I think, as an overall, we must realize what is truly important, that is, the teaching will always be greater than the teacher. Even the Buddha is no comparison to the Dharma. Even on the Buddhas deathbed, when His disciples feared that the light-of-the-world was about to go-out, the Buddha reminded then of the power of the teaching. As long as the practices of the teachings continue, the light will always shine!!
The Buddha told Ananda that when the Dhamma has been completely forgotten a new fully enlightened Buddha will arise. He is called Maitreya. I'm here quoting Ven. Sri. Dhammananda when he says in his book What Buddhists Believe on page 76:
...The Buddha continued again: "I am not the first Buddha to come upon earth; nor shall I be the last. In due time, another Buddha will
arise in this world, a Holy One, a Supremely Enlightened One, endowed
with wisdom, in conduct auspicious, knowing the universe, an
incomparable leader of men, a master of devas and men. He will reveal
to you the same Eternal Truths which I have taught you. He will
proclaim a religious life, wholly perfect and pure; such as I now
"How shall we know him?", asked Ananda.
The Buddha replied, "He will be known as Maitreya which means kindness or friendliness."