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The present study aimed at evaluating the onset and duration of the pubertal growth spurt in skeletal class I and II individuals, utilizing the cervical vertebral maturation (CVM) method.

A total of 132 Iranian individuals (class I=68, class II=64) were evaluated retrospectively in this cross-sectional study. Subjects were between 9 and 16 years old and had never undergone orthodontic treatment. Lateral cephalograms of the subjects were independently traced by two examiners to determine their skeletal class, employing Steiner and Wits analyses. Baccetti's CVM method was employed to assess skeletal maturation. The onset and duration of the pubertal growth spurt (CS3-CS4 interval) was analyzed among the two classes and genders using the Independent Samples t-Test.

The duration of the pubertal growth spurt equaled 1.62 (±1.33) years in skeletal class I subjects and 1.34 (±1.21) years in skeletal class II subjects. The difference in duration between the two classes, with an average of 0.28 years (3.36 months), was statistically significant (p<0.001). The average onset age of growth spurt was estimated to be 11.91 (±1.32) years in class I subjects and 11.41 (±1.19) years in class II subjects, but this difference was insignificant (p=0.110). The onset and termination of the pubertal growth spurt occurred later by 1.49 years (p<0.001) and 1.27 years (p<0.001), respectively, in male subjects.

Class I and II subjects had similar growth spurt onset ages, but class II spurt duration was shorter by 3.36 months. Females experienced longer and earlier growth spurts compared to males.

This study aimed to assess the effect of adding propolis to glass-ionomer cements (GICs) on their antimicrobial and physical properties.

For the evaluation of the antimicrobial properties of conventional (Fuji II) and high-viscous (Fuji IX) GICs containing propolis, 120 glass-ionomer disks with the dimensions of 10 × 2 mm were prepared in three groups of control, 25% propolis, and 50% propolis. Then, these GICs were placed in the Streptococcus mutans culture media. After 24 h of incubation, the inhibition zone diameters of the disks were recorded. For the evaluation of flexural strength, 30 samples (six groups of 5) with the dimensions of 2 × 2 × 25 mm were prepared and measured by a universal testing machine. The Kolmogorov-Smirnov test and SPSS software (version 21.0) were used for statistical analysis and ensuring normal data distribution. One-way analysis of variance was used for comparing the mean values of the groups, and Tukey’s HSD test was used for pairwise comparison of the groups. The duration of the study setup was 9 months.

An inhibition zone was not observed in any of the study groups. There was no significant difference between the flexural strength values of the three groups of the Fuji IX (P = 0.905) and also between the three groups of the Fuji II (P = 0.096). However, the Fuji IX samples had higher flexural strength values than the Fuji II glass-ionomer specimens (P < 0.001).

The addition of different concentrations of propolis aqueous extract to conventional and high-viscous GICs did not have a significant effect on their antimicrobial properties and flexural strength.

Recently, toothpastes containing herbal antimicrobial ingredients have gained popularity due to their reduced side effects. This study aimed to compare the antimicrobial efficacy of two herbal toothpastes and a nonherbal type on pathogens responsible for caries and periodontal disease.

Full and 1:3 concentrations of two herbal toothpastes (Himalaya® and Herbex®) and a nonherbal type as the positive control (Crest® cavity protection) were prepared. Sterile distilled water was considered as the negative control. Streptococcus mutans, Streptococcus sobrinus, Lactobacillus casei, and Actinobacillus actinomycetemcomitans (A.a) were cultivated on agar plates and incubated after adding toothpaste preparations. The diameter of the inhibition zone was measured in millimeters. Two-way analysis of variance and Tukey Post-hoc tests were applied at P <0.05.

The mean margin diameter was higher in full concentration than the diluted 1:3 formula for all examined toothpastes (P <0.001). All three toothpaste types exerted a significant antimicrobial effect compared to the negative control (P <0.05). The antimicrobial effect of Herbex® on S. sobrinus was significantly lower than the positive control, and it was significantly less effective against S. mutans compared to Himalaya (P <0.05). Furthermore, the efficacy of Himalaya® on L. casei and A.a was significantly lower than the positive control (P <0.05). No statistically significant differences were observed in other pair comparisons.

Considering the observed efficacy of herbal toothpastes against cariogenic bacteria and periopathogens, they potentially qualify as complementary agents for self-care oral hygiene procedures.

Objectives:

 This study aimed to assess the antibacterial effects of xylitol and Stevia rebaudiana (S. rebaudiana) ethanolic extract on oral biofilm.

Methods :

A total of 96 acrylic discs were divided into two main groups for inoculation with Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus). Each group consisted of 6 subgroups including a positive control subgroup and 5 subgroups of discs immersed in 1% or 3% xylitol solutions, 2 or 4 mg/mL S. rebaudiana, or a combination of 3% xylitol and 4 mg/mL S. rebaudiana. After incubation, the discs were rinsed and transferred to fluid universal medium. The solutions were cultured on specific culture media and incubated. The colony-forming units (CFUs) were counted for each disc. The structure of biofilm in each group was evaluated under a scanning electron microscope (SEM).

Results :

ANOVA revealed significant differences between the subgroups in both S. mutans and S. sobrinus groups (P=0.03 and P=0.01, respectively). In S. mutans group, the logarithmic mean of colony count in the positive control subgroup was 6.75 while this value was significantly lower in 2 mg/mL (5.81) and 4mg/mL (5.92) S. rebaudiana subgroups using the post hoc Dunnett's test (P=0.01 and P=0.04, respectively). The three other subgroups did not show significant differences. In S. sobrinus group, all five experimental subgroups demonstrated significantly lower colony count than the positive control group (P<0.05).

This in vitro study aimed to evaluate the microshear bond strength (μSBS), microhardness and morphological characteristics of primary enamel after treating with sodium fluoride (NaF) and acidulated phosphate fluoride (APF).

Forty-eight primary canines were cut into mesial and distal sections and assigned to five groups randomly: group 1 (immersed in saliva as a control), group 2 (treated with NAF and immersed in saliva for 30 minutes), group 3 (treated with APF and immersed in saliva for 30 minutes), group 4 (treated with NAF and immersed in saliva for 10 days), and group 5 (treated with APF and immersed in saliva for 10 days). Composite resin (Filtek Z250) was bonded on the specimens (n=15) for measuring the μSBS. After storage in 37°C artificial saliva for 24 hours, µSBS and Vickers hardness tests (10 readings) were performed. The data were analyzed using one-way ANOVA and Kolmogorov-Smirnov, Levene’s and Tukey HSD tests (P<0.05). Morphological analysis of enamel and modes of failure were carried out under a scanning electron microscope (SEM) on two remaining specimens.

Significant differences in μSBS were only noted between groups 2 and 4 (P=0.024). Group 3 showed a significant decrease in hardness after storage in artificial saliva (P<0.001), with a significantly lower hardness than the other groups (P<0.001). The SEM observations showed irregular particles in groups 3 and 5; uniform, smooth and thin coats were seen in groups 2 and 4.

Fluoride therapy with NaF and APF gels prior to restorative treatments had no adverse effects on the microshear bond strength.

In recent years, the use of herbal oral care products has been taken into consideration for reducing dental plaque accumulation. Propolis has been widely used in medicine due to its multiple biological properties. The aim of this study was to evaluate the antiplaque efficacy of an herbal toothpaste containing propolis in comparison with a control group.

This single-blind parallel clinical trial was conducted among 60 dental students. The baseline plaque index was evaluated using a plaque in-dicator one hour after brushing without toothpaste. Participants were randomly as-signed to two groups: (A) herbal toothpaste with propolis, and (B) herbal toothpaste without propolis. After four weeks, the plaque index was re-examined and recorded. Quantitative variables were analyzed by independent t-test, and the mean and standard deviation (SD) were reported. P<0.05 was considered statistically significant.

The mean plaque index differences were not significant between the two groups at the beginning of the study, while there was a significant difference after four weeks (P˂0.001). The results signify an approximate 1.7-unit reduction in the mean plaque index of subjects using toothpaste with propolis in comparison with a 0.7-unit reduction in subjects using toothpaste without propolis.

The herbal toothpaste containing propolis was more effective in reducing plaque accumulation in comparison with the control group. Considering the effect of propolis-containing toothpastes on the reduction of dental plaque accumulation, these can be used as an effective oral hygiene product.

Since fluoride therapy is usually the first step of treatment in pediatric dentistry and it may interfere with other treatments, such as composite fill-ing, this study aimed to evaluate the possible effects of topical pre-fluoride therapy on marginal microleakage of composite restorations in deciduous teeth. In this in-vitro study, 30 deciduous canines were randomly allocated to five groups: 1.23% acidulated phosphate fluoride (APF) gel was used in two groups, while 2% sodium fluoride (NaF) gel was used in the other two groups. Thirty minutes and two weeks after fluoride therapy, Class V cavities were prepared and restored using composite resins. After thermocycling, the teeth were soaked in 0.5% fuchsine solution and were sagittally sectioned in half. The extension of dye penetration into the occlusal and gingival walls was investigated un-der a stereomicroscope at ×30 magnification and scored using a 0-3 scoring system. Data were analyzed using Kruskal-Wallis and Wilcoxon signed-rank tests. Marginal microleakage was neither affected in enamel walls (P=0.213) nor in dentinal walls (P=0.851). The scores of microleakage in enamel walls were lower than that in dentinal walls, and this difference was statistically significant (P<0.05). Topical fluoride therapy using 1.23% APF or 2% NaF gel before the placement of composite resin restorations has no negative effect on marginal microleakage.

In recent years, beneficial effects of herbal hygienic products and toothpastes have significantly been emphasized. This study sought to assess the effects of Masdent toothpaste which contains Pistacia Lentiscus (PL) extract on plaque index and Streptococcus mutans(SM) and Lactobacillus (LB) count in saliva.
This study was conducted on 60 students aged 18-20 years. Participants were asked to brush their teeth twice a day for four weeks with the assigned toothpaste, Masdent toothpaste which contains PL extract in the case group and Crest toothpaste in the control group. Plaque index was recorded at the onset and end of the study, and salivary samples were taken for SM and LB colony count. Mann-Whitney, independent t- and Wilcoxon tests were used for data analysis. P Number of SM and LB colonies significantly decreased in both groups(P Use of herbal toothpaste containing PL extract and Crest toothpaste had similar effects and both significantly decreased SM and LB salivary counts as well as the plaque index.

In the recent years, herbal oral hygiene products have gained increasing attention. The aim of this study was to assess the effects of three types of mastic gums on the level of Mutans streptococci, Lactobacilli and pH of the saliva. Forty-two students in the age range of 20-30 years were divided into three parallel groups; each of them separately used pure mastic gum, xylitol mastic gum and probiotic mastic gum for three weeks. Number of microorganisms and pH of the saliva were assessed before and after the intervention. The data were analyzed using Wilcoxon Signed Rank, paired-sample-t, Kruskal-Wallis and Tukey’s post-hoc tests and One-way ANOVA. Level of Mutans streptococci showed a significant reduction compared to its baseline value in all three groups (P<0001 for all). Salivary Lactobacillus count increased in the groups using pure and xylitol mastic gums but decreased in the group using probiotic type, albeit these changes were only significant in the group using probiotic mastic gum (P<0.001). Use of pure and xylitol mastic gums increased the pH of the saliva but not significantly. In the group using probiotic mastic gum, the pH of the saliva decreased significantly (P=0.029). Three weeks use of all mastic gums resulted in a significant drop in the number of Mutans streptococci in the saliva. However, the drop in the saliva pH due to the use of probiotic mastic gum is not in favor of dental health.

Recently, self-etching fissure sealants have been introduced to reduce technical sensitivity; however, their efficacy should be assessed. The aim of this study was to assess of the microshear bond strength of self-etching and conventional fissure sealants. Thirty non-carious third molars were randomly divided into three groups (N=10). Microcylinders of Concise fissure sealant were bonded to prepared buccal and lingual surfaces using the two following procedures. In the first group, phosphoric acid was used to prepare the substrate; whereas in group two, Concise was used in combination with Prompt L-Pop. In group 3, a self-etching fissure sealant (Enamel Loc) was utilized per se. After 24 hours, the samples were subjected to 500 rounds of thermocycling and shear bond testing using a microtensile tester machine with a crosshead speed of 0.5mm/min. Data were analyzed using one-way repeated measure ANOVA and Bonferroni Post HOC tests (SPSS version 16). The mean and standard deviation of microshear bond strength of the groups were as follows: Group 1: Concise+ etching (14.59 ± 1.19 MPa), Group 2: Concise+Prompt L-Pop (12.86 ± 1.98 MPa), and Group 3: Enamel Loc (5.59 ± 0.72 MPa). One-way ANOVA revealed that all the differences were significant and the conventional sealant exhibited the highest mean bond strength. Conventional sealant using phosphoric acid etch application prior to fissure sealant application demonstrated more bond strength in comparison with that of self- etch bonding and self- etch sealant.

This paper presents a case with dentinogenesis imperfecta (DI) associated with osteogenesis imperfecta. Systemic and dental manifestations of OI and its medical and dental treatments are discussed in this paper. A 5-year-old child with the diagnosis of OI was referred to the Dental School of Shaid Beheshti University of Medical Sciences. On clinical examination yellow/brown discoloration of primary teeth with the attrition of the exposed dentin and class III malocclusion was observed. Enamel of first permanent molars was hypoplastic. Radiographic examinations confirmed the diagnosis of DI. A histological study was performed on one of the exfoliating teeth, which showed abnormal dentin. Primary teeth with DI were more severely affected compared topermanent teeth; enamel disintegration occurred in teeth with DI, demonstrating the need for restricts recalls for these patients

The extreme vulnerability to decay in pits and fissures on the occlusal surfaces of the teeth has prompted dental scientists to seek methods of caries prevention. Various criteria, such as bond strength, micro leakage and marginal seal are assessed in the evaluation of sealants. Motivated by the role of pit and fissure sealants in caries prevention, the aim of this study was to compare the micro leakage of Enamel Loc sealant, Concise and Concise +Prompt L-pop resin-based sealants.

An in vitro study was undertaken using thirty extracted third molars. The teeth were divided into three groups; an experimental group using Enamel Loc as a pit and fissure sealant, a group using Concise and a group using Concise +Prompt L-pop. The teeth were kept in methylene blue dye 2% for 4 hours, sectioned samples were observed with stereomicroscope for the extent of dye penetration and scores were based on Williams and Winter criteria. Three groups of data were statistically analyzed using SPSS 18. Non-parametric Kruskal-Wallis test was used to detect differences among groups (p>0/001).

The Enamel Loc sealant micro leakage was significantly more than the two other groups (p>0/001). Furthermore, Concise micro leakage was significantly less than Concise +Prompt L-pop group (p>0/001).

The Enamel Loc sealant performed worse in terms of sealing ability than the Concise and Concise +Prompt L-pop resin-based sealants.

Early childhood caries (ECC) is a severe type of dental caries affecting infants and pre-school children. Because of the infectious nature of the disease, the immunologic response by the host plays an essential role in its development. This study investigated the association between the presence of salivary sCD14 and ECC. This study was carried out on 40 healthy children, of whom 20 were caries-free (CF) and 20 had ECC, within the ages of 36 to 71 months. Unstimulated saliva of the children was collected with disposable needle-less syringe from buccal and labial vestibules. Seven children with ECC received complete treatments. Saliva was collected for a second time after 3 months from this group. The sCD14 levels in salivary samples were analyzed by ELISA method. Mean concentrations of sCD14 in ECC and CF groups were 57.82 and 31.92 ng/ml respectively (p=0.008). After three months, the mean concentration of sCD14 among the treated children decreased to 11.38 ng/ml, which was significantly lowercompared to that of ECC children before intervention (p<0.001), and also CF children(p<0.05). The increased levels of sCD14 can be considered as a markerof inflammation and innate immune response during ECC.

The presence of fluoride in oral fluids, is necessary for prevention of dental caries. The aim of this study was to determine the extent of fluoride retention in saliva after brushing with two Iranian fluoridated toothpastes, Nasim and Crend in comparison with MacLeans & Crest. Ten adults used a nonfluoride dentifrice for 10 days before the experiment and between different stages of the experiment. The dentifrices included Nasim and MacLeans (with sodium monofluorophosphate) and Crend and Crest (with sodium fluoride). In each procedure, participants brushed their teeth with 1.5 gr of the dentifrices under trial for 1 minute. Saliva samples were collected at baseline, 1, 30, 60 120 minutes after tooth brushing and fluoride ion were measured by potentiometry technique. The data were analyzed by Repeated Measurements, Paired t, One Way ANOVA and Tukey tests. All dentifrices under this trial, had the highest fluoride concentration in saliva 1 minute after brushing (P<0.005) and after that time fluoride concentration decreased gradually. Crest toothpaste in comparison with Crend had higher fluoride retention in the 60 and 120 minutes [60 minutes: (0.9824±0.0988, 0.5173±0.770) (P<0.005) 120 minutes: (0.8103±0.0615, 0.3651±0.0580) (P<0.008)]. The Crest dentifrice showed the most fluoride retention in saliva, MacLeans and Nasim dentifrices had similar values of fluoride retention while the Crend dentifrice showed the least values of fluoride retention.

Determination of need to orthodontic treatment is one of the main problems in our daily practice. Therefore, the aim of this study is to evaluate the orthodontic treatment needs of 12 – 13 year old students in Gorgan in years 2002-2003, using IOTN (index of orthodontic treatment need). Methods & Materials: A descriptive study using the technique of observation and interview has been performed by means of chart, ruler, tongue blade and color photographs of aesthetic component of IOTN. The method of sampling was cluster sampling and 793 individuals of urban and rural school children in Gorgan were examined. According to dental health component (DHC) of ITON, 16.2 percent of school children showed great need and 16.9 percent moderate need to treatment and the frequency of slight or no need was 66.6 percent. The aesthetic component (AC) of IOTN in school children resulted in 7.1 percent great need, 20.9 percent moderate need and 71.9 percent no need. This study showed that the differences between IOTN values for boys and girls were not statistically significant the orthodontic treatment need in rural school children as significantly greater than urban school children, but most of them had no need or had slight need of orthodontic treatment.

In this study oral and teeth’s health status of 12 and 15 years old boys of Tehran deaf’s schools was evaluated in order to planning treatment programs. Methods & Materials: one hundred and three 12 and 15 year deaf student were examined and DMFT, CPITN, dental treatment needs and also prevalence of malocclusion, fluorosis and traumatic injuries of teeth were determined. In this study, the average of DMFT was 3.59±2.43 and the percent of caries free was %10. Evaluation of CPITN showed that the average of healthy sextants in 12 years old children was 4.75±1.23 and in 15 years old was 4.56±1.60. %92 of the students needed to have a kind of dental treatment and %64 needed to learn oral hygiene instructions. The high prevalence of tooth decay and dental needs of this population shows that hearing loss can be an effective factor in the oral health.