An interesting article explored the prevalence of caries experience and periodontal pathology on asymptomatic wisdom teeth in young adults appears in a 2012 issue of the Journal of Oral and Maxillofacial Surgery by Rachel N. Garaas and et al. titled “Prevalence of third molars with caries or periodontal pathology in young adults” (J Oral Maxillofac Surg. vol. 70, pages 507-513, 2012). The article seeks to help inform young adults who are seeking advice about the extraction or retention of wisdom teeth about if these teeth can remain symptom free or not.
The study includes 409 patients with an average age of 25. The authors define a periodontal probing depth of at least 4 mm as indicative of periodontal inflammatory disease. The authors found that a periodontal probing depth of at least 4 mm was detected more often on a mandibular wisdom tooth than a maxillary wisdom tooth (64% versus 20%). The authors found that fewer subjects were affected by wisdom teeth caries experience when compared to first and second molar caries experience (24% versus 73%). Caries experience was detected on a third molar exclusively in only 3 subjects (<1%).
The authors further found that 229 of the patients had wisdom teeth at the occlusal plane (often used as a cutoff for it is erupted or not). In this case 26% of the patients had both wisdom teeth caries experience and at least 1 periodontal probing depth of 4 mm or more. Only 16% of the patients were free of both wisdom teeth experience and periodontal inflammatory disease.
I have included this study on the risks of keeping wisdom teeth page. Other results of the study are found but you will have to read the article for all the details. Naturally, in the discussion the authors compare their results to some other studies. In their discussion they include comparisons with the Piedmont 65+ study and the Atherosclerosis Risk in Communities (ARIC) study. (I also discuss these studies on the risks of keeping wisdom teeth page). They present a useful chart (Table 2) in the article to highlight the differences and similarities of their study and the 2 comparison studies.
For example, in their study 24% of the patients had caries experience of a wisdom tooth, which was similar to the caries experience of patients in the Piedmont 65+ study (28%); however, this is different than the caries experience of patients reported in the ARIC study (77%).
Futher, in their study 65% of the patients were reported to have peridontal pathology which was similar to the Piedmont 65+ study (68%) and a bit higher for the ARIC study (77%). However, the authors state:
“In the young adults we studied with 4 retained third molars, periodontal pathology was incrementally greater on the third molars and progressively less on the second molars and on teeth more anterior to the molars…Almost all ARIC (98%) and Piedmont 65 (97%) subjects had periodontal pathology on more anterior teeth, at least one probing site of at least 4 mm in depth, or a clinical attachment level of at least 3 mm, which was greater than the prevalence on third molars.”
The authors do note that their younger patients may have have had their caries experience over or underreported and that the study population may not be representative of the US population. Nonetheless, they advise clinicians to reference their data when discussing with young patients about retaining or removing wisdom teeth. The authors conclude that the Piedmont 65 study suggests wisdom teeth can remain free of caries experience and periodontal pathology for a lifetime. However, they suggest due to the high amount of wisdom teeth affected by either caries and/or periodontal pathology that they are monitored regularly if retained and not extracted.