Chemomechanical versus drilling methods for caries removal: an in vitro study

The purpose of this study was to compare the performance of chemomechanical caries removal (CMCR) with that of conventional drilling for efficacy of caries removal, time spent, morphological changes and microhardness of surface dentin, and microleakage of subsequent restorations. Forty-six carious deciduous molars were randomly divided into two groups: one each for caries removal by (1) CMCR and by (2) drilling. The completeness of caries removal was evaluated by visual and tactile criteria and a caries detector device. Twenty teeth in each group were restored with glass ionomer (GI) and subjected to thermocycling before undergoing microleakage and microhardness tests. In each group, three restored teeth were used for polarized light microscopic analysis, and three unrestored teeth for scanning electron microscopy (SEM). There was no significant difference in the completeness of caries removal between groups. However, time spent for caries removal by CMCR was significantly longer than that required for drilling. Restorations in the CMCR group had significantly more microleakage than those in the drilling group. Dentin hardness of the cavity floor after CMCR was also significantly lower. Microscopic analyses showed roughened and irregular dentin surfaces in the CMCR group, unlike the smooth surfaces observed in the drilling group. In conclusion, CMCR was as efficacious as drilling in term of completeness of caries removal, but required longer excavation times and resulted in lower microhardness of residual dentin as well as more microleakage after restorations with GI. Further laboratory and clinical evaluations on the efficiency and performance of CMCR for the durability of subsequent restorations are required.

Increased risk of preterm birth among non- smoking, non- alcohol drinking women with maternal periodontitis.

The aim of this case-control study was to examine the association between periodontitis and preterm birth among non-smoking, non-alcohol drinking women. The cases were 130 women who delivered a live singleton newborn before 37 weeks gestation. A random sample of 260 women who delivered a normal child on the same day as the cases were selected as controls. Periodontal examinations were performed during 24-hour period postpartum at bedside. Other related information was collected by structured questionnaire and medical records. Multiple logistic regression analysis was performed controlling for age, ethnicity, place of residence, education, occupation, income, pre-pregnancy body mass index (BMI), weight gain, antenatal care (ANC), parity, systematic infections, genitourinary infections, antibiotics used, and history of periodontal treatment. Periodontitis (defined as presence of at least 4 teeth having > or = 1 site with a probing depth (PD) > or = 4 mm, clinical attachment loss (CAL) > or = 3 mm and bleeding on probing (BOP) after 10 seconds at the same site) was diagnosed in 33.9% of cases and 10.4% of controls. Periodontitis was significantly associated with preterm birth (adjusted OR = 4.47, 95%Cl= 2.43, 8.20). These findings suggest that periodontitis may increase the risk of preterm delivery even among women who do not smoke or drink.