MATERIALS AND METHODS: Sixty human premolar teeth were selected and were randomly grouped, with 20 specimens in each group: group 1 - fluoride releasing dentin bonding agent; group 2 - antibacterial containing dentin bonding agent; and group 3 - one step conventional self etch adhesive. Each group was treated with its respective bonding agents, composite resin build up was done, and shear bond strengths were tested using Instron Universal testing machine. Few of the specimens were tested under SEM.
RESULTS: The results were statistically analysed using One-way ANOVA and paired t-test. It was observed that group 3 has the highest shear bond strength followed by group 2, and then group 1. Adhesive failures and mixed failures were most frequent types of failures as seen under SEM.
CONCLUSION: Addition of antimicrobial agent decreases the bond strength of dentin bonding agent and addition of fluoride further decreases the bond strength. From SEM results it can be concluded that the zone of failure could not be defined and also that the failure mode was independent of the dentin bonding agent used.
METHODS: Children having home overnight oximetry for suspected OSA were identified over 12 months, and those with a normal result who went on to have polysomnography (PSG) were included. Oximetry, including PR-SD and PRI (rises of 8, 10 and 15 beats/min per hour), was analyzed using commercially available software. PR parameters were compared between those with OSA (obstructive apnoea-hypopnoea index (OAHI) >1 event/h) and those without OSA.
RESULTS: One hundred sixteen children had normal oximetry, of whom 93 (median age 4.5 years; 55 % M) had PSG. Fifty-seven of 93 (61 %) children had OSA (median OAHI 4.5 events/h, range 1.1-24). PR-SD was not different between the OSA and non-OSA groups (p = 0.87). PRI tended to be higher in those with OSA, but there was considerable overlap between the groups: PRI-8 (mean ± SD 58.5 ± 29.0/h in OSA group vs 48.6 ± 20.2/h in non-OSA group, p = 0.07), PRI-10 (45.1 ± 25.0 vs 36.2 ± 16.7, p = 0.06) and PRI-15 (24.4 ± 14.5 vs 18.9 ± 9.0, p = 0.04). A PRI-15 threshold of >35/h had specificity of 97 % for OSA.
CONCLUSION: The PRI-15 shows promise as an indicator of OSA in children with normal oximetry.