Читать книгу Shear's Cysts of the Oral and Maxillofacial Regions - Paul M. Speight - Страница 39

Figure 3.3 shows that radicular cysts may arise at any site in the jaws, but are more common in the maxilla (60%) than the mandible, with a particularly high frequency in the anterior maxilla, with about 40–50% of all cases occurring in this region. There are a number of possible reasons for this. First, in addition to the hazard posed by dental caries, maxillary incisors have in the past, perhaps more frequently than other teeth, had silicate restorations placed in them, with consequent high risk to their pulps. If this were the cause, then the prevalence of cysts at this site might reduce in future generations. Second, there is a high prevalence of palatal invaginations in the maxillary lateral incisors and a high frequency in which pulp death supervenes in these teeth. Third, maxillary anterior teeth are probably more prone than others to traumatic injuries, which may lead to pulp death.

Figure 3.3 Site distribution of radicular cysts. A comparison of 1111 cases from South Africa (Johannesburg) and 1974 cases from England (Sheffield).

Recent studies, however, show that this site distribution is seen across the world and has not changed in the last two decades, suggesting that trauma and susceptibility to caries may be the main reasons. The proportion of radicular cysts associated with the maxillary incisors has been reported to be 54.4% in India (Ramachandra et al. 2011 ), 52.8% in England (Jones et al. 2006 ), 47.8% in Turkey (Soluk Tekkeşin et al. 2012b ), 37.3% in Iran (Sharifian and Khalili 2011 ), 36.4% in Sicily (Tortorici et al. 2008), and 43% in Brazil (Tavares et al. 2017 ). Most studies agree that the mandibular molar area is the next most common site.