A study in the October 2026 issue of Clinical and Experimental Dental Research (published online September 8) compared health records for about 4.7 million BigMouth patients and 254,700 NIH All of Us participants. The authors found statistically significant sex differences for 70% of the dental and oral conditions they could test in All of Us, and for 39% in BigMouth. In BigMouth, almost every difference leaned toward women.
Sex is a recognized biological variable in medicine, but the authors point out that population-based studies of sex differences in dental, oral and craniofacial disease are limited. As of October 2026, this U.S. health-record analysis helps fill that gap. The authors describe its sample as larger than previous studies of the question.
The paper, "Examining Electronic Health Records to Investigate Sex Differences in Oral Diseases and Conditions," appears in volume 12, issue 5 of Clinical and Experimental Dental Research (DOI 10.1002/cre2.70455). The authors are E. Fetchko and A. Letra of the University of Pittsburgh School of Dental Medicine and L. Sangalli of Midwestern University's College of Dental Medicine. The journal received the manuscript on April 29, 2026, accepted it on August 27, 2026 and published it online on September 8, 2026, in the October issue. The article is open access.
How the Study Was Designed
The team ran a retrospective cross-sectional study of adults over 18 in two U.S. data repositories:
- NIH All of Us Research Program (n = 254,700). The paper describes it as holding "medical and dental record data from individuals across the US who agree to share their data."
- BigMouth Dental Data Repository (n ≈ 4.7 million). According to the authors, its data "is directly imported from dental electronic health records from eleven participating dental schools."
For each diagnosis concept, the researchers counted how many females and males had it in each database. They tested for sex differences with chi-square tests at a strict significance threshold (α ≤ 0.0002) and reported female-to-male odds ratios (ORs). An OR above 1 means the condition was recorded more often in women. An OR below 1 means it was recorded more often in men.
What the All of Us Data Showed
The researchers found 216 dental, oral and craniofacial concepts in All of Us. Of these, 87 had sex-stratified data. Significant differences turned up for 61 of the 87 (70%): 33 leaned female (54%) and 28 leaned male (46%).
Recorded more often in women:
- Oral soft-tissue conditions: recurrent aphthous stomatitis (OR 5.37) and xerostomia (OR 4.96).
- Tooth development and eruption: anodontia (OR 5.29).
- Pulpal and periapical conditions: dental abscess (OR 2.78), reversible pulpitis (OR 2.68) and toothache (OR 2.56).
- Periodontal diagnoses: aggressive periodontitis (OR 2.56) and chronic periodontitis (OR 1.33).
- Dental caries as a general concept. The paper reports ratios between about 1.3 and 1.64 in different sections.
On the male side, oral cancer stood out. In the paper's Table 1, malignant tumour of the oral cavity leaned male (OR 0.50), and malignant tumour of the tongue leaned male more strongly (OR 0.18). In other words, these diagnoses were recorded more often in men.
What the BigMouth Data Showed
The authors used BigMouth to check what they found in All of Us. Of 243 concepts identified there, 230 had sex-specific data. Significant differences appeared for 90 of them (39%). The split was lopsided: 87 (97%) leaned female and only 3 (3%) leaned male.
Notable female-leaning ratios in BigMouth included:
- Temporomandibular disorders: OR 9.72, among the highest ratios in this dataset.
- Xerostomia: OR 5.93.
- Cementum defect: OR 5.39.
- Sensitive dentin: OR 3.40.
- Symptomatic apical periodontitis: OR 2.77.
Only a few conditions leaned male in BigMouth. They included root caries (female-to-male OR 0.80) and malignant neoplasm (OR 0.52). The authors also note a possible "inherent bias in BigMouth as the participants included mostly females," which matters when you read its 97% female-leaning figure.
Where the Two Databases Agreed — and Where They Did Not
Only 20 concepts matched exactly between the two repositories. Some of those pointed the same way in both. Dental abscess and reversible pulpitis, for example, leaned female in each database. But 8 of the 20 showed sex bias in opposite directions. These included generalized moderate periodontitis, localized chronic periodontitis, chronic apical abscess, pulp degeneration/necrosis, and attrition and abrasion of teeth.
That disagreement matters. The authors say plainly that "inherent differences among the databases" may "contribute to occasional discrepant findings." All of Us draws on people across the U.S. who volunteer their records. BigMouth draws on patients treated at 11 dental schools. Even so, the authors count the large sample sizes and the wide range of conditions studied among the paper's strengths.
Pro Tip: Read the ORs as differences in how often a diagnosis appears in health records, not as individual risk. Who seeks care, who gets referred, and how a diagnosis gets coded all shape what a record shows. Treat the ratios as a prompt for questions, not as screening rules.
Why Do Canadian Dentists Need to Pay Attention to a U.S. Dataset?
This study used no Canadian data, and the authors call for "additional studies in other populations." Practices in Toronto, Mississauga, Markham or anywhere else in Ontario should not assume these numbers transfer directly to their own patients. Still, the paper raises three practical points for Canadian clinicians.
1. Sex is a variable worth recording carefully
The whole analysis depended on records that captured both a diagnosis and the patient's sex. If your practice management software stores diagnoses as free-text notes rather than structured codes, your own data can't answer questions like these. Structured diagnostic coding helps your practice audit itself. It also lets your data feed research if you ever join a study.
2. Some female-leaning conditions are easy to overlook
Xerostomia, temporomandibular disorders and dentin sensitivity all showed strong female-leaning ratios in at least one database. These symptoms can go unmentioned unless a clinician asks. The study doesn't tell clinicians to screen differently by sex. It does support asking every patient directly about dry mouth, jaw pain and sensitivity, and documenting the answers.
3. Oral cancer vigilance in men remains relevant
Oral cancer concepts leaned male in both databases (All of Us oral cavity OR 0.50 and tongue OR 0.18; BigMouth malignant neoplasm OR 0.52). That does not replace any screening guidance. It does support continued attention to soft-tissue examination for every adult patient.
Pro Tip: If your team reviews charting quality at a monthly meeting, pick one category from this study, such as xerostomia or TMD, and spend 15 minutes checking whether your intake form and recall exam prompt for it consistently.
How This Fits With Earlier Research
The authors note that earlier studies of sex differences in dental disease have been mixed. In the paper's words, research on apical periodontitis "yielded mixed outcomes," and studies of dental caries "have conflicting findings." They attribute these discrepancies to differences in sample sizes, the parameters measured and the populations studied. Their own contribution is scale: more than 200 concepts compared across 4,501,648 females and males in the U.S.
The paper's conclusion is careful. It reports "evidence of sex bias in numerous oral and dental conditions in the populations studied" and calls for further work. It does not propose clinical guidelines, though the authors say the findings could eventually support "clinical translation with sex-specific strategies" to improve oral health.
What Comes Next
The obvious next step is replication outside the U.S. Researchers would also need to adjust for the factors that shape who appears in a health record in the first place, such as insurance coverage and the reasons people visit a dental school clinic. For Canadian dental professionals, the takeaway for now is modest: record diagnoses in a structured way, ask every patient about symptoms that can go unmentioned, and read sex-difference headlines with the same scrutiny as any other observational finding.
EBIKO Dental will continue monitoring dental research that affects how Canadian practices diagnose and document care. Visit ebiko.ca for more updates for dental professionals across the GTA and Canada.
Sources
- Fetchko E, Sangalli L, Letra A. Examining Electronic Health Records to Investigate Sex Differences in Oral Diseases and Conditions. Clinical and Experimental Dental Research. 2026;12(5). doi:10.1002/cre2.70455
- Europe PMC record (PMID 42709938): europepmc.org/article/MED/42709938
Frequently Asked Questions
Q: Are dental diseases more common in women or men?
It depends on the condition. In this U.S. study, published in the October 2026 issue, xerostomia, temporomandibular disorders and several pulpal diagnoses appeared more often in women's records. Oral cavity cancer concepts and root caries appeared more often in men's. Results also differed between the two databases studied.
Q: How big was the sex-differences study in Clinical and Experimental Dental Research?
It analyzed records from 254,700 adults in the NIH All of Us Research Program and about 4.7 million patients in the BigMouth Dental Data Repository, which collects data from 11 U.S. dental schools.
Q: Does this study change how Canadian dentists should screen patients?
No. The study used only U.S. data, and the authors call for studies in other populations. It is still a useful reminder to ask every patient about symptoms that may go unmentioned, such as dry mouth and jaw pain, and to record diagnoses consistently.