This study evaluated, over a 4-month study period, the amount of apical root resorption occurring in maxillary central incisors following their retraction when employing either micro-implant or J-hook headgear anchorage. The prospective randomised clinical trial was conducted in Orthodontic Clinic, College of Stomatology, China from 2008-2009. Subjects are patients requiring fixed appliances on waiting list (n=20). In female Han Chinese patients aged from 16-26 years, standardized periapical radiographs from 10 randomly assigned patients with maxillary protrusions comprising the micro-implant group, and from 10 similar patients comprising the J-hook headgear group, were assessed for maxillary central incisor apical root resorption. Measurements before and after orthodontic therapy were also obtained from lateral cephalometric radiographs to calculate incisor horizontal retraction and vertical intrusion distances. Estimated retraction force vectors were calculated in horizontal and vertical directions for both treatment groups. Data analysis employed t-tests and the Pearson correlation test, with α=0.05 for statistical significance. The results showed that when compared with the J-hook group, significantly more apical root resorption shortening of the maxillary central incisors was observed in the micro-implant group (1.27 mm difference, 95% CI=0.70-1.84, P<0.001), which was associated with a significantly larger retraction distance (P=0.004) and a smaller vertical force component (P<0.0001). We are led to conclude that continuous activation of the nickel-titanium coil springs used in the micro-implant group resulted in significantly more apical root resorption shortening and maxillary central incisor retraction than when intermittent J-hook retraction was employed. The employment of continuous duration orthodontic forces presents a risk for increased apical root resorption that requires careful radiographic monitoring.

OBJECTIVETo evaluate the clinical effects of filling for radiation carious cavities.

METHODS146 carious cavities of 15 patients after radiotherapy for head and neck malignancies were included and were filled with two new GIC (Ketac-Molar and Fuji IX). The 2 years follow-up results were evaluated with USPHS evaluation criterion.

RESULTS(1) The 2 years excellent rates were 51.7% in Ketac-Molar and 52.3% in Fuji IX, no significant differences. (2) Failures and defects were mainly occurred after 1 and 2 years. The main reason of failure was loss of filling. Marginal staining was a common shortcoming of the two materials. (3) There were no significant differences in main indexes except retention.

CONCLUSIONSIt is successful for radiation caries to be filled with Ketac-molar and Fuji IX, and is practically significant in stomatological clinic.

Adult ; Aged ; Cranial Irradiation ; adverse effects ; Dental Caries ; etiology ; pathology ; therapy ; Dental Restoration, Permanent ; methods ; statistics & numerical data ; Female ; Follow-Up Studies ; Glass Ionomer Cements ; Head and Neck Neoplasms ; radiotherapy ; Humans ; Male ; Middle Aged ; Time Factors ; Treatment Outcome

This study evaluated, over a 4-month study period, the amount of apical root resorption occurring in maxillary central incisors following their retraction when employing either micro-implant or J-hook headgear anchorage. The prospective randomised clinical trial was conducted in Orthodontic Clinic, College of Stomatology, China from 2008-2009. Subjects are patients requiring fixed appliances on waiting list (n=20). In female Han Chinese patients aged from 16-26 years, standardized periapical radiographs from 10 randomly assigned patients with maxillary protrusions comprising the micro-implant group, and from 10 similar patients comprising the J-hook headgear group, were assessed for maxillary central incisor apical root resorption. Measurements before and after orthodontic therapy were also obtained from lateral cephalometric radiographs to calculate incisor horizontal retraction and vertical intrusion distances. Estimated retraction force vectors were calculated in horizontal and vertical directions for both treatment groups. Data analysis employed t-tests and the Pearson correlation test, with α=0.05 for statistical significance. The results showed that when compared with the J-hook group, significantly more apical root resorption shortening of the maxillary central incisors was observed in the micro-implant group (1.27 mm difference, 95% CI=0.70-1.84, P<0.001), which was associated with a significantly larger retraction distance (P=0.004) and a smaller vertical force component (P<0.0001). We are led to conclude that continuous activation of the nickel-titanium coil springs used in the micro-implant group resulted in significantly more apical root resorption shortening and maxillary central incisor retraction than when intermittent J-hook retraction was employed. The employment of continuous duration orthodontic forces presents a risk for increased apical root resorption that requires careful radiographic monitoring.
Adult ; Dental Implants ; Female ; Humans ; Incisor ; diagnostic imaging ; Maxilla ; diagnostic imaging ; Orthodontic Anchorage Procedures ; instrumentation ; methods ; Prospective Studies ; Radiography ; Root Resorption ; diagnostic imaging ; Tooth Apex ; diagnostic imaging ; Young Adult

OBJECTIVETo review and analyze the history and current situation of stomatological journals in China from 1949 to 2009.

METHODSThe data from journal database, web sites and yearbooks were collected, and the information on Chinese dental journals, national economic indicators and the development in dental disciplines from 1949 to 2009 were obtained.

RESULTSThe dental journals numbered one kind, four issues in 1949 and 32 kinds, 204 issues in 2009. China's gross domestic product (GDP) was from 67.9 billion Yuan in 1949 to 30.067 trillion Yuan in 2008.

CONCLUSIONSThe quantity of stomatological journals in China has increased remarkably over the past 60 years.

Bibliometrics ; China ; Economics ; History, 20th Century ; History, 21st Century ; Oral Health ; Oral Medicine ; Periodicals as Topic ; history ; Socioeconomic Factors

This case report describes the diagnosis and endodontic therapy of maxillary fused second and third molars, using cone-beam computed tomography (CBCT). A 31-year-old Chinese male, with no contributory medical or family/social history, presented with throbbing pain in the maxillary right molar area following an unsuccessful attempted tooth extraction. Clinical examination revealed what appeared initially to be a damaged large extra cusp on the buccal aspect of the distobuccal cusp of the second molar. However, CBCT revealed that a third molar was fused to the second molar. Unexpectedly, the maxillary left third molar also was fused to the second molar, and the crown of an unerupted supernumerary fourth molar was possibly also fused to the apical root region of the second molar. Operative procedures should not be attempted without adequate radiographic investigation. CBCT allowed the precise location of the root canals of the right maxillary fused molar teeth to permit successful endodontic therapy, confirmed after 6 months.
Adult ; Cone-Beam Computed Tomography ; methods ; Follow-Up Studies ; Fused Teeth ; diagnostic imaging ; Humans ; Image Processing, Computer-Assisted ; methods ; Imaging, Three-Dimensional ; methods ; Male ; Maxilla ; Molar ; abnormalities ; Molar, Third ; abnormalities ; Pulpitis ; diagnostic imaging ; Root Canal Therapy ; Tooth Root ; abnormalities ; Tooth, Supernumerary ; diagnostic imaging ; Tooth, Unerupted ; diagnostic imaging