fatemeh mazhari

 This in vitro study was conducted to assess the phototoxic effects of curcumin, nanocurcumin, and erythrosine on the viability of Streptococcus mutans (S. mutans) in suspension and biofilm forms.

 Various concentrations of curcumin (1.5 g/L, 3 g/L), nano-curcumin (3 g/L), and erythrosine (100 μM/L, 250 μM/L) were examined for their impact on planktonic and biofilm cultures of S. mutans, either individually or in conjunction with light irradiation (photodynamic therapy or PDT). A blue light-emitting diode (LED) with a central wavelength of 450 nm served as the light source. The results were compared to 0.12% chlorhexidine digluconate (CHX) as the positive control, and a solution containing neither a photosensitizer (PS) nor a light source as the negative control group. The dependent variable was the number of viable microorganisms per experiment (CFU/mL).

 Antimicrobial PDT caused a significant reduction in the viability of S. mutans in both planktonic and biofilm forms, compared to the negative control group (P<0.05). The highest cell killing was observed in PDT groups with curcumin 3 g/L or erythrosine 250 μmol/L, although the difference with PDT groups using curcumin 1.5 g/L or erythrosine 100 μmol/L was not significant (P>0.05). Antimicrobial treatments were more effective against planktonic S. mutans than the biofilm form.

 PDT with either curcumin 1.5 g/L or erythrosine 100 μmol/L may be suggested as an alternative to CHX to inactivate the bacteria in dental plaque or deep cavities. Nanocurcumin, at the selected concentration, exhibited lower efficacy in killing S. mutans compared to Curcumin or erythrosine.

The Bolton analysis is commonly used by orthodontists. The Bolton ratios of different populations are significantly different from the standard values of Bolton. This study sought to examine the Bolton's anterior and overall ratios in various malocclusion types in Mashhad, Iran, in contrast to the Bolton’s standards.

This descriptive-analytical study was conducted on 240 study models of patients (121 males and 119 females) in four groups (n= 60 cases) of normal occlusion, Class I, Class II, and Class III. The mesiodistal dimensions of the teeth were measured twice using a digital caliper. The anterior and overall ratios of Bolton were calculated. Statistical analysis was conducted utilizing SPSS 18.0.

The mesiodistal width of the maxillary lateral incisors in normal occlusion cases was greater than that in Class I, Class II, and Class III malocclusions (P<0.05). Conversely, the mesiodistal width of the maxillary first and second premolars was the greatest in Class II and the smallest in Class III malocclusion (P<0.05). Correlation was not observed between dental ratios (anterior and overall) and gender or malocclusion groups (P>0.05). Furthermore, the anterior ratio was significantly higher than the Bolton's standard in Class I and III malocclusion groups (P<0.05). The normal occlusion group's overall ratio was significantly lower than the Bolton's original ratio (P<0.05).

Implementing the Bolton analysis in the population of Mashhad, Iran should be approached with caution.

Many different kinds of chewing gum can increase the flow of saliva, and they have been proven to have anti-bacterial effects as well. The aim of this study was to compare the effect of natural turpentine and synthetic sugar-free gums on dental plaque pH after a sucrose challenge.
This randomized clinical trial was conducted on 15 subjects, who refrained from oral hygiene for two days and rinsed with 10% sucrose solution. Then for 30 minutes, they chewed one of three sugar-free gums: Van (natural), Orbit Complete, Orbit (synthetic), or one sugar-containing chewing gum (Banana). One group did not receive any gum (control group). Plaque pH was measured by the plaque sampling method before rinsing with sucrose, and 5, 10, 15, 20, and 30 minutes after chewing.
The lowest plaque pH drop was seen in the Orbit Complete group, and the highest was in the Banana group. The pH increased faster with Van and Orbit Complete gums. The plaque pH was more than baseline pH after 20 minutes in the Van and Orbit Complete groups (P All the three sugar-free gums were effective, although the pH recovery was higher and faster in the Van and Orbit complete groups.

To compare the efficacy of Mineral Trioxide Aggregate (MTA) and Modified Portland Cement (MPC) as pulpotomy medicaments in primary molars.
A sample of 54 children 4 to 6 years old of age, who had at least one primary mandibular second molar that needed pulpotomy were randomly placed in MTA (n = 28) or MPC (n = 26) groups. After completing the pulpotomy procedures, the teeth received a stainless-steel crown. Clinical and radiographic successes/failures were blindly evaluated at 6 and 12 months, and Fisher's exact test was used to analyze the differences.
At 6- and 12-month follow-ups, MTA and MPC had 100% clinical success rate. Radiographic success rates of MTA were 92.9% at 6 months and 89.3% at 12 months. While the rate for MPC group was 88.5% at both intervals. There was no statistically significant difference between the two groups.
The results of this investigation showed that treatment success rate with MPC was comparable to MTA pulpotomy. However, additional clinical research that considers long-term follow-ups is required to test the usefulness of MPC in the pulpotomy treatment of primary teeth.

Increased resistance of oral pathogens to conventional antimicrobial agents has led to the use of alternative methods to overcome microbial resistance. The purpose of this in vitro study was to evaluate the effect of antimicrobial photodynamic therapy on Streptococcus mutans.
In this in vitro study, a diode laser emitting a wavelength of 810nm was used in association with EmunDo as a photosensitizing agent. Suspensions of Streptococcus mutans were prepared and divided into six groups by treatment: 1) EmunDo, 2) diode laser irradiation (100mW, 90 seconds), 3) diode laser irradiation (300mW, 30 seconds); 4) EmunDo瘪 laser irradiation (100mW, 90seconds), 5) EmunDo瘪 laser irradiation (300mW, 30 seconds), 6) control (no treatment). Immediately and 24 hours after photodynamic therapy, the bacterial suspensions were cultured. After incubation at 37°C, viable microorganisms of Streptococcus mutans were counted and the results were reported in colony-forming units (CFU). Data were analyzed by repeated measures analysis of variance at significance level of 0.05.
According to the repeated measures analysis, no significant between-group differences were found in the number of Streptococcus mutans colonies, either immediately or 24 hours after photodynamic therapy (P>0.05). The number of Streptococcus mutans colonies increased significantly at 24 hours after photodynamic therapy compared to immediately after treatment in all groups (P Under the conditions used in this study, photodynamic therapy had no effect on viability of Streptococcus mutans. However, more evidence-based data are required regarding different photosensitizing agents and laser parameters for a definite conclusion.

Aim: To investigate the effect of Emdogain gel (EMD) in pulpotomized primary molars and its clinical and radiographic outcomes.
Methods and Materials: In this study, 18 lower second primary molars of nine children were treated by pulpotomy. The teeth were randomly assigned to the EMD (experimental) and Formocresol (control) groups in each patient (split mouth). Following removal of the coronal pulp and haemostasis, the pulp stumps were covered with Emdogain gel in the experimental group followed by application of resin-modified glass ionomer cement over the gel. In the control group, Formocresol (FC) was placed with a cotton pellet over the pulp stumps. Lastly, the teeth in both groups were restored with stainless steel crowns.
Nine children referred with clinical failure before/at two months follow up. The radiographic evaluation revealed furcation involvement and extensive radicular radiolucency in molars treated with Emdogain gel.
The present study showed the failure of enamel matrix derivative in pulpotomy of primary molars; therefore, we do not recommend using Emdogain as a pulpotomy agent for treatment of cariously exposed primary teeth
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Treatment of immature permanent teeth damaged by caries or trauma is usually a challenge to a dentist. Recently, revascularization process is performed to induce root development in immature necrotic teeth. The purpose of this report was to present a case of pulp revascularization in an immature necrotic tooth. Case Report: An 8-year-old boy was presented to the pediatric Department of Mashhad dental school with the chief Complaint of localized swelling on the anterior region of maxilla and a history of trauma to the maxillary right central incisor. Based on clinical and radiographic Findings, the diagnosis was pulpal necrosis with symptomatic apical abscess. Revascularization therapy was performed over multiple visits. At 6- month follow-up, in addition to complete healing of the periapical lesion, apex had been closed and dentinal wall thickness had been increased. At 12-month follow-up, pulp canal obliteration (PCO) was observed. At 24-month follow-up; tooth was asymptomatic and PCO had been. Considering the loss of periapical radiolucencies and root development of this tooth after a short period of time, it could be concluded that revascularization was an appropriate treatment method in immature necrotic teeth.

Impaction of premolar teeth is a common dental problem. Timelyandappropriatetreatmentof theseteethis important in preventingthe risk ofpossible problems, such as effectsonadjacent structuresand thepossibility ofpathological manifestation. Treatment of these teeth includes conservative orthodontic and/or surgical interventions. Few reports about management of impacted or unerupted second premolar are available. Case report: The patient was a 12-year-old girl with four unerupted second premolars. In radiographic examination, the right maxillary second premolar was in horizontal buccolingual direction and the mandibular second premolars were distoangular. All second primary molars were extracted and space-maintainers were placed in both jaws. After eight months, the maxillary second premolar teeth and mandibular right second premolar erupted spontaneously. In subsequent visits, due to worsening of eruptive position of the left second premolar, bone mass covering the crown and refusing surgical exposure and orthodontic repositioning treatment, by the patient and her parents, this tooth was removed surgically. Conservative approach should be considered as a non-invasive treatment option before surgical ororthodontic treatment plan in management of impacted second premolar teeth. However, factors such as the developmental disturbance of other permanent teeth, oral hygiene and patient compliance should be considered in planning an appropriate treatment approach for each patient.

Heat generated within tooth during clinical dentistry can cause thermally induced damage to hard and soft components of the tooth (enamel, dentin and pulp). Geometrical characteristics of immature teeth are different from those of mature teeth. The purpose of this experimental and theoretical study was to investigate thermal changes in immature permanent teeth during the use of LED light curing units (LCU). This study was performed on the second mandibular premolars. Experimental investigation was carried out for recording temperature variations of different sites of tooth and two dimensional finite element models were used for heat transfer phenomenon in immature teeth. Sensitivity analysis and local tests were included in the model validation phase. Overall thermal stimulation for 30 seconds by using a low-intensity LED LCU increased the temperature from 28°C to 38°C (a 10°C increase) in IIT and PIT. When a high-intensity LED LCU was used, tooth temperature increased from 28°C to 48°C (a 20°C increase). The results of the experimental tests and mathematical modeling illustrated that using LED LCU on immature teeth did not have any detrimental effect on the pulp temperature. Using LED LCU in immature teeth had no effect on pulp temperature in this study. Sensitivity analysis showed that variations of heat conductivity might affect heat transfer in immature teeth; therefore, further studies are required to determine thermal conductivity of immature teeth.

Amelogenesis imperfecta is a group of genetic disorders that affects both the morphology and quality of tooth structure. Although the disease entity is primarily associated with abnormalities of dental and oral structures, it has been reported to be associated with a few syndromes. A 9-year-old girl with minor thalassemia referred to the Department of Pediatric Dentistry of the Mashhad Faculty of Dentistry with a complaint of sensitivity of first permanent molars. Dental findings consisted of amelogenesis imperfecta, microdontia, posterior cross bite and taurodontism. This is the first report of thalassemia accompanied with amelogenesis imperfecta. Although the patients often are non-symptomatic, the trait can be passed on to a child and if both parents carry the trait, the child could develop a more severe form of the disease; therefore, early diagnosis is important.

Treating caries-susceptible pits and fissures with resin sealants enjoys wide acceptance as a preventive strategy. The aim of this study was to evaluate the one-year clinical performance of a polyacid-modified resin composite material (Dyract) in comparison to a composite resin material (Helioseal F).
Using a half-mouth design, 100 sealants were placed on the sound first permanent molars of 50 children aged between six and 10 years. Half of the teeth (n = 50) were sealed with Dyract and half (n = 50) with Helioseal F. Teeth were evaluated at baseline, 3, 6 and 12 month intervals. The qualities of the restorations were evaluated in accordance with modified U.S. Public Health Service (USPHS) codes and WHO criteria for the presence of dental caries. The data were analyzed according to the Mann-Whitney test and the spearman correlation.
0.05). Decayed/Missing/Filled Teeth index (DMFT) had convert relation with retention and marginal integrity in both materials.
In this study there was no clinical difference between the two sealants. Polyacid Modified Resin Composite (PMRC) materials have low wear resistance compared to resin composite, but the two curing reactions that occur in PMRC materials might have improved their mechanical retention in the long term. Therefore, further study on these characteristics is recommended.

Despite advances in the oral health of children in recent decades, early childhood caries (ECC) continues to pose a serious threat to child welfare. The purpose of this study was to determine prevalence and severity of ECC in 6-60 month old children in relation to socioeconomic factors, feeding practices and oral health behaviors in Quchan.
This cross-sectional study included almost all children enrolled in Quchan
s day care centers; 232 six to sixty months children were examined. Social and behavioral information were obtained from parents through a self-administered questionnaire. ECC and severe ECC (S-ECC) were diagnosed based on NIDCR and WHO recommendations.
The prevalence of ECC and S-ECC were 59% and 25%, respectively. The overall mean of d2mfs (with cavitated carious surface lesions) and d2psmfs (with cavitated and non-cavitated carious surface lesions) were 2.1 ± 4.45 and 3.80 ± 5.34, respectively. The variables significantly associated with ECC or S-ECC were socioeconomic status, frequency of bottle-feeding, snacking frequency, probable age of starting tooth brushing, person responsible for child’s oral health care and eruption age of the first tooth.
This study demonstrated that the prevalence of ECC was high among of preschool children in the city of Quchan. It is recommended to increase knowledge of parents about proper feeding habits and oral health practices, and also preschool children accessibility to dental services.

The inflammatory changes in gingiva as well as periodontal diseases are the most common oral conditions found in diabetic patients. The objective of the present investigation was to compare the oral health and periodontal disease status in diabetic and non diabetic children and adolescents. Cases were composed of 68 registered diabetic individuals aged 5-18 years old. The control group was composed of 68 non-diabetic sex and age-matched persons, who were among the out-patient visitors of Mashhad School of Dentistry. A questionnaire was used to collect information from medical records and clinical examinations. The statistical analysis was conducted in order to assess OHI-S, PI and GI indices in each patient. The mean OHI-S was 1.56±0.59 and 1.63±0.51 in diabetic and non-diabetic children respectively. The mean PI was 1.42±0.85 in diabetic and 0.71±0.54 in non-diabetic children. The mean GI was 1.20±0.45 and 0.77± 0.50 in diabetic and non-diabetic children respectively. Although there was no significant difference between the two groups regarding their oral hygiene status, diabetic children had higher frequencies of periodontal diseases and gingivitis compared to sex and age-matched non-diabetic controls. Therefore, it is necessary to design and promote periodontal disease prevention programs for young diabetic patients.