Knowledge of dental practitioners regarding Molar incisor hypo-mineralization: a systematic review and meta-analysis

Abstract

Molar incisor hypo-mineralization (MIH) is a qualitative developmental enamel defect involving one or more molars that may affects the incisors simultaneously. The present study examines the awareness of dentists regarding to MIH and compiles the existing studies in the form of a systematic review and meta-analysis. The research was conducted in the form of a secondary study, with a systematic search of texts until March 2026 in the databases of Scopus, Web of Science, and PubMed. Articles were selected based on eligibility criteria and finally the search results were reported in the PRISMA chart. The quality of the studies was assessed based on the Joanna Briggs Institute (JBI) checklist. The extracted information was entered in 18 Stata software. Heterogeneity was assessed using Q-Cochran square test, 12statistic. Egger tests were used to detect diffusion bias. After removing the duplicate articles and checking the titles, abstracts and full texts of the articles, 20 articles were subjected to quality assessment. Finally, 18 articles were entered into meta-analysis According to statistical results, the awareness of all dental practitioners regarding the recognition of MIH and prevalence of MIH was 79% (95% confidence interval [CI]:0.71–0.86) and 23% (95%CI: 0.17–0.30) respectively. The awareness of all practitioners about etiologic factors of MIH such as “genetics” 59%(95%CI:0.49–0.69), “chronic diseases"59% (95%CI:0.47–0.71), “acute diseases” 52%(95%CI:0.43–0.62), “antibiotic use” 51%(95%CI0.42-0.61), “environmental contaminations” 37% (95%CI:0.28–0.45) and “fluoride exposure” 15%(95%CI:0.10–0.21) were assessed. The results of the present study showed that the knowledge of different practitioners in diagnosis, prevalence and etiology of MIH is variable.

Introduction

Molar Incisor Hypo-mineralization (MIH) was introduced by Weehejiim in 2001 and recognized as a distinct disease by the European Academy of Pediatric Dentistry in 2003 (Weerheijm 2004). MIH, also known as cheese molars, non-fluoride enamel opacities, and internal enamel hypoplasia, is a qualitative developmental defect of enamel with a systemic origin. It typically occurs in one or more permanent first molars that may affects the incisors simultaneously (Dian et al. 2022; Alanzi et al. 2018). There are reports of involvement of second molars and primary canines, which can indicate an increased risk for MIH in the permanent dentition system (Serna-Muñoz et al. 2020).

The clinical manifestation of MIH presents a wide spectrum of lesions, ranging from opaque white to yellow-brown. As a result of the formation of demineralized enamel, affected teeth are more prone to dental sensitivities and caries after eruption (Alanzi et al. 2018).

The etiology of this condition is unknown, and various factors such as environmental and genetic factors or medical problems can contribute to its occurrence (Gunay 2023). The prevalence of MIH varies in different studies from 2.2% to 44% (Hamza et al. 2021; Kalkani et al. 2016).

MIH creates numerous challenges for both children and dentists. Children with MIH are 10 times more likely to undergo dental treatments, consequently experiencing increased anxiety and behavioral issues. MIH is a condition strongly associated with numerous clinical dental problems, including elevated dental sensitivity and an increased risk of caries progression. The affected enamel often exhibits a susceptibility to fracture under normal occlusal forces, a phenomenon known as post-eruptive breakdown (PEB). Furthermore, MIH presents various challenges for both the patient and the dental professional, such as difficulties in achieving profound anesthesia, compromised bond strength of restorative materials to the hypo-mineralized enamel, increased complexity of treatment protocols, and significant aesthetic concerns, particularly when anterior teeth are involved. Consequently, MIH is widely recognized as a major challenge in contemporary dentistry, having a considerable detrimental impact on the oral health and quality of life (OHRQoL) of affected individuals. (Kalkani et al. 2016).

Late diagnosis of MIH and subsequent severe tooth destruction have been reported as the second most common cause of permanent first molar extraction (Karkoutly et al. 2022). All these factors, alongside the aesthetic problems of incisors, necessitate a wide range of treatments. Obstacles such as behavioral control difficulties in children, challenging anesthesia, and poor bonding of dental materials to these teeth are other problems dentists encounter (Wall and Leith 2020).

Early diagnosis by dentists is the essential first step in its management, which typically follows a recommended six-step protocol: risk identification, early diagnosis, remineralization, caries prevention, restoration or extraction, and the maintenance phase (Jälevik and Klingberg 2002, 2011; Lygidakis 2010; Pitiphat et al. 2014). Assessing global awareness among dental practitioners regarding MIH is therefore critical for promoting timely diagnosis and effective management.

The first study on the awareness of pediatric dentists (PDs) regarding MIH was conducted in Europe in 2003, where most dentists reported MIH as a common and difficult clinical condition in terms of diagnosis and treatment. Based on this study, similar research has been carried out in countries such as Australia, Iran, Malaysia, and more recently, Saudi Arabia and the UK (Alanzi et al. 2018).

Environmental factors such as maternal illnesses during pregnancy, antibiotic or drug use in the last trimester, hypoxia during birth, and febrile illnesses in early childhood have been proposed as potential contributors to MIH (Gómez-Clavel et al. 2023; Gamboa et al. 2018), although other evidence shows no clear association between maternal illness and MIH risk (Skaare et al. 2021). Dentists report several challenges in managing MIH, including achieving sufficient anesthesia in highly sensitive teeth, managing child behavior, and choosing appropriate restorative materials (Hamza et al. 2023). Many also believe that the prevalence of MIH is increasing, highlighting the need for more research into its diagnosis, treatment, and etiology (Delgado et al. 2022; Yehia et al. 2021; Ghanim et al. 2011). Clinically, yellow-brown defects are most commonly noted, partly because white MIH lesions are often difficult to differentiate from other enamel defects such as fluorosis, enamel hypoplasia, and amelogenesis imperfecta; this diagnostic challenge is even greater in communities with high caries rates (Sajadi et al. 2021; Elhennawy et al. 2021; Elshiekh 2023; Hussein et al. 2014; Silva and Manton 2016).

Studies show varying levels of awareness among general dentists (GDs), PDs, and dental students regarding the prevalence, etiology, clinical manifestation, and treatment plan adopted for MIH. The present study aims to assess dentists’ awareness of MIH and to synthesize existing research through a systematic review and meta-analysis.

Materials and methods

This secondary study aimed to systematically review the awareness of dentists regarding MIH using cross-sectional studies. This study approved by ethics committee of Isfahan University of medical sciences (IR.MUI.DHMT.REC.1403.132) and has a Prospero ID of CRD420251119530.

Search strategy

All articles published up to March 2026 related to dentists’ awareness of MIH were extracted through a comprehensive and systematic search in the PubMed, Scopus, and Web of Science databases. Knowledge on prevalence, differential diagnose and etiologic factors of MIH in different group of dentists including GDs, PDs and all dental practitioners (ADPs) was compared. ADPs refer to dentists of any specialty who were included in the study.

To measure dentists’ awareness of MIH causes, participants were asked multiple‑choice questions covering eight possible etiological factors. These factors included genetics, acute and chronic illnesses in the mother or fetus, the use of medications and antibiotics, environmental pollution, and high levels of fluoride.

The search was conducted using standardized keywords from the MeSH database, combined with “AND” and “Or” operators. The terms, words, and combinations of words were generally searched as follows:

(“Dentists“[Mesh] OR “General Practice, Dental“[Mesh] OR “Pediatric Dentistry“[Mesh] OR “Students, Dental“[Mesh] OR dentist*[tiab] OR “dental practitioner*“[tiab] OR “general dentist*“[tiab] OR “general dental practitioner*“[tiab] OR “dental clinician*“[tiab] OR “oral health professional*“[tiab] OR “pediatric dentist*“[tiab] OR “paediatric dentist*“[tiab] OR pedodontist*[tiab] OR “dental specialist*“[tiab] OR “dental student*“[tiab]) AND (“Molar Hypomineralization“[Mesh] OR “Dental Enamel Hypomineralization“[Mesh] OR Developmental Defects of Enamel“[Mesh] OR “Molar Incisor Hypomineralization“[tiab] OR Molar-Incisor Hypomineralization“[tiab] OR “Molar Incisor Hypomineralisation“[tiab] OR Molar-Incisor Hypomineralisation“[tiab] OR MIH[tiab] OR “incisor molar hypomineralization“[tiab] OR “incisor molar hypomineralisation“[tiab] OR “demarcated opacity“[tiab] OR “demarcated opacities“[tiab]) AND (knowledge[tiab] OR awareness[tiab] OR perception*[tiab] OR attitude*[tiab] OR practice*[tiab] OR preparedness[tiab] OR competence[tiab] OR confidence [tiab] OR education[tiab] OR training[tiab] OR experience[tiab])

The electronic search method followed the clinical question (PECO):

• P: dental practitioners.

• E: Assessment of dentists’ awareness about MIH.

• C: Not applicable in this study.

• O: knowledge.

To retrieve all relevant information, no restrictions were applied to the time frame or geographical scope of the search.

After completing the search and importing the results into reference management software (Endnote X7, Thompson, Reuters, New York, NY), duplicate articles were automatically removed by the software. The final updated search was conducted in March 2026. The critical appraisal has been performed using the Joanna Briggs Institute (JBI) checklists for observational study designs, and the reporting structure has been aligned with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines.

Article selection

Following the database search, the titles and abstracts of all retrieved studies were independently screened by two researchers to identify and exclude irrelevant and duplicate articles. This initial screening was performed manually, without the use of specialized software or online tools. The inter-rater reliability for article selection at the abstract screening stage was assessed at 89% using Cohen’s Kappa statistic, indicating substantial agreement.

Subsequently, the full texts of the articles that passed the initial screening were retrieved and independently reviewed by the same two researchers against the predefined inclusion and exclusion criteria. At this stage, the agreement between the researchers was calculated at 91%, also assessed using Cohen’s Kappa statistic, signifying excellent agreement.

Any discrepancies arising between the two researchers during both the abstract and full-text review stages were resolved through discussion. If consensus could not be reached, a third senior researcher adjudicated the final decision.

To further ensure comprehensive identification of relevant studies, a manual search was conducted. This involved searching Google Scholar, consulting with subject matter experts, and meticulously examining the reference lists of the finally selected articles. Regarding the manual search on Google Scholar, we employed the following search string to identify relevant studies: (“Molar Incisor Hypomineralization” OR MIH) AND (“dental practitioners” OR “dentists”) AND (“knowledge” OR “awareness”) up to March 2026.

Inclusion criteria

Articles were included and selected if they (1) were cross-sectional studies, (2) assessed dentists’ awareness of MIH using a valid questionnaire, and (3) were published in English or Persian with accessible abstracts and full texts.

Exclusion criteria

1. Case reports, reviews, editorials, or abstracts lacking the required results.

2. Duplicate studies.

3. Studies that did not use valid tools to assess dentists’ awareness of MIH.

Quality assessment of articles and sources (scoring method)

The quality of the selected studies was evaluated based on the JBI critical appraisal checklist for cross-sectional studies. According to this checklist, the study’s objective, the accuracy of the study group selection, control of confounding factors, participant participation rate, data collection method, statistical analysis methods, and results of each study were independently criticized by two researchers. In case of disagreement between the two researchers, consensus was reached through discussion with a third person.

The JBI checklist for cross-sectional studies includes 8 items, with 4 options for each item: yes, no, unclear, not applicable. Each study was assigned a score from 0 to 8 based on the presence of the above items. Finally, the scores of the articles were summed, and studies with a score above 6 were classified as “good quality,” between 4 and 6 as “moderate quality,” and below 4 as “poor quality.” In the present study, articles with good and moderate quality were considered acceptable and, given their importance and quality, were reviewed and analyzed for meta-analysis. (Saaiq M and Ashraf B., 2024)

Data extraction

From all articles that received the necessary critical score, the following information was extracted: (1) study characteristics (author’s name, publication year, study location, study type); (2) sample characteristics (sample size, age range, gender distribution, years of experience, and specialty area); (3) tools used to assess dentists’ awareness; (4) results of dentists’ awareness in the areas of diagnosis, prevalence, and etiology. The mentioned studies were entered into the Evidence Table (Table 1).

Table 1.

Evidence table of main characteristics of studies included in the systematic review

Statistical analysis

For statistical analysis, data were entered into a pre-designed table in Excel and analyzed using Stata 18 software (Stata Corp, College Station, TX, USA) with a 95% confidence interval (CI). Since the results of different studies did not have equal value, inverse variance was used to weight the studies. Heterogeneity of studies was assessed by Cochran’s Q chi-squared statistical test, and its quantitative value was expressed by the I² statistic. To calculate the mean overall effect size, a fixed-effects model was initially used, and if significant heterogeneity was present, a random-effects model was employed. Publication bias was evaluated by visual inspection of funnel plots. Statistical assessment of funnel plot asymmetry was performed using Egger regression and Begg’s adjusted rank correlation tests to identify the possibility of articles with a higher chance of publication and reduce the effect of publication bias.

Result

The search results from predetermined databases, encompassing 2064 articles up to March 2026, are related to dentists’ awareness of MIH. Specifically, 785 articles were retrieved from PubMed, 1117 from Web of Science, 160 from Scopus, and 2 from Google Scholar. After removing 274 duplicate articles, 1790 remained for title and abstract review.

1694 articles were excluded based on their titles, 64 based on their abstracts, and 5 based on their full texts. Finally, after reviewing the inclusion and exclusion criteria and full-text articles, 24 studies were selected for validation and quality assessment. The search strategy, detailing included items and reasons for article exclusion, is reported in the PRISMA flow chart (Fig. 1).

Fig. 1.

PRISMA Flowchart

Twenty cross-sectional studies that met the required score based on the JBI checklist were included, and 18 studies were used for quantitative evaluations and meta-analysis.

Study characteristics

Cross-sectional studies concerning dentists’ awareness of MIH exist globally across several countries, (Sajadi et al. 2021; Karkoutly et al. 2022; Hamza et al. 2021, 2023; Serna-Muñoz et al. 2020; Alanzi et al. 2018; Silva and Manton 2016; Skaare et al. 2021; Elshiekh 2023; Yehia et al. 2021; Liu and He 2022; Gamboa et al. 2018; Papanikolaou et al. 2025; Gambetta-Tessini et al. 2016; Gómez-Clavel et al. 2023; Gunay 2023; Dian et al. 2022; Delgado et al. 2022; Elhennawy et al. 2021). The most recent article, published in the Netherlands, collected results via a questionnaire distributed randomly among GDs, PDs, and other specialists at a specific institution (Papanikolaou et al. 2025). The oldest article dates back to 2014 from Malaysia, with the sample size of 131 participants consisted of female dentists under 30 years old with less than 5 years of work experience. This study examined the awareness of two groups, GDs and PDs, who attended an international conference in that country (Hussein et al. 2014). The sample size of the selected studies varied from 100 dentists in a Norwegian study to 1142 participants in a Syrian study (Skaare et al. 2021; Karkoutly et al. 2022). Although some articles did not specify the demographic information of participants such as gender, age, and years of experience, most studies included a larger number of female dentists. Notably, in the Norwegian study, 91% of the dentists were female (Skaare et al. 2021). The target population for assessing awareness of MIH differed across studies, allowing for comparative analysis. In studies from Egypt (Elshiekh 2023), China (Liu and He 2022), Switzerland (Hamza et al. 2021), Turkey (Gunay 2023), and Germany (Elhennawy et al. 2021), the research focused solely on final-year dental students, potentially providing valuable insights into the awareness of young dentists regarding MIH, a relatively new developmental condition introduced in 2006. Other articles compared the awareness of GDs, PDs, and other specialists. In most studies, the GDs population participating was larger than the other two groups; for instance, in a study from Hong Kong, China, 89.4% of participants were GDs and only 10.6% were pediatric specialists (Gamboa et al. 2018). The awareness assessment tool in published cross-sectional studies involved a questionnaire distributed electronically or on paper among participants. Only the study conducted in Switzerland translated the questionnaire into English and German to facilitate understanding (Hamza et al. 2021). Mean, maximum, and minimum awareness scores were reported only in the questionnaires of studies from Egypt (Yehia et al. 2021), Indonesia (Dian et al. 2022), and Portugal (Delgado et al. 2022), with other questionnaires varying to some extent. However, most questionnaires were categorized into three domains: dentists’ awareness, attitude, and clinical experience. The greatest overlap among questionnaire questions was observed in the domain measuring dentists’ awareness, which was the focus of the current study.

Of the 20 studies included in this review, 18 (Elshiekh, 2023; Hamza et al., 2023; Liu and He 2022; Dain et al., 2022; Delgado et al. 2022; Skaare et al., 2012; karkoutly et al., 2022; Hamza et al.,2021; yehia et al., 2021; Sajadi et al.,2021; Elhennawy et al.,2021; Alanzi et al. 2018; Serna-Muñoz et al. 2020; Gambo et al.,2018; Gambetta-Tessini et al.,2016; Hussein et al.,2014; Silva et al., 2016; Papanikolaou et al., 2025; Gómez-Clavel et al., 2023) were quantitatively synthesized using meta-. A summary of the characteristics of the selected articles is presented in Table 1.

Risk of bias assessment

The quality of the included cross-sectional studies was assessed using the JBI check list. All of the studies had low overall risk of bias; except for one study (Kalkani et al. 2016) which had moderate overall risk of bias. (Fig. 2)

Fig. 2.

Methodological quality assessment based on the Joanna Briggs Institute critical appraisal checklist for studies reporting prevalence data. Questions, Q1 = Was the sample frame appropriate to address the target population?; Q2 = Were study participants recruited in an appropriate way?; Q3 = Was the sample size adequate?; Q4 = Were the study subjects and setting described in detail?; Q5 = Was data analysis conducted with sufficient coverage of the identified sample?; Q6 = Were valid methods used for the identification of the condition?; Q7 = Was the condition measured in a standard, reliable way for all participants?; Q8 = Was there appropriate statistical analysis?; Q9 = Was the response rate adequate, and if not, was the low response rate managed appropriately?

Data synthesis and meta-analysis

The articles’ questionnaires included a set of questions designed as yes/no or multiple-choice items across the three domains: awareness, attitude, and clinical experience. The questionnaire related to dentists’ awareness covered a wide range of questions and statements concerning dentists’ awareness of MIH. A large portion of the results could not be included in the meta-analysis due to the heterogeneity of the questionnaires. Therefore, only dentists’ awareness in the areas of diagnosis, prevalence, and etiology of MIH, which were similar across studies, was analyzed. The ability of dentists to diagnose MIH was assessed through responses to the following common questionnaire questions: presentation of clinical images of hypo-mineralization for diagnosis, questions about the most common clinical manifestation of MIH, the most commonly affected teeth in the permanent and primary dentition, and questions about other developmental conditions that mimic MIH manifestations. The most common differential diagnoses mistakenly identified as MIH by dentists were enamel hypoplasia and fluorosis. The reported statistical results related to these questions indicate dentists’ awareness in diagnosing and differentiating MIH from other enamel developmental anomalies.

Awareness questions regarding the prevalence of MIH in the target country were examined through frequency estimations in ranges of < 5%, 5–10%, 10–20%, and > 20%, as well as the frequency of clinical encounters with MIH. The reported statistical results for these questions indicate the percentage of dentists who had an accurate estimation of MIH prevalence, demonstrating dentists’ awareness of MIH prevalence.

Meta-analysis results

Assessment of dentists’ awareness regarding the differentiation of MIH from other developmental defects

The pooled results from the aforementioned studies indicated awareness in differentiating MIH from other similar developmental defects, with a 95% confidence interval (CI), as follows: GDs showed 41% (95% CI: 0.31to 0.50; p-value = 0.001), PDs showed 94% (95% CI: 0.89 to 0.99; p-value = 0.001), and ADPs showed 79% (95% CI: 0.71 to 0.86; p-value = 0.001). (Fig. 3)

Fig. 3.

Meta- analysis of proportion of knowledge on prevalence, differential diagnose and etiologic factors of molar incisor-hypo-mineralization in general dentists (GDs), Pediatric dentists (PDs) and all dental practitioners (ADPs)

Furthermore, heterogeneity was observed among the studies based on the H² index of 28.51 and I² of 96.49% in the GDs’ group, H² of 36.5 and I² of 81.34% in the PDs’ group, and H² of 92.85 and I² of 98.92% in the group of ADPs. Therefore, the effect size estimation was calculated using the Random-effects model.

Assessment of dentists’ awareness regarding the prevalence of MIH in the target country

The combined findings from the mentioned studies showed the following levels of awareness regarding the prevalence of MIH with a 95% CI: GDs showed 26% (95% CI: 0.16 to 0.35; p-value = 0.001), PDs showed 94% (95%CI: 0.89 to 0.98; p-value = 0.001), and ADPs showed 23% (95% CI: 0.17 to 0.30; p-value = 0.001). (Fig. 3)

Additionally, heterogeneity was observed among the studies based on the H² index of 31.77 and I² of 96.85% in the GDs’ group, H² of 4.38 and I² of 77.19% in the PDs’ group, and H² of 51.44 and I² of 98.06% in the group of ADPs. Therefore, the effect size estimation was calculated using the Random-effects model.

Assessment of dentists’ awareness regarding “genetics” as a contributing factor in the etiology of MIH

The overall results of the studies reveal awareness regarding the etiological factor of genetics in the development of MIH lesions as described below with a 95% CI as follows: GDs showed 78% (95% CI: 0.73 to 0.84; p-value = 0.001), PDs showed 22% (95% CI: 0.12 to 0.31; p-value = 0.001), and ADPs showed 59% (95% CI: 0.49 to 0.69, p-value = 0.001). (Fig. 3)

Furthermore, heterogeneity was observed among the studies based on the H² index of 7.65 and I² of 86.92% in the GDs’ studies, H² of 7.11 and I² of 85.93% in the PDs’ studies, and H² of 94.76 and I² of 98.94% in the studies of ADPs. Therefore, the effect size estimation was calculated using the Random-effects model.

Assessment of dentists’ awareness regarding “chronic diseases” as a contributing factor in the etiology of MIH

The synthesis of the findings from the aforementioned studies revealed awareness regarding the etiological factor of chronic diseases in the development of MIH lesions with a 95% CI as follows: GDs showed 21% (95% CI: 0.16 to 0.26; p-value = 0.001), PDs showed 53% (95% CI: 0.38 to 0.68; p-value = 0.001), and ADPs showed 59% (95% CI: 0.47 to 0.71; p-value = 0.001). (Fig. 3)

Additionally, heterogeneity was observed among the studies based on the H² index of 7.54 and I² of 86.74% in the GDs’ studies, H² of 22.94 and I² of 95.64% in the PDs’ studies, and H² of 170.48 and I² of 99.41% in the studies of ADPs. Therefore, the effect size estimation was calculated using the Random-effects model.

Assessment of dentists’ awareness regarding “acute diseases” as a contributing factor in the etiology of MIH

The combined findings from the previously mentioned studies indicated awareness of the role of acute disease causes in the development of MIH lesions, with a 95% confidence interval reported as follows: GDs showed 63% (95% CI: 0.54 to 0.73; p-value = 0.001), PDs showed 66% (95% CI) 0.47 to 0.85; p-value = 0.001), and ADPs showed 52% (95% CI: 0.43 to 0.62; p-value = 0.001).

Furthermore, heterogeneity was observed among the studies based on the H² index of 28.21 and I² of 96.46% in the GDs’ studies, H² of 53.13 and I² of 98.12% in the PDs’ studies, and H² of 88.88 and I² of 98.87% in the studies of ADPs. Therefore, the effect size estimation was calculated using the Random-effects model.

Assessment of dentists’ awareness regarding “antibiotic use” as a contributing factor in the etiology of MIH

The aggregated findings from the previously cited studies suggest awareness of antibiotic use as an etiological factor in the development of MIH lesions, with a 95% confidence interval reported as follows: GDs showed 61% (95% CI: 0.47 to 0.75; p-value = 0.001), PDs showed 67% (95% CI: 0.50 to 0.84; p-value = 0.001), and ADPs showed 51% (95% CI: 0.42 to 0.61; p-value = 0.001). (Fig. 3)

Additionally, heterogeneity was observed among the studies based on the H² index of 81.49 and I² of 98.77% in the GDs’ studies, H² of 42.09 and I² of 97.62% in the PDs’ studies, and H² of 78.80 and I² of 98.73% in the studies of ADPs. Therefore, the effect size estimation was calculated using the Random-effects model.

Assessment of dentists’ awareness regarding “environmental pollutions” as a contributing factor in the etiology of MIH

The combined evidence from the previously referenced studies reflects awareness of environmental pollution as a contributing etiological factor in the development of MIH lesions, with a 95% confidence interval presented as follows: GDs showed 59% (95% CI: 0.45 to 0.73; p-value = 0.001), PDs showed 46% (95% CI: 0.30 to 0.62; p-value = 0.001), and ADPs showed 37% (95% CI: 0.28 to 0.45; p-value = 0.001). (Fig. 3)

Furthermore, heterogeneity was observed among the studies based on the H² index of 96.82 and I² of 98.97% in the GDs’ studies, H² of 26.27 and I² of 96.19% in the PDs’ studies, and H² of 90.70 and I² of 98.90% in the studies of ADPs. Therefore, the effect size estimation was calculated using the Random-effects model.

Assessment of dentists’ awareness regarding “fluoride exposure” as a contributing factor in the etiology of MIH

The synthesized findings from the previously mentioned studies demonstrate awareness of excessive fluoride exposure as an etiological factor in the development of MIH lesions, with a 95% confidence interval reported as follows: GDs showed 45% (95% CI: 0.37 to 0.54; p-value = 0.001), PDs showed 46% (95% CI: 0.30 to 0.62; p-value = 0.001), and ADPs showed 15% (95% CI: 0.10 to 0.21; p-value = 0.001). (Fig. 3)

Additionally, heterogeneity was observed among the studies based on the H² index of 23.49 and I² of 95.74% in the GDs’ studies, H² of 26.27 and I² of 96.19% in the PDs’ studies, and H² of 67.38 and I² of 98.52% in the studies of ADPs. Therefore, the effect size estimation was calculated using the Random-effects model.

Accumulation of the result

In the ADPs group, genetics and chronic diseases were equally recognized (59%), followed by acute diseases (52%) and antibiotic use (51%). Overall, environmental pollution, antibiotic use, and acute diseases showed similar and closely clustered results across the three target groups. Environmental pollution was recognized as an MIH etiology by 51% of GDs, 46% of PDs, and 37% of ADPs. Drug therapy, primarily the use of antibiotics that disrupt the amelogenesis process by affecting ameloblasts early in life, was considered responsible by 61% of GDs, 67% of PDs, and 51% of ADPs. Acute childhood diseases, particularly febrile types that compromise enamel structure and formation, were believed to contribute to MIH development by 63% of GDs, 66% of PDs, and 52% of ADPs. Fluoride exposure, with a result of 15%, recorded the lowest frequency among the etiological factors from the perspective of the ADPs. Furthermore, in a case-by-case examination of etiological factors, the highest statistical frequency was observed in GDs for genetic etiology and environmental pollution, while PDs showed the highest frequency for chronic disease, acute disease, antibiotic/drug therapy, and fluoride exposure (with a minimal difference).

Discussion

The present meta-analysis was conducted with the primary aim of investigating dentists’ awareness of MIH, focusing specifically on knowledge gaps concerning its diagnosis, etiology, and prevalence. To facilitate a more precise comparison of results, the target population was stratified into three distinct subgroups: GDs, PDs, and ADPs, which included various dental specialists. Although efforts were made to select studies employing similar questionnaires, variations in demographic data—such as clinical experience, practice location (urban vs. suburban), and differing age and gender ratios across the included articles—contributed to high heterogeneity in the meta-analysis results. This heterogeneity was subsequently addressed through the implementation of a random-effects model.

The meta-analysis results concerning dentists’ ability to differentiate MIH from other developmental defects exhibited a marked variation across the three defined subgroups. As anticipated, the awareness level of PDs was significantly higher than that of both GDs and ADPs. This finding is somewhat predictable, given that the clinical signs of MIH typically manifest in the first decade of life, leading children with this condition to be commonly referred to pediatric specialists. This patient demographic ensures that PDs have a substantially higher encounter rate with MIH and greater clinical experience in its management (Hamza et al. 2023). A comparison between the results for GDs and ADPs indicated that the ADPs group displayed higher awareness than GDs but still fell below the proficiency of PDs. The lowest overall awareness score regarding the diagnosis and differentiation of MIH from other enamel defects was reported in the 2020 study by Serna-Munoz et al. (Serna-Muñoz et al. 2020), which surveyed GDs in Spain, nearly a third of whom possessed over 15 years of experience and worked in private practice. According to the included studies, the lesions most frequently leading to diagnostic uncertainty for MIH were, in descending order, Amelogenesis Imperfecta, enamel hypoplasia, and fluorosis (Elhennawy et al. 2021; Hamza et al. 2021).

While precise global reporting of MIH prevalence by country and year remains challenging, dentists’ awareness of its frequency can be compared by examining their estimated ranges. (Navarro and Buldur, 2024). Considering the global average prevalence of MIH (13.1–14.2%), many questionnaire-based studies have assessed dentists’ awareness by asking them to estimate national prevalence using predefined ranges (e.g., 5–10%, 10–20%), with reported responses varying considerably across population. (Alanzi et al. 2018; Skaare et al., 2012) The meta-analysis results demonstrated that dentists’ awareness of national MIH prevalence was significantly poor in both the GDs group and the ADPs group. The importance of accurately assessing the prevalence awareness of this developmental defect is heightened in borderline cases, as predicting the frequency and clinical encounter rate of MIH is a critical component for establishing a correct diagnosis and formulating an appropriate treatment plan (Yehia et al. 2021).

Dentists’ awareness of the etiological factors of MIH was investigated separately across the three target groups. The results revealed a notable discrepancy: PDs, unlike GDs and ADPs, did not identify genetics as the primary factor, with only 22% recognizing specific genotypes involved in MIH development. In the view of PDs, the use of certain antibiotics, and acute and chronic diseases affecting the mother and fetus (especially during the last trimester of pregnancy and during infancy) were considered more important factors, respectively. (Gamboa et al. 2018) PDs equally considered environmental pollution and high fluoride concentrations (46% for both) as causative agents for MIH. In contrast, among GDs, genetics (78%), acute diseases, and antibiotic use were the most commonly recognized etiological factors, with chronic diseases considered less important compared to the other two groups.

The closest agreement between etiological factors reported by GDs and PDs was related to fluoride exposure (45% vs. 46%), suggesting a shared understanding of fluoride’s role in the etiology among both groups. In contrast, the greatest disagreement was observed concerning the role of genetics (78% vs. 22%). This marked difference may indicate that GDs tend to overestimate the impact of genetic factors on the condition. Previous studies have highlighted similar discrepancies between general and specialist practitioners. (Gamboa et al. 2018; Dian et al. 2022; Gómez-Clavel et al. 2023)General dentists often attribute a higher etiological role to genetic predispositions, possibly due to less exposure to recent research emphasizing multifactorial and environmental contributions (1). In contrast, pediatric dentists, likely due to continuous education and specialty training, are more aligned with the current literature. These findings highlight the need for further educational efforts to harmonize perceptions among dental professionals regarding the etiology of such conditions.

Across the three professional groups, genetics, chronic illnesses, acute childhood diseases, environmental pollution, and antibiotic therapy were consistently regarded as relevant etiological factors for MIH, with only modest variations in emphasis among the groups. In general, GDs tended to attribute a stronger role to genetic factors and environmental pollution, whereas PDs more frequently highlighted chronic and acute systemic conditions as well as medication-related influences, including antibiotic use. ADPs showed broadly similar patterns but with slightly lower recognition of fluoride exposure compared with the other groups. Overall, the etiological perceptions among the three groups demonstrated comparable trends, differing mainly in the degree of emphasis placed on specific biological or environmental contributors.

The results of this study support the long-standing hypothesis of an interaction between genetic predisposition and environmental factors in the development of MIH. The existing differences in professional opinion underscore the fact that, to date, no single etiological factor has been definitively identified as the primary or singular cause of MIH, thereby necessitating further in-depth studies in this area. Identifying distinct MIH genotypes is inherently complicated due to their susceptibility to environmental factors, which themselves can manifest differently depending on whether they affect the mother or the fetus pre-, peri-, or postnatally. For this analysis, we utilized the most common environmental etiological factors included in the study questionnaires, which allowed dentists to select multiple options. (Weerheijm 2004)

Given the significant impact of MIH on patient quality of life and the complexity of its management, the observed knowledge gaps among dental practitioners—particularly GDs—highlight a crucial need for targeted professional development. The disparities found in this meta-analysis regarding the diagnosis, prevalence, and etiology of MIH strongly suggest that current undergraduate and continuing education programs may be insufficient in adequately preparing all dentists for its comprehensive management. To address this, it is imperative to establish mandatory, structured, and contemporary continuing professional development courses focused specifically on MIH. These programs should emphasize the latest consensus on diagnostic criteria, differential diagnosis from similar enamel defects, evidence-based management protocols (including remineralization strategies and restorative approaches), and the current understanding of genetic and environmental etiological factors. By standardizing and elevating the educational level across all dental subgroups, we can ensure earlier and more accurate diagnosis, leading to timely intervention and ultimately improving the long-term oral health outcomes for children affected by MIH. (Silva et al. 2016)

While this meta-analysis provides a rigorous overview of MIH awareness using a comprehensive systematic methodology, the following limitations must be considered when interpreting our findings:

• Heterogeneity and Methodological Variability: A significant challenge was the inherent heterogeneity across studies, likely stemming from disparate questionnaire designs, varying definitions of MIH awareness, and differences in demographic characteristics. While we utilized a random-effects model and performed subgroup analyses to account for this, the lack of a standardized assessment tool across the field inevitably limits the precision of our pooled estimates.

• Self-reporting Bias: As with many survey-based studies, our reliance on self-reported data introduces the possibility of social desirability bias, where practitioners might overestimate their knowledge level. This may have led to an inflation of the reported awareness levels.

• Search Strategy Constraints: Although we employed a robust search strategy, the limitation to three major databases and the exclusion of regional databases like Embase or LILACS may have introduced a degree of publication or language bias, potentially overlooking niche or regionally specific evidence. Furthermore, the exclusion of one study due to full-text unavailability remains a minor limitation regarding the completeness of the data.

• Implications for Future Research: The aforementioned limitations underscore a critical need for the development and adoption of standardized, validated instruments in MIH research. Future studies should prioritize longitudinal designs and uniform sampling procedures to enhance cross-study comparability and provide a more robust evidence base for educational initiatives.

Conclusion

Awareness of dental practitioners regarding the diagnosis, prevalence, and etiology of MIH appears to differ among GDs, PDs, and ADPs across the included countries. The results indicate a potential need for further education and training to support early diagnosis and management of MIH.

Author contributions

Study concept and design: N.A Acquisition of data: N.Z, M.TAnalysis and interpretation of data: N. A, N.Z, M. TDrafting of the manuscript: N.A, N.Z, M.T. Critical revision of the manuscript for important intellectual content: N.A. Statistical analysis: M. T.Study supervision: N. A.

Funding

This research project don’t have any funding source.

Data availability

The data that support the findings of this study are available on request from the corresponding author.

Declarations

Ethical statement

The study was approved by the Ethics Committee of Isfahan University of Medical Sciences (IR.MUI.DHMT.REC.1403.132).also the study protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) with ID of CRD420251119530.

Consent for publication

This manuscript does not contain any individual person’s data in any form (including individual details, images or videos).

Consent to participate

This manuscript does not contain any individual person’s data in any form (including individual details, images or videos).

Competing interests

The authors declare no competing interests.