The work purpose to evaluate how the swimming could affect the skeletrical e dental structure of athlete due to the link of form and function. The athletes evacuate were 204, referred to nine Italian societies and 12 swimming pools. The athletes trained on average 7,7 + 3,5 times every week. A complete pathological analysis and one of hard and soft tissues of oral cavity followed by an intraoral examination. In the clinical analysis were evaluated: the occlusal state; the global conditions of the teeth; the presence or absence of dental erosions, discolorations and abrasions; the functionality of the tongue; the presence of disfunctions e problems of the Temporomandibular Joint (TMJ). The frontal breathing it’s associated to the specialists of frog swimming style, while the mono or bilateral breathing is noticed into the specialists of freestyle swimming (into the swimmers of dolphin style the 78% has frontal breathing and the 22% bilateral). The 69,6% of the swimmers keeps a low postural position of the tongue, that increases of percentage in athletes more evolved. A major symmetry is present in the symmetrical style (frog and dolphin style). A major asymmetry is present in monolateral breather. The swimming and the presence of malocclusion are directly related, especially in frequency and intensity with the passage of competition category. Breathing and style of swimming have an impact on mandibular shift and rotations.