1 Volume 22 2023 e231640 Original Article Braz J Oral Sci. 2023;22:e231640http://dx.doi.org/10.20396/bjos.v22i00.8671640 1 Department of Community Dentistry, São Paulo State University (Unesp), School of Dentistry, Araraquara, São Paulo, Brazil. 2 University of Florida, College of Dentistry, Gainesville, Florida, United States of America. 3 Department of Clinical & Community Sciences, University of Alabama, Birmingham, Alabama, United States of America. Corresponding author: Elaine Pereira da Silva Tagliaferro Department of Community Dentistry, São Paulo State University (Unesp), School of Dentistry, Araraquara Rua Humaitá, 1680, Centro - 14801-903 - Araraquara, SP, Brazil Tel: +55 16 3301-6343 FAX: +55 16 3301-6343 elaine.tagliaferro@unesp.br Editor: Altair A. Del Bel Cury Received: Dec 5, 2022 Accepted: Jan 13, 2023 Evidence-practice gap in treatment decisions about defective composite and amalgam restorations among Brazilian dentists Elaine Pereira da Silva Tagliaferro1* , Joseph L. Riley III2 , Gregg H. Gilbert3 , Silvio Rocha Correa da Silva1 , Fernanda Lopez Rosell1 , Aylton Valsecki Junior1 , Valeria Veiga Gordan2 Aim: Better understanding of dentists’ decision-making about defective restorations is needed to close the evidence-practice gap (EPG). This study aimed to quantify the EPG about defective restorations and identify dentist factors associated with this EPG. Methods: 216 dentists from São Paulo State, Brazil, completed a questionnaire about three clinical case scenarios involving defective composite restorations with cementum-dentin margins (case 1) and enamel margins (case 2), and an amalgam (case 3) restoration. Dentists were asked what treatment, if any, they would recommend, including preventive treatment, polishing, re-surfacing, or repairing the restoration, or replacing the entire restoration. Replacing the entire restoration in any of these three scenarios was classified as inconsistent with the evidence, comprising an EPG. Bivariate analyses using Chi-square, ANOVA, or multiple comparison tests were performed (p<.05). Results: for defective composite restorations, 49% and 55% of dentists chose to replace the entire restoration for cases 1 and 2, respectively. Twenty-nine percent of dentists chose to replace the entire amalgam restoration. Dentists were significantly more likely to choose to replace the defective amalgam restoration than the composite restoration with a defect at the cementum-dentin margins or the enamel margins (both at p < .001). Female dentists were more likely to choose a conservative treatment than male dentists for cases 1 (p=.034) and 2 (p=.009). Dentists with a higher percentage of patients interested in individualized caries prevention were also more conservative in case 1 (p=.045). Conclusion: a substantial EPG  regarding treatment decisions for defective restorations exists, especially for composite restorations. This study adds to the international evidence that an EPG exists in this clinical area and that global strategies need to be developed to close the gap. Keywords: Dental caries. Practice patterns, dentists’. Dental restoration repair. https://orcid.org/0000-0001-6225-6915 https://orcid.org/0000-0003-1815-975X https://orcid.org/0000-0003-2017-625X https://orcid.org/0000-0002-0227-8896 https://orcid.org/0000-0002-6270-9168 https://orcid.org/0000-0002-1776-0925 https://orcid.org/0000-0003-0381-5996 2 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 Introduction Although clinical research is designed to benefit clinical practice, systematic reviews have demonstrated across a wide range of health care fields that it is common for there to be a substantial gap between what clinical evidence says should be occurring and what is actually done in everyday clinical practice1. This gap is referred to as the “evidence-practice gap (EPG)”2. In dental care, operative dentistry procedures com- prise a large percentage of the care provided, so closing the EPG in this area presum- ably has substantial potential to improve patient outcomes and reduce costs. One component of operative dentistry, the treatment of defective dental restorations, is particularly salient with regard to the EPG. Defective dental restorations are very common in dental practice3. Contemporary recommendations for decision-making about deteriorating restorations have suggested monitoring, refurbishment, and repair as the first choice, and considering replacement only when less invasive approaches are not appropriate4. Studies have shown that most dentists choose repair as a treatment decision for defective restorations. Almost all German dentists reported performing repairs, espe- cially when treating defective composite restorations5. More than 80% of Swiss den- tists reported repair of composite, ceramic, or crown restorations; over half of them repair metal and amalgam restorations6. Most (87%) Greek dentists reported repairing defective restorations7. On average, about 72% of dentists reported performing repairs, according to a recent systematic review and meta-analysis8, which also observed that higher percentages of repairs were reported in more-recent studies. Engaging clinicians in research networks can be a means to move evidence into rou- tine practice9. Responding to hypothetical clinical case scenarios as part of a large questionnaire study, 65% of dentists in the United States and Scandinavia Dental Practice-Based Research Network (DPBRN) chose to replace a composite restoration with a defective margin on dentin and 35% chose to replace an amalgam restoration10. A total of 52% of Japanese dentists chose to replace a composite restoration with a defective margin on dentin11. Replacing the entire restoration in these scenarios is inconsistent with the current evidence, constituting an EPG. There is a scarcity of recent studies from Brazil about the existence of an EPG regard- ing treatment decisions for defective restorations. In an investigation of the adherence of treatment decisions to the International Caries Consensus Collaboration recom- mendations, a majority (69%) of dentists and students chose only to polish amalgam restorations that had no compelling need for replacement12. Therefore, our objective for the current study is to quantify the EPG about defective restorations and identify dentist factors associated with this EPG among Brazilian dentists. Material and Methods Study design and ethical aspects This cross-sectional study was based on a questionnaire evaluating the treatment preferences of dentists regarding defective restorations. The research was approved 3 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 by an Ethical Review Board (protocol number 78/11). It was undertaken with each subject’s understanding and written consent and according to the World Medical Association Declaration of Helsinki principles. Participants Participating dentists were from Araraquara, a municipality with 233,744 inhabitants, located in the Central Region of São Paulo State, Brazil. At the time of study planning (2011), 722 dentists from Araraquara were registered at the Regional Council of Den- tistry. For data collection (2014-2015), we updated the list of dentists by consulting inter- net sources, and we mailed paper questionnaires to 801 dentists. The following strate- gies were used to increase response rate: pre-paid return envelope, questionnaires sent to work address; a second copy of the questionnaire to non-respondents; pre-contact by telephone; a collection of completed questionnaires at work address13. Inclusion criteria were dentists who currently practice in Araraquara and treat dental caries. Measures Dentists completed an enrollment/demographic questionnaire that provided demo- graphic data and information about their clinical training and individual practices (see Table 1). Using the same questionnaire completed by American and Japanese DPBRN dentists (10,11), dentists were presented with three clinical case scenar- ios that included high-resolution photographs of a defective restoration. The first clinical case scenario had a defective composite restoration with cementum-dentin margins and a description of a patient who had been a regular dental patient and had existing dental restorations. A second case had a defective composite resto- ration with enamel margins and a description of a patient at low caries risk. A third case had a defective amalgam restoration and a description of the same patient at low caries risk. Respondents were asked to recommend a treatment for each case scenario. Treatment choices were as follows: a) No treatment today, follow the patient regularly, b) Instruct patient in plaque removal for the affected area, c) Use of in-office fluoride, d) Use of a prescription fluoride, e) Recommend a non-prescription fluoride, f) Use sealant or unfilled resin over the tooth, g) Use of chlorhexidine rinse, h) Polish, re-surface, or repair restoration, i) Replace entire restoration. Scenarios, photographs, and response codes for the possible treatments are shown in Table 2. Table 1. Dentist and practice characteristics Characteristic Percentage (n) or Mean (SD) Age of dentist 42.2 (12.0) Gender (female) 61% (n=131) Type of practice Private practice 56% (n=121) Private/public hybrid 20% (n=44) Public health 22% (n=47) Other 2% (n=4) Continue 4 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 Continuation Years since dental school graduation 19.7 (SD=11.7) Type of dental school graduation Public institution 76% (n=165) Private institution 24% (n=51) Specialization Did not complete specialization training 38% (n=82) Specialization training 62% (n=134) Post-graduate degree No advanced degree 69% (n=149) Master’s degree 7% (n=14) Doctorate 24% (n=53) Percent of patients by age cohort Pediatric patients (missing=2) 23% (SD=26) Adults (19-44 years) (missing=2) 34% (SD=18) Adults (45-64 years) (missing=2) 30% (SD=17) Adults (65 years and older) (missing=2) 13% (SD=11) Percent of patients for which a dental explorer is used to diagnose an occlusal caries lesion. 79% (SD=32) Assess caries risk for individual patients (missing=9) 36% (n=75) Percent of patients interested in a caries prevention regimen (missing=1) 44% (SD=26) Percent of patients who receive a caries risk prevention regimen (missing=2) 56% (SD=35) Note: 216 dentists completed at least one of the three clinical scenarios. Table 2. Treatment choices for clinical cases scenarios No treatment Prevention Repair Replacement Preliminary patient description. The patient is a 30-year old female with no relevant medical history. She has no complaints and is in your office today for a routine visit. She has been attending your practice regularly for the past 6 years. Case scenario 1 (cementum-dentin margins). The patient has 5 existing restorations and is not missing any teeth. Indicate what treatment you would provide to the restoration shown by the arrow in the first picture on the left. [Reprinted from Ericson et al., 2003 with permission]* ---- 9% (n=19) 41% (n=88) 50% (n=108)a Continue 5 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 Continuation Case scenario 2 (enamel margins). Now imagine the patient has no other dental restorations than the one shown, no dental caries, and is not missing any teeth. Indicate what treatment you would provide to the restoration. [Reprinted from Mjör and Toffenetti, 2000, with permission]** 3% (n=7) 13% (n=28) 28% (n=61) 55% (n=119)a Case scenario 3 (amalgam restoration). The same patient has no other dental restorations than the one shown, no dental caries, and is not missing any teeth. Indicate what treatment you would provide to the restoration. Courtesy of Dr. Ivar Mjör. 27% (n=57) 7% (n=14) 38% (n=80) 29% (n=61)b Treatment choices: a) No treatment today, follow the patient regularly, b) instruct patient in plaque removal for the affected area, c) In-office fluoride, d) Prescription fluoride, e) Recommend non-prescription fluoride, f) Use sealant or unfilled resin over tooth, g) Chlorhexidine treatment, h) Polish, re-surface, or repair restoration, but not replace, i) Replace entire restoration. Responses were grouped as follows: No treatment category (a,b), Prevention (c-g), Repair (h), Replace (i). a Case scenarios 1 and 2 were completed by 215 dentists. b Case scenario 3 was completed by 212 dentists. *Ericson D, Kidd E, McComb D, Mjör I, Noack MJ. Minimally Invasive Dentistry - concepts and techniques in cariology. Oral Health Prev Dent. 2003;1(1):59–72. **Mjör IA, Toffenetti F. Secondary caries: a literature review with case reports. Quintessence Int. 2000 Mar;31(3):165–79 Statistical analysis First, descriptive statistics were calculated for all study variables. Responses to the clinical case scenarios comprised the main outcome of interest and were grouped as follows: 1- No treatment category: a) No treatment today, follow the patient reg- ularly; b) Instruct patient in plaque removal for the affected area); 2- Prevention: c) Use of in-office fluoride; d) Use of a prescription fluoride; e) Recommend a non-prescription fluoride; f) Use sealant or unfilled resin over the tooth; g) Use of chlorhexidine rinse; 3- Repair: h) Polish, re-surface, or repair restoration; 4- Replace: i) Replace entire restoration. The treatment assignment that was considered the most aggressive code when multiple codes were indicated (i.e., no treatment < prevention, repair < replace) was coded as the primary treatment choice. Replacing the entire restoration in any of these three scenarios was classified as inconsistent with the evidence, comprising an EPG. To examine differences in treatment choices across the three clinical case scenar- ios, Friedman’s test for ordinal data was performed. Associations between treatment 6 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 decisions and dentist and practice variables were tested by bivariate analysis using chi-square tests when explanatory variables were categorical and ANOVA and multi- ple comparison tests when explanatory variables were continuous. Exploratory multi- variate models using Generalized Linear Modeling were used to test for associations between treatment decisions and dentist and practice variables. Results Sample characteristics A total of 216 dentists completed at least one of the three clinical scenarios on the questionnaire. The mean age for participating dentists was 42.2 years. As shown in Table 1, most dentists were female (61%), worked exclusively in private prac- tice (56%), received their dental school training from a public dental school (76%), had some specialization (62%) and no post-graduate degree (69%), and treated patients between 19-64 years of age. On average, they had 19.7 years since dental school graduation. Regarding their practices, as shown in Table 1, only 36% reported assessing caries risk, 44% of their patients were interested in a caries prevention regimen, and 56% of their patients received a caries risk prevention regimen. Differences between clinical case scenarios The Wilcoxon Signed Rank test indicated a significant difference across the three sce- narios (X2 (2) = 56.436, p =< .001). The mean ranks for each case were as follows: Clinical Scenario 1 (cementum-dentin margins) = 2.18), Clinical Scenario 2 (enamel margins) = 2.16, and Clinical Scenario 3 (amalgam restoration) = 1.66. The Wilcoxon Signed Rank test indicated that scenario 1 and 2 did not differ (Z = -.400, p = .842), however scenario 3 differed significantly from scenario 1 (differ (Z = -7.260, p < .001) and scenario 2 (Z = -6.449, p < .001). Clinical case scenario 1 For the first clinical case scenario that involved a defective composite restoration with cementum-dentin margins (Table 2), no dentists chose the “no treatment” option, 9% (n=19) selected various methods of prevention, 41% (n=88) chose to polish, re-surface, or repair the restoration, and 50% (n=108) elected to replace the entire restoration. For this case (Table 3), female dentists were significantly more likely to choose a more-conservative treatment than male dentists (p = .034). In addition, dentists who chose to replace the entire restoration had a significantly lower percentage (p = .045) of patients interested in individualized caries prevention (39%) than dentists who chose to polish, re-surface, or repair (48%). 7 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 Table 3. Clinical case scenario #1 - defective composite restoration with cementum-dentin margins Variable No Treatment n=0 Prevention 9% (n=19) Repair 41% (n=88) Replace 50% (n=108) P-value Percent or mean (SD) Percent or mean (SD) Percent or mean (SD) Percent or mean (SD) Gender of dentist Male (n=85) --- 7% (n=6) 32% (n=27) 61% (n=52) .034 Female (n=130) --- 10% (n=13) 47% (n=61) 43% (n=56) Years since graduation 21.2 (10.6) 19.7 (11.6) 19.4 (12.1) .828 Type of School graduation Public (n=165) --- 10% (n=16) 37% (n=61) 53% (n=88) .097 Private (n=50) --- 6% (n=3) 54% (n=27) 40% (n=20) Specialization Yes (n=134) --- 10% (n=8) 47% (n=38) 43% (n=35) .276 No (n=81) --- 8% (n=11) 37% (n=50) 55% (n=73) Post-graduate degree Yes (n=53) --- 9% (n=5) 42% (n=22) 49% (n=26) .974 No (n=162) --- 9% (n=14) 41% (n=66) 51% (n=82) Practice model Private practice exclusively (n=120) --- 7% (n=8) 47% (n=56) 47% (n=56) .115 Public health with some private practice (n=95) --- 12% (n=11) 34% (n=32) 55% (n=52) Primarily pediatric patients a Yes (n=25) 20% (n=5) 36% (n=9) 44% (n=11) .118 No (n=188) 7% (n=14) 42% (n=79) 51% (n=97) Assess Patient’s Caries Risk b Yes (n=75) 11% (n=8) 41% (n=31) 48% (n=36) .802 No (n=131) 8% (n=11) 40% (n=52) 52% (n=68) Use of explorer to examine caries at the margin of an existing restoration 78% (33.4) 81% (31) 77% (32) .728 Percent of patients interested in Individualized Caries Prevention c 44% (19) 48% (27)* 39% (24)* .045 Percent of patients receiving Individualized Caries Prevention d 63% (36) 56% (34) 53% (35) .514 Two hundred and fifteen dentists completed clinical case scenario 1. a Two dentists did not indicate the percentage of their patients that are pediatric. b Nine dentists did not indicate whether or not they assess caries risk. c One dentist did not indicate the percentage of their patients that were interested Individualized Caries Preventions. d Two dentists did not indicate the percentage of their patients that were interested Individualized Caries Preventions. * Indicates percentages were different at p < .05. Clinical case scenario 2 For the second clinical case scenario that involved a defective composite restoration with enamel margins (Table 2), the “no treatment” option was chosen by 3% (n=7) of the dentists, 13% (n=28) selected various methods of prevention, 28% (n=61) chose 8 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 to polish, re-surface, or repair the restoration, and 55% (n=119) elected to replace the entire restoration. For this case (Table 4), female dentists were significantly more likely to choose a more-conservative treatment than male dentists (p = .009). Table 4. Clinical case scenario #2 - defective composite restoration with enamel margins Variable No Treatment 3% (n=7) Prevention 13% (n=28) Repair 28% (n=61) Replace 55% (n=119) P-value Gender of dentist Male (n=85) 7% (n=6) 7% (n=6) 25% (n=21) 61% (n=52) .009 Female (n=130) 41% (n=1) 17% (n=22) 31% (n=40) 52% (n=67) Years since graduation 21.2 (10.6) 19.7 (11.6) 18.1 (12.1) 20.5 (11.4) .603 Type of school graduation Public (n=165) 4% (n=6) 14% (n=23) 29% (n=47) 54% (n=89) .794 Private (n=50) 2% (n=1) 10% (n=5) 28% (n=14) 60% (n=30) Specialization Yes (n=134) 2% (n=3) 13% (n=18) 25% (n=33) 60% (n=80) .246 No (n=81) 5% (n=4) 12% (n=10) 35% (n=28) 48% (n=39) Post-graduate degree Yes (n=53) 2% (n=1) 13% (n=7) 30% (n=16) 55% (n=29) .920 No (n=162) 4% (n=6) 13% (n=21) 28% (n=45) 56% (n=90) Practice model Private practice exclusively (n=120) 3% (n=4) 13% (n=15) 25% (n=30) 59% (n=71) .601 Public health with some private practice (n=95) 3% (n=3) 14% (n=13) 33% (n=31) 51% (n=48) Primarily pediatric patients (50% or greater) a Yes (n=25) 0% (n=0) 24% (n=6) 32% (n=53) 44% (n=11) .200 No (n=188) 4% (n=7) 11% (n=22) 28% (n=8) 57% (n=108) Assess Patient´s Caries Risk b Yes (n=75) 0% (n=0) 17% (n=13) 29% (n=22) 53% (n=40) .202 No (n=131) 4% (n=5) 11% (n=14) 28% (n=37) 57% (n=75) Use of explorer to examine caries at the margin of an existing restoration 89% (24) 83% (27) 76% (34) 77% (32) .655 Percent of patients interested in Individualized Caries Prevention c 36% (20) 41% (28) 44% (26) 44% (26) .828 Percent of patients receiving Individualized Caries Prevention d 31% (32) 53% (36) 55% (34) 58% (35) .240 Two hundred and fifteen dentists completed clinical case scenario 2. a Two dentists did not indicate the percentage of their patients that are pediatric. b Nine dentists did not indicate whether or not they assess caries risk. c One dentist did not indicate the percentage of their patients that were interested Individualized Caries Preventions. d Two dentists did not indicate the percentage of their patients that were interested Individualized Caries Preventions. Clinical case scenario 3 For the third clinical case scenario that involved a defective amalgam restoration (Table 2), the “no treatment” option was chosen by 27% (n=57) of the dentists, 7% (n=14) selected various methods of prevention, 38% (n=80) chose to polish, re-sur- 9 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 face, or repair the restoration, and 29% (n=61) elected to replace the entire restoration. For this case (Table 5), the type of dental school attended was significantly associated with the treatment recommendation (p=.021): dentists who attended a private dental school were more likely than public dental school graduates to polish, re-surface, or repair the restoration as compared to public school graduates. Also, dentists with a specialization were significantly more likely (p=.019) to replace the defective resto- ration as compared to those without a specialization, who were more likely to polish, re-surface, or repair the restoration (Table 5). Table 5. Clinical case scenario #3 - defective amalgam restoration Variable No treatment 27% (n=57) Prevention 7% (n=14) Repair 38% (n=80) Replace 29% (n=61) P-value Percent or mean (SD) Percent or mean (SD) Percent or mean (SD) Percent or mean (SD) Gender of dentist Male (n=84) 24% (n=20) 11% (n=9) 38% (n=32) 27% (n=23) .246 Female (n=128) 29% (n=37) 4% (n=5) 38% (n=48) 30% (n=38) Years since graduation 19.7 (10.6) 22.1 (12.2) 17.3 (12.1) 22.3 (11.7) .072 Type of school graduation Public (n=162) 30% (n=49) 7% (n=11) 32% (n=52) 31% (n=50) .021 Private (n=50) 16% (n=8) 6% (n=3) 56% (n=28) 22% (n=11) Specialization Yes (n=133) 27% (n=36) 9% (n=12) 31% (n=41) 33% (n=44) .019 No (n=79) 27% (n=8) 3% (n=3) 49% (n=39) 22% (n=11) Post-graduate degree Yes (n=52) 27% (n=14) 4% (n=2) 35% (n=18) 35% (n=18) .617 No (n=160) 27% (n=43) 8% (n=12) 39% (n=62) 27% (n=43) Practice model Private practice exclusively (n=120) 25% (n=30) 8% (n=10) 43% (n=51) 24% (n=29) .150 Public health with some private practice (n=92) 29% (n=27) 4% (n=4) 32% (n=29) 35% (n=32) Primarily pediatric patients (50% or greater) a Yes (n=24) 25% (n=6) 8% (n=2) 29% (n=7) 38% (n=9) .685 No (n=187) 27% (n=51) 6% (n=12) 39% (n=73) 27% (n=52) Assess Patient´s Caries Risk b Yes (n=72) 28% (n=20) 8% (n=6) 32% (n=23) 32% (n=23) .600 No (n=131) 27% (n=36) 5% (n=7) 40% (n=53) 27% (n=36) Use of explorer to examine caries at the margin of an existing restoration 75% (33) 86% (26) 76% (34) 83% (27) .408 Percent of patients interested in Individualized Caries Prevention c 43% (26) 50% (37) 42% (25) 45% (24) .690 Percent of patients receiving Individualized Caries Prevention d 53% (34) 61% (39) 53% (36) 60% (33) .610 Two hundred twelve dentists completed clinical case scenario 3. a Two dentists did not indicate the percentage of their patients that are pediatric. b Nine dentists did not indicate whether or not they assess caries risk. c One dentist did not indicate the percentage of their patients that were interested Individualized Caries Preventions. d Two dentists did not indicate the percentage of their patients that were interested Individualized Caries Preventions. 10 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 Discussion In this study, we assessed treatment decisions about defective restorations and quantified the EPG. Because at least some respondents recommended replacing the entire restoration for each of the three scenarios, we can state that an EPG exists for each scenario. The results suggest that dentists are more concordant with the evidence when man- aging defective amalgam restorations than when managing composite restorations. A minority (29%) of dentists reported that they would replace a defective amalgam restoration, as compared to approximately half who stated that they would choose the same procedure for defective composite restorations. These results align with Gordan et al.10 but are less conservative for composite restorations than dentists from other countries. Most German5, Swiss6, Japanese11, and Norwegian14 dentists chose to repair defective composite restorations instead of replacing them. Amalgam has been the most-used dental material among Brazilian dentists15,16. As a low-cost and effective material, amalgam remains the first choice for dentists in some developing countries17. However, it is important to mention that measures to gradually reduce the use of mercury, including amalgam in dentistry, have been pro- posed globally. The Minamata Convention on Mercury is a global treaty established by The United Nations Environment Program to protect human health and the environment from the adverse effects of mercury. It proposes the adoption of some measures such as “a ban on new mercury mines, the phase-out of existing ones, the phase-out and phase-down of mercury use in a number of products and processes, control measures on emissions to air and on releases to land and water, and the regulation of the infor- mal sector of artisanal and small-scale gold mining. The Convention also addresses interim storage of mercury and its disposal once it becomes waste, sites contaminated by mercury as well as health issues.” The Convention was agreed on 2013 but entered into force only in 201718. Brazil signed the Minamata Convention in 2013, and since Jan- uary/2019, ANVISA has prohibited the manufacturing, marketing, and use of mercury elements and unencapsulated amalgam alloy in health services19. Irrespective of material used, damage to dental restorations is common and can be expected due to the oral environment’s adverse conditions20. As a contemporary minimally invasive (MI) management, repair of restorations instead of their replace- ment can be a feasible and effective way of managing defective restorations21. Before repairing and replacing restorations within the MI concept, dentists should consider refurbishment with no new restorative material inserted, such as eliminating over- hangs and discoloration, re-contouring, smoothing, or polishing the surface and sealing small gaps with sealants22. Repair is another essential element of MI man- agement. It conserves tooth structure and vitality, reduces patient chairside time, alle- viates dental anxiety, increases the longevity of the existing restoration, and presents reduced cost, materials, and staff time3. A recent systematic review demonstrated that clinical longevity of defective direct restorations treated by MI procedures, such as repair, seal, and refurbishment, is the same as replaced restorations, indicating the MI techniques should be the first choice for defective restorations23. Therefore, den- tists should consider postponing restoration replacement until no other preventive or restorative treatment is available21 in recovering the esthetic and function. 11 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 Our study assessed the association between treatment decisions and dentist/ practice characteristics. Female dentists chose conservative treatment for com- posite restorations more frequently than males. Other studies have also observed a more-conservative approach to caries management24-26 and patients’ oral health care27 among female dentists as compared to their male counterparts. Dentists who chose to replace the entire defective composite restoration had lower percentages of patients interested in individualized caries prevention than dentists who chose to polish, re-surface, or repair. A possible reason for such a finding is that the patient’s interest in preventive oral health may require a more-preventive approach during dental care28 and the adoption of shared decision-making in a patient-centered care model29. Although there was an association between type of school, specialization, and treatment decision for defective amalgam restorations in the current study, this does contrast with findings from other studies. Other Brazilian studies have suggested that students from private dental schools are less-conservative in caries management than those from pub- lic schools12,30. These findings might be partially explained by the fact that better-pre- pared undergraduate students are selected by the admission process in Brazilian public dental schools31 when compared to private dental schools. Our results have also shown that dentists who had a specialty degree were less conservative in deciding a treatment for an amalgam defective restoration. Previous DPBRN studies did not have the “spe- cialization” as a variable, but we would speculate that participant dentists who had a specialty degree were more used to esthetic or prosthetic procedures and not as much with procedures more accepted in general dental practice. Therefore, they were more likely to replace defective amalgam restorations by other restorative materials. Studies on diagnosis and treatment decisions for carious lesions have shown that more-expe- rienced dentists32 and dentists with post-graduate degrees reported a more-conserva- tive approach in caries management33. Future studies with a larger sample and at the national level should be designed to augment the findings of the current study. The findings from the current study represent the treatment decisions of a sam- ple of dentists who predominantly graduated in public schools and had specialized training. Considering the minority of Brazilian dental schools teach MI, caries lesions sealing or other essential elements of MI34, our current findings are consistent with that circumstance. The limitations of this study consist of a) the cross-sectional design; b) a sample with a self-selected group of dentists; and c) the assumption that dentists reported accurately what they do in their dental practices26. As a strength, the questionnaire was confirmed to be a viable tool to assess and compare dental practice among other populations of dentists35. Conclusion A substantial EPG  regarding treatment decisions for defective restorations exists, especially for composite restorations. This study adds to the international evidence that an EPG exists in this clinical area and that global strategies need to be developed to close the gap. 12 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 Data Availability Datasets related to this article will be available upon request to the corresponding author. Acknowledgements Financial support was provided by the Foundation for the Development of the São Paulo State University (FUNDUNESP; Grant 0170/004/13-PROPe/CDC) and by The São Paulo Research Foundation (FAPESP; Grant 2012/10397-2). Certain components of this work were supported by National Institutes of Health grants U01-DE-16746, U01-DE-16747, U19-DE-22516, and U19-DE-28717. Opinions and assertions contained herein are those of the authors and are not to be construed as necessarily representing the views of the respective organizations or the National Institutes of Health. NIDCR had no role in the study design, data collection, analysis, publishing decision, or manuscript preparation. The authors thank André Luis Faria e Silva, Claudia Huck, Fabiano Jeremias, Juliana Alvares Duarte Bonini Campos, Mariana de Matos, Luana Moreira Loures Ridolfi, Wilson Chediek, Elina Mara da Silva Marcomini, Rita De Cassia Prando, Márcia Santana, Luis Alberto da Silva, Ivanete Correa Macieira, Célia Regina de Freitas Rocha, Olavo Bergamaschi Barros and Kar- ina Antunes for their assistance and dentists who participated in this study. Conflict of Interest The authors declare no conflict of interest. Authors Contribution EPST, JLR, GHG, SRCS, FLR, AVJ and VVG have made substantial contributions to conception and design of the study. EPST collected the data; EPST, JLR, GHG and VVG analyzed and interpreted the data. EPST, JLR, GHG, SRCS, FLR, AVJ and VVG have been involved in drafting the manuscript, revising it critically and have given final approval of the version to be submitted. References 1. Cochrane LJ, Olson CA, Murray S, Dupuis M, Tooman T, Hayes S. Gaps between knowing and doing: understanding and assessing the barriers to optimal health care. J Contin Educ Health Prof. 2007 Spring;27(2):94-102. Doi: 10.1002/chp.106. 2. Elliott JH, Turner T, Clavisi O, Thomas J, Higgins JP, Mavergames C, et al. Living systematic reviews: an emerging opportunity to narrow the evidence-practice gap. Plos Med. 2014 Feb;11(2):e1001603. Doi: 10.1371/journal.pmed.1001603. 3. FDI. World Dental Federation. Repair of restorations: : Adopted by the General Assembly: September 2019, San Francisco, United States of America. Int Dent J. 2020 Feb;70(1):7-8. Doi: 10.1111/idj.12552. 4. Wilson N, Lynch CD, Brunton PA, Hickel R, Meyer-Lueckel H, Gurgan S, et al. Criteria for the Replacement of Restorations: Academy of Operative Dentistry European Section. Oper Dent. 2016 Sep;41(S7):S48-S57. Doi: 10.2341/15-058-O. 13 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 5. Kanzow P, Hoffmann R, Tschammler C, Kruppa J, Rödig T, Wiegand A. Attitudes, practice, and experience of German dentists regarding repair restorations. Clin Oral Investig. 2017 May;21(4):1087-93. Doi: 10.1007/s00784-016-1859-3. 6. Kanzow P, Dieckmann P, Hausdörfer T, Attin T, Wiegand A, Wegehaupt FJ. Repair restorations: questionnaire survey among dentists in the Canton of Zurich, Switzerland. Swiss Dent J. 2017 Apr 10;127(4):300-11. 7. Maria A, Charikleia P, Panagiotis L. Attitudes of Greek dentists towards repair of conservative restorations. An online survey. Int Dent J. 2017 Dec;67(6):351-9. Doi: 10.1111/idj.12319. 8. Kanzow P, Wiegand A, Göstemeyer G, Schwendicke F. Understanding the management and teaching of dental restoration repair: Systematic review and meta-analysis of surveys. J Dent. 2018 Feb;69:1-21. Doi: 10.1016/j.jdent.2017.09.010. 9. Gordan VV. How to Bridge Research Results to Everyday Clinical Care? Oper Dent. 2017 Jan/Feb;42(1):1-9. Doi: 10.2341/16-154-B. 10. Gordan VV, Garvan CW, Richman JS, Fellows JL, Rindal DB, Qvist V, et al. How dentists diagnose and treat defective restorations: evidence from the dental practice-based research network. Oper Dent. 2009 Nov-Dec;34(6):664-73. Doi: 10.2341/08-131-C. 11. Kakudate N, Yokoyama Y, Sumida F, Matsumoto Y, Yamazaki H, Touge T, et al. Evidence-practice gap in minimal intervention dentistry: Findings from a dental practice-based research network. J Dent. 2020 Nov;102:103469. Doi: 10.1016/j.jdent.2020.103469. 12. Sales GC, Marques MG, Rubin DR, Nardoni DN, Leal SC, Hilgert LA, et al. Are Brazilian dentists and dental students using the ICCC recommendations for caries management? Braz Oral Res. 2020 Jun;34:e062. Doi: 10.1590/1807-3107bor-2020.vol34.0062. Erratum in: Braz Oral Res. 2020;34:e062err. 13. Tagliaferro EPS, Ridolfi LML, Matos M, Rosell FL, Valsecki Junior A, Silva SRC, et al. [Translation and Brazilian adaptation of the “Assessment of caries diagnosis and caries treatment questionnaire”] Arq odontol. 2017;53:1-15. Portuguese. 14. Staxrud F, Tveit AB, Rukke HV, Kopperud SE. Repair of defective composite restorations. A questionnaire study among dentists in the Public Dental Service in Norway. J Dent. 2016 Sep;52:50-4. Doi: 10.1016/j.jdent.2016.07.004. 15. Lins AS, Ishikiriama Á, Rizzante FAP, Furuse AY, Mondelli J, Ishikiriama SK, et al. Use of restorative materials for direct and indirect restorations in posterior teeth by Brazilian dentists. RSBO. 2014;11(3):238-44. 16. Da Silva Pereira RA, da Silva GR, Barcelos LM, Cavalcanti KGBA, Herval ÁM, Ardenghi TM, et al. Practice-based analysis of direct posterior dental restorations performed in a public health service: Retrospective long-term survival in Brazil. Plos One. 2020 Dec;15(12):e0243288. Doi: 10.1371/journal.pone.0243288. 17. Worthington H V, Khangura S, Seal K, Mierzwinski-Urban M, Veitz-Keenan A, Sahrmann P, et al. Direct composite resin fillings versus amalgam fillings for permanent posterior teeth. Cochrane Database Syst Rev. 2021 Aug;8(8):CD005620. Doi: 10.1002/14651858.CD005620.pub3. 18. The United Nations Environment Programme. The Minamata Convention on Mercury is a global treaty to protect human health and the environment from the adverse effects of mercury. [cited 2022 Apr 4]. Available from: https://www.mercuryconvention.org/en/about. 19. Anvisa - National Health Surveillance Agency. Brazil. [News: Anvisa prohibits mercury and powder for amalgam alloy used in dentistry]. 2018 Dec 19 [cited 2022 Apr 18]. Available from: https://aps.saude.gov.br/noticia/4954. Portuguese. 20. Blum IR, Özcan M. Reparative Dentistry: Possibilities and Limitations. Curr Oral Health Rep. 2018;5(4):264-9. Doi: 10.1007/s40496-018-0191-1. 14 Tagliaferro et al. Braz J Oral Sci. 2023;22:e231640 21. Blum IR. The Assessment and minimally invasive management of existing restorations. Dent Update. 2020 Nov;47(10):823-8. 22. Blum IR. Restoration Repair as a Contemporary Approach to Tooth Preservation: Criteria for Decision Making and Clinical Recommendations. Prim Dent J. 2019 May;8(1):38-42. Doi: 10.1308/205016819826439466. 23. Martins BMC, Silva EJNLD, Ferreira DMTP, Reis KR, Fidalgo TKDS. Longevity of defective direct restorations treated by minimally invasive techniques or complete replacement in permanent teeth: a systematic review. J Dent. 2018 Nov;78:22-30. Doi: 10.1016/j.jdent.2018.09.001. 24. Gordan VV, Garvan CW, Heft MW, Fellows JL, Qvist V, Rindal DB, et al. Restorative treatment thresholds for interproximal primary caries based on radiographic images: findings from the Dental Practice-Based Research Network. Gen Dent. 2009 Nov-Dec;57(6):654-63; quiz 664-6, 595, 680. 25. Kakudate N, Sumida F, Matsumoto Y, Manabe K, Yokoyama Y, Gilbert GH, et al. Restorative treatment thresholds for proximal caries in dental PBRN. J Dent Res. 2012 Dec;91(12):1202-8. Doi: 10.1177/0022034512464778. 26. Riley JL 3rd, Gordan VV, Rouisse KM, mcclelland J, Gilbert GH; Dental Practice-Based Research Network Collaborative Group. Differences in male and female dentists’ practice patterns regarding diagnosis and treatment of dental caries: findings from The Dental Practice-Based Research Network. J Am Dent Assoc. 2011 Apr;142(4):429-40. Doi: 10.14219/jada.archive.2011.0199. 27. Yusuf H, Tsakos G, Ntouva A, Murphy M, Porter J, Newton T, et al. Differences by age and sex in general dental practitioners’ knowledge, attitudes and behaviours in delivering prevention. Br Dent J. 2015 Sep;219(6):E7. Doi: 10.1038/sj.bdj.2015.711. 28. Tagliaferro EPS, Silva SRC, Rosell FL, Valsecki Junior A, Riley III JL, Gilbert GH, et al. Methods for caries prevention in adults among dentists from a brazilian community. Brazilian J Oral Sci. 2020 Feb;19:e206624. Doi: 10.20396/bjos.v19i0.8656224. 29. Lee H, Chalmers NI, Brow A, Boynes S, Monopoli M, Doherty M, et al. Person-centered care model in dentistry. BMC Oral Health. 2018 Nov 29;18(1):198. Doi: 10.1186/s12903-018-0661-9. 30. Bervian J, Tovo MF, Feldens CA, Brusco LC, Rosa FM da. Evaluation of final-year dental students concerning therapeutic decision making for proximal caries. Braz Oral Res. 2009 Jan-Mar;23(1):54-60. Doi: 10.1590/s1806-83242009000100010. 31. Morita MC, Uriarte Neto M, Fontanella VRC, Haddad AE. The unplanned and unequal expansion of Dentistry courses in Brazil from 1856 to 2020. Braz Oral Res. 2020 Nov;35:e009. Doi: 10.1590/1807-3107bor-2021.vol35.0009. 32. Geibel MA, Carstens S, Braisch U, Rahman A, Herz M, Jablonski-Momeni A. Radiographic diagnosis of proximal caries-influence of experience and gender of the dental staff. Clin Oral Investig. 2017 Dec;21(9):2761-70. Doi: 10.1007/s00784-017-2078-2. 33. Chana P, Orlans MC, O’Toole S, Domejean S, Movahedi S, Banerjee A. Restorative intervention thresholds and treatment decisions of general dental practitioners in London. Br Dent J. 2019 Oct;227(8):727-32. Doi: 10.1038/s41415-019-0849-7. 34. Sampaio FC, Rodrigues JA, Bönecker M, Groisman S. Reflection on the teaching of cariology in Brazil. Braz Oral Res. 2013 May-Jun;27(3):195-6. Doi: 10.1590/S1806-83242013000300001. 35. Tagliaferro E, Valsecki Junior A, Rosell FL, Silva S, Riley JL, Gilbert GH, et al. Caries diagnosis in dental practices: results from dentists in a brazilian community. Oper Dent. 2019 Jan/Feb;44(1):E23-E31. doi: 10.2341/18-034-C.