mohammad hashem hosseini

Probiotics depend on efficient safeguarding during their journey through the gastrointestinal tract, with robust mechanisms guaranteeing their viability and ensuring their beneficial impact once they reach the gut environment. Since the activity and viability of probiotic bacteria are important through gastrointestinal and colonizing conditions, Lactobacillus acidophilus NCFM was entrapped in Persian gum (PG) and soy protein isolate (SPI) complex coacervate (CC) to protect and transport them in the gastrointestinal environment. The microorganisms loaded into microcapsules with a SPI: PG ratio of 2:1, were generated with a high encapsulation efficiency of 93.80% using complex coacervation. The study delved into the survival rates of both free and encapsulated cells, as well as their release patterns in simulated gastric and intestinal juices across varied pH levels (1.2, 4, and 7.5), alongside the presence of respective digestive enzymes (pepsin and pancreatin). Results showed that the release rate of bacteria from the capsule was 96.66% after 24 hours. The number of free and encapsulated cells was reduced by 4.03 Log CFU/mL and 2.43 Log CFU/mL in SGJ (pH 1.2), respectively. The findings underscore that the PG-SPI complex coacervate exhibits substantial protection effects against Lactobacillus acidophilus.

Severe skeletal class III malocclusions usually need a combined treatment of orthodontics and orthognathic surgery. Knowing about changes occurred following such treatments lead to improve facial esthetics and better treatment results.
This study was done to determine cephalometric changes of facial soft tissue after combined treatment in patients with skeletal class III problem.
25 patients with skeletal class III discrepancy who needed a combined treatment, were selected. Changes in nasolabial angle , upper lip and lower lip to E-line distance, angle of convexity , lip-chin-throat angle and lower anterior facial height were measured before and 6 - 12 months after surgery. Changes in parameters were analyzed with Paired t-test.
Upper lip to E-line distance (P Clinical changes in the soft tissue following a combination of orthodontic treatment and orthognathic surgery in patients with skeletal class III discrepancy are significant while these changes mostly improves esthetics of patient’s facial profile.

Rebonding of isolated brackets is an economic option that can be conducted using available in-office or commercial recycling methods. Nowadays, lasers are known as an efficient modality for composite removal, but there is not much information available about using lasers for removal of adhesive remnants from the ceramic bracket base.
Fifty human premolar teeth were divided into five groups. Samples in all groups were bonded to ceramic brackets. Brackets in four groups were debonded and the remaining adhesive was removed by Er:YAG laser, Er;Cr:YSGG laser, sandblasting or direct flame. After removing adhesives from the tooth surfaces by carbide bur, the recycled brackets were bonded again. in the control group, new ceramic brackets were bonded. Finally, all brackets were debonded by universal testing machine and their shear bond strength (SBS) was measured. The adhesive remnant index (ARI) was calculated under a stereomicroscope at x10 magnification. Data were analyzed using one-way ANOVA and Tukey’s test.
SRS values showed no significant difference among the five groups (P=0.568). The highest SRS was noted in the control group (7.46±1.4 MPa), followed by Er:YAG laser group (7.40±1.24 Mpa) and the lowest was noted in the flame group (6.32±2.3 Mpa). ARI scores indicated that most of the adhesive remained on the tooth surface in all groups
Recycling of ceramic brackets with Er:YAG laser is an efficient in-office method which causes the least damage to the bracket base. However, all methods of bracket recycling showed acceptable SBS.

Application of zirconia in dentistry has increased due to its good properties. Since zirconia is not possible to be etched, evaluation of the other methods of surface treatment is important.
The aim of this study was to evaluate zirconia surfaces treated by different output powers of Er: YAG laser and sandblasting technique by scanning electron microscope (SEM).
15 specimens were prepared of 3Y-TZP ceramic material. After polishing of all the samples, divided into 5 groups; control group, 1.5 W Er: YAG laser irradiated group, 2.5W Er: YAG laser irradiated group, 3.5 W Er: YAG laser irradiated and sandblasted group. Then SEM image of each group were prepared and analyzed.
The SEM images of study groups showed there is no significant difference between control group and laser groups at × 3000, but at the more magnifications (× 15000 and × 60000), with increasing laser power, surface roughness and deformation of crystals increases. SEM of Sandblasted group showed a change in surface texture with the formation of microretentive grooves and deformation of zirconia crystals shape.
By increasing the Er: YAG laser power on zirconia ceramics, the surface roughness increases but not impressive. Application of sandblasting technique on zirconia provides greater surface roughness than Er: YAG laser treatment. 1.5 W (150 mJ) Er: YAG laser radiation has no significant effect on surface morphology of zirconia but 2.5 W (250 mJ) and 3.5 W (350 mJ) outputs, change the surface morphology.

The aim of this study was to evaluate the degree of pain and discomfort experienced for 1 week after miniscrew insertion using a questionnaire survey.
Thirty-nine miniscrews were inserted in the mandible and maxilla of 33 patients with a self-drilling JB head type miniscrew under local anesthesia. Patients were asked to rate the degree of pain and discomfort experienced on a visual analog scale (VAS) after 1 hour, 12 hours, 1 day, and 1 week . Data were analyzed using the Statistical Package for the Social Sciences version 22 software. Repeated measures analysis of variance (ANOVA) with considering the jaw, side of insertion, and length of miniscrew as a between subject factor was used.
There was no significant association between the length of miniscrew (P = 0.448), the jaw (P = 0.870), and the side of the insertion (P = 0.346) and causing pain. The maximum degree of pain experience was in 1 hour after insertion that was 48.79 mm in VAS scores, which started to decrease significantly after 12 hours, 1 day, and 1 week as the minimum intensity of the pain was week after the miniscrew insertion that was 2.31 mm in VAS scores.
On the basis of the patient responses, it can be concluded that miniscrew could be an acceptable option in orthodontic treatments.

Application of zirconia ceramics has increased. Since the commonly used surface treatment for porcelain, i.e. acid etching is not efficient for zirconia surfaces, evaluation of other surface treatment methods for zirconia is important. The aim of this study was to compare the shear bond strength (SBS) of metal brackets to zirconia treated with different powers of Er:YAG laser, sandblasting and silane.
In this experimental study, five blocks of 3 mol% yttria stabilized tetragonal zirconia ceramics (3Y-TZP-A) were cut into small cubes. After the sintering process, 72 samples were assigned to six groups (n=12). The first group did not receive any surface treatment. The second, third and fourth groups were irradiated with Er:YAG laser with 1.5 W (150 mJ), 2.5 W (250 mJ) and 3 W (300 mJ) powers, respectively in a long pulse mode for 20 seconds. The samples in the fifth group were sandblasted. The sixth group samples were silanized. After bonding of brackets to the samples, they were stored in distilled water, thermocycled and their SBS was measured by a universal testing machine. Mode of failure was assessed by a stereomicroscope.
The SBS of brackets to zirconia in groups one to six was 0.31±0.23, 0.51±0.14, 1.11 ±0.40, 3.32±1.52, 9.5±2.99 and 3.88±2.20 MPa, respectively. ANOVA revealed a significant difference among the six groups. Tamhane’s test showed that the SBS in group five was significantly higher than that in the other groups. Bond failure occurred at the adhesive/zirconia interface in all groups.
Surface treatment of zirconia with sandblasting provided appropriate bond strength of brackets for clinical applications. But, Er:YAG laser and silane did not create sufficient SBS to zirconia surfaces.

The purpose of this study was to evaluate amalgam surfaces treated by different output powers of erbium-doped yttrium aluminum garnet (Er:YAG) laser by scanning electron microscope (SEM). Twenty-one amalgam blocks (8 mm × 8 mm, 3 mm thickness) were prepared by condensing silver amalgam (into putty impression material. After keeping them for 24 hours in distilled water, they were divided into 7 groups as follow: G1: Er:YAG laser (1 W, 50 mJ), G2: Er:YAG laser (2 W, 100 mJ), G3: Er:YAG laser (3 W, 150 mJ), G4: Sandblast, G5: Sandblast + Er:YAG laser (1 W, 50 mJ), G6: Sandblast +Er:YAG laser (2 W, 100 mJ) and G7: Sandblast +Er:YAG laser (3 W, 150 mJ). Then after preparation of all samples, they were examined by SEM. The SEM results of amalgam surfaces treated by different output powers of Er:YAG laser showed some pitting areas with non-homogenous irregularities It seems that the application of sandblasting accompanied by Er:YAG laser irradiation can provide proper surface for bonding of orthodontic brackets.

Recent use of lasers for porcelain surface treatment for adhesion of brackets to restorations has not only showed some promising results, but is also accompanied with less undesirable effects among other advantages. The purpose of this study is the comparative electron microscope evaluation of feldspathic porcelain surfaces under irradiation by Neodymium-Doped Yttrium Aluminium Garnet (Nd:YAG) with different powers (0.75, 1.5 and 2W) via the acid etching with hydrofluoric acid (HF) technique. The glazed porcelain samples were obtained by duplicating labial surfaces of maxillary central incisor teeth. The specimens were randomly treated by 4 different methods. Group1 was etched with hydrofluoric acid 9.6%. Samples in group 2 to 4 were also irradiated by Nd:YAG laser with different powers: 0.75, 1.5 and 2W. Then the samples were prepared for evaluation by scanning electron microscope (SEM). Etching quality from a porosity point of view was similar for group2 and HF group. Laser with power of 0.75W has little potential to create mechanical porosity. In regard of the results of this study, it is possible to benefit from Nd:YAG laser with appropriate parameters for surface conditioning.

The number of complaints filed by patients at the Iranian Medical Council is rising in recent years. Some of the complaints are related to orthodontics malpractice cases. The aim of this study was to investigate the frequency of orthodontics malpractice complaints filed against either specialists or general dental practitioners according to the final decree registered at the Iranian Medical Council. This descriptive study was designed to examine the relevant documents filed since 1372 (1994), which received rulings by the Iranian Medical Council. Of the 54 orthodontics cases, 31 were filed against general practitioners, 16 against orthodontists, 3 against pediatricians and 4 against so-called denturists. A total of 25 cases were acquitted of all charges, 3 cases were punished verbally, 33 cases received written notice and 4 cases of dentuirists were referred to court. Among all, 27 malpractice cases were against removable and 26 involving fixed orthodontic treatments. Twelve convicted individuals were also charged with lack of professional care, 14 with lack of expertise, and 2 for negligence. This study shows a considerable rise in convicted malpractice cases filed against general dental practitioners (88%), according to registered cases at the Iranian Medical Council over the past ten years. For prevention and control of such events, this result suggests that more education and closer supervision as well as enforcement of regulations are required by authorities.