I'm guessing the Lichen Plantus is not related to the MMS treatment - given the information below. I'm with Mac on this.
From PubMed:
Lichen planus is a disease in which there is an itchy rash on the skin or in the mouth.
Causes, incidence, and risk factors:
The exact cause of lichen planus is unknown. However, it is likely to be related to an allergic or immune reaction.
Risks include:
Exposure to medications, dyes, and other chemical substances (including gold, antibiotics, arsenic, iodides, chloroquine, quinacrine, quinide, phenothiazines, and diuretics)
Disorders such as hepatitis C
Lichen planus generally affects middle-aged adults. It is less common in children.
Symptoms
Mouth lesions
Tender or painful (mild cases may have no discomfort)
Located on the sides of the tongue or the inside of the cheek
Sometimes located on the gums
Area of blue-white spots or "pimples"
Lines of lesions that form a lacy-looking network
Gradual increase in size of the affected area
Lesions sometimes form painful ulcers
Skin lesions:
Usually located on the inner wrist, legs, torso, or genitals
Itchy
Even on both sides (symmetrical)
Single lesion or clusters of lesions, often at sites of skin injury
Papule 2 - 4 cm in size
Papules clustered into a large, flat-topped lesion
Lesions have distinct, sharp borders
Possibly covered with fine white streaks or scratch marks called Wickham's striae
Shiny or scaly appearance
Dark colored -- reddish-purple (skin) or gray-white (mouth)
Possibility of developing blisters or ulcers
Other symptoms include:
Dry mouth
Hair loss
Metallic taste in the mouth
Ridges in the nails (nail abnormalities)
Signs and tests
The health care provider may make the diagnosis based on the appearance of the skin or mouth lesions.
A skin lesion biopsy or biopsy of a mouth lesion can confirm the diagnosis. Blood tests may be done to rule out hepatitis.
Treatment
The goal of treatment is to reduce your symptoms and speed healing of the skin lesions. If symptoms are mild, you may not need treatment.
Treatments may include:
Antihistamines
Immune-suppressing medications, such as cyclosporine (in severe cases)
Lidocaine mouthwashes -- to numb the area and make eating more comfortable (for mouth lesions)
Topical corticosteroids (such as clobetasol) or oral corticosteroids (such as prednisone) -- to reduce swelling and suppress immune responses. Corticosteroids may be injected right into a lesion.
Topical retinoic acid cream (a form of vitamin A) and other ointments or creams -- to reduce itching and swelling and aid healing
Topical immune-suppressing medications, such as tacrolimus and pimecroliumus -- but lesions must be watched carefully for signs of cancer
Dressings may be placed over topical medications to protect the skin from scratching.
Ultraviolet light therapy may be helpful in some cases.
Oral retinoids (acitretin)
Expectations (prognosis)
Lichen planus is usually not harmful and may get better with treatment. It usually clears up within 18 months.
However it may last for weeks to months, and may come and go for years. It usually clears up within 18 months.
If lichen planus is caused by a medication, the rash should go away once the medicine is stopped.
Complications
Mouth ulcers that are there for a long time may develop into oral cancer.
Calling your health care provider
Call your health care provider if:
Your symptoms continue
The skin or mouth lesions change in appearance
The condition continues or worsens even with treatment
Your dentist recommends adjusting your medications or treating conditions that trigger the disorder
References