جستجوی مقالات مرتبط با کلیدواژه "deciduous" در نشریات گروه "پزشکی"

This study aimed to compare the microshear bond strength (µSBS) of two types of universal adhesives to primary dentin following self-etch (SE) and total-etch (TE) techniques.

In this in vitro experimental study, 50 extracted sound primary first and second molars were randomly assigned into five groups (n=10). The groups were treated as follows: All Bond Universal (ABU) using the self-etch (SE) technique, Scotchbond Universal (SBU) using the SE technique, ABU using the total-etch (TE) technique, SBU using the TE technique, and Adper Single Bond 2 (ASB2) as the control group, after exposing the occlusal dentinComposite cylinders were bonded to dentin and underwent µSBS test. Data were analyzed by two-way ANOVA and Tukey’s test (alpha=0.05).

All experimental groups showed significantly lower µSBS than the control group (P<0.05). However, the difference in µSBS was not significant among the experimental groups (P>0.05).

The results showed higher µSBS of ASB2 (fifth-generation adhesive) than both universal adhesives (SBU and ABU) in SE and TE techniques. The µSBS to primary dentin depended on both adhesive type and technique.

Statement of the Problem:

 Dental caries are among the most common oral and dental diseases affecting adults and children. To prevent caries, either the factors that cause caries should be reduced or the host resistance should be increased. Several compounds, such as bioglass, chitosan, and silver diamine fluoride (SDF), can enhance enamel remineralization.

This study was conducted to investigate the effects of chitosan, bioglass, chitosan-bioglass, and SDF compounds on remineralizing primary enamel lesions.

In this in vitro study, seventy-two primary canine teeth were collected. The teeth were exposed to a demineralization solution for 72 hours to create primary caries lesions. The primary Vickers microhardness test (VMT) was conducted to measure the initial values. The samples were randomly divided into six groups (n=12): Group 1: bioglass-chitosan solution; Group 2: chitosan; Group 3: bioglass solution; Group 4: SDF; Group 5: remineralization solution; Group 6: distilled water. The solutions of Groups 1, 2, and 3 were applied to the samples for 7 days, while the SDF solution was applied only once. The samples were immersed in an artificial saliva solution, which was refreshed daily. After the treatment, the final Vickers microhardness test (VMT) values were recorded. The data were analyzed statistically using a two-way ANOVA and Tukey's test (p< 0.05).

The results indicated a statistically significant effect of remineralizing compounds on both pre-treatment and post-treatment microhardness (p< 0.0001). However, no significant difference in microhardness was observed between the groups studied (p= 0.225).

All the compounds utilized in this study demonstrated a significant remineralizing effect on enamel lesions caused by primary caries in primary teeth. The chitosan-bioglass and bioglass groups exhibited the highest levels of remineralization, respectively. However, the comparison between the groups yielded insignificant results due to the dispersion of the samples. Therefore, further studies with larger sample sizes are recommended.

In an ideal pulpotomy, the radicular pulp remains vital, healthy, and fully encased within an odontoblastic layer. Mineral trioxide aggregate (MTA) and bone morphogenetic proteins (BMPs) have been suggested to facilitate this outcome. We aimed to compare the clinical and radiographic failure and success rates of MTA and rhBMP2 as pulpotomy medicaments.

Sixty-eight teeth from 3–6-year-old children were randomly assigned to two groups using a split-mouth design. Cervical pulpotomy was performed using MTA in one group and rhBMP2 in the other. Subsequently, the teeth were restored with stainless-steel crowns. Clinical and radiographic assessments were performed at 3, 6, 9, and 12-month follow-up intervals to evaluate success and failure rates. Data were analyzed using Chi-square test and Kaplan-Meier survival analysis (P<0.05)

At six and nine months, one tooth in the BMP2 group and one tooth in the MTA group showed internal resorption, respectively. After 12 months, one tooth in the BMP2 group exhibited PDL widening. The radiographic success rate was 100% for the MTA- and 97.1% for the BMP2-group at six months, 96.7% for both groups at nine months, and 96.7% and 93.3%, respectively, at 12 months. No clinical failure criteria were observed in any of the teeth. Survival analysis revealed no significant difference between the two groups.

The study reveals comparable outcomes between rhBMP2 and MTA, suggesting rhBMP2 as a viable alternative for pulpotomy in primary teeth. With minimal incidences of complications and no significant differences noted, rhBMP2 demonstrates potential for clinical use.

This study aimed to compare the antimicrobial efficacy of saline, 0.5% and 2% Zataria multiflora (Z. multiflora) essential oil, 0.5% and 2% Mentha piperita (M. piperita) essential oil, and 0.2% chlorhexidine (CHX) as root canal irrigants for primary molar teeth.

A total of 64 primary molars were used in this in vitro study. The teeth were randomly assigned to six groups (N=10). The root canals were prepared up to file #35, and all teeth were sterilized before contamination with Enterococcus faecalis (E. faecalis; ATCC 29212) suspension. After 48 hours of incubation, the root canals in each group were irrigated with the respective irrigants. Sterile paper points were then used to collect microbial samples from the root canals. A colony counter was used to count the number of colony-forming units (CFUs). Data were analyzed by SPSS version 20 (alpha=0.05).

The colony count was significantly different among the groups (P<0.001), and 2% M. piperita (P=0.009), 0.5% Z. multiflora (P=0.021), and 0.2% CHX (P=0.002) were significantly more effective than saline in elimination of E. faecalis. The ascending order of microbial count after irrigation was as follows: saline > 0.5% M. piperita > 0.2% CHX > 2% M. piperita > 0.5% Z. multiflora.

The current study showed the optimal antibacterial activity of 0.5% Z. multiflora essential oil and 2% M. piperita essential oil against E. faecalis, and indicated their possible efficacy for use as an irrigant for root canal irrigation of primary molars.

The use of fiber posts in endodontically treated primary maxillary central incisors improves the retention of composite resin restorations. The purpose of this study was to evaluate the effect of 4 different luting cements on fracture resistance of primary maxillary central incisors with fiber posts.

In this in vitro study, 40 primary maxillary central incisors were endodontically treated and obturated with Metapex. They were then randomly divided into four groups (n=10) for cementation of fiber posts with GC Fuji I glass ionomer luting cement, Panavia F2.0 dual-cure luting cement, Panavia SA Luting Plus cement (self-adhesive), and TotalCem self-adhesive cement. After 1000 thermal cycles, the fracture resistance was measured. Data were statistically analyzed using ANOVA (alpha=0.05).

The mean fracture resistance was 267.07±130.01N in TotalCem, 257.27±102.56N in Panavia F2.0 dual-cure cement, 227.82±110.40N in Panavia SA Luting Plus self-adhesive cement, and 220.89±59.96N in GC Fuji I glass ionomer group. There was no statistically significant difference in fracture resistance among the four groups (P=0.714).  

Type of luting cement had no significant effect on fracture resistance of primary maxillary central incisors with fiber posts. Nonetheless, TotalCem yielded the highest fracture resistance. Considering its self-adhesive property and easy workability, it can be a good option for cementation of fiber posts in endodontically treated primary central incisors.

The demand for an ideal root canal filling material in primary teeth with maximum antibacterial properties keeps escalating to improve the success rate of root canal treatment in primary teeth. Hence, the present study was conducted to determine the antimicrobial efficacy of the different concentrations of a novel root canal filling material.

An in vitro study was designed to compare the antimicrobial efficacy of different concentrations of the novel obturating material for primary teeth. Different concentrations of the novel obturating material were prepared using calcium hydroxide, zinc oxide cement, and metronidazole and were tested for its antimicrobial efficacy against Streptococcus mutans and Enterococcus faecalis using Mueller–Hinton Agar for 24 h at 37°C. The zone of inhibition was measured in millimeters after 24 h. The values were entered into a Microsoft Excel spreadsheet and subjected to statistical analysis. Descriptive statistics were used for data summarization and presentation. Friedman test and Kruskal–Wallis test were used to compare the different concentrations of the novel obturating materials against S.mutans and E.faecalis. P < 0.05 was considered to be significant.

Against S. mutans at 1% concentration, the zone of inhibition was statistically greater at 50 μl and at 2% and 3%, the zone of inhibition was greater at 100 μl. Similarly, against E. faecalis, the zone of inhibition was statistically greater at 100 μl at 2% and no significant difference was noted at 1% and 3%. Comparison between the groups at 25, 50, and 100 μl shows no significant difference against S. mutans between 1%, 2%, and 3% of 60–40 concentration. However, 3% 60–40 concentration at 50 μl shows significantly increased zone of inhibition against E. faecalis.

Two percentage metronidazole at 60–40 (calcium hydroxide–zinc oxide) concentration of the novel obturating material at 100 μl has better antibacterial properties against both S.mutans and E. faecalis.

Conservative treatment of adhesive dentistry considers demineralized dentin as a bonding substrate, and utilizing silver diamine fluoride (SDF) on demineralized dentin before composite restoration, probably can be beneficial. To evaluate the effect of SDF and potassium iodide (KI) on nano leakage plus the micro tensile bond strength of composite to demineralized dentin in primary teeth.

In this experimental- laboratory study, seventy-eight teeth in the micro tensile group and ninety teeth in the nano leakage group were divided into two groups with sound and demineralized dentin. Each group of teeth was divided into three separate groups. In the first group, bonding was used without pre-treatment. In the second group, the SDF was used before the bonding agent and SDF and, KI was used in the third group. Two-way ANOVA, Bonferroni's post hoc test, Mann-Whitney test and Fisher's exact test were used for data analysis. (α<0.05)

The lowest mean bond strength was in the SDF and KI groups in both sound (10.0 ± 1.9) and demineralized (6.8 ± 2.3) dentin groups. Using KI significantly reduced bond strength (P <0.05). Nano leakage in teeth with sound and demineralized dentin in both SDF and SDF and KI groups was significantly lower than in the control groups (P <0.05).  

Using SDF does not harm composite bond strength to primary teeth, but using KI after SDF reduces composite bond strength. The use of SDF and KI significantly reduces composite nano leakage.

To compare the effectiveness of fluoride varnish and two calcium-based fluoride products on the remineralization of primary teeth enamel.

Surface-microhardness (SMH) of 36 extracted anterior primary teeth was measured by Vickers test (50gr/5 seconds) to provide a baseline for later comparisons. All teeth were immersed in demineralizing solution for 96 hours to create caries-like lesions and SMH was determined for the artificially-induced caries. The teeth were randomly assigned to three groups consisting of 5% fluoride varnish once daily/10 seconds, Clinpro™ 5000 toothpaste once daily/2 minutes, and Remin Pro cream once daily/3 minutes for 28 days. All specimens were kept in artificial saliva with pH cycling during the study period. After remineralization, SMH was evaluated for the last time. Data were analyzed by one-way ANOVA, Mauchly's sphericity, and RM-ANOVA with Bonferroni correction for inter-and- intra-group comparisons at the three stages of the study.

Neither the baseline SMH nor the SMH of the artificially created caries showed significant differences among the samples (P>0.05). The post-treatment SMH was highest in the Clinpro group (296.4±73.1kgf/mm2), followed by Remin Pro (283.8±119.3kgf/mm2), and varnish (270.9±78.3 kgf/mm2). There was no significant difference among the groups after treatment (P>0.05). We also did not observe a significant difference among the three different study stages (P>0.05).

Within the limitations of this in-vitro study, daily application of low fluoride-calcium compound seems to be as effective as the professional use of fluoride varnish or high-content fluoride toothpaste in remineralizing initial caries of primary teeth.

Statement of the Problem:

 The dilemma of microleakage at the composite-tooth interface is still a major challenge in operative dental practice.

This study aimed to compare the microleakage of universal adhesive with self-etch and total-etch bonding strategies for restoration of class-II primary molar cavities.

This in vitro, experimental study was conducted on 75 extracted primary molars. Class-II cavities were prepared in mesial or distal surfaces. The teeth were randomly divided into five groups of Adper Single Bond 2 (3M ESPE; St Paul, MN, USA), Clearfil SE Bond (Kuraray Noritake, Osaka, Japan), G-Bond (GC Corp., Tokyo, Japan), G-Premio Bond (GC Corp., Tokyo, Japan) with total-etch mode and G-Premio Bond with self-etch mode. Cavities were also restored with Nano-hybrid resin composite (Grandio, VOCO, Cuxhaven, Germany) and incubated for 24 hours, followed by thermocycling at 1500× between 5-55°C within a dwell time of 20 seconds. Later, the cavities were placed in 1M silver nitrate solution and evaluated under a stereomicroscope. Finally, microleakage was assessed quantitatively and qualitatively. One tooth in each group was prepared and evaluated under a scanning electron microscope (SEM). Data were analyzed using One-way ANOVA, Tukey's post hoc test and Chi-square test (p< 0.05).

The microleakage values were significantly different in the study groups (p< 0.05). The highest level of microleakage was noted in G-Bond and the lowest in G-Premio Bond with total etching. There was a significant correlation between the qualitative and quantitative measurements of microleakage.

The G-Premio Bond yielded acceptable results in terms of microleakage in total-etch and self-etch modes. However, additional etching is recommended to improve the quality of bonding.

 Different root canal filling materials show different clinical and radiographic success rates. Since there is controversy on the best root canal filling material in primary dentition, the aim of this study was to summarize information about root canal filling materials for primary teeth in terms of biocompatibility, cytotoxicity, resorption rate, and survival rate.

 By searching online databases, studies that addressed biocompatibility, cytotoxicity, resorption, and survival rates of different root filling materials in primary teeth from 1985 to 2020 were evaluated and the required data were extracted. The results were tabulated and compared.

 Due to methodological discrepancies, different studies show different and sometimes inconsistent results, which make it hard to reach a final conclusion; but it seems that Vitapex and Maisto's paste are more biocompatible and have a good survival rate. Zinc oxide eugenol (ZOE) and calcium hydroxide have lower cytotoxicity among different filling materials. However, due to low resorption rate, ZOE can affect permanent successors.

 Based on the unique characteristics of each patient, different filling materials may be used for a clinically optimal dental treatment.

Stainless steel crowns (SSCs) are the gold standard for restoration of severely damaged primary teeth. However, the unesthetic appearance of SSCs is responsible for their lower acceptance by clinicians and patients. Zirconia crowns are another option for reconstruction of severely damaged teeth, which also provide optimal esthetics.

Our patient was a 5-year-old child with a carious primary mandibular first molar. A prefabricated zirconia crown was considered for the tooth because the parents disapproved the color of SSC. The computer-aided design/computer-aided manufacturing (CAD/CAM) technology was used to fabricate a zirconia crown with porcelain veneering since the size of prefabricated crowns did not match the size of the respective tooth.

At the 1-year follow-up, the crown fabricated with this technique showed optimal esthetics, function, and durability. Although these crowns have shortcomings such as the risk of porcelain chipping, and require greater tooth preparation than SSCs, they can serve as a suitable alternative for reconstruction of severely damaged primary teeth when esthetics is an important parameter to consider.

The purpose of this study was to systematically review the literature and use meta-analysis to investigate whether chlorhexidine (CHX) application after acid etching as an adjunct treatment has any influence on the immediate and delayed bond strength to primary dentin.

In this review, PubMed, ISI (all data bases), Scopus and Cochrane were searched according to the selected keywords up to April 30, 2018. The full texts of all published articles that met our primary inclusion criteria were obtained. The studies were analyzed in two parts: in vitro studies that evaluated the effect of CHX application during the bonding procedures (application after acid etching) on immediate and delay dentin bond strength of resin-dentin interface.

The initial search yielded 214 publications, of which 8 were selected after thorough methodological assessment. None of the clinical studies fulfilled the eligibility criteria. Our results indicated that in comparison to the control group, CHX significantly reduced immediate resin-dentin bond strength (P=0.043). These values were increased after aging (P<0.001).

Based on this invitro Meta-analysis CHX application, improve resindentin bond strength durability in primary teeth.

Considering the high prevalence of consumption of iron drops, and the resultant reduction in microhardness of primary enamel, this in vitro study aimed to assess the effects of Sucrosomial® iron and iron drop diluted with natural fruit juice on microhardness of primary enamel.

This in vitro, experimental study evaluated 45 extracted sound primary anterior teeth, that were randomly assigned to three groups (n=15) of Sideral, Irofant, and Irofant + natural apple juice. The titratable acidity and pH of solutions were measured. After measuring the baseline microhardness by a Vickers hardness tester, the teeth in the three groups were exposed to the respective iron drop solutions at 37°C for 5 minutes. They were then rinsed with distilled water, and their secondary microhardness was measured. Data were analyzed using the dependent Student t-test, ANOVA, and ANCOVA (alpha=0.05).

Irofant had the lowest pH and the highest titratable acidity among the tested solutions. A reduction in enamel microhardness occurred in all groups after exposure to iron drops (P=0.0001). The reduction in microhardness was significantly greater in Irofant group compared with Irofant + natural apple juice (P=0.0001). Also, the reduction in microhardness was significantly greater in Irofant + natural apple juice compared with Sideral iron drop group (P=0.0001).

Sideral iron drop with Sucrosomial iron has minimal adverse effect on microhardness of primary enamel. Also, dilution of iron drops with natural apple juice can be suggested as an effective strategy to decrease their adverse effects on microhardness of primary enamel.

Early loss of deciduous teeth has negative effects on chewing function, aesthetics, self-esteem and permanent dentition. This study aimed to evaluate the prevalence of premature primary tooth loss and the contributing factors in children aged 36 -71 months in Babol city (North of Iran). In this cross-sectional study, 558 heathy preschool children underwent oral examination to record the type and frequency of premature tooth loss and Silness-Loe plaque index. The parents were then asked to fill out a questionnaire about the related factors. Data were evaluated by SPSS (v23) and were analyzed using one-way ANOVA and independent-samples t-test and multiple linear regression analysis. The level of significance was set at p ≤ 0.05. The frequency rate of missing primary teeth was 1.56% estimated in 13.62% of children. The mean number of missing teeth showed a significant difference among different subgroups of children classified based on parent’s education (p=0.001), socio-economic status (p=0.001), child's age (p=0.02), plaque index (p=0.001), frequency of consumption of cariogenic snacks (p=0.001) and brushing (p=0.001). According to multiple linear regression test, Father's educational level, socio-economic status, plaque index, and frequency of consumption of cariogenic snacks were correlated with the number of missing teeth. Less than one-seventh of children had at least one premature missing primary tooth. Child's age, parent’s educational level, socio-economic status, frequency of consumption of cariogenic snacks, plaque index and brushing are related to premature primary tooth loss.

Achieving durable restorations with adequate strength in severely damaged primary anterior teeth in children is a priority. The aim of this study was to investigate the effect of dentin pretreatment with chlorhexidine on push-out bond strength of composite restorations.

In this in vitro experimental study, 56 extracted primary anterior teeth were randomly divided into 4 groups: (1) saline and total-etch bonding agent, (2) chlorhexidine and total-etch bonding agent, (3) saline and self-etch bonding agent, and (4) chlorhexidine and self-etch bonding agent. After the application of bonding agents, the post space was filled with Z250 composite resin. Following thermocycling of the samples, the push-out test was performed using a universal testing machine, and the results were analyzed with two-way ANOVA.

The mean push-out bond strength values in groups 1 to 4 were 5.7, 8.39, 5.35, and 7 MPa, respectively. Chlorhexidine groups had significant differences with saline groups in bond strength (P<0.05) but there was no statistically significant difference between the self-etch and total-etch bonding agents in the groups (P>0.05).

Both types of bonding agents (self-etch and total-etch) exhibited favorable results in radicular dentin of primary anterior teeth; however, pre-treatment with chlorhexidine increased the push-out bond strength of composite restorations in primary anterior teeth.

Dental traumatic injuries most commonly occur in the primary and mixed dentition, but vertical complicated crown-root fractures are rarely seen in children. Clinical and radiographic examination of these injuries helps in accurate diagnosis and management. According to the International Association of Dental Traumatology guidelines, treatment usually involves extraction followed by placement of a space maintainer. Cases of complicated crown and root fracture in primary posterior teeth are often unnoticed by the clinician, at the time of injury. Two such patients are presented, who reported symptoms a few weeks after their accident. They were managed conservatively by initial stabilization with stainless steel crowns, followed by root canal therapy. This report highlights the need for referral to specialists and emphasizes the importance of conservative management of primary teeth to maintain functional demands.

This study was conducted to investigate root canal overfilling with different material placement techniques in primary teeth.

A systematic search was undertaken by searching Pubmed/MEDLINE and Scopus for English language peer-reviewed articles published until February 2018 that reported overfilling of primary tooth pulpectomy. Two reviewers independently screened and identified studies against the selection criteria and independently collected the data using a specially designed data extraction form. Overfilling rate was the primary summary measure. The weighted pooled overfilling rates were estimated by random-effects meta-analysis.

Twenty clinical and 4 in-vitro studies satisfied the eligibility criteria. In the clinical studies, the pooled overfilling rate for Zinc-Oxide Eugenol was 23.3% with Lentulo mounted in handpiece, 22.7% with Lentulo, and 17% with plugger techniques. The pooled overfilling rate for Calcium hydroxide-based materials was 16.7% with Lentulo mounted in handpiece, 14.7% with Lentulo, 19.6% with provided syringe, and 25.7% with plugger techniques. In the in-vitro studies, neither individual overfilling rates nor two by two comparisons were subjected to meta-analysis because of the inadequate number of studies.

The lowest overfilling rate in the clinical studies was with plugger and hand-held Lentulo techniques for ZOE and calcium hydroxide-based materials, respectively.

Objectives :

The main disadvantage of composite resins is their polymerization shrinkage, which can lead to microleakage. The purpose of this in vitro study was to evaluate the microleakage of bulk fill and conventional composites and a new hybrid glass ionomer (GI) in class II restorations of primary molar teeth.

Methods :

In this in vitro study, 51 primary molar teeth were randomly divided into three groups. Standard class II cavities were then prepared. In group 1 the cavities were restored with Filtek bulk fill composite; in group 2, the cavities were incrementally filled with Z250 conventional composite and in group 3, EQUIA Forte hybrid GI resin was used to fill the cavities. The teeth were subjected to thermal and then mechanical thermocycling. Afterwards, the teeth were immersed in 1% methylene blue solution. The teeth were then mesiodistally sectioned, and microleakage was evaluated at the occlusal and gingival margins under a stereomicroscope and a scanning electron microscope (SEM). The Shapiro-Wilk and Kruskal-Wallis tests were used to statistically analyze the data.

Results:

 There was no statistically significant difference in the mean microleakage of bulk fill and conventional composites and hybrid GI in the occlusal (P=0.495) or gingival (P=0.293) margins. The gingival microleakage was significantly higher than occlusal microleakage in all three groups (P<0.05).

Conclusion:

 Based on the results of the present study, microleakage of Filtek bulk fill composite is the same as that of Z250 conventional composite and EQUIA Forte hybrid GI.