Backward-biting asymmetries, the most common lower-face asymmetry, were found to fluctuate randomly between the left and right sides of the face.
It can be reversed with multiple trips to the dentist, but according to a new research, your child’s crooked bite may indicate early life stress. The University of Washington investigators suggest that an asymmetric lower face is a novel marker that also captures early life stresses that occur after birth.
“Asymmetries in the skull and teeth have been used for decades by anthropologists to mark environmental stress, but they have only rarely been used in living populations,” said corresponding author Philippe Hujoel. “Such lower-face asymmetries can be assessed by looking at the dental bite in the permanent teeth, an exam that can be completed in seconds and with more certainty than a mother’s recall of birth weight and more ease than a search for a birth certificate,” he added.
Hujoel described a crooked or asymmetric bite as the teeth biting backward or forward on one side of the face and normally on the other side. Backward-biting asymmetries, the most common lower-face asymmetry, were found to fluctuate randomly between the left and right sides of the face. Such randomness is evidence for early life stress, he said.
Hujoel emphasised that crooked teeth, overbites and underbites are different than an asymmetric bite. Those conditions can be associated with asymmetric and symmetric bites, the latter of which is largely a reflection of genetics, not environmental stress, he said. “Lower-face asymmetries were common in a generation that became typified by an epidemic of diabetes and obesity in adulthood,” noted Hujoel, an adjunct professor of epidemiololgy in the School of Public Health.
Further research is needed to identify whether lower-face asymmetries are predictive of chronic diseases in living populations in the same way that skull asymmetries have been associated with degenerative diseases in long-deceased populations. The study appears in American Journal of Human Biology.