardized cost of dental treatment calculated by insurance companies in means of provisional monetary units; differences of samples sizes. Analogical to our findings, such also were described in Giriyan et al. (2019) study, in which authors had registered Spearmen’s correlation levels of r=0.398 and r=0.429 between MFISS/FISS values and treatment cost respectively, and correlation levels of r=0.477 and r=0.433 between MFISS/FISS values and hospitalization time respec- tively12. While estimated levels of correlation were lower compare to those in Ramalin- gam’s study2, they were statistically approved. Similarly to previous study, it was found that in cases of mid-face fracture among Chinese population MFISS and FISS scores represent statistically analogical interrelations with hospitalization duration – r=0.415 and r=0.464 respectively26. Moreover, authors found out statistically reliable depen- dencies between FISS scores and gender, age, etiology and fracture type parameter, while MFISS scores demonstrated connection with gender at the p=0.201 and with age at p=0.052. Nevertheless, MFISS and FISS scores correlated between themselves at r=0.0592 (p=0.01)26. In our study relationship between above mentioned parame- ters (gender, age, etiology and fracture type) were out of primary formulated objective, while they will be considered as a perspective for future research It is interesting to note that in the comparative study of different maxillofacial trauma grading approaches, FISS scores demonstrated the lowest level of correlation with 9 Brekhlichuk et al. expert evaluation results (r=0.699), while MFISS demonstrated the greatest (r=0.801) among all studied scoring systems1. Despite that FISS scores were characterized by statistically the highest interrelation pattern with the cost of operation (r=0.742), while correlation levels of FISS (r=0.620) and MFISS (r=0.636) scores were comparable due to the operation time parameter1. Our results are partially consistent with those described by Chen et al. (2014)1 in terms, that in our study MFISS scores also have shown the highest level of correlation not only with duration of hospitalization, but also with the average cost of treatment. Originally FISS was described as anatomically-based by the methodology of calcu- lation in many of previously published studies1,2,7,10-12, but considering specific cate- gorization of such grading trauma system, we could resume that this criteria is also partially functionally-oriented, even if such traumatic functional association is not so directly represented, as in MFISS methodology. For example, Le Fort III fracture gains greater score than Le Fort I or Le Fort II, which is logical, because such fracture is causing greater anatomical disruption, but it should be noted that Le Fort III fracture is also associated with more pronounced functional alterations. So, we would pro- pose to classify FISS scoring system as “predominantly anatomically-oriented”, rather than just “anatomically-based”. Considering today’s progress in maxillofacial surgery and forensic dentistry new scor- ing systems for maxillofacial trauma evaluation still developing. Canzi and colleagues described comprehensive facial injury (CFI) score, which differs by high descriptive capacity and with this characteristic supports patient differentiations in trauma cen- ters27,28. Potentially CFI could be used as statistical tool for hospitalization duration prog- nosis. Another perspective could be related to the use of novel CBCT-superimposition principle, which is effective for objectification of all possible dental status changes29. Based on the obtained results we can resume that both FISS and MFISS scores are reliable baseground parameters that could be effectively used for prediction of treat- ment cost and duration of hospitalization, as component parts included in non-lin- ear insurance proceedings calculation. Greater correlation level of MFISS compare to FISS could be argumented by the orientation of such grading approach not only on the anatomical, but also on the functional evaluation of maxillofacial alterations. Limitations of provided study related to its retrospective design, considering the use of medical patients records as primary data source, which related with risk of possi- ble documentational errors. But such limitation was partially overcome by inclusion into study sample only cases with available X-ray diagnostic results or at least with their complete description (interpretation). Other limitation of the research is related to the relatively small study sample compare to the analogical studies provided pre- viously. On the other hand, such situation could be argumented by the use of spe- cific exclusion criteria, such as concomitant traumatic injury, combined trauma with related head and neck, eye-ball injury or neurotrauma and compromised anamne- sis with allied somathopathologies. Neglect of such criteria potentially could help to increase the primary size of study sample, but in such situation, we would be limited in possibility to make reliable conclusion considering connection between FISS and MFISS scores with specifically maxillofacial trauma characteristics. Logically, that inclusion of patients with combined or concomitant trauma or aggravated anam- 10 Brekhlichuk et al. nesis would complicate statistical analytical approach, and deviates from originally formulated objective. Nevertheless, even considering above-mentioned limitations, obtained results demonstrated analogical pattern of relationship between FISS/ MFISS scores and economically associated rehabilitation parameters. Moreover, ver- ified covariances could be categorized as quantitively specific for Ukrainian patients. The perspective of future study includes the statistical representation of such indices in the form of correction coefficients incorporated in the equations of the insurance indemnity amount calculation, which could be used not with ad hoc aim, but with prospective objective. Considering limitations of provided retrospective study it could be resumed that even though FISS and MFISS scores both demonstrate reliable levels of correlation with hospitalization duration and average cost of dental rehabilitation after maxillofacial trauma injury, but MFISS approach characterized by prognostically greater level of statistical relationship with economically related treatment derivates. Moreover, differ- entiation capabilities of MFISS is relative greater than FISS, since independent grading of separate functional disabilities become possible. 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