Effects of different application durations of ER:YAG laser on intrapulpal temperature change during debonding.

This study was done to determine the amount of lasing time required to remove ceramic brackets safely without causing intrapulpal damage by using Er:YAG laser with the scanning method. Part 1: 80 bovine mandibular incisors with ceramic brackets were randomly assigned into four groups of 20 as one control and three study groups. In the study groups, brackets were debonded after lasing for 3, 6, and 9 s, whereas debonding was performed without lasing in the control group. Shear bond strengths and ARI scores were also measured. Part 2: 30 human premolars with ceramic brackets were randomly divided into three groups of ten, as 3, 6, and 9 s of lasing durations. Intrapulpal temperature was measured at the same lasing times by a thermocouple. Statistically significant lower shear bond strengths were found in study groups compared to the control. A negative correlation was seen between the bond strengths and ARI scores in such a way that, as the shear bond strengths decreased, the ARI scores increased. Temperature increases for all the study groups were measured below the 5.5°C benchmark. All lasing times were effective for debonding without causing enamel tear outs or bracket failures. The temperature proportionally increased with the extension of the lasing duration. Six-second lasing by the scanning method using Er:YAG laser was found to be the most effective and safest way of removing the ceramic brackets without causing damage to the enamel and pulpal tissues.

Plant extract ankaferd blood stopper effect on bond strength.

OBJECTIVE: To determine the effect of Ankaferd Blood Stopper (ABS) on the shear bond strength (SBS) of orthodontic attachments. MATERIALS AND METHODS: The study material consisted of 60 freshly extracted bovine permanent mandibular incisor teeth. All teeth were cleaned and randomly divided into three groups of 20 specimens and etched with 37% phosphoric acid for 15 seconds, washed, and air-dried. Teeth in groups 1 and 2 were contaminated with ABS and blood, respectively. Teeth in group 3 were only air-dried. Roth Generous maxillary central incisor brackets were bonded with Transbond XT to all teeth. SBS was applied using a universal test machine. The one-way analysis of variance (ANOVA) test was used to determine significant differences in SBS between the three groups, and Tukey honestly significant post hoc test was used to compare subgroups. RESULTS: The mean bond strengths and standard deviations of groups 1, 2, and 3 were 9.58 +/- 0.95, 4.04 +/- 0.69, and 19.56 +/- 1.84 MPa, respectively. CONCLUSIONS: Specimens contaminated with blood showed a statistically significant lower in vitro SBS than those contaminated with ABS. ABS may be used clinically for obtaining a blood-free tooth surface during application of the brackets on surgically exposed, impacted teeth.

Perception of pain and discomfort during tooth separation.

OBJECTIVES: To evaluate patients' perceptions of pain and discomfort during tooth separation and to compare the effectiveness of brass wire and elastomeric separators. METHODS: The participants were 87 adults with a mean age of 22.1 +/- 1.9 years. Elastomeric and brass wire separators were inserted mesial and distal to upper right (elastomeric separators) and upper left first molars (brass wire separators) in each subject. After seven days, the amount of tooth separation was measured with a leaf gauge, and pain perception and discomfort were evaluated with a visual analogue scale and questionnaire. RESULTS: The elastomeric separators produced significantly more separation than the wire separators. There was a statistically significant difference in the subjects' perceptions of pain and discomfort at rest and during chewing between the different separators (p < 0.001). In general, the brass wire separators caused the greatest pain and discomfort immediately after insertion. Pain from the wire separators subsided over seven days, whereas elastomeric separators caused the greatest pain on the first two days after insertion. Eating was negatively influenced by the separation in 61 per cent of the subjects on the first day. On the other hand, other daily activities were affected minimally. CONCLUSIONS: The different levels of pain and discomfort caused by these separators, together with their advantages and disadvantages, can help the clinician to choose an appropriate separator. Patients should be warned that pain due to separation may affect their chewing, social life, school work and sleeping. Analgesics and soft food are recommended following placement of separators.