Oral rehabilitation with complete implant-supported dental prosthesis: a budget impact analysis from the unified health system perspective


 Background Tooth loss is an important measure of a population's health condition and has a significant impact on people's quality of life. Oral rehabilitation is an important means for functional and social recovery of edentulous patThe aim of the study was to estimate the budget impact of complete implant-supported dental prostheses in the rehabilitation of mandibular edentulism in patients within the context of the Unified Health System (Sistema Único de Saúde – SUS).Methods Treatment with complete implant-supported dentures was compared with the technology most frequently used - Conventional Complete Dental Prosthesis. For analysis we adopted the Methodology proposed by the Methodological Guidelines for Budget Impact Analysis of the Brazilian Network for Health Technology Assessment (REBRATS). Sensitivity analysis was performed per scenarios and a temporal horizon of 5 years was used.Results Implementation of treatment by complete implant-supported dental prostheses would demand an amount of US$ 970,253,019.00 in 5 years in the reference scenario, US$ 545,767,323.40 in the most optimistic scenario, and US$ 1,516,020,342.40 in the worst scenario.Conclusions These results could support the Brazilian managers in planning the Federal budget destined to Medium to High Complexity (treatments), making it possible to disseminate rehabilitative treatment performed with complete implant-supported dentures in SUS, and serve as reference for health systems in other countries.


Conclusions
These results could support the Brazilian managers in planning the Federal budget destined to Medium to High Complexity (treatments), making it possible to disseminate rehabilitative treatment performed with complete implant-supported dentures in SUS, and serve as reference for health systems in other countries. 3 Background In 2004, the Federal Government of Brazil launched the national oral health policy "Nacional de Saúde Bucal" -(PNSB) [1], which contemplated expansion of the offer of specialized dental assistance services. This led to Brazil offering its citizens universal oral health care services right from prevention through to their rehabilitation. As from the introduction of the PNSB, the financial resources destined for oral health have increased progressively, including treatments of medium complexity, by means of the implementation and financing of Dental Specialty Centers -"Centros de Especialidades Odontológicas" -(CEOs) and regional Dental Prosthesis Laboratories -"Laboratórios Regionais de Próteses Dentárias" -(LRPDs) [2,3].
In spite of this advancement, the National Health Survey conducted in 2013 showed evidence that the accumulation of oral diseases over the course of years without support for treatment resulted in a high demand for oral prosthetic rehabilitation in the population [4]. Sixteen million Brazilians do not even have one single tooth in the mouth. Mandibular edentulism affects an even higher number of people, and is prevalent in 31.23% of the adults, and in 67.29% of elderly people as from the age of 60 years. The reality is no different in the state of São Paulo which, in spite of being the richest in the country, has elderly people with a high mean number of teeth extracted [25.87%], of whom 37.27% need complete mandibular dental prosthesis [5].
In view of the high prevalence of the edentulism in Brazil, in 2004, the Ministry of Health (MH) started financing Conventional Complete Dental Prostheses (CCP), and in 2010 Complete implant-supported prostheses (CISP), for oral rehabilitation of edentulous patients [6,7]. Among these, the CISP is recognized as the type that offers patients a better fit in cases of edentulous mandibles [8][9][10].
However, this measure was not effectively adhered to by the CEOs of Brazil. According to data from the 1st cycle of PMAQ-CEO, conducted in 2014, only 1.8% if the CEOs in Brazil had professionals working in the area of implant dentistry. This demonstrated that although there are regulations governing payment, a political movement is necessary to drive the offer of mandibular implant-supported dentures. Recently, the MH stipulated that the CEOs that had not implemented the service previously, must now request the MH to have them implemented, technical and budget analysis [11], denoting ministerial concern about questions of allocating financial resources.
The high cost of providing oral health care services has been recognized worldwide, above all when the intention was to assist the population by means of complete oral rehabilitation [12,13]. Considering that financial resources are limited, it is important for them to be use efficiently to provide a basis for the decision-making process of public policies. In this context, economic evaluation studies may help to guarantee efficiency, especially by prioritizing attendance of patients requiring dentures among the demands on the available resources [12].
Among the economic analyses in health, the purpose of the Budget Impact Analysis (BIA) is to identify which would be the financial consequences arising from the incorporation of a certain technology into a health system with a certain budget, by revealing the feasibility of this incorporation for users of the system. The BIA constitutes a fundamental tool for public health budget managers, to help with budget prediction in a defined time interval [14].
Although PNSB has made advances since its creation up to the time of its operationalization, the present scenario point out persistent challenges that are strongly bound to questions of financing. In this context, the aim of this study was to evaluate the budget impact pf the use of complete implant-supported dental prostheses (CISP) in comparison with treatment with conventional complete dental prostheses (CCP) in rehabilitative treatment of mandibular edentulism, within the context of the Brazilian national health system -SUS.

Study Design
We designed a Budget Impact Analysis in accordance with the Methodological Guidelines of the Methodological Guidelines for Budget Impact Analysis of the Brazilian Network for Health Technology Assessment (REBRATS) [14] and with the presupposition of gradual diffusion of oral rehabilitation by means of CISP on two implants.
The presupposition of gradual diffusion was determined, because although there is an expectation that more effective technologies will be rapidly incorporated into clinical practice, this limitation must be recognized, particularly within the context of SUS.
Diverse variables could interfere in the process of diffusion of a technology, such as for example, training and qualification of human resources, in addition to the culture itself of the patients [14].

Technologies
The CISP on two implants has been pointed out as being the minimum treatment indicated for the rehabilitation of patients with edentulous mandibles [8][9][10]. Nevertheless, the CCP is the treatment most frequently offered as the proposal for rehabilitation in SUS, and continues to be routinely used in dental clinical practice because of its low cost [15].

Perspective
We adopted the perspective of the Federal Management of the Brazilian National Health System -SUS (Ministry of Health of Brazil).

Discount Rate and Time Horizon
We applied no discount rate and adopted the horizon of 5 years, starting in 2020 through to 2024, as recommended in the Guidelines of REBRATS [14].

Costs
Federal government financing incentive was assumed for the incorporation of substitutive rehabilitation by means of implant-supported dental prostheses, from the perspective of the Federal manager. The method for collecting cost data was based on the top-down, or macro costing approach, and was obtained from the table of SIGTAP -system for management of the table of procedures, medications and OPM of SUS "Sistema de Gerenciamento da Tabela de Procedimentos, Medicamentos e OPM do SUS" [16]. These are presented in Table 1 in US dollars (Year 2019).

Population of Interest
To predict and eligible population and the need for total investments to increase the diffusion of rehabilitative treatment of edentulous mandibles in SUS we combined epidemiological information, estimates of participation of the population and treatment costs.
The eligible population for treatment with CISP in our study was the same as that for CCP and concerned edentulous mandibles. In Brazil, this condition affects approximately 23 million persons of all age groups, but particularly the elderly [4].
In view of this high prevalence, initially and in the temporal horizon of 5 years, it must be admitted that large scale implementation of CISP is not feasible for 100% of those affected by the condition, for budget reasons.
Starting with this reality, we considered that for analysis from the perspective of the Ministry of Health, calculation of the population of interest by the method of demand found was more appropriate for helping with decision making [14].
In 2017, a total of 162,105 Complete Mandibular dental prostheses were approved in Brazil [17]. This means that this demand exists in the country. From these data, we were able to predict an approximate demand of 900,000 edentulous mandibular patients to be attended over the course of 05 years [temporal horizon of the analysis] in the SUS.
Initially, therefore, this would be the eligible population. However, some presuppositions were considered. One of these was that there were contraindications relative to the surgical procedure for implant placement. These limitations included smoker patients, those with some cardiovascular disorders, the use of certain medications and some systemic pathologies [18]. Secondly, we needed to consider that some patients might simply not wish to go through the surgical procedure required. Added to this, there is still the fact that in Brazil, the offer of services included in the public health and private system. So that it was a common occurrence for patients who had economic resources to choose to have treatments they considered more complex performed in the private system.
Within this context, we presupposed that only 30% of the total number of patients initially foreseen would fit into the profile of the target population. Considering the initial calculation, we predicted a demand of 270,000 to be attended by means of implant supported prosthesis on two implants, in five years.
According to this reasoning, in the new scenario proposed, the patients who met the criteria for rehabilitation with CISP would receive the new treatment, and the remainder would receive CCP.

Reference Scenario and Analysis per Scenarios
The reference scenario of the Budget Impact Analysis considered that all of the 900,000 patients would be rehabilitated with CCPs, while in the scenario proposed, the 270,000 patients eligible for rehabilitation with CISP would receive this treatment and the remainder would be rehabilitated with CCP, as illustrated in Fig. 1. Furthermore, in the period of the temporal horizon, it was considered that there would be no increase in the   [19]. By maintaining this value fixed for 5 years, we would have a total of US$ 326,787,958,074.12. Therefore, the budget impact corresponded to 0.29% of the total budget in the reference scenario, 0.46% in the most pessimistic scenario, and 0.16% in the most optimistic scenario.

Discussion
The Ministry of Health foresees Federal transfers to enable the municipalities to offer oral rehabilitation by means of CISP [6]. Budget impact analyses are becoming increasingly necessary to subsidize decision-making in health, and are routine practice in various countries [20]. In SUS, which foresees the offer of universal and integral care, and which has a limited budget, these analyses are even more important. In both the National Policy for Management of Technology in Health, and in Law12.401/11, Brazil reveals the importance of economic evaluation studies and recommends that budget impact studies should be conducted as support for decisionmaking in SUS [21,22].
In both the reference and alternative scenarios, the values found allowed us to affirm that implementation of the adoption of rehabilitation by means of CPIS was feasible. The technique is considered the best alternative for patients with edentulous mandibles. This indicated the need for adequate planning and management of the budget and government actions to allow the rational use of resources available for public oral health. The protocol for rehabilitation of edentulous mandibles in SUS, for example, must be reviewed.
The Federal manager offers financial transfers for encouraging the municipalities to offer implant dentistry services, however, considering the opposite need by the municipal manager, the dissemination of dental implants in the country has been slow. There is also the demand for qualified professionals for treatment with CISP. In this context, in addition to financial investments, political incentive in the spheres of management and education of human resources is imperative for use and dissemination of the technology.
One of the principles of SUS that makes economic analysis of the incorporation and dissemination of a certain technology imperative is Universality. The prevalence of mandibular edentulism in the Brazilian population is high, affecting 23 million persons of all ages, a continuing residue of the absence of oral health care over the course of years [4,23]. Therefore, offering all edentulous patient CIPS may be unfeasible, due to the financial limitations of the budget. Assuming this reality was necessary for designing the BIA based on the demand found instead of on epidemiology. This fact corroborates the need for investment in policies, such as "Brasil Sorridente" (Smiling Brazil), to prevent perpetuation of scenarios of lack of care and prove their inversion.
Relative to the use of the two technologies in SUS, we observed extensive reports in the literature with regard to the difficulty of adaptation to the CCP in the mandible [8][9][10]24].
Nevertheless, no data were found in SUS about the rate of abandonment of these dentures; that is, there are no estimates of how many patients undergo treatment and do not use the denture, which may be considered a waste of resources from the perspective of SUS as the payer, and would be an important datum to be considered in economic analyses.
Rehabilitation of edentulous patients by means of CISP had a significant effect on the quality of life, when compared with rehabilitation by means of CCP [25]. This change in quality is related to functional improvement, nutritional status and perception of oral health [26,27]. Improvement in the ingestion of nutritive foods by rehabilitated patients may have effects outside of dental treatment, improving the recovery of general health of patients. CISP is the most cost-effective treatment for rehabilitation of patients with edentulous mandibles even when analyzed from the perspective of the public health manager [28] and its dissemination will lead to more benefits to the population. Moreover, it would contribute to avoiding unnecessary expenses with conventional dental prostheses that will be used by the patients. In this sense, the technology deserves to be This study used parameters of values arising from a cost-effectiveness study and has the same limitations, such as The precise estimate of costs of rehabilitation by means of CISP versus CCP [28]. Because of the perspective of the Federal Manager adopted, the calculations were based on the

Ethics approval and consent to participate
Our data study comes from public databases and it was exempted from consideration by a research ethics committee.

Figure 1
Illustration showing the difference between the present scenario and the proposed scenarios, considering the temporal horizon of five years.