An interesting large sample, retrospective study can be found at the "ahead of print" at the Angle Orthodontist website.
The study is from Oslo University, Norway, and it is a collaboration of the perio and orthodontic departments.
A sample of 588 patients was analyzed, with intraoral photos, plaque accumulation, inflammation, and cephalometric measurements (A-Pog, Incisors inclination, ML-NSL, NL-NSL) regarding the mandibular incisors recessions. The Miller classification was used.
Conclusions:
- 10,3% of the cases were found with recessions: 8,6% Miller Class I and 1,7% Miller Class II. That is not a very large prevalence.
- In the presence of gingival recession, retroclination of the mandibular incisors in cases of mesial basal relation (Angle Class III) seems to increase the risk of a more severe gingival recession.
- Keeping the gingiva in the mandibular frontal area as healthy as possible during orthodontic treatment appears to be the determinant in the development of gingival recession. Inflammation seems to be a contributory factor for this condition. A careful examination of the buccal gingiva in the lower incisors, before deciding the amount of movement of these teeth, seems important.
D.G.