Management of Crown-root Fracture with 180-degree Rotation Replantation: a Report of 2 Cases.

Intentional replantation involves a combination of periodontics, endodontics, prosthodontics and oral surgery. Crown-root fracture management is still complicated nowadays. A fracture line extending longitudinally to the subgingival area and intruding bioogical width could affect infection control, gingival health and crown restoration. In the present study, we present two cases. Case 1 involved a 23-year-old man who presented at our hospital with crown-root fracture of the maxillary left central incisor. A radiographic image of the tooth revealed a fracture line under the alveolar crest. The fractured tooth was treated with intentional replantation with 180-degree rotation, root canal treatment and veneer restoration. The patient was followed up for 60 months. The replanted tooth functioned well, and no symptoms of resorption or ankylosis were observed by radiographic examination. Case 2 involved a 20-year-old woman who was referred to our hospital for crown-root fracture of her maxillary teeth. A radiographic examination revealed complicated crown-root fracture of the maxillary right lateral incisor and both maxillary central incisors. The central incisors were treated with intentional replantation with 180-degree rotation. At the 48-month follow-up, the fractured teeth were found to have regained normal function based on clinical and radiographic examination. Limited case reports are available on a long-term follow-up of intentional replantation with 180-degree rotation. These two cases, particularly case 2, presented optimal healing after 4 years with unideal crown-root ratios. This case report suggests that this old method of preserving teeth with crown-root fractures can be used as a last resort to save teeth owing to its timesaving and microinvasive procedure.

[Epidemiological features of hand, foot and mouth disease in China, 2008 - 2009].

OBJECTIVE: To clarify the seasonal and geographical difference and pathogen patterns so as to provide reference of prevention and control of the disease through analyzing the epidemic characteristics of reported hand-foot-mouth disease (HFMD) cases in China, 2008 - 2009. METHODS: We analysed the epidemiological data of HFMD from the Chinese national notifiable infectious diseases reporting system in 2008 and 2009. RESULTS: There were 488 955 and 1 155 525 reported HFMD cases in 2008 and 2009, in China, of which 1165 and 13 810 were severe and 126 and 353 were fatal, respectively. The notification rates were 50.09/10 million, 68.47/10 million and 59.04/10 million in high, medium and low latitudes areas, respectively. The epidemic periods in Medium and Low latitude were from 12 to 24 weeks in 2009, and in high latitude it was from 23 to 35 weeks. HFMD cases were concentrated mainly in 5 year-old or even younger children, accounted for 92.23% of the total cases. The incidence rate of two years old appeared to be the highest. The features of severe and death case concentrated in lower age groups were more evident, and the proportion of severe case and case fatality rate under 1 years old was higher than that in other age groups. We also noticed that with the increasing of age, the proportion of severe case and case fatality rate had a decreasing trend. There was a difference between the pathogens seen. The relative risk (RR) for an human enterovirus 71 (HEV71) isolate was higher among severe case than in common cases (RR = 1.82), whereas the RR for an EV71 isolate was higher among the death cases than in common cases (RR = 2.11). There was seasonal variation of pathogen composition. There were 477 clusters of cases from 2008 to 2009, of which 389 found in preschools, 47 in rural villages, outbreaks of clusters were mainly from April to July. CONCLUSION: The HFMD epidemics was increasing in 2009. The epidemic of HFMD in different latitudes area and seasons was different. Children of five year old or under were the major population groups at risk, of HFMD. The younger ones had higher risk of becoming severe and death cases. HEV71 and coxsackievirus A16 were both the major etiologic agents of HFMD. The preschool and rural villages were the main settings of clusters of cases.

An outbreak of hand, foot, and mouth disease associated with subgenotype C4 of human enterovirus 71 in Shandong, China.

BACKGROUND: An outbreak of hand, foot, and mouth disease (HFMD) included 1149 people in Linyi City, Shandong Province, China, in 2007: three children died. OBJECTIVES: To characterize the pathogens responsible for this outbreak and to analyze their genetic features. STUDY DESIGN: A total of 233 clinical specimens were collected from 105 hospitalized patients, including 11 patients with severe HFMD. Virological investigations (direct RT-PCR, viral isolation and molecular identification) and phylogenetic analysis were performed. RESULTS: Human enterovirus 71 (HEV71) was the main pathogen that caused this outbreak, based on clinical manifestations, epidemiological data, and laboratory results. Phylogenetic analysis indicated that the Shandong HEV71 isolates belonged to 3 lineages in subgenotype C4. Subgenotype C4 could be further divided into two clusters (C4a and C4b), which corresponded to two time periods. Cluster C4a HEV71 has been the predominant virus circulating in mainland China in the past 5 years. CONCLUSIONS: The 2007 HFMD outbreak was mainly caused by HEV71 subgenotype C4 with 3 transmission chains. This virus has been continuously circulating in China since 1998. The Shandong strains co-evolved with isolates from other provinces in mainland China and neighboring countries.