Computed tomography imaging-based normative orbital measurement in Indian population

Purpose: This study aims to evaluate normal orbital structures with nonenhanced computed tomography (NCCT) and determine normative data for the Indian population. Methods: CT images of the orbits of 100 patients were retrospectively reviewed on a work station to record the normative data of the orbits. Clinical details of all patients were reviewed to ensure that they did not have ocular/orbital diseases. Both axial and coronal images were utilized to record the data. Results: The mean age of the population evaluated was 34.07 years, with male to female ratio of 1.77. The average orbital index for the left orbit was 97 and for the right side was 103. The mean thickness of left inferior rectus, lateral rectus, medial rectus, and the superior rectus was 3.36 mm, 3.14 mm, 3.80 mm, and 3.75 mm, respectively. The right inferior rectus, lateral rectus, medial rectus, and the superior rectus measured 3.46 mm, 3.14 mm, 3.83 mm, and 3.78 mm, respectively. The optic nerve sheath complex diameter varied between 3.05 mm and 7.17 mm for the left eye and 3.05 mm and 7.0 mm for the right eye. Conclusion: The study provides normative data on various orbital structures in an Indian population. This data is likely to be useful for diagnosing various orbital pathologies and in planning surgical orbital procedures.

Attitude toward eye donation - A population-based study from Western Uttar Pradesh

Background: Corneal blindness is one of the major causes of blindness and vision can be successfully restored by corneal transplantation. Eye donation can improve the availability of cornea, but it depends on awareness and willingness in general population. Objectives: The objectives of this study were to assess the awareness and willingness of urban population of western UP about eye donation and to correlate factors with willingness. Materials and Methods: A cross-sectional study was conducted among randomly selected 400 residents >30 years of age of urban field practice area of the Department of Community Medicine, TMMC and RC, Moradabad. Pre-tested structured questionnaire was used to obtain information about the awareness and perception regarding eye donation. Results: Of 400 participants, 75% were aware about eye donation and 25% were ignorant; print and electronic media were the most common source of information. 51.6 % knew about the time limit of eye donation. 63.5% were willing for eye donation; willingness for eye donation was significantly higher in younger age group, males, and well-educated participants. Conclusion: Our study establishes the need to improve the awareness of eye donation in the study population. The most idealist public health approach would be, to reduce the occurrence of vision loss due to corneal diseases, with effective preventive policies, but as a short-term goal, the key way to deal with corneal blindness is to obtain the required number of corneas for transplantation.

Feedback of postgraduate students about research methodology workshop

Background: The feedback from PG students will address the issues in organization of the workshop if any, which may be helpful for the continual improvement. The objectives of the study were to analyze the feedback of postgraduate students about every session of workshop; to analyze the feedback of postgraduate students about overall program of workshop; to assess the change in the knowledge of the participants with the help of pretest and posttest scores.Methods: The present cross sectional study was carried out in the month of August 2018. The three days research methodology workshop was conducted at Shri Vasantrao Naik Government Medical College, Yavatmal during 7th to 9th August 2018 for the 44 postgraduate students. The pretest questionnaire, posttest questionnaire, daily feedback form and program evaluation form were given to each participant. The analysis of pretest and posttest was done by paired t test with statistical software Epi Info Version 7.Results: Total 44 postgraduate students gave feedback on each day. The maximum score (1108) was given by participants to experimental study design and lowest score (942) was given to third group activity based on literature search. For the question about the scope for betterment in the workshop, we had developed three themes based on the responses of participants by using content analysis. Paired ‘t’ test showed significant difference between pre and post-test (p<0.001).Conclusions: The students gave constructive feedback on improvement of the sessions on literature search and Mendeley.

Comparative evaluation of antibacterial property and substantivity of chlorhexidine containing dentifrices with sodium lauryl sulfate and Tween as surfactants: An in vivo study.

Aim: The aim of the study was to determine the antibacterial property and substantivity of chlorhexidine containing dentifrices with sodium lauryl sulfate (SLS) and Tween as surfactants. Materials and Methods: It is a double-blind cross over the study, a total of 20 children within their mixed dentition period (7-13 year) having Streptococci mutans count more than 106 were selected for the main study. Three types of chlorhexidine containing dentifrices were used with a washout period of 1 week. Out of the three toothpastes, one was without surfactant and other two toothpastes contained SLS and Tween as surfactants respectively. 20 volunteers brushed for 1 min during the study day with their assigned toothpaste. Saliva samples were collected before brushing, immediately after brushing and 1, 3, 5, and 7 hand sent for microbial analysis. The culture carried out by inoculating saliva sample onto Mitis salivarius agar for selective isolation of S. mutans followed by counting of colony forming unit. Results: Group I and III (Chlorhexidine and CHX + Tween) had shown statistically significant reduction in bacterial count until 7 h when compared to their baseline values (P < 0.001). Group II toothpaste (CHX + SLS) had shown significant reduction in bacterial count until 3 h only. On inter group comparison, Group III had shown good amount of percentage reduction in bacterial count when compared to other groups. Conclusion: CHX + Tween toothpaste had shown statistically significant reduction in antibacterial activity and substantivity than other groups. These findings show chlorhexidine containing toothpaste with non-ionic surfactant will be able to maintain the antibacterial property and substantivity of chlorhexidine.

Identification of a threshold for biomass exposure index for chronic bronchitis in rural women of Mysore district, Karnataka, India.

Background & objectives: Exposure to air pollution due to combustion of biomass fuels remains one of the significant risk factors for chronic respiratory diseases such as chronic bronchitis. There is a need to identify the minimum threshold level of biomass index that is significantly associated with chronic bronchitis. This study was undertaken to identify a threshold for biomass exposure index in a rural women population in Mysore district, south India. Methods: A cross-sectional survey was conducted in a representative population of Mysore and Nanjangud taluks. Eight villages each from Mysore and Nanjangud were randomly selected based on the list of villages from census 2001. A house-to-house survey was carried out by trained field workers using the Burden of Obstructive Diseases questionnaire, which evaluated the biomass smoke exposure and chronic bronchitis. All the women aged above 30 yr were included in the study. Results: A total of 2011 women from Mysore and 1942 women from Nanjangud participated in the study. All women were non-smoking and used biomass fuels as the primary fuel for cooking. A threshold of biomass fuel exposure of 60 was identified on multivariate analysis in Mysore district after adjusting for age, passive smoking and working in a occupational exposure to dust, as the minimum required for a significant association with chronic bronchitis. One in every 20 women in Mysore district exposed to biomass fuel exposure index of 110 or more developed chronic bronchitis. Interpretation & conclusions: The minimum threshold of biomass exposure index of 60 is necessary to have a significant risk of developing chronic bronchitis in women. The number needed to harm to develop chronic bronchitis reduces with increasing biomass exposure index and women residing in rural Nanjangud have a higher risk for developing chronic bronchitis as compared to women in Mysore.

Factors affecting 30-month survival in lung cancer patients.

Background & objectives: Age adjusted incidence rate of lung cancer in India ranges from 7.4 to 13.1 per 100,000 among males and 3.9 to 5.8 per 100,000 among females. The factors affecting survival in lung cancer patients in India are not fully understood. The current study was undertaken to evaluate the factors affecting survival in patients diagnosed with lung cancer attending a tertiary care cancer institute in Bangalore, Karnataka, India. Methods: Consecutive patients with primary lung cancer attending Bangalore Institute of Oncology, a tertiary care centre at Bangalore, between 2006 and 2009 were included. Demographic, clinical, radiological data were collected retrospectively from the medical records. Results: A total of 170 consecutive subjects (128 males, 42 females) diagnosed to have lung cancer; 151 non-small cell lung cancer (NSCLC) and 19 small cell lung cancer (SCLC) were included. A higher proportion of never-smokers (54.1%) were observed, mostly presenting below the age of 60 yr. Most subjects were in stage IV and III at the time of diagnosis. More than 50 per cent of patients presented with late stage lung cancer even though the duration of symptoms is less than 2 months. The 30-month overall survival rates for smokers and never-smokers were 32 and 49 per cent, respectively. No significant differences were observed in 30 month survival based on age at presentation, gender and type of lung cancer. Cox proportional hazards model identified never-smokers and duration of symptoms less than 1 month as factors adversely affecting survival. Interpretation & conclusions: Our results showed that lung cancer in Indians involved younger subjects and associated with poorer survival as compared to other ethnic population. Studies on large sample need to be done to evaluate risk factors in lung cancer patients.

Prevalence of chronic cough, chronic phlegm & associated factors in Mysore, Karnataka, India.

Background & objectives: Chronic cough and chronic phlegm are important indicators of respiratory morbidity, accelerated lung function decline, increased hospitalization and mortality. This study was planned to estimate the prevalence of chronic cough and phlegm in the absence of dyspneoa and wheezing and to study its associated factors in a representative population of Mysore district. Methods: A cross-sectional survey was planned in a representative population of Mysore taluk. Eight villages were randomly selected based on the list of villages from census 2001. Trained field workers using the Burden of Obstructive Diseases questionnaire carried out a house-to-house survey. Results: A total of 4333 adult subjects were enrolled in the study with 2333 males and 2000 females. The prevalence of chronic cough in the community was 2.5 per cent and that of chronic phlegm was 1.2 per cent. A significant association was observed between chronic cough and age, gender, occupation and smoking and chronic phlegm with age, gender, occupation, indoor animals and smoking. A multivariate analysis confirmed independent association of age, occupation and smoking for chronic cough and age and smoking for chronic phlegm. On sub-group analysis of males, heavy smokers had higher prevalence of chronic cough and chronic phlegm as compared to light smokers and non smokers. Interpretation & conclusions: The prevalence of chronic cough was 2.5 per cent and chronic phlegm was 1.2 per cent in the general population in Mysore which is lower than that observed in other studies. Heavy smoking was an important preventable risk factor identified in this study and efforts towards smoking cessation are crucial to achieve good respiratory health in the community.

Prevalence of Prediabetes in School-Going Children.

school children in Mysore city. Design: Cross sectional study. Settings: Children aged 5-10 years from three schools in Mysore city were included. Study was done over a period of 1 year during 2006-2007. Participants: 726 children (59.8% males). Main Outcome: Prevalence of prediabetes. Prediabetes was defined as fasting blood sugar level between 100-125 mg/dL. Results: The prevalence of prediabetes was 3.7%. No statistically significant association was observed with major risk factors of diabetes. Conclusions: Efforts must be made to recognize type 2 diabetes in the asymptomatic prediabetes state.

Reattachment Of Embedded Tooth Fragment: A Case Report.

Soft tissue injuries are relatively common following traumatic dental injuries in children. This report describes a case of a nine year old girl who had a foreign body embedded in the lower lip due to fall, while playing. Thorough clinical examination followed by soft tissue radiographs confirmed the presence of a fractured incisal fragment, which was surgically retrieved under local anesthesia. The fragment was then reattached using a dentin bonding agent. Fragment reattachment is a realistic alternative to resin composite buildup for restoring esthetics and function of the traumatized dentition. The natural fragments can be used to ensure the restoration “ad integrum” of the dental crown by simple bonding. With expected improved bonding technology in the future, these fragments may serve for many years.

Factors associated with non-adherence to specific allergen immunotherapy in management of respiratory allergy.

Background. Non-adherence to specific allergen immunotherapy is a major hurdle faced by the allergist, contributing to poor clinical outcomes. Objectives. To assess the independent association of various factors with non-adherence to specific allergen immunotherapy. Methods. Fifty consecutive (non-adherent) and control (adherent) subjects receiving specific allergen immunotherapy were included in the study and various factors related to non-adherence including socio-demographic, clinical and immunotherapy related variables were compared between the two groups by univariate and multivariate analysis. Results. On univariate analysis, gender, allergic conjunctivitis, family history, progression of disease, perception of immunotherapy, medicine requirement, and the pattern of missed doses greater than two in the last 10, 20 and 30 doses were found to be significantly associated with non-adherence. On multivariate analysis, independent association was observed with allergic conjunctivitis, family history, perception of immunotherapy, missed doses greater than two in the last 10 doses of immunotherapy and medicine requirement. Conclusions. The independent factors associated with non-adherence may vary between different settings and countries. There is a need for developing individual case holding programmes to improve clinical outcomes in patients receiving specific allergen immunotherapy.

Antibacterial effect of bioactive glass in combination with powdered enamel and dentin.

Background and Objectives: In endodontics, various intracanal medications have been advocated to eliminate bacteria after root canal instrumentation. A recent study has revealed that addition of powdered dentin to bioactive glass (BAG) led to increased glass dissolution, and an increased antibacterial efficacy. Therefore, the present study was undertaken to compare the effect of enamel and dentin powder on the antibacterial efficacy of a commercially available BAG. Materials and Methods: Dentin blocks (dbs) were prepared from single rooted human teeth. These dbs were infected with Enterococcus faecalis for two weeks in Tryptic Soy Broth (TSB), while negative controls were kept in sterile TSB. In group I, the infected dbs were filled with BAG, in group II with BAG + Enamel powder and group III with BAG + Dentin powder. Dentin samples were harvested from the dbs and cultured. Statistical Analysis: Kruskal-Wallis ANOVA was used for multiple group comparison followed by Scheffe's post hoc test for pair-wise comparisons. Results: All the combinations of BAG evaluated significantly reduced the bacterial counts compared to the control group. However, at the end of 24 hours, three days, and five days BAG + Dentin powder showed significant reduction ( P < 0.01) in bacterial counts compared to the other experimental groups. Conclusion: Among the various materials evaluated, it appeared that though BAG exhibits antimicrobial efficacy, the addition of powdered enamel and dentin in aqueous suspension definitely enhanced this property. However, the addition of enamel powder BAG did not significantly alter its antimicrobial efficacy compared to BAG + dentin powder.

Effect of curry leaves, garlic and tea tree oil on Streptococcus mutans and Lactobacilli in children: a clinical and microbiological study / Efeito de folhas de curry, alho e óleo de malaleuca sobre Streptococcus mutans e Lactobacilli em crianças: um estudo clínico e microbiológico

Objective: To evaluate and compare the anti microbial efficacy of Curry leaves, Garlic and Tea tree oil mouthwashes against Streptococcus mutans and Lactobacillus. Method: The study was carried out for 14 days. Thirty six children were selected and randomly divided into four groups: group I (subjected to placebo mouthwash), Group II (subjected to 2.5% curry leaves mouthwash), group III (subjected to 2.5% garlic mouthwash), roup IV (subjected to 0.2% tea tree oil mouthwash). Baseline samples ('0' day) were collected on the 1st day morning after brushing. After half an hour, all groups were subjected to 10 ml of mouthwash rinse for one minute as divided group wise followed by the collection of salivary sample designated as '1/2 hr' sample. Daily twice rinsing of mouthwashes was carried out for 7 days as per group respectively. The rest of salivary samples were collected on 3rd day and 7th day morning. Aft er 7th day, the regimen was discontinued and saliva sample was collected on the 14th day to observe the substantivity. Dishes containing Mitis Salivarius Bacitracin agar (MSB) and Rogassa L agar were inoculated with the subject?s saliva followed by colony counting respectively. Results: Curry leaves, Garlic and Tea tree oil showed significant anti microbial activity against streptococcus mutans and lactobacilli. Significant maintenance of reduced levels of microorganisms was observed only for garlic and tea tree oil on the 14th day. Unpleasant taste (curry leaves 44.4%, garlic 88.9%, tea tree oil 66.6%), burning sensation (curry leaves 55.6%, garlic 88.9% , tea tree oil 77.8%,), bad breath (curry leaves 44.4%, garlic 100% , tea tree oil 22.2%,), and nausea (curry leaves 0%, garlic 100% , tea tree oil 44.4%,) were reported. Conclusion: Tea tree oil, Garlic and Curry leaves mouthwashes are effective against cariogenic bacteria and might be an easily accessible and cheaper alternative to allopathic mouthwashes.

Objetivo: Avaliar e comparar a eficácia anti bacteriana de folhas de curry, alho e óleo de malaleuca sobre Streptococcus mutans e Lactobacilli. Método: O estudo teve duração de 14 dias. Trinta e seis crianças foram selecionadas e divididas aleatoriamente em quatro grupos: Grupo I (solução de bochecho placebo), Grupo II (solução de bochecho de folhas de curry a 2,5%), Grupo III (solução de bochecho de alho a 2,5%), Grupo IV (solução de bochecho de óleo de malaleuca a 0,2%). As amostras iniciais de saliva (dia '0) foram coletadas na manhã do 1º dia após a escovação dos dentes. Após meia hora, todos os grupos utilizaram 10 ml de solução de bochecho por 1 minuto, seguindo-se da coleta de amostra de saliva designada como amostra '1/2 hora'. O uso da respectiva solução de bochecho duas vezes ao dia segui-se por 7 dias em cada grupo. As demais amostras de saliva foram coletadas na manhã do 3º e do 7º dia. Após o 7º dia, o regime foi interrompido e amostras de saliva foram coletadas no 14º dia a fim de analisar a substantividade de cada solução. Placas contendo agar Miti s Salivarius Bacitracin (MSB) e ágar Rogassa L foram inoculadas com as amostras de saliva dos sujeitos seguindo-se de contagem do número de colônias. Resultados: Folhas de curry, alho e óleo de malaleuca apresentaram significativa atividade anti microbiana sobre streptococcus mutans e lactobacilli. Signifi cativa manutenção de níveis reduzidos de microorganismos foi observada somente para o alho e óleo de malaleuca no 14º dia. Gosto desagradável foi reportado (folhas de curry: 44,4%, alho: 88,9%, óleo de malaleuca: 66,6%), sensação de queimação (folhas de curry: 55,6%, alho: 88,9%, óleo de malaleuca: 77,8%), halitose (folhas de curry: 44,4%, alho: 100%, óleo de malaleuca: 22,2%,), e náusea (folhas de curry: 0%, alho: 100%, óleo de malaleuca: 44,4%).

Conclusão: Soluções de bochecho a base de folhas de curry, alho e óleo de malaleuca mostraram-se eficiente contra bactérias cariogênicas e podem ser uma alternativa facilmente acessível e mais baratas às soluções de bochecho alopáticas.

Effect of surface treatment with remineralizing on the color stability and roughness of esthetic restorative materials / Efeito do tratamento de superfície na estabilidade de cor e aspereza em materiais restauradores estéticos

OBJECTIVES: The purpose of the study was to evaluate and compare the in vitro effect of fluoride varnish, APF gel and MI paste on the color stability and surface roughness of esthetic restorative materials. MATERIAL AND METHODS: 60 disks of each conventional glass ionomer and resin composite were made using molds of 1.2 cm x 2 mm. All the specimens were suspended in artificial saliva for 48 hours at 37ºC. Subsequently, fluoride varnish, APF gel, and MI paste were applied to all the subgroups except the controls. All the specimens were again suspended in artificial saliva and incubated at 37ºC for 24 hours. After incubation, they were cleaned using a toothbrush and toothpaste, and stored in the artificial saliva for 1 week. During this period, the specimens were subjected to color and surface roughness measurement. RESULTS: Measurements were expressed as mean ± standard deviation and compared between two groups by Student’s t test. One way ANOVA was used for multiple group comparison and Tukey’s test for pair wise comparison. CONCLUSION: The deterioration of GIC material was more rapid compared to composites when fluoride varnish, APF gels and GC Tooth Mousse were applied. The use of remineralizing agents on esthetic restorative materials causes changes in color and surface texture.

OBJETIVOS: A finalidade deste estudo foi avaliar e comparar o efeito in vitro do verniz com flúor, do gel APF e da pasta MI na estabilidade de cor e aspereza de superfícies de materiais restauradores estéticos. MATERIAL E MÉTODO: 60 discos de cimento de ionômero de vidro convencional e 60 de resina composta foram produzidos usando moldes de 1,2 cm x 2 mm. Todos os corpos de prova foram mantidos em saliva artificial por 48 horas a 37oC. Em seguida, verniz fluorado, gel APF e pasta MI foram aplicados a todos os subgrupos, com exceção do grupo controle. Todos os corpos de prova foram novamente imergidos em saliva artificial e incubados a 37oC por 24 horas. Após a incubação, eles foram limpos utilizando escova de dentes e pasta, sendo mantidos em saliva artificial por uma semana. Durante esse período, os corpos foram submetidos a medições de coloração e de aspereza de superfície. RESULTADOS: As medidas foram expressas como medianas +- de desvio-padrão e comparadas entre dois grupos pelo teste t de Student. ANOVA foi usada para comparação entre grupos e o teste de Tukey foi utilizado para comparações por pares. CONCLUSÃO: A deterioração do ionômero de vidro foi mais rápida quando comparada com os compósitos pela aplicação de verniz com flúor, gel APF e pasta GC dental. O uso de agentes remineralizantes nas restaurações estéticas pode causar alterações de cor e textura de superfície.

Avaliação comparativa do Carisolv na remoção da dentina cariada em molares decíduos: estudo in vitro / Comparative evaluation of Carisolv in removal of carious dentin in primary molar teeth: in vitro study

Objetivo: Avaliar e comparar a eficiência e efetividade do Carisolv na remoção de tecido cariado em molares decíduos. Método: Trinta molares decíduos cariados foram seccionados mésio-distalmente e obtidos 60 espécimes. O Carisolv foi utilizado para remoção do tecido cariado nas 30 seções as quais foram denominadas de Grupo Experimental (GE) e nas 30 seções restantes executou-se a remoção convencional, sendo denominado de Grupo Controle (GC). O tempo gasto para a remoção foi registrado (em minutos) e comparado entre os grupos. Todas as amostras foram analisadas quanto à quantidade de dentina desminaralizada remanescente sob estereomicroscópio. O valores foram registrados em microns. A quantidade de tecido cariado remanescente foi verificada por meio da aplicação de corantes detectores de cárie. Em seguida, a dureza da dentina remanescente foi analisada através da dureza Vicker's, sendo realizada a comparação entre os grupos através do uso do Teste T de Student. Resultados: Verificou-se que os valores médios para a remoção da dentina cariada mostraram-se estatisticamente significante e maiores para o Carisolv (GE) quando comparado à remoção convencional (GC). Ademais, observou-se que a remoção com o Carisolv deixa muito mais quantidade de dentina desmineralizada e a camada de dentina apresenta menor dureza quando comparada à remoção convencional. Conclusão: Carisolv mostrou-se menos efetivo e eficiente quando comparado à remoção de tecido cariado convencional que demanda maior tempo para remoção do tecido cariado. Além do mais, a remoção com Carisolv deixa maior quantidade de dentina desmineralizada, a qual possui menor dureza do que as amostras obtidas com a remoção convencional.

Effect of glutaraldehyde and ferric sulfate on shear bond strength of adhesives to primary dentin.

AIM: The present study was undertaken to evaluate the effect of alternative pulpotomy agents such as glutaraldehyde and ferric sulfate on the shear bond strength of self-etch adhesive systems to dentin of primary teeth. MATERIALS AND METHODS: Eighty human primary molar teeth were sectioned in a mesiodistal direction and divided into experimental and control groups. Lingual dentin specimens in experimental groups were treated with glutaraldehyde and ferric sulfate. Buccal surfaces soaked in water served as control group. Each group was then divided into two groups based on the adhesive system used: Clearfil SE Bond and Adper Prompt L-Pop. A teflon mold was used to build the composite (Filtek Z-250) cylinders on the dentinal surface of all the specimens. Shear bond strength was tested for all the specimens with an Instron Universal Testing Machine. The failure mode analysis was performed with a Scanning Electron Microscope (SEM). RESULTS: The results revealed that glutaraldehyde and ferric sulfate significantly reduced the shear bond strength of the tested adhesive systems to primary dentin. Clearfil SE Bond showed much higher shear bond strength than Adper Prompt L Pop to primary dentin. SEM analysis revealed a predominant cohesive failure mode for both adhesive systems. CONCLUSION: This study revealed that the pulpotomy medicaments glutaraldehyde and ferric sulfate adversely affected the bonding of self-etch adhesive systems to primary dentin.

The effect of water purification systems on fluoride content of drinking water.

OBJECTIVE: The purpose of the present study was to determine the effect of different water purification systems on the fluoride content of drinking water and to compare the efficacy of these water purification systems in reducing the fluoride content. MATERIALS AND METHODS: Five different water purification systems were tested in this study. They were reverse osmosis, distillation, activated carbon, Reviva , and candle filter. The water samples in the study were of two types, viz, borewell water and tap water, these being commonly used by the people of Davangere City, Karnataka. The samples were collected before and after purification, and fluoride analysis was done using fluoride ion-specific electrode. RESULTS: The results showed that the systems based on reverse osmosis, viz, reverse osmosis system and Reviva showed maximum reduction in fluoride levels, the former proving to be more effective than the latter; followed by distillation and the activated carbon system, with the least reduction being brought about by candle filter. The amount of fluoride removed by the purification system varied between the system and from one source of water to the other. INTERPRETATION AND CONCLUSION: Considering the beneficial effects of fluoride on caries prevention; when drinking water is subjected to water purification systems that reduce fluoride significantly below the optimal level, fluoride supplementation may be necessary. The efficacy of systems based on reverse osmosis in reducing the fluoride content of water indicates their potential for use as defluoridation devices.

Sealing ability and thermal diffusivity of cavity lining materials: an in vitro study.

AIMS: The purpose of this study was to evaluate and compare the sealing ability and the thermal insulating capability of four different cavity lining materials. MATERIALS AND METHODS: Forty noncarious human mandibular second premolars that were extracted for orthodontic treatment were collected, cleaned, and stored in distilled water. These premolars were randomly divided into four groups of ten teeth each for treatment with the different cavity lining materials. Group I teeth were treated with cavity varnish, group II teeth with amorphous calcium phosphate (ACP), group III teeth with dentin bonding agent, and group IV teeth with resin-modified glass ionomer cement (RMGIC). Electrical resistance and the difference in the time-temperature curve of the external surface and the pulp side [A D -A P ] of each tooth following heat and cold application for 120 s were measured before and after cavity lining placement to determine the sealing ability and thermal insulating property, respectively. Data collected were subjected to statistical analysis. For paired data, paired t-test and Wilcoxon's signed rank test were used. One-way ANOVA was used for comparisons between multiple groups and the Mann-Whitney U test for comparisons between pairs. RESULTS: The mean difference in electrical resistance (in K ohm) of different cavity lining materials were as follows: group I = +3.53, group II = -1.00, group III = +20.43, and group IV = +11.44. The mean differences in the area (A D -A P ) under the time-temperature curve following heat application were as follows: group I = 6.6 mm 2 , group II = 15.3 mm 2 , group III = 130.5 mm 2 , and group IV = 412.0 mm 2 . The mean differences in the area (A D -A P ) under the time-temperature curve following cold application were as follows: group I = 24.5 mm 2 , group II = 3.2 mm 2 , group III = 314.9 mm 2 , and group IV = 480.5 mm 2 . CONCLUSION: Dentin bonding agent and RMGIC provided effective sealing of the dentinal tubules and significant thermal insulation when compared to the other tested cavity lining materials.

A comparison between audio and audiovisual distraction techniques in managing anxious pediatric dental patients.

Pain is not the sole reason for fear of dentistry. Anxiety or the fear of unknown during dental treatment is a major factor and it has been the major concern for dentists for a long time. Therefore, the main aim of this study was to evaluate and compare the two distraction techniques, viz, audio distraction and audiovisual distraction, in management of anxious pediatric dental patients. Sixty children aged between 4-8 years were divided into three groups. Each child had four dental visits--screening visit, prophylaxis visit, cavity preparation and restoration visit, and extraction visit. Child's anxiety level in each visit was assessed using a combination of four measures: Venham's picture test, Venham's rating of clinical anxiety, pulse rate, and oxygen saturation. The values obtained were tabulated and subjected to statistical analysis. It was concluded that audiovisual distraction technique was more effective in managing anxious pediatric dental patient as compared to audio distraction technique.

A comparison of impact strength of fragment-bonded anterior teeth using three different restorative materials: an in vitro study.

BACKGROUND AND OBJECTIVE: The purpose of this investigation was to estimate the impact strength of fractured anterior teeth reattached using three different restorative materials and compare their impact strengths to those of control. MATERIALS AND METHODS: Sixty human maxillary permanent central incisors were selected and divided into control and experimental groups. The teeth in the experimental groups were fractured and then bonded using Composite resin, Compomer and resin-modified GIC. Intact teeth served as control. All the specimens were then tested in an impact testing machine. RESULTS: The results revealed statistically significant differences between Compomer and resin-modified GIC groups, control and experimental groups. No statistically significant differences were observed between Composite resin and Compomer groups. CONCLUSION: Thus the fractured fragments bonded with Composite resin and Compomer provided better adhesion than resin-modified GIC.

A comparative evaluation of four restorative materials to support undermined occlusal enamel of permanent teeth.

The purpose of this study was to test the support to undermined occlusal enamel provided by posterior restorative composite (FiltekTM P60, 3M Dental products USA), polyacid modified resin composite (F2000 compomer, 3M Dental products, USA.), radiopaque silver alloy-glass ionomer cement (Miracle Mix. GC Corp, Tokyo, Japan) and Glass Ionomer cement (Fuji IX GP). To test each material, 20 human permanent mandibular third molars were selected. The lingual cusps were removed and the dentin supporting the facial cusps was cut away, leaving a shell of enamel. Each group of prepared teeth was restored using the materials according to the manufacturer's instructions. All the specimens were thermocycled (250 cycles, 6 degrees C- 60 degrees C, dwell time 30 seconds) and then mounted on an acrylic base. Specimens were loaded evenly across the cusp tips at a crosshead speed of 5 mm /minute in Hounsfield universal testing machine until fracture occurred. Data obtained was analyzed using analysis of variance and Studentized- Newman- Keul's range test. No significant differences were detected in the support provided by P-60, F 2000, Miracle Mix or Fuji IX GP groups. The support provided to undermined occlusal enamel by these materials was intermediate between no support and that provided by sound dentin. Without further development in dental material technology and evidence of its efficacy, restorative materials should not be relied upon to support undermined occlusal enamel to a level comparable to that provided by sound dentin.