I want to highlight something that I think may be contributing to the development of Exfoliative Chelitis in some people which I haven’t heard mentioned before in my research of the condition (either in academic papers or in forums on the internet).
I think Exfoliative Chelitis is likely multi-factorial so this may not explain all instances of the condition, but I want to highlight this as a possible contributory factor.
I think there may be a correlation between exfoliative chelitis and incorrect jaw development (the technical term for this is malocclusion).
How many of you have misaligned jaws?
There are two main forms of jaw misalignment (malocclusion). The first is an overbite (which means the upper front teeth overlap the lower teeth because your lower jaw is positioned too far back from your upper jaw). The second is an underbite (which means the lower teeth overlap the upper teeth because the lower jaw is positioned too far forward)? It would really be useful to know how many people have malocclusion commenting here and whether it is mild or severe. Severe overbites are related to conditions like TMJ so you can be pretty sure you have an overbite if you have TMJ.
So what can exfoliative chelitis possibly have to do with jaw development?
Well, it comes down to a thing called lip competence.
According to Satimary Endo Leonardo, Yoshiaki Sato, , Tomoo Kaneko, Takaaki Yamamoto, Kaori Handa, Junichiro Iida “a patient is described as having competent lips when the lips are in light contact at the clinical rest position [and an almost involuntary effort is required to hold the lips together. In individuals with incompetent lips, distinguishable activity of the lower lip and unusual movement of the tongue are needed to close the lips. According to Yamaguchi et al. , lip incompetence must be shown to refer to a functional problem of the lips” (Differences in dento-facial morphology in lip competence and lip incompetence). So, lip competence has to do with how the lips are sealed (held together) at rest. If you need a bit of effort to hold your lips together at rest (and without any muscle action your lips would rest a couple of millimetres apart say) then you have poor lip competence. Lip competence is also related to jaw development (occlusion) because how the jaws develop during childhood impacts the bone structure of the face and thus the relative position of the upper and lowe lips.
It it generally thought that jaw development is hereditary but it has been shown that it is influenced by environmental factors like mouthbreathing in childhood. I won’t go into the research behind this here but I will just say, that if you mouth breathe in your childhood, it can impact your facial and jaw development, meaning you end up with misaligned jaws, which in turn effects 'lip competence'. See an article titled "Mouth breathing: Adverse effects on facial growth, health, academics, and behaviour" by Yosh Jefferson, DMD, MAGD for reference.
So how could lip competence be related to exfoliative chelitis?
Well I think this condition might be caused in part by a slight structural misalignment between the wet/dry lip border of the lips (the line where the wet mucosa starts and the red lip ends).
Does your crusting start forming on the inner lips at first - that line inside your mouth where the mucous membrane transitions to the dry outer lip ?
Do people here get “white gunky buildup” inside the mouth on the inner lips area (the transitional wet/dry zone of the lips)?
I have worked out that this “white gunky buildup” is actually detached flakes of mucous membrane skin that has become too dry and then got moistened again with saliva (it is effectively dead mucous membrane skin).
So why is this relevant?
I think that, in EC, the inner lip area dries out (the wet/dry border part dries and becomes crusty) because, due to jaw misalignment, the upper and lower lips are not properly aligned, meaning the seal from the air is imperfect.
Because the wet and dry border of the upper lip is not meeting correctly with the wet and dry border of the lower lip, the mucous membrane there starts drying out.
I actually think the crusting is caused by the wet/ dry border of the lip is going through cycles of being too dry (from contact with the air) and then getting moist again (from saliva).
If you have misaligned jaws, when you sleep, during the night, because of the poor jaw alignment, you will certainly sleep with your mouth open. This means that the inner lips are exposed to air all night long, so they dry out. Then, in the day, because you close your mouth (though with some effort, if you have lip competence issues), the inner lip area inside your mouth gets moistened with saliva again. However, because it has dried out throughout the night, when it gets moistened with saliva, the dried flakes become soggy and loose and form into the ‘white gunk’ (dead mucous membrane skin). So, effectively, the top layer of skin from that wet/dry border on the lip is eroded away. Because it gets eroded, it starts forming into a crust. Because this happens again and again, in the same pattern every day, the crusts build and build over time until they have grown sufficiently big that the skin underneath them heals to an extent that the crust can fall off. However, because the lip seal is imperfect anyway, having the mouth closed doesn’t exactly protect the mucuous membrane entirely from the air, so it causes ongoing irritation.
So what I'm saying is, I think EC can be caused by a sort of structural issue with the lip anatomy as a consequence of jaw development.
This isn’t likely the only causative factor for exfoliative chelitis but I think it may be one of them. I think exfoliative chelitis might be caused by mutiple factors which cause the lip skin to become too dry (like, for example accutane medication or hypothyroidism). Probably these factors are additative. But I think this lip cometence issue seems to be a factor in my case and was wondering whether other people experienced this as well.
Would appreciate if people could respond with their thoughts.