فهرست مطالب marzie kachuie

Tooth bleaching sensitivity (TBS) after bleaching procedures is a common problem. This study was undertaken to determine the effect of preoperative systemic capsaicin on tooth sensitivity (TS) after in‑office bleaching procedures.

Thirty participants received the treatment in this clinical trial. The subjects were randomly assigned to two groups (n = 15). Placebo and 0.25% capsaicin were administered three times daily for 24 h,with the first dose being administrated 1 h before the bleaching procedure. The subjects underwent two bleaching sessions at a 2‑week interval by applying 40% hydrogen peroxide gel on six upper anterior teeth. A visual analog scale (VAS) was used to evaluate TS. Data were analyzed with SPSS 24. Statistical analyses were carried out with the Wilcoxon test and paired t‑test. Statistical significance was set at P ≤ 0.05.

In the capsaicin group, there was a significant increase in TBS between the immediate and 1‑h postoperative intervals and a significant decrease between 1‑ and 24‑h postoperative intervals (P = 0.01 and P = 0.000,respectively).In the placebo group,there was a significant decrease between immediate and 24‑h and between 1‑ and 24‑h postoperative intervals (P = 0.007, P = 0.02). Milder TS was detected in the placebo group 24 h after bleaching (P < 0.05).

Under the limitations of this study, preoperative use of systemic capsaicin did not significantly affect TS after the in‑office bleaching procedure.

Dentists often face challenges in maintaining adequate oral hygiene for orthodontic patients. Nowadays, there are many oral health applications available that, along with interactive education and reminders, ultimately lead to better oral hygiene and desired oral health. This study aimed to investigate the level of use of these applications by orthodontic professionals in our country.

Methods & Materials: 

The present study was a descriptive cross-sectional questionnaire-based study, conducted in 2022. Using a convenient sampling method, 188 orthodontic professionals were recruited from the country, and 101 of them completed the questionnaire with informed and voluntary consent. A questionnaire was designed and validated to determine the familiarity and use of education and reminder health applications by professionals, and the data were collected online. Descriptive statistics were used to report the results, and the relationship between variables was analyzed using the chi-square test at a confidence level of 95%.

Most of the specialists had some difficulty with maintaining the oral hygiene of their patients. According to the present study, in the case of poor oral health of the patient, more than half (53.5%) of them sometimes had to terminate the orthodontic treatment of their patients. However, the results of the study showed that the orthodontists almost never used oral health education and reminder applications. Instagram was recognized as the most commonly used social network by orthodontist.

The results of this study indicate the need for specialists to have an efficient method of educating and reminding orthodontic patients about oral health. Given the lack of awareness and use of available applications by specialists and the absence of a suitable Iranian application, investment in designing or upgrading health reminder applications tailored to the culture and needs of society is recommended.

Dentin hypersensitivity is a prevalent problem, manifested as a short sharp pain. Researchers have used different lasers to treat this condition. The present study aimed to evaluate the effect of 980 and 810‑nm high‑level diode lasers on dentin hypersensitivity to determine proper laser parameters for clinical applications.

In this double‑blinded randomized clinical trial, seven patients with 60 teeth affected by dentin hypersensitivity were selected for the present double‑blind, randomized clinical trial. The patients’ teeth were randomly matched and assigned to three groups: Group 1:980‑nm diode laser; Group 2: 810‑nm diode laser; and Group 3: Control, which received only the guiding beam. The laser parameters were 1‑W power, continuous wave mode, a distance of 1 mm, no contact, a 45° irradiation angle, and a 30‑s exposure time using to‑and‑fro movements. The treatment consisted of two sessions with a 1‑week interval. Pain severity was determined with the visual analog scale (VAS) at all the study intervals using a dry ice spray. The data were analyzed with SPSS version 20 using one‑way ANOVA, repeated measures ANOVA, and least significant difference tests. Significance level was set at α = 0.05.

The changes in VAS were significant only in the first stage (P = 0.046). The mean VAS scores decreased over time in the 810‑nm and 980 laser groups. A comparison of VAS changes relative to the baseline revealed significant changes in VAS scores at all the time intervals with both lasers. The two 810 and 980‑nm laser groups did not exhibit any significant differences for 2 months postoperatively (P = 0.098).

The application of 810 and 980‑nm diode lasers at 1‑W power and an exposure time of 30 s was effective in decreasing pain in patients with dentin hypersensitivity, with no significant difference between these two lasers.

Dentin hypersensitivity is a common oral problem that occurs as a short and sharp pain. There are many techniques to treat this condition, the latest of which is laser treatment. The aim of this study was to evaluate the effect of two type of low-power diode lasers (660 nm and 810 nm) on dentin hypersensitivity in order to achieve an acceptable clinical application by adjusting the effective parameters.

In this randomized, double-blind clinical trial, sensitive teeth of 7 patients were divided into three groups with randomized matching

group I, treated with 660-nm diode laser irradiation; group II, treated with diode laser 810-nm and group III, the control group. Irradiation parameters for 660-nm and 810-nm diode lasers were a power of 30 mW and 100 mW, respectively, in contact and continuous mode, perpendicular to tooth surface with a sweeping motion. Treatments were carried out in four sessions, at weekly intervals. Data obtained were analyzed with SPSS 22, using one-way ANOVA, repeated measures ANOVA and LSD (least significant difference) test. Significance level was considered as a=0.05.

There were no significant differences in VAS score changes between the two laser groups after the intervention in the first, second and third weeks compared to baseline (P>0.05). These changes in the fourth week were significantly higher in the 810-nm laser group compared to the 660-nm laser group (P=0.04) and in the 660-nm laser group were more than the control group (P=0.02). Mean VAS scores at 1-week, 1-month and 2-month postoperative intervals were significantly lower in 810-nm laser group than 660-nm laser group and in the 660-nm laser group they were less than the control group (P<0.001).

The use of 660-nm and 810-nm diode lasers with a power of 30 and 100 mW, respectively, for 120 seconds was effective in reducing pain in patients with dentin hypersensitivity. However, the effect of 810-nm laser was more long lasting in reducing the dentin hypersensitivity than that of the 660-nm laser.

This study was conducted to assess the hardness of orthodontic brackets produced by metal injection molding (MIM) and conventional methods and different orthodontic wires (stainless steel, nickel‑titanium [Ni‑Ti], and beta‑titanium alloys) for better clinical results.
A total of 15 specimens from each brand of orthodontic brackets and wires were examined. The brackets (Elite Opti‑Mim which is produced by MIM process and Ultratrimm which is produced by conventional brazing method) and the wires (stainless steel, Ni‑Ti, and beta‑titanium) were embedded in epoxy resin, followed by grinding, polishing, and coating. Then, X‑ray energy dispersive spectroscopy (EDS) microanalysis was applied to assess their elemental composition. The same specimen surfaces were repolished and used for Vickers microhardness assessment. Hardness was statistically analyzed with Kruskal–Wallis test, followed by Mann–Whitney test at the 0.05 level of significance.
The X‑ray EDS analysis revealed different ferrous or co‑based alloys in each bracket. The maximum mean hardness values of the wires were achieved for stainless steel (SS) (529.85 Vickers hardness [VHN]) versus the minimum values for beta‑titanium (334.65 VHN). Among the brackets, Elite Opti‑Mim exhibited significantly higher VHN values (262.66 VHN) compared to Ultratrimm (206.59 VHN). VHN values of wire alloys were significantly higher than those of the brackets.
MIM orthodontic brackets exhibited hardness values much lower than those of SS orthodontic archwires and were more compatible with NiTi and beta‑titanium archwires. A wide range of microhardness values has been reported for conventional orthodontic brackets and it should be considered that the manufacturing method might be only one of the factors affecting the mechanical properties of orthodontic brackets including hardness.