Materials and methods Enhance-L.C. was used with one of the manufacturer's recommended adhesives, Light-Bond, and with a second from another manufacturer, Transbond-XT. One hundred premolars were divided into four groups of 25 premolars: 1)Transbond-XT, 2) Transbond-XT/Enhance-L.C., 3) Light-Bond, 4) Light-Bond/Enhance-L.C. Main outcome measures Shear bond strength was evaluated with a universal test machine and the adhesive remaining after debonding was determined using image analysis equipment. Results Enhance-L.C. did not significantly increase the bond strength of either of the two systems (P > 0.008). However, LightBond/Enhance-L.C. provided a bond strength significantly greater (P < 0.008) than Transbond-XT and Transbond-XT/Enhance-L.C. Light-Bond also left significantly (P < 0.05) less adhesive remaining on the enamel than Transbond-XT, whether or not either of the systems were used with Enhance-L.C. Conclusions The use of Enhance-L.C with Light-Bond is to be recommended whenever extra bond strength is needed.Bracket bond failure is one of the most frustrating ocurrences in orthodontic practice. The consequences include an increase in treatment time, additional costs in both materials and personnel, and additional patient visits.

This study evaluated the effect of the topical application of melatonin in accelerating bone formation associated with implants 2 months after their application to the tibiae of rabbits. Twenty New Zealand rabbits were used. Twenty implants treated with melatonin and 20 control implants without melatonin were placed in the proximal metaphyseal area of each tibia. Studies of new bone formation were subsequently made at 15, 30, 45 and 60 days. Cortical width and cortical length of new bone formation were measured. Following implantation, an anteroposterior and lateral radiologic study was carried out. Collected samples were sectioned at 5 μm and stained using hematoxylin-eosin, Masson's trichromic and Gordon-Switt reticulin stains. After a 60 day treatment period, melatonin increased the length of cortical bone (95.13±0.42%) versus that around control implants (62.91±1.45%). Related to the perimeter of cortical bone of the tibiae, melatonin induced new bone 88.35±1.56% versus 60.20±1.67% in the control implants. Melatonin regenerated the width and length of cortical bone around implants in tibiae of rabbits more quickly than around control implants without the addition of melatonin.

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The purpose of this study was to evaluate the effects of Coca-Cola and Schweppes Limón on bond strength, adhesive remnant, and microleakage beneath brackets. One hundred and twenty upper central incisor brackets were bonded to bovine incisors and divided into three groups: (1) Control, (2) Coca-Cola, and (3) Schweppes Limón. The teeth were submerged in the drinks three times a day for 15 minutes over a 15 day period. Shear bond strength (SBS) was measured with a universal testing machine, and adhesive remnant evaluated using image analysis equipment. Microleakage at the enamel-adhesive and adhesive-bracket interfaces was determined using methylene blue. One hundred and eight teeth were used for scanning electron microscopy to determine the effect of the drinks on intact and sealed enamel. SBS and adhesive remnant data were analysed using the Kruskal-Wallis test (P < 0.05) and microleakage using the Kruskal-Wallis and Mann-Whitney tests applying Bonferroni correction (P < 0.017). No significant differences were found in SBS and adhesive remnant between the groups (P > 0.05). Microleakage at the enamel-adhesive interface for groups 2 and 3 was significantly greater than for group 1 (P < 0.017). At the adhesive-bracket interface, microleakage was significantly greater in group 2 than in group 1 (P < 0.017) while microleakage in group 3 did not differ significantly from either group 1 or 2 (P < 0.017). The drinks produced enamel erosion, loss of adhesive and microleakage. Coca-Cola and Schweppes Limón did not affect the SBS of brackets or the adhesive remnant.