Measuring inequalities in the distribution of dental caries

Abstract – Objectives: To evaluate different measurements of prevalence and inequality in the distribution of dental caries as to their partial collinearity, and ability in expressing associations with the supply of fluoridated tap water, indices of socioeconomic status and provision of dental services. Methods: The DMFT, the Significant Caries (SiC) Index, the proportions of children with high- (DMFT ≥ 4) and rampant- (DMFT ≥ 7) caries experience, caries-free children (DMFT = 0), the Gini coefficient and the Dental Health Inequality Index (DHII) were the dental outcomes appraised in a sample comprising 18 718 oral examination records for 11- and 12-year-old schoolchildren in 131 towns of the state of São Paulo, Brazil. Spatial data analysis assessed the association between aggregate figures of dental indices and several covariates. Results: The DMFT, the SiC Index and the proportions of children with high- and rampant-caries experience presented strong linear associations (Pearson r near or higher than 0.95), and an analogous profile of correlation with indicators of socioeconomic status, dental services and access to fluoride tap water. The same was observed for the DHII, the Gini coefficient and the proportion of caries-free children. These observations involve the perception of variables in each set as interchangeable tools for ecological studies assessing factors influencing, respectively, prevalence levels and inequality in the distribution of dental disease. Conclusion: An improved characterization of the skewed distribution of caries experience demands the concurrent estimation of figures of prevalence and inequality in dental outcomes. This strategy may contribute to the design of socially appropriate programmes of oral health promotion.     

Root contact during insertion of miniscrews for orthodontic anchorage increases the failure rate: an animal study

OBJECTIVES: Miniscrews and miniplates are increasingly being used for absolute anchorage during orthodontic treatment. However, potential problems of damaging adjacent roots and their consequences during mini-implant placement in the alveolar process have not been clearly described. MATERIALS AND METHODS: Animal experiments were used to evaluate the stability of miniscrews placed with intentional root contact. The root repair was evaluated after screw removal. Seventy-two miniscrews were surgically placed in the mandibular alveolar bone of six adult mongrel dogs with metabolic bone labeling at 3-week intervals. Miniscrews of the experimental group were placed so that they contacted the root of the adjacent teeth, were retained for different time durations, and were then removed. The insertion torque, clinical measurements, removal torque, and histological findings were analyzed. RESULTS: (1) miniscrews contacting the roots showed a significantly higher insertion torque than those without contact; (2) there was a significant difference in the removal torque measurements based on the mobility of miniscrews and the state of root contact; and (3) miniscrews contacting the root were at greater risk of failure. CONCLUSIONS: During placement of miniscrews in the aveolar process, increased failure rates were noticed among those contacting adjacent roots. Failed miniscrews appeared to be surrounded with a greater volume of soft tissue. When more inflammation was present, the adjacent roots seemed to experience more resorption. Nevertheless, the created lesion was repaired with a narrow zone of mineralized tissue deposited on the root surface, which was likely cellular cementum, and was mainly filled with alveolar bone, with the periodontal ligament space being maintained.     

The impact of early palatal obturation on consonant development in babies with unrepaired cleft palate.

OBJECTIVE: The purpose of this investigation was to determine whether palatal obturators enhance consonant development during babbling for babies with unrepaired cleft palate. PARTICIPANTS: Fourteen babies with cleft palate who had worn anterior palatal obturators prior to palatal surgery were matched to 14 unobturated babies according to cleft type, sex, and age at time of presurgical evaluation. MAIN OUTCOME MEASURES: Spontaneous vocalizations of the obturated and unobturated groups were compared to determine whether differences were evident in size of consonant inventory as well as place and manner of consonant production. RESULTS: Paired t tests revealed no significant differences between the groups in size of consonant inventory or place and manner of consonant production. There was a trend for babies in the obturated group to produce more glottal consonants. CONCLUSIONS: In general, the findings of this study suggested that palatal obturators do not appear to facilitate production of anterior palatal consonants during babbling.     

Hypodontia and hyperdontia of permanent teeth in Hong Kong schoolchildren

This study was performed to determine the prevalence of hypodontia and hyperdontia of permanent teeth amongst Southern Chinese children in Hong Kong. The sample consisted of 1093 12-yr-old children on whom a panoramic radiograph was taken. The prevalence of congenitally missing teeth (third molars excluded) was 6.1% in boys, 7.7% in girls, and 6.9% for both sexes combined. On the average, each child was missing 1.5 teeth. The most commonly absent tooth was the mandibular incisor, affecting 58.7% of the children with hypodontia. Thirty children (2.7%) had supernumerary teeth, with a male:female ratio of 6.5:1; in four cases the tooth had erupted. Three children had fourth molars and one case of a supplemental premolar was recorded (all unerupted). Four cases of a maxillary supernumerary tooth and hypodontia in the mandible were seen.     

Family matters: Influence of biology and behavior on oral health

The family influences the oral health of other family members through biologic and behavioral factors and their interactions over the lifespan. Community and environmental factors also influence oral health. These factors are described and examples are provided. Ways are suggested to translate some of the research findings and incorporate family and contextual factors beyond what the individual in the dental chair presents into dental practice.     

Endothelial Activation and Chemoattractant Expression are Early Processes in Isolated Blast Brain Injury

Blast injuries are an increasing problem in military conflicts and terrorist incidents. Blast-induced traumatic brain injury has risen to prominence and represents a specific form of primary brain injury, with sufficiently different physical attributes (and possibly biological consequences) to be classified separately. There is increasing interest in the role of blast in initiating inflammatory responses, which may be linked to the pathological processes seen clinically. Terminally anaesthetised rats were exposed to a blast wave directed at the cranium, using a bench-top blast wave generator. Control animals were not exposed to blast. Animals were killed after 8 h, and the brains examined for evidence of an inflammatory response. Compared to controls, erythropoietin, endothelial integrins, ICAM and sVCAM, and the pro-inflammatory cytokine, monocyte chemoattractant protein-1 (MCP-1) were significantly elevated. Other pro-inflammatory cytokines, including MIP-1α, were also detectable, but levels did not permit accurate quantification. Six inflammatory genes examined by qRT-PCR exhibited a biologically significant increase in activity in the blast-exposed animals. These included genes supporting chemokines responsible for monocyte recruitment, including MCP-1, and chemokines influencing T cell movement. Brain injury is usually accompanied by pathological neuro-inflammation. This study shows that blast brain injury is no exception, and the data provide important mechanistic clues regarding the drivers of such inflammation. Whilst this effect alone is unlikely to be responsible for the totality of consequences of blast brain injury, it suggests a mechanism that may be priming the cerebral inflammatory response and rendering cerebral tissue more susceptible to the deleterious effects of systemic inflammatory reactions.     

Cyclooxygenase-2 dependent and independent antitumor effects induced by celecoxib in urinary bladder cancer cells

Transitional cell carcinoma of the urinary bladder is the second most common genitourinary malignancy in people in the United States. Cyclooxygenase-2 (COX-2) is overexpressed in bladder cancer. COX-2 inhibitors have had antitumor activity against bladder cancer, but the mechanisms of action are unclear. Clinically relevant concentrations of COX-2 inhibitors fail to inhibit proliferation in standard in vitro assays. In pilot experiments, different culture conditions [standard monolayer, modified monolayer, soft agar, collagen, and poly(2-hydroxyethyl methacrylate)-coated plates] were assessed to determine conditions suitable for the study of COX inhibitor growth-inhibitory effects. This was followed by studies of the effects of clinically relevant concentrations of a selective COX-2 inhibitor (celecoxib) on urinary bladder cancer cell lines (HT1376, TCCSUP, and UMUC3). Celecoxib (相似文献   

Cyclooxygenase inhibitors in urinary bladder cancer: in vitro and in vivo effects

More than 14,000 people die from invasive transitional cell carcinoma (TCC) of the urinary bladder yearly in the United States. Cyclooxygenase (COX)-inhibiting drugs are emerging as potential antitumor agents in TCC. The optimal in vitro or in vivo systems to investigate COX inhibitor antitumor effects have not been defined. The purpose of this study was to determine COX-1 and COX-2 expression and antitumor effects of COX inhibitors in human TCC cell lines (HT1376, RT4, and UMUC3 cells) and xenografts derived from those cell lines. COX-2 expression (Western blot, immunocytochemistry) was high in HT1376, modest in RT4, and absent in UMUC3 cells in vitro. Similarly, COX-2 expression was noted in RT4 but not UMUC3 xenografts. COX-2 expression in HT1376 xenografts was slightly lower than that observed in vitro. None of four COX inhibitors evaluated (celecoxib, piroxicam, valeryl salicylate, and NS398) reduced TCC growth in standard in vitro proliferation assays at concentrations that could be safely achieved in vivo (< or =5 micromol/L). Higher celecoxib concentrations (> or =50 micromol/L) inhibited proliferation and induced apoptosis in all three cell lines. Celecoxib or piroxicam treatment in athymic mice significantly delayed progression of HT1376 xenografts, which express COX-2, but not UMUC3 xenografts that lack COX-2 expression. In conclusion, standard in vitro assays were not useful in predicting COX inhibitor antitumor effects observed in vivo. Athymic mice bearing TCC xenografts provide a useful in vivo system for COX inhibitor studies. Results of this study provide justification for further evaluation of COX inhibitors as antitumor agents against TCC.