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A controlled study of the association of various dental anomalies with hypodontia of permanent teeth 总被引:1,自引:0,他引:1
Although hypodontia, or oligodontia, is one of the most common human dental anomalies observed, there have been few studies on the association of other anomalies occurring with it. The present investigation of 1032 patient records found that 65.7% of patients with hypodontia showed ankylosis of primary molars compared to only 1.5% of control children (P less than 0.001). In addition, taurodontism of the mandibular first permanent molar was observed in 34.3% of hypodontia cases compared to 7.1% in the controls (P less than 0.001). Other dental anomalies significantly associated with hypodontia include enamel hypoplasia (11.9%, P less than 0.01) and conical incisors (8.9%, P less than 0.01). In contrast, there were significantly more impacted teeth in control children compared to the hypodontia group. The results indicate that for patients with missing permanent teeth, clinicians should be alert to the possibility of these associated anomalies and their accompanying clinical implications. 相似文献
3.
BACKGROUND: The aim of this study was to compare the dental health of children with gastro-esophageal reflux disease (GERD) with a healthy control group. METHODS: Dental examinations were conducted for 52 children (31 boys and 21 girls) with a definitive history of GERD. For every subject enrolled in the study, a healthy control sibling without the condition was recruited. Medical histories were obtained from medical records, and dental and dietary histories were obtained from parents. The teeth were examined for erosion, dental caries, and enamel hypoplasia, and sampled for Streptococcus mutans. RESULTS: The prevalence of erosion by teeth was found to be statistically significant between GERD patients (14 per cent) and controls (10 per cent) (p<0.05). GERD patients had erosion in more permanent teeth compared to controls (4 per cent vs 0.8 per cent, p<0.05), and more severe erosion (p<0.05). Caries experience was also higher in GERD patients compared to controls (p<0.05). Although there were more subjects with Streptococcus mutans in the GERD group compared to the control group (42 per cent vs 25 per cent), the difference was not statistically significant. CONCLUSIONS: Children with GERD have more erosion and dental caries compared to healthy controls and should be targeted for increased preventive and restorative care. 相似文献
4.
PURPOSE: The purpose of this longitudinal study was to determine factors associated with mutans streptococci (MS) infection and development of caries lesions in a group of children 21 to 72 months old. METHODS: The 63 caries-free children, recruited since birth, were divided into: (1) a study group of 24 children who were colonized with MS; and (2) a control group of 39 children without MS. The children were recalled every 3 months for approximately 24 months, and their social, medical, and dental histories were updated. At each recall, the teeth were checked for presence or absence of plaque, enamel hypoplasia, and caries lesions, and their MS status was assessed using a commercial test kit. RESULTS: MS infection was associated with: (1) visible plaque (P < .01); (2) enamel hypoplasia (P < .05); (3) commencement of tooth-brushing after 12 months of age (P < .05); (4) lack of parental assistance with tooth-brushing (P < .025); and (5) increased hours of child care/school (P < .05). Four children (20%) were colonized at an age range of 21 to 36 months, 9 (45%) at 37 to 48 months, and 7 (35%) at 49 to 72 months (P < .001). Eight children who developed caries lesions: (1) had more hypoplastic teeth (P < .001); (2) ate sugar-containing snacks (P < .05); and (3) did not brush regularly with chlorhexidine gel (P < .01) compared to those who remained free of caries lesions. CONCLUSIONS: Lack of oral hygiene, consumption of sugar-containing snacks, and enamel hypoplasia are significant factors for both MS infection and caries lesion initiation. 相似文献
5.
Neonatal laryngoscopy and endotracheal intubation often are required for prematurely born, low birthweight children. Previous studies have shown that these procedures are associated with a high prevalence of enamel hypoplasia of the maxillary anterior teeth. The present case report, which describes dilaceration of a left maxillary primary central incisor probably resulting from laryngoscopy, strongly supports the hypothesis that irreversible trauma to the dentition may result from endotracheal intubation. 相似文献
6.
PURPOSE: This laboratory study compared visual-tactile examination with conventional radiographs, digital radiographs, and laser fluorescence in the detection of occlusal occult caries on extracted premolar teeth. METHODS: Extracted premolars without obvious caries or restorations were collected from school dental clinics. Occlusal surfaces of 320 extracted premolars were examined visually with an explorer, then examined using the KaVo Diagnodent unit and scored using specific criteria. The teeth were exposed using conventional and digital radiography, respectively. The radiographs were assessed for dentin radiolucencies beneath the occlusal surface. RESULTS: Of the 320 teeth used in this study, 302 were scored as sound by visual-tactile examination. Of these, 57 (19%) demonstrated dentin radiolucency on conventional bite-wings, and 245 (81%) were scored as radiographically sound. Thus, the sensitivity and specificity values of the visual-tactile examination compared with conventional radiography were 81% and 44%, respectively. In contrast, Diagnodent produced results of 82% sensitivity and 36% specificity when compared with conventional radiography. When compared to digital radiography, the sensitivity and specificity values of the visual-tactile examination were 90% and 44%, respectively. In contrast, when compared to digital radiography, Diagnodent showed a very low specificity of only 32%, although sensitivity was still high at 91%. Differences in specificity among the techniques were statistically significant (P < .03), whereas differences in sensitivity were not (P > .01). CONCLUSIONS: Although the diagnosis of occult dentinal caries may be further enhanced by the Diagnodent, a combination of visual-tactile examination and either conventional or digital radiography should identify over 80% of lesions. 相似文献
7.
Although Down syndrome children are known to be greatly predisposed to periodontal disease when compared with normal children, the preventive dental health practices of non-institutionalized Down syndrome children have not been well reported. This questionnaire study of 25 Down syndrome children aged 1-14 years compared with 25 normal control children showed that Down syndrome children have poorer dental health practices compared with normal children. Significantly greater numbers of Down syndrome children were weaned from the bottle at greater than 18 months of age (56% vs 24%, p less than 0.05) or had taken a bottle to bed (40% vs 12%, p less than 0.05), indicating their increased risk for the development of nursing bottle caries. In addition, Down syndrome children were receiving less help during tooth brushing (60% vs 84%, p less than 0.05), were older when they first visited the dentist, and less likely to be taking regular fluoride supplements. These results indicate that Down syndrome children are further disadvantaged by poor preventive dental health practices and should be targeted for increased preventive dental care. 相似文献
8.
SJ Smith CV Rahman PA Clarke AA Ritchie TW Gould JH Ward KM Shakesheff RG Grundy R Rahman 《Annals of the Royal College of Surgeons of England》2014,96(7):495-501
Introduction
The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.Methods
Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.Results
Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.Conclusions
Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models. 相似文献9.
Non‐invasive assessment of kidney allograft fibrosis with shear wave elastography: A radiological‐pathological correlation analysis 下载免费PDF全文
Maggie KM Ma Helen KW Law Kin Sun Tse Kwok Wah Chan Gary CW Chan Desmond YH Yap Maggie MY Mok Lorraine PY Kwan Sydney CW Tang Bo Ying Choy Tak Mao Chan 《International journal of urology》2018,25(5):450-455
Objectives
To evaluate the use of shear wave elastography in assessment of kidney allograft tubulointerstitial fibrosis.Methods
Shear wave elastography assessment was carried out by two independent operators in kidney transplant recipients who underwent allograft biopsy for clinical indications (i.e. rising creatinine >15% or proteinuria >1 g/day). Allograft biopsies were interpreted by the same pathologist according to the 2013 Banff Classification.Results
A total of 40 elastography scans were carried out (median creatinine 172.5 μmol/L [interquartile range 133.8–281.8 μmol/L]). Median tissue stiffness at the cortex (22.6 kPa [interquartile range 18.8–25.7 kPa] vs 22.3 kPa [interquartile range 19.0–26.5 kPa], P = 0.70) and medulla (15.0 kPa [interquartile range 13.7–18.0 kPa] vs 15.6 kPa [interquartile range 14.4–18.2 kPa]) showed no significant differences between the two observers. Interobserver agreement was satisfactory (intraclass correlation coefficient of the cortex 0.84, 95% CI 0.70–0.92 and intraclass correlation coefficient of the medulla 0.88, 95% CI 0.78–0.94). The areas under the receiver operating characteristic curves for detection of tubulointerstitial fibrosis were estimated to be 0.75 (95% CI 0.61–0.89), 0.85 (95% CI 0.75–0.95) and 0.65 (95% CI 0.53–0.78) for cortical, medullary tissue stiffness and serum creatinine, respectively.Conclusions
Shear wave elastography can be used as a non‐invasive tool to evaluate kidney allograft fibrosis with reasonable interobserver agreement and superior test performance to serum creatinine in detecting early tubulointerstitial fibrosis. 相似文献10.
Zhiwen J. Lo Xuxin Lim Diane Eng Josip Car Qiantai Hong Enming Yong Li Zhang Sadhana Chandrasekar Glenn W. L. Tan Yam M. Chan Seow C. Sim Chien W. Oei Xiaojin Zhang Ayliana Dharmawan Yi Z. Ng Keith Harding Zee Upton Chun W. Yap Bee H. Heng 《International wound journal》2020,17(3):790-803
The aim of this study is to evaluate the clinical and economic burden of wound care in the Tropics via a 5‐year institutional population health review. Within our data analysis, wounds are broadly classified into neuro‐ischaemic ulcers (NIUs), venous leg ulcers (VLUs), pressure injuries (PIs), and surgical site infections (SSIs). Between 2013 and 2017, there were a total of 56 583 wound‐related inpatient admissions for 41 461 patients, with a 95.1% increase in wound episodes per 1000 inpatient admissions over this period (142 and 277 wound episodes per 1000 inpatient admissions in 2013 and 2017, respectively). In 2017, the average length of stay for each wound episode was 17.7 days, which was 2.4 times that of an average acute admission at our institution. The average gross charge per wound episode was USD $12 967. Among the 12 218 patients with 16 674 wound episodes in 2017, 71.5% were more than 65 years of age with an average Charlson Comorbidity Index (CCI) of 7.2. Half (51.9%) were moderately or severely frail, while 41.3% had two or more wound‐related admission episodes. In 2017, within our healthcare cluster, the gross healthcare costs for all inpatient wound episodes stand at USD $216 million within hospital care and USD $596 000 within primary care. Most NIU patients (97.2%) had diabetes and they had the most comorbidities (average CCI 8.4) and were the frailest group of patients (44.9% severely frail). The majority of the VLU disease burden was at the specialist outpatient setting, with the average 1‐year VLU recurrence rate at 52.5% and median time between healing and recurrence at 9.5 months. PI patients were the oldest (86.5% more than 65 years‐old), constituted the largest cohort of patients with 3874 patients at an incidence of 64.6 per 1000 admissions in 2017, and have a 1‐year all‐cause mortality rate of 14.3%. For SSI patients, there was a 125% increase of 14.2 SSI wound episodes per 1000 inpatient admissions in 2013 to 32.0 in 2017, and a 413% increase in wound‐related 30‐day re‐admissions, from 40 in 2013 (4.1% of all surgeries) to 205 (8.3% of all surgeries) in 2017. The estimated gross healthcare cost per patient ranges from USD $15789–17 761 across the wound categories. Similar to global data, there is a significant and rising trend in the clinical and economic burden of wound care in Tropics. 相似文献