Paired maxillary and smaller mandibular mouthguard for rugby player with malalignment.

A rugby player who had frequently experienced soft tissue injuries while playing rugby and wearing a conventional custom-made mouthguard came to the hospital clinic. The patient had suffered traumatic soft tissue injuries such as lip lacerations and bite trauma. Severe crowding due to ectopic maxillary and mandibular canines was observed. In response to the patient's request for better protection, a set of maxillary and mandibular mouthguards was designed: one covering the entire maxillary dentition and the other the mandibular front teeth only. The mouthguards were to be worn simultaneously. In this paper, we describe how these mouthguards were fabricated and discuss the results. The patient has experienced no injury to the stomatognathic system, including the lips, for five seasons since he began wearing this set of mouthguards. This new pairing of mouthguards appears to offer sufficient protection against injury, despite severe malalignment. We believe that this new type of paired maxillary and mandibular mouthguards has the potential to reduce sports-related dental injuries.

Influence of different post-core systems on impact stress: a pilot study.

UNLABELLED: This pilot study compared impact strain at the core and root surfaces between two different post-core systems. MATERIALS AND METHODS: The form of a bovine mandibular front tooth was modified to resemble that of a human maxillary incisor as a test specimen. A cast post and core (Metal PC) and composite resin and glass fiber-reinforced epoxy resin post (Fiber-Resin PC) system were tested. Four gauges were affixed to the buccal and lingual surfaces of the core and root. The specimens were then embedded in a metal mold using dental stone. A pendulum-type device with a pyramid-shaped metal impact object with a titanium alloy head was used to provide 2 different shock forces. Maximum distortion was measured and analyzed. RESULTS: Distortion at the core at each measurement point and total amount of distortion with Fiber-Resin PC was significantly greater (p<0.05) than that with Metal PC against both impact forces. On the other hand, distortion at the root at the buccal measurement point with Fiber-Resin PC was significantly less than that with Metal PC against both impact forces. Total distortion was significantly less with Fiber-Resin PC than that with Metal PC against the greater impact shock. Acceleration with Fiber-Resin PC was significantly less than that with Metal PC against both impact forces. CONCLUSION: Fiber-Resin PC has the potential to protect remaining root against traumatic force. This suggests that a Fiber-Resin PC is more suitable for non-vital teeth against not only occlusal but also traumatic impact force.