Large Peruvian study adds data on impacted and extra teeth
Bottom line
A new cross-sectional study in the Journal of Clinical and Experimental Dentistry examined 7,903 panoramic radiographs from two radiology centers in Peru to estimate how often impacted teeth and supernumerary teeth appear in young people ages 13 to 20. The study adds a large, recent dataset from 2020 to 2025 to a body of literature showing that these developmental dental anomalies are uncommon overall, but clinically important because they can alter eruption, crowding, and occlusion. Earlier Latin American radiographic research, including a 2,000-image study spanning Peru, Colombia, and Bolivia, similarly found relatively low prevalence, with impacted teeth and mesiodens among the more frequent findings. (researchgate.net)
Why it matters: While the paper is in human dentistry, the take-home point for veterinary teams is familiar: missing or delayed-erupting teeth shouldn't be assumed absent without imaging. Veterinary references and clinical guidance consistently note that radiography is needed to distinguish congenitally missing teeth from retained, impacted, or supernumerary teeth, and that extra or unerupted teeth can contribute to crowding, malocclusion, plaque retention, periodontal disease, or more serious pathology. In dogs, unerupted teeth are often found incidentally on routine dental radiographs, and some breeds appear at especially high risk for associated lesions such as dentigerous cysts. (academy.royalcanin.com)
What to watch: Watch for whether the Peruvian authors' full results spur more comparative work on age, sex, tooth location, and imaging-based screening strategies that could also inform earlier detection conversations in veterinary dentistry. (researchgate.net)
A large new Peruvian radiographic study is putting fresh numbers on two common developmental dental problems: impacted teeth and supernumerary teeth. According to the study summary, investigators reviewed 7,903 digital panoramic radiographs from two radiology centers in Peru, focusing on patients ages 13 to 20 whose images were taken between 2020 and 2025. That makes it a notably large dataset for a topic that usually appears in smaller, single-center prevalence reports. (researchgate.net)
The study builds on earlier work from Latin America rather than arriving in a vacuum. A 2020 cross-sectional study using 2,000 panoramic radiographs from Peru, Colombia, and Bolivia found low overall prevalence for both impacted teeth and supernumerary teeth, with the upper left canine the most frequently impacted tooth and mesiodens the most common supernumerary finding. Peru also showed the highest prevalence of mesiodens in that earlier multinational sample. (pubmed.ncbi.nlm.nih.gov)
That broader literature matters because prevalence estimates vary a lot depending on age, population, and what exactly gets counted. A recent meta-analysis on impacted third molars reported a pooled prevalence of 36.9% per subject, underscoring how heavily prevalence can shift when third molars dominate the case definition. Separate literature on supernumerary teeth based on panoramic radiographs has estimated prevalence in the roughly 1.2% to 3% range, while also warning that panoramic imaging may underdetect some cases. In other words, large imaging studies are useful, but methodology shapes the headline number. (pubmed.ncbi.nlm.nih.gov)
For veterinary professionals, the most relevant parallel is not the exact human prevalence figure but the clinical lesson around imaging and follow-up. Veterinary guidance from Royal Canin Academy says absent teeth should be evaluated radiographically to rule out retained or impacted teeth, and notes that supernumerary teeth can cause eruption problems, crowding, deviation of adjacent teeth, and plaque accumulation that predisposes to periodontal disease. Merck Veterinary Manual likewise notes that hyperdontia in dogs most often affects the maxilla and can lead to crowding, malocclusion, discomfort, and dental disease. (academy.royalcanin.com)
Published veterinary case series reinforce that this is not just a cosmetic issue. In a Frontiers in Veterinary Science review of 73 cases of unerupted teeth in dogs and cats, most cases were found incidentally during routine intraoral radiography rather than because of obvious clinical signs. Among dogs in that series, first premolars were the most commonly unerupted teeth, and the authors highlighted associated pathology including dentigerous cysts, with especially notable risk in boxers seen at the participating clinics. (frontiersin.org)
There doesn't appear to be a press release or broad industry reaction tied to the Peruvian paper yet, and I did not find outside expert commentary specifically addressing this new study. Still, the surrounding literature is consistent: early radiographic identification can change management. Human studies have linked impacted supernumerary teeth to delayed eruption, displacement, and spacing problems, and a systematic review found that many impacted maxillary incisors erupt spontaneously after surgical removal of the obstructing supernumerary tooth. That supports a broader principle veterinarians already know well: identifying the anatomic cause early can preserve options. (pubmed.ncbi.nlm.nih.gov)
Why it matters: For general practitioners and veterinary dentists, this is a reminder that developmental tooth anomalies are easy to miss without imaging, especially in young patients with apparently “missing” teeth or crowding. The human study adds epidemiologic weight to a problem that crosses species lines: extra teeth and unerupted teeth may be uncommon, but when present they can reshape eruption patterns, complicate occlusion, and create downstream pathology. For pet parents, that can mean a seemingly minor finding at a juvenile exam turns into a radiographic workup, referral, extraction, or long-term monitoring plan. (researchgate.net)
What to watch: The next thing to watch is whether the full paper's detailed results, including tooth-specific distribution and any age- or sex-linked patterns, are picked up in follow-on studies or comparative reviews, and whether veterinary dentistry continues moving toward more routine imaging-based screening for young animals with missing, crowded, or delayed-erupting teeth. (researchgate.net)