Hello, White patch on the buccal mucosa is commonly indicative of leucoplakia resulting from poor oral hygiene, repeated cheek or tongue biting or due to chewing certain nuts or leaves. He is suggested to maintain better oral hygiene, brushing teeth after every meal, rinsing the mouth and gargle with warm water with a pinch of salt at least three times a day. He should avoid addictions if any. Not all white patch are harmful some may be caused by friction of the teeth against the skin in the mouth.However, some can be pre-cancerous. Slanting palpebral fissure is commonly due to genetic or congenital disorder. He is suggested to clinically examined by an ENT to assess the type of white patch. He will be recommended to get few routine blood tests, urinalysis or biopsy if required to be done. He will be treated according to the severity of the symptoms and pathology detected. He may be referred to an Eye specialist for further investigations. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician