Case of autoimmune neutropenia with severe marginal periodontitis

Early onset periodontitis is rarely seen in infants, though often leads to an acute and serious clinical course when encountered in such patients. Autoimmune neutropenia presents systemic and dental symptoms, as depressed resistance to bacterial infection is caused by a disorder that reduces the number of neutrophils. This disease can result in not only gingival inflammation but also destruction of periodontal tissues, such as attachment loss, alveolar bone absorption, and early tooth loss in primary as well as mixed dentition. Here, we report treatment of a child with marginal periodontitis from the age of 3 years–7 years 9 months. No systemic manifestations were noted until 3 years of age, thus the patient had never received a detailed examination or medication related to the disease. Following examinations at our department, we referred the patient to a pediatrician at our university hospital for possible systemic disease, who made a diagnosis of autoimmune neutropenia. Although administration of antibiotics and professional dental care were continued, neutrophil count was not increased and progressive periodontal destruction was observed. Extraction of teeth with poor prognosis was performed and a prosthetic strategy for the missing teeth developed. It is important to recognize that periodontitis along with autoimmune neutropenia can appear in infants, even though the incidence is quite low. Early detection and early treatment of this disease is necessary for delaying progression of periodontitis and optimal occlusal induction of permanent teeth.     

Predictors of oral health quality of life in older adults

There is limited information regarding oral health status and other predictors of oral health‐related quality of life. An association between oral health status and perceived oral health‐related quality of life (OHQOL) might help clinicians motivate patients to prevent oral diseases and improve the outcome of some dental public health programs. This study evaluated the relationship between older persons' OHQOL and their functional dentition, caries, periodontal status, chronic diseases, and some demographic characteristics. A group of 733 low‐income elders (mean age 72.7 ISD=4.71, 55.6% women, 55.1% members of ethnic minority groups in the U.S. and Canada) enrolled in the TEETH clinical trial were interviewed and examined as part of their fifth annual visit for the trial. OHQOL was measured by the Geriatric Oral Health Assessment Index (GOHAI); oral health and occlusal status by clinical exams and the Eichner Index; and demographics via interviews. Elders who completed the four‐year assessment had an average of 21.5 teeth (SD=6.9). with 8.5 occluding pairs (SD=4.6), and 32% with occlusal contacts in all four occluding zones. Stepwise multiple regressions were conducted to predict total GOHAI and its subscores (Physical, Social, and Worry). Functional dentition was a less significant predictor than ethnicity and being foreign‐bom. These variables, together with gender, years since immigrating, number of carious roots, and periodontal status, could predict 32% of the variance in total GOHAI, 24% in Physical, 27% in Social, and 21 % in the Worry subscales. These findings suggest that functional dentition and caries influence older adults' OHQOL, but that ethnicity and immigrant status play a larger role.     

Cementoblastoma related to a primary tooth: a case report

Cementoblastomas are benign lesions of the odontogenic ectomesenchyme that rarely occur related to the primary dentition, especially on the left side of the mandible. This study describes a case of a true cementoblastoma related to the left second primary mandibular molar in a 7-year-old child (the largest one seen in the left side of the mandible). Additionally, the radiographic and histologic findings of the lesion are described in details.     

骨水泥和种植体同期植入修复颌骨和牙列缺损的实验研究

目的：探讨高分子材料和种植体同期植入缺损区进行同步骨缺损修复和牙列缺损修复的可行性。方法：以4只杂种狗为研究对象，制备下颌骨长约2．5cm的缺损的动物模型(保留下颌骨下缘)，将骨水泥(聚甲基丙烯酸酯)植入骨缺损，同时将牙种植体植入骨水泥中并调整长轴方向，立即关闭术创。至术后3个月摄X线片，然后处死动物，局部巨检以了解骨水泥同骨组织的结合情况，并制备骨组织切片进行苏木精一伊红染色和甲苯胺蓝染色，以了解植入材料周边骨的生长情况及其对植入材料的反应。结果：术后3个月X线检查见骨缺损区充满骨水泥，骨水泥周边的骨小梁清晰，未见骨吸收或炎症表现，形成良好的骨-骨水泥界面，种植体则依赖其表面的螺纹结构与骨水泥间紧密的机械性嵌合而牢固的成为一体，植入的骨水泥块与周边天然骨结合紧密，无松动现象。植入材料周边局部脱钙骨的苏木精-伊红染色和甲苯胺蓝染色见骨结构正常，同时骨-骨水泥界有新骨形成。结论：骨水泥作为颌骨修复替代材料同期植入种植体是可行的。     

新型粘结固定桥临床应用初步观察

目的 观察一种用于牙列缺损永久修复的新型粘结固定桥的临床效果。方法 选择有单个或多个牙缺失的病人，进行固定桥基牙的牙周和特定的牙体预备。然后制作固定桥并试戴，用4－META／MMA－TBB树脂粘结剂粘结固定桥。结果 267例（304个）固定桥病人经二年以上随访，发现192个前牙桥中只有1个，112个后牙桥中只有2个脱落，其余固定桥稳定、功能良好。结论 采用树脂粘接技术，结合基牙的机械预备，能较好地克服3／4冠桥、桩冠桥和嵌体桥的缺陷，使之成为良好永久的修复体。     

多曲方丝对下颌中切牙牙周膜应力分布有限元分析

目的:对多曲方丝弓技术中打开咬合所产生的力学系统进行有限元分析,了解多曲方丝弓打开咬合时下颌中切牙牙周膜应力分布情况。方法:建立下颌牙列各牙齿、牙槽骨及切牙牙周膜的有限元模型。然后进一步模拟临床在中切牙处加载75g垂直向下的力,按照考虑或不考虑牙周膜的两种情况,求得牙周膜的应力分布。结果:两种情况下牙周膜部位最大值变化很大。在不考虑牙周膜时,牙根颈部应力最大值达21.6×105g/mm2;考虑牙周膜的缓冲作用时牙根及牙周膜上的应力分布相对均匀,且绝对值变小,但牙槽嵴顶部应力峰值明显变大。结论:①本研究建立的下颌牙列的三维有限元模型,比较符合实际情况,可以适用于多曲方丝弓矫治技术的研究。②多曲方丝弓作用下下颌中切牙牙周膜应力从颈缘到根尖逐渐减小,但在牙槽嵴顶部应力峰值明显增大,易出现牙周膜透明性变。     

Prevalence of dental erosion and related factors in the deciduous dentition of Japanese children

ObjectivesThe objectives of this study were to clarify the prevalence of dental erosion in the deciduous dentition of child patients, and to identify dietary habits and other factors related to dental erosion.MethodsA total of 116 weaned child patients (67 boys, 49 girls) aged 2–6 years who attended the outpatient pediatric dental clinic of a university hospital for treatment or a periodic checkup were included in the study. A questionnaire survey of the patients' dietary habits and a clinical examination were performed. Dentition was divided into four areas, and responses to erosion-related questions were evaluated for each area using multiple logistic regression analysis.ResultsThe prevalence of subjects with erosion, including pre-erosion lesions without tooth surface defects, was 86%; the prevalence of advanced erosion accompanied by tooth surface defects was 34%. Some food- and drink-related items were found to be significantly associated with erosion of the maxillary anterior teeth but not the mandibular teeth. Medication, use of fluoride, and past dental or medical history did not have any significant effect on erosion in any of the four areas.ConclusionsThe occurrence of dental erosion in deciduous dentition and factors related to its appearance were clarified for each area. An epidemiological survey is required to further reveal the state of deciduous dental erosion in Japanese children and to investigate the necessity of, and, if necessary, establish relevant guidelines for the prevention of dental erosion.