ENOfficial
Ibn `Abbas said: God's messenger had spaces between his front teeth, and when he talked something like light seemed to come out between his front teeth. Darimi transmitted it.
Source: sunnah.com
Other translations
Arabic
عَنِ ابْنِ عَبَّاسٍ قَالَ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَفْلَجَ الثَّنِيَّتَيْنِ إِذَا تَكَلَّمَ رُئِيَ كَالنُّورِ يَخْرُجُ مِنْ بَيْنِ ثَنَايَاهُ. رَوَاهُ الدَّارمِيّ
sunnah.com