大方廣佛華嚴經疏 48.10

48.10

Seventh, the canine teeth have four marks, meaning left, right, upper, and lower, because there are four great canines. Thus when the Buddha entered nirvāṇa, the four canine teeth were not destroyed. "Cheek" (fu) means the cheek; it is also called the jawbone. Second, the upper canine tooth of the right cheek is named Meru to reveal that it is wondrous and high. In the fourth, there are three items including the milk of the Dharma: they share the single exposition of the Dharma. In terms of nourishing the dharmakāya, it is called "milk"; illuminating the myriad objects is called a "lamp"; causing them to be perfectly pure is "truth"—namely, expounding the Dharma of the three virtues of nirvāṇa, which also accomplishes the benefit of the three virtues of nirvāṇa.