Abstract: An articulator provides for a wearer to bite it between the teeth in the upper jaw and the teeth in the lower jaw. The articulator includes an upper brace and a lower brace formed integrally; whereas, an occlusion unit is formed between the upper brace and the lower brace, thereby providing for biting by the wearer. The front edges of the upper brace and the lower brace are connected to a protector through a connector. When the wearer bites the articulator, the protector is disposed on an outer edge of the lips for protection. An exhalation opening is formed between the braces and the protector, and is provided with a movable plate that is flipped outward. Therefore, when the wearer bites the articulator, he or she can carry out a respiratory training by inhaling through the nose and exhaling through the mouth, thereby increasing the vital capacity effectively.