Efficacy of non-instrumental Endodontic treatment in primary teeth: a systematic review of clinical randomized trials

BACKGROUND

Endodontic therapy in pediatric dentistry is a challenging procedure, especially for special needs, uncooperative, and very young patients. A new conservative approach which is the non-instrumental endodontic treatment (NIET) has been developed to simplify the management of primary teeth requiring pulpectomy. This review aimed to compare the efficiency of NIET and conventional endodontic treatment in primary teeth.

METHODS

Electronic databases including MEDLINE (via PubMed), Cochrane Library (CENTRAL), and Scopus without restrictions on publication year or publication language were searched. Only randomized clinical trials reporting clinical and radiographical outcomes of NIET and conventional pulpectomy on primary teeth were considered eligible. Two reviewers extracted the data according to the PRISMA statement and assessed the bias risk using the revised Cochrane risk-of-bias tool and a meta-analysis was performed.

RESULTS

From 3322 screened articles, seven articles meeting the inclusion criteria were included. The selected studies included 283 primary molars, of 213 children aged between 3 and 9 years, treated by NIET and conventional pulpectomy, and had follow-up periods ranging from 1 month to tooth exfoliation. Two studies reported good success rates for both the NIET technique and endodontic therapy with no statistically significant difference while three studies showed radiographical significant differences with a low success rate for the NIET technique. Only one study reported better outcomes in the pulpectomy group with statistically significant differences. The quantitative grouping of the included studies showed no significant differences between NIET and conventional endodontic therapy regarding clinical and radiographical success (p value > 0.05).

CONCLUSION

No difference between the NIET technique and the conventional endodontic therapy in primary molars requiring pulpectomy could be confirmed. Results of the present review need to be interpreted with caution since the quality of evidence according to the GRADE was considered as moderate to very low. Therefore, additional clinical trials on the NIET technique are recommended.

Influence of silver fluoride plus potassium iodine on adhesive properties of primary carious dentin-resin interface: An in vitro study

This paper evaluated the influence of different protocols of silver fluoride (SF) pretreatment of artificial carious lesions on the adhesive interface of composite resin restorations and remineralization of deciduous dentin compared to silver diamine fluoride (SDF). Sixty-four deciduous molar teeth were randomly divided into 8 groups (n = 8) according to the restoration time (immediately - IM; 30 days after SDF/SF treatment - 30 D) and treatment before restoration (SDF 38 %; SDF 38 % + potassium iodide - KI; SF 38 %; SF 38 % +KI). After SDF/SF application, teeth in the IM group were restored with self-etch universal adhesive system/composite resin. Samples in the 30D groups were stored in artificial saliva (37 °C) for 30 days before receiving the same restoring protocol. Beams were obtained from all groups and subjected to bond strength tests (µTBS), ultrastructural qualitative analysis (FEG) and mineral analysis (SEM/EDX; Micro-Raman spectroscopy). The µTBS data were subjected to three-factor ANOVA and multiple comparisons (Holm-Sidak method). Bond strength values (MPa) for IM groups were 16.9 ± 2.7 (SDF); 17.6 ± 3.5 (SDF + KI); 16.8 ± 5.5 (SF); 18.4 ± 4.1 (SF + KI); and 14.9 ± 4.2 (SDF); 16.0 ± 5.4 (SDF + KI); 14.1 ± 3.6(SF); 16.4 ± 5.4 (SF + KI) for 30D groups. Bond strength wasn't influenced by the moment of restoration (IM or 30D); the use of KI didn't alter adhesion characteristics; SDF/SF solutions resulted in similar adhesive strength; calcium and phosphate expressions were identified at the interfaces on IM and 30D moments. However, 30D presented qualitative increase in these ions, compatible with remineralization. It was concluded that the adhesion of composite resin restorations in artificial caries lesions of deciduous teeth treated with SDF (38 %) and SF (38 %) had similar effects in vitro; the use of KI or the moment when restorations were accomplished did not influence the adhesion and all tested protocols promoted remineralization of carious dentin.

Parents' acceptance of minimal intervention procedures for dental caries management in children: a scoping review

PURPOSE

In recent years, minimal intervention procedures (MIPs) for treating dental caries in children have stood out as an innovative method. Nevertheless, the treatment decision should be based on scientific evidence, professional expertise, and parents' preference/acceptance. Evaluating the acceptance of MIPs by parents is an essential factor, but little information is available on what guides this preference.

METHODS

This scoping review aims to synthesize the evidence on parents'/caregivers' acceptance of MIP for managing cavitated caries lesions in children. A search was performed in the PubMed, Cochrane Library, Lilacs and Google Scholar databases with no restriction on date or language.

RESULTS

A total of 19 articles were selected (6 clinical trials, 1 longitudinal and 12 cross-sectional studies). The application of silver diamino fluoride (SDF) was the most commonly evaluated procedure (n = 17), followed by the atraumatic restorative technique (ART) and the Hall Technique (HT). The acceptance of MIPs ranged from 1.4% to 100%, and the application of SDF was better accepted in posterior teeth and in uncooperative children. ART had better aesthetic acceptance than HT.

CONCLUSION

Application of SDF, Hall Technique and ART was well accepted by parents/caregivers. However, a gap remains in the literature regarding the acceptance of other procedures. Therefore, further studies in this area will contribute toward a better understanding of the opinion of parents/caregivers, and thus improve caries lesion management in children.

Volumetric Analysis of Various Pediatric Rotary Files in the Preparation of Primary Root Canals Using Cone-beam Computed Tomography

Aim

This study was planned to evaluate and compare the cleaning efficacy of three pediatric rotary files with the standard Protaper adult file system in primary teeth using cone-beam computed tomography (CBCT).

Materials and methods

A total of 40 extracted deciduous second molars, with palatal/mesial roots having at least two-thirds of root length and an intact furcation area, were distributed randomly among four groups, with each group containing 10 teeth. Canal preparation of group I (Pro AF Baby Gold), group II (Kedo SG Blue), group III (Prime Pedo), and group IV (Protaper) was done. Pre- and postoperative CBCT images were taken. The volumetric changes of the root canals were assessed and subjected to statistical analysis using Statistical Package for the Social Sciences (SPSS) version 16 and R Studio 3.1.1. Volumetric changes within the groups were analyzed using paired t-tests and between the groups using analysis of variance (ANOVA).

Results

The comparison of mean volume difference between groups using ANOVA was statistically significant with F = 4.467, p = 0.002. A Tukey post hoc test revealed that group IV was statistically significant compared with groups I (p = 0.033) and III (p = 0.008) but was not statistically significant with group II (p = 0.170). There was no statistically significant difference in volumetric changes within the three pediatric rotary file systems.

Conclusion

Protaper removed more dentin than all the pediatric rotary files, but it was not statistically significant over Kedo SG Blue. Among the pediatric rotary files, Kedo SG Blue removed more dentin than Pro AF Baby Gold and Prime Pedo, but they were not statistically significant.

How to cite this article

Nainer Chidambaram JV, Jayaprakash J, Arangannal P. Volumetric Analysis of Various Pediatric Rotary Files in the Preparation of Primary Root Canals Using Cone-beam Computed Tomography. Int J Clin Pediatr Dent 2024;17(1):15-20.

Effects of topical fluoride on primary tooth enamel microhardness after diode laser treatment

Objectives

Tooth decay is controlled and prevented using fluorides. Specifically, a combination of laser irradiation and topical fluoride application can improve fluoride absorption. Although laser irradiation is recommended in traditional technology for caries prevention, little is known about the efficacy of caries-inhibiting laser diodes. Further, most studies have focused on permanent teeth. The objective of this study was to explore the effect of laser diode radiation mixed with topical fluoride on the enamel surface microhardness of primary teeth.

Material and method

The 60 primary teeth were divided into 60 plates. Baseline Vickers microhardness was established for each enamel surface. The samples were then divided into three groups. 4 % NaF varnish (group A) and 4 % NaF varnish using diode 2 and 3 W lasers (groups B and C, respectively). The final microhardness was measured and statistically evaluated using SPSS version 16. ANOVA was used to compare the means of the tested groups, which had a P-value of 0.05, indicating significance.

Result

The mean and standard deviation of microhardness for the different groups was tested. Group C (4 % NaF with a diode laser at 3 W) showed a higher average Vickers hardness (VHN) than Group B (4 % NaF with a diode laser at 2 W), whereas group A showed the lowest average VHN. There was a significant difference in microhardness between groups (P 0.05).

Conclusion

This study explored the effect of laser mixed with topical fluoride on enamel surface microhardness of primary teeth. The use of a diode laser (Quanta System, Italy) with a fluoride varnish applied to the enamel surface has a greater effect on the resistance of the enamel to caries.

Fluke of Fusion and Concrescence in Maxillary Deciduous Incisors: A Case Report

Aim

The aim of this paper is to report a rare case in a 6-year-old girl where two dental anomalies, fusion and concrescence, coexisted in primary dentition. This highlights the significance of the accurate early diagnosis of these dental anomalies.

Background

Odontogenic anomalies are frequently encountered in dental practice. These anomalies can occur due to abnormalities during the differentiation stage and may lead to aberrations in hard tissue formation. Some of the uncommon and unusual dental anomalies of number and form include fusion, gemination, and concrescence.

Case description

This elusive case represents the fusion and concrescence together between the left central and a supernumerary tooth. The left primary central incisor presens as a large tooth with a groove through the incisal edge. Clinical observation along with radiographic evaluation using RVG radiographs and orthopantomogram (OPG) were used to arrive at a diagnosis.

Conclusion

Early diagnosis of concrescence will reduce the risk of possible complications associated with any need for extraction later on. Monitoring the patient and long-term follow-up are required to manage the case with coexisting anomalies of true fusion and acquired concrescence.

Clinical significance

A thorough history-taking and clinical and radiographic evaluation of fusion and concrescence at an early stage results in an accurate diagnosis. A careful monitoring plan is a key to reduce the risk of possible complications later on.

How to cite this article

Ahuja V, Pathak A. Fluke of Fusion and Concrescence in Maxillary Deciduous Incisors: A Case Report. Int J Clin Pediatr Dent 2023;16(S-3):S327-S330.

Non-native and native tree species plantations and seasonality could have substantial impacts on the diversity of indigenous soil fauna in a semi-arid forest ecosystem

The temporal and spatial dynamics of soil fauna in many terrestrial ecosystems are still not fully understood, while soil fauna is one of the most critical characteristics in assessing soil quality. Therefore, the effects of native [Quercus brantii (QP) and Amygdalus scoparia (AMP)] and non-native [Cupressus arizonica (CUP) and Pinus eldarica (PIN)] plantations and natural trees [Quercus brantii coppice trees (QNC), standard (QNS), and Amygdalus scoparia (AMN)] on diversity and abundance of macro- and mesofauna were done in the semi-arid forest of Zagros, Iran. Samples were collected beneath the canopy of woody species and the outer edge of the canopy in spring and summer seasons. For this purpose, soil samples [(7 samples per woody species + control) × 2 seasons × 3 replicates] were taken from 0 to 20 cm depths. Each soil sample was a mix of three soil cores. For the macrofauna, 15 species belonging to four families (in spring) and 17 species in nine families (in summer) were collected and identified. For the soil mesofauna, 14 species belonging to 14 families (in spring) and 13 species in 13 different families (in summer) were identified, respectively. The fauna diversity indices under the canopy of studied species were higher in summer season than in spring. The result showed that the macrofauna diversity was affected by tree species, while mesofauna was affected by seasonal changes. Macrofauna biodiversity was higher under the canopy of PIN and CUP than other trees. Principle component analysis showed that the diversity of the macrofauna was higher under the canopy of PIN and CUP, and influenced by soil characteristic properties, soil properties did not influence them. Yet the diversity of the mesofauna was affected by soil characteristics and was higher in areas with higher organic carbon, nitrogen, substrate-induced respiration, basal respiration, microbial carbon biomass, and alkaline phosphatase. In addition, mesofauna biodiversity had a significant positive correlation with the soil quality index (SQI). SQI was higher under the canopy of natural stands, especially the QNS. Conservation of native species (QNS, QNC, and AMN) and plantation with native deciduous species (QP and AMP) seem to moderate environmental conditions and increase soil macro- and mesofauna diversity and SQI.

Cone-beam computed tomography assessment of the root canal morphology of primary molars

BACKGROUND

This study aimed to assess the root canal morphology of primary molars using cone-beam computed tomography (CBCT).

METHODS

This cross-sectional study evaluated 60 maxillary and mandibular primary first and second molars on CBCT scans of patients retrieved from the archives of Hamadan School of Dentistry between 2018-2020. The teeth were evaluated regarding the number of roots and canals, canal type according to the Vertucci's classification, and root surface concavities. Data were analyzed descriptively and by independent t-test.

RESULTS

The most frequent number of canals and roots in the maxillary right and left first molars was 3 canals (60%) and 3 roots (80%). These values were 4 canals (80%) and 5 canals (50%) with 3 roots in the maxillary right and left second molars, respectively, 4 canals (100%) and 2 roots (50%), and 3 canals (60%) and 2 roots (50%) in mandibular right and left first molars, respectively, and 4 canals (92.3%) and 3 roots (61.5%) in mandibular right and left second molars. Vertucci's type IV was the most common canal type in mesial and distal canals, type I was the most common in mesiobuccal, mesiolingual, distobuccal, and distolingual, and types I and II were the most common in the palatal canal. The maximum and minimum concavities were noted in the buccal (26.7%) and mesial (8.3%) surfaces, respectively.

CONCLUSIONS

A wide variation exists in the number of roots and canals of maxillary and mandibular primary molars, which calls for further attention in treatment of such teeth.

Er:YAG laser in selective caries removal and dentin treatment with chitosan: a randomized clinical trial in primary molars

This study evaluated the effect of chitosan on dentin treatment after selective removal of caries lesions with Er:YAG laser in reducing Streptococcus mutans, as well as its effect on the performed restorations. The sample consisted of children (aged 7 to 9 years) with active carious lesions and dentin cavitation located on the occlusal surface of deciduous molars. Eighty teeth were randomly distributed into 4 groups according to the caries removal method: Er:YAG laser (250 mJ/4 Hz) or bur and dentin surface treatment: 2.5% chitosan solution or distilled water. The bacterial load of caries-affected dentin was quantified by counting CFU/mg (n = 10). The teeth were restored and evaluated at 7 days, 6 months, and 12 months using modified USPHS criteria (n = 20). Microbiological data was analyzed by Mann-Whitney and clinical analyses were done using Kruskal-Wallis and Dunn test (α = 0.05). The results showed that the Er:YAG laser significantly reduced the amount of Streptococcus mutans (p = 0.0068). After dentin treatment with chitosan, there was a significant reduction in the amount of Streptococcus mutans for both removal methods (p = 0.0424). For the retention and secondary caries criteria, no significant differences were observed along the evaluated time (p > 0.05). The laser-treated group was rated "bravo" for discoloration (p = 0.0089) and marginal adaptation (p = 0.0003) after 6 and 12 months compared to baseline. The Er:YAG laser reduced the amount of Streptococcus mutans and the chitosan showed an additional antibacterial effect. After 1 year, the Er:YAG laser-prepared teeth, regardless of the dentin treatment, showed greater discoloration and marginal adaptation of the restorations.

Clinical manifestations of tooth eruption in the first year of life and related risk factors in three regions of Brazil: multicenter birth cohort study

PURPOSE

Estimate the incidence of teething symptoms and investigate risk factors at three centers in different regions of Brazil.

METHODS

A prospective cohort study enrolled children at birth in the cities of Manaus (northern region), Porto Alegre (southern region) and Salvador (northeast region). Sociodemographic and anthropometric variables were collected at baseline and 6 months. At 12 months, data were collected on the child's health through structured interviews and dental examinations, including the primary outcome: occurrence of signs and symptoms of tooth eruption reported by parents. Statistical analysis involved Poisson regression with robust variance, with calculation of relative risks (RR).

RESULTS

The incidence of teething symptoms was 82.4% (238/289). The multivariate analysis revealed a higher occurrence of the outcome in the city of Salvador (RR = 1.39; 95% CI 1.23-1.58), when mother's education was more than 11 years (RR = 1.31; 95% CI 1.04-1.65), when a larger number of individuals resided in the home (RR = 1.15; 95% CI 1.02-1.29), when a smoker resided in the home (RR = 1.16; 95% CI 1.03-1.31) and when the child presented flu or cold in the first year of life (RR = 1.23; 95% CI 1.09-1.38). The most reported symptoms were fever (50.5%), irritability (42.6%), itching (40.8%) and diarrhea (35.3%). Most parents (82%) took some action to alleviate symptoms, including unprescribed systemic medication, such as analgesic, anti-inflammatory and anti-diarrheic agents.

CONCLUSION

Reports of teething symptoms were associated with the city investigated, socioeconomic factors of the families and characteristics of the child's health. A high rate of administering unprescribed medication was also found.

Evaluation of the efficacy of the use of violet LED light in the bleaching of damaged primary incisors darkened by trauma

BACKGROUND

The aim of this study was to evaluate efficacy of violet LED light for the bleaching treatment of primary incisors darkened by trauma.

METHODS

Twenty deciduous incisors with color change were selected, divided into two groups: control - no bleaching protocol was applied, and VL- treated with violet LED. The change color analysis was taken in each tooth, by spectrophotometer. In three different time: baseline - before treatment, after 4 treatment sessions and after 8 treatment sessions.

RESULTS

The color change data were analyzed using ANOVA and a post- hoc Tukey tests (α=0.05). After 4 and 8 sessions no differences were observed between the groups (p<0.05).

CONCLUSIONS

Thus, it can be concluded that violet LED light was not effective in bleaching primary incisors darkened by trauma after 8 sessions.

In vitro antibacterial effects of photodynamic therapy against Enterococcus faecalis in root canals of deciduous teeth

OBJECTIVE

This study aimed at evaluating the in vitro antibacterial efficacy of photodynamic therapy (PDT) on planktonic E. faecalis and its biofilm in the root canal of infected deciduous teeth.

METHODS

Forty root canals of maxillary deciduous anterior teeth were enlarged up to #35 K-file and inoculated with E. faecalis for 21 days. The root canals were randomly assigned into four groups (n = 10): The normal saline group (control), 1% NaClO group, PDT group, and the 1% NaClO + PDT group. Paper point samples were obtained at baseline (S1) and after treatment (S2). The colony-forming units (CFU) were counted, and the bacterial growth rate calculated. From each subgroup, 5 samples were randomly selected after treatment and a scanning laser confocal microscope (CLSM) used to determine the distribution of dead / living bacteria on the biofilm surface of each subgroup. A scanning electron microscope (SEM) was used to observe bacterial morphologies in the root canal walls of the remaining 5 samples in each subgroup. The Kruskal-Wallis test and Dunn test with boferroni adjustment were used to analyze the effect of the different treatment techniques on the E. faecalis in root canals.

RESULTS

Compared to the saline group, PDT significantly reduced bacterial counts in the root canal (p < 0.05). The CFU counts were lowest (p < 0.05) in the 1% NaClO and in 1% NaClO + PDT groups. The rate of bacterial death on the surface of the biofilm in the PDT group was significantly increased after treatment (p < 0.05), and the rate of bacterial death was highest in 1%NaClO group and 1%NaClO + PDT group (p < 0.05).

CONCLUSION

PDT has an antibacterial activity against E. faecalis in the root canal of deciduous teeth. Its activity against planktonic E. faecalis is better than the activity on the intact biofilm. The antibacterial activity of PDT on E. faecalis in root canals of deciduous teeth is lower compared to that of 1% NaClO.

Stem cells from human exfoliated deciduous teeth attenuate trigeminal neuralgia in rats by inhibiting endoplasmic reticulum stress

Background

The treatment of trigeminal neuralgia remains a challenging issue. Stem cells from human exfoliated deciduous teeth (SHED) provide optimized therapy for chronic pain. This study aimed to investigate the mechanisms underlying the attenuation of trigeminal neuralgia by SHED.

Methods

Trigeminal neuralgia was induced by chronic constriction injury of the infraorbital nerve. The mechanical threshold was assessed after model establishment and local SHED transplantation. Endoplasmic reticulum (ER) morphology and Caspase12 expression in trigeminal ganglion (TG) was evaluated as well. BiP expression was observed in PC12 cells induced by tunicamycin.

Results

The local transplantation of SHED could relieve trigeminal neuralgia in rats. Further, transmission electron microscopy revealed swelling of the ER in rats with trigeminal neuralgia. Moreover, SHED inhibited the tunicamycin-induced up-regulated expression of BiP mRNA and protein in vitro. Additionally, SHED decreased the up-regulated expression of Caspase12 mRNA and protein in the TG of rats caused by trigeminal neuralgia after chronic constriction injury of the infraorbital nerve mode.

Conclusions

This findings demonstrated that SHED could alleviate pain by relieving ER stress which provide potential basic evidence for clinical pain treatment.

Phylogeny and taxonomy of Erysiphe spp. on Rhododendron, with a special emphasis on North American species

The genus Rhododendron comprises over 1000 evergreen and deciduous species. In the Pacific Northwest Coast region of North America (PNWC), powdery mildews infecting deciduous Rhododendron spp. are well documented but less so on evergreen Rhododendron spp. Infections of both groups of hosts historically have been attributed to Erysiphe azaleae or E. vaccinii. No formal characterizations of powdery mildew fungi infecting either deciduous or evergreen Rhododendron spp. in the PNWC have been completed. The objectives of this study were to identify the powdery mildew pathogens infecting evergreen Rhododendron spp. in the PNWC and to assess the phylogenetic position of these fungi within the Erysiphaceae. To ascertain valid taxonomic conclusions, and to determine whether potential introductions of exotic Rhododendron powdery mildews in North America have occurred, it was necessary to put the new North American phylogenetic data into a worldwide context. Therefore, available phylogenetic data from all Erysiphe spp. on Rhododendron have been included in our analyses.Based on analyses of numerous new internal transcribed spacer (ITS) and 28S rDNA sequences and already available sequences deposited in GenBank retrieved from evergreen and deciduous Rhododendron spp., the following Erysiphe spp. could be phylogenetically confirmed (all belonging to Erysiphe sect. Microsphaera): Erysiphe azaleae nom. cons. (Oidium ericinum could be verified as a synonym), E. digitata (holotype sequenced), E. izuensis, and E. vaccinii. Erysiphe azaleae and E. vaccinii are epitypified with sequenced specimens, and an ex-neotype sequence has been obtained for Oidium ericinum. Erysiphe rhododendri (Erysiphe sect. Erysiphe), only known from two collections in India (Himalayan region), was not available for phylogentic analyses.

Does silver diammine fluoride concentration influence on bonding to carious dentinal lesions in primary teeth?

PURPOSE

This in vitro study evaluated the microshear bond strength (μSBS) of a universal adhesive after silver diammine fluoride (SDF) application at different concentrations on carious dentinal lesions in primary teeth.

METHODS

Flat dentin carious-induced surfaces from 40 primary molars were randomly assigned to four experimental groups: without SDF treatment (control), 12% SDF, 30% SDF, or 38% SDF application. After 14 days of storage in artificial saliva at 37 °C, a universal adhesive system (Scotchbond Universal, 3 M ESPE) was applied in the etch-and-rinse mode and resin composite cylinders were built (0.72 mm²). After 24 h of water storage, the μSBS test was performed and the failure mode was determined. Data were analysed using one-way ANOVA and Tukey's post hoc tests (α = 0.05).

RESULTS

The application of 38% SDF resulted in higher μSBS mean than control and use of 12% SDF (p = 0.006). No significant differences were observed among control, 12% SDF, and 30% SDF. All specimens tested showed adhesive/mixed failure.

CONCLUSION

The use of SDF does not jeopardise the bonding of a universal adhesive applied in the etch-and-rinse mode to carious dentinal lesions in primary teeth, irrespective of the product concentration.

Are electronic apex locators accurate in determining working length in primary teeth pulpectomies? A systematic review and meta-analysis of clinical studies

BACKGROUND

The lack of a well-defined apical constriction in primary teeth raises concerns regarding the accuracy of electronic apex locators (EALs) for measuring working length.

OBJECTIVES

To evaluate the accuracy of EALs in determining working length in primary teeth pulpectomies.

METHODS

Two reviewers searched ten databases up to September 2021. Clinical studies evaluating the accuracy of the electronic measurement of working length in primary teeth pulpectomies were included. Studies without a comparison group, with samples smaller than ten root canals, and that did not use a multiple frequency EAL were excluded. A meta-analysis was conducted to assess the paired differences in mean lengths between measurements obtained by electronic and comparative methods. In addition, a meta-analysis of proportion was applied according to the level of difference between the measures. The risk of bias and applicability of the studies were assessed using the QUADAS-2 tool. The certainty of evidence was assessed with the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach.

RESULTS

Twenty-nine studies were included in the qualitative analysis and twenty-three in the quantitative analysis. The methods of comparison for the electronic measurement were the radiographic method, radiovisiographic, scanning electron microscopy, and direct visualization. The meta-analysis showed that the electronic measurement tends to be shorter than radiographic measurement, while the other methods showed no difference. The proportion analysis showed a higher pooled proportion of difference values between electronic and comparative measurements within -0.5 to +0.5 mm (69.31%). The certainty of the evidence suggested very low confidence in estimating the outcome.

DISCUSSION

The results of this review denote a good performance of the EALs in determining working length in primary teeth pulpectomies. However, these results are based on clinical studies with low methodological quality and high heterogeneity, which require careful interpretation for clinical practice.

CONCLUSIONS

Although the results suggest acceptable accuracy of EALs in determining working length in primary teeth pulpectomies, the low quality of the included studies and the very low certainty of the evidence require clinicians to interpret these results with caution. More robust evidence is required to support that these devices are accurate for primary teeth.

Influence of tree species on selenium and iodine partitioning in an experimental forest ecosystem

Storage of selenium and iodine can greatly vary between forest ecosystems, but the influence of tree species on partitioning and recycling of those elements remains elusive. In this study, contents of Se and I were measured in tree compartments, litterfall, humus, and soil horizons in monospecific stands of Douglas fir, pine, spruce, beech, and oak under identical climatic and edaphic conditions. The cycle of each element was characterized in terms of stocks and fluxes. Lowest concentrations were in wood (Se: 8-13 μg kg^-1; I: <16.5 μg kg^-1). Senescing organs had higher Se and I content, than the living parts of trees due to direct exposure to atmospheric deposition, with some variation between coniferous and deciduous trees. For all stands, low amounts of Se and I were involved in biological cycle as reflected by low root uptake. In humus, the enrichment of elements greatly increased with the stage of organic matter (OM) degradation with average factors of 10 and 20 for Se and I. OM degradation and element persistence in humus was influenced by tree species. Deciduous trees, with low biomass, and fast degradation of OM stored less Se and I in humus compared to fir and spruce with high humus biomass. Interestingly, tree species did not affect soil reserves of Se and I. Concentration ranges were 331-690 μg Se kg^-1 and 4.3-14.5 mg I kg^-1. However, the divergent vertical profiles of the elements in the soil column indicated greater mobility of I. Selenium concentrations regularly decreased with depth in correlation with OM and Fe oxides content. For iodine, the maximum iodine concentration at a soil depth of 15 to 35 cm was caused by a parallel precipitation/sorption behavior of aluminium and organic iodine dissolved in the topsoil.

Traumatic injuries in primary dentition and their immediate and long-term consequences: a 10-year retrospective study from the State University of Rio de Janeiro, Brazil

BACKGROUND/AIM

Dental trauma is a highly prevalent problem worldwide. The aim of this study was to describe characteristics of trauma to anterior primary teeth and its sequelae for primary and successor teeth over a 10-year period of assistance at the paediatric dental traumatology clinic in the State University of Rio de Janeiro, Brazil.

MATERIALS AND METHODS

The data were obtained from the dental records of children assisted from 2006 to 2016. Inclusion criteria were trauma to anterior primary teeth; aged <1 to 9 years at the time of trauma; and at least one follow-up appointment. The data concerning traumatized teeth, child's age, soft tissue injuries, types of traumatic dental injuries and sequelae in both dentitions were collected.

RESULTS

Of the 1230 dental records, 483 (39.3%) were eligible, consisting of 815 teeth. The mean age at the time of trauma was 37.4 months (239 males and 244 females). The most important characteristics were: tooth 51 was most affected; falls, at home, on a ceramic floor, were the main cause; gingival laceration, enamel fracture and intrusive luxation were the most frequent types of trauma; premature tooth loss of primary teeth and enamel discoloration in their successor were the most frequent sequelae; and injuries in the periodontal tissue were demonstrated as the highest risk for sequelae in successors (OR, 3.798; p< 0.001).

CONCLUSIONS

Most traumatic injuries occur in young children, in their home environment. Consequences for the primary teeth were more frequent compared to the permanent successor tooth. Traumatized primary teeth involving periodontal tissue have more chances to result in sequelae to their successor teeth.

Primary tooth pulpectomy overfilling by different placement techniques: A systematic review and meta-analysis

Background. This study was conducted to investigate root canal overfilling with different material placement techniques in primary teeth. Methods. A systematic search was undertaken by searching PubMed/MEDLINE and Scopus for English language peer-reviewed articles published until February 2018 that reported primary tooth pulpectomy overfilling. Two reviewers independently screened and identified studies in terms of the selection criteria and independently collected the data using a specially designed data extraction form. The overfilling rate was the primary summary measure. The weighted pooled overfilling rates were estimated by random-effects meta-analysis. Results. Twenty clinical and four in vitro studies met the eligibility criteria. In the clinical studies, the pooled overfilling rate for zinc oxide-eugenol (ZOE) was 23.3% with a lentulo spiral mounted on a handpiece, 22.7% with a hand-held lentulo spiral, and 17% with a plugger. The pooled overfilling rate for calcium hydroxide-based materials was 16.7% with a lentulo spiral mounted on a handpiece, 14.7% with a hand-held lentulo spiral, 19.6% with a syringe, and 25.7% with a plugger. In the in vitro studies, neither individual overfilling rates nor two-by-two comparisons were subjected to meta-analysis because of an inadequate number of studies. Conclusion. The lowest overfilling rate in the clinical studies was related to plugger and handheld lentulo spiral techniques for ZOE and calcium hydroxide-based materials, respectively.

Pulp repair response after the use of a dentin-pulp biostimulation membrane (BBio) in primary teeth: study protocol for a randomized clinical trial

Background

Vital pulp therapy aims at maintaining the pulp tissue injured but vital. Thus, the use of capping materials that induce tissue regeneration is a great current trend. This study aims to evaluate clinically and radiographically the pulp repair after the use of dentin-pulp biostimulation membrane in primary teeth.

Methods

Four hundred and sixty-eight teeth from children aged between 5 and 9 years old, both genders, with deep caries lesion with pulp involvement, but no furcal impairment and any sign of necrosis will be selected. The vital pulp therapy will be performed with mineral trioxide aggregate (control group) and dentin-pulp biostimulation chitosan membrane (BBio group). The clinical and radiographic outcomes will be assessed at 12 and 24 months after treatment. The thickness of the dentin barrier will be verified through Image J2 software. The Wilcoxon signed rank test and Mann-Whitney test will respectively compare the intra- and intergroup clinical and radiographic outcomes. Paired t test and independent t test will respectively compare the intra- and intergroup radiographic measurements. The logistic regression will be applied, and the degrees of this association will be measured using odds ratio (OR) and 95% confidence interval (95% CI).

Discussion

Therefore, this study protocol aims at new perspectives of vital pulp therapy of primary teeth by employing new easy-handling, low-cost material to keep viable the pulp tissue capable of regenerating and maintain the physiological process of deciduous tooth exfoliation.

Trial registration

Brazilian Registry of Clinical Trials RBR-6vr58b. Registered on 17 February 2019.

Litterfall Hg deposition to an oak forest soil from southwestern Europe

Litterfall constitutes one of the main vectors for mercury (Hg) transfer to forested ecosystems, so we studied the deposition of Hg through senescent vegetation (oak leaves, twigs and miscellaneous) in a deciduous forest plot of Southwest Europe dominated by Quercus robur in 2015 and 2016. Total Hg concentrations increased in the following order: bole wood (1.4 μg kg^-1) < bark (8.3 μg kg^-1) < twigs (12.2 μg kg^-1) < miscellaneous (36.0 μg kg^-1) < oak leaves (39.3 μg kg^-1) < mineral soil (42.4 μg kg^-1) < Oi horizons (48.7 μg kg^-1) < Oe + Oa horizons (71.6 μg kg^-1). Mercury accumulation rates in oak leaves during the growing season were 0.15-0.18 μg kg^-1 day^-1. Mercury deposition fluxes were 26 and 21 μg m^-2 yr^-1 for 2015 and 2016, respectively, with oak leaves being the fraction that contributed the most. Mercury determination in litterfall sorted biomass fractions lead to a more accurate estimation of the total annual Hg deposition fluxes through litterfall. Higher Hg content was obtained for organic horizons (average of 60.2 μg kg^-1) than for mineral soil (mean of 42.4 μg kg^-1), but the soil Hg pool was higher in the latter. The results confirmed the necessity of taking into account the Hg pool in the deeper mineral soil layers as they accumulate substantial quantities of Hg associated to organic C and Al compounds, preventing its mobilization to other compartments of the terrestrial ecosystems.

Cytocompatibility of filling pastes by primary teeth root simulating model

Evaluate the cytocompatibility of Calen^®/ZO, Calcicur^®, Vitapex^®, Endoflas^®, and zinc oxide/eugenol-based (ZOE) root canal pastes (RCP) to human primary osteoblasts (HPO) through a simplified model for primary teeth. The model employed pipette tips filled with 0.037 g of paste, exposed to 185 µL of culture medium for 24 h (n = 6). Release of components was analysed by Proton Nuclear Magnetic Resonance Spectroscopy (¹H-NMR). HPO were exposed to conditioned media for 24 h. Cell viability was assessed by cell density and metabolic activity, and release of interleukin 6 (IL-6), vascular endothelial growth factor (VEGF) and fibroblast growth factor (bFGF) by immunological assay. Physicochemical properties and antimicrobial efficacy were also evaluated. ¹H-NMR spectra analysis showed similarity between ZOE, Endoflas^®, Calcicur^®, and Vitapex^® compared to Calen^®/ZO and positive control, which showed distinct released components. Calen^®/ZO and Calcicur^® exhibited high alkaline pH in all periods and showed similar solubility. Calen^®/ZO, ZOE, and Vitapex^® showed similar flow rate. Calen^®/ZO, Calcicur^®, and Vitapex^® did not exhibit antimicrobial efficacy. Calen^®/ZO presented cytotoxicity (p < 0.05). Pastes did not increase IL-6 release compared to control. Apart from Vitapex^®, all pastes significantly induced VEGF/bFGF release. Interactive effects among released products may affect biological response to filling pastes. Calcicur^®, ZOE, Endoflas^® and Calen^®/ZO presented good to moderate cytocompatibility, with low impact on pro-inflammatory cytokine release and induction of growth factors of interest to tissue repair. This simplified model, specific for the evaluation of the cytocompatibility of RCPs on primary teeth, suggests how these pastes might contribute to bone repair in clinical situations of apical periodontitis in children.

A Biobank of Stem Cells of Human Exfoliated Deciduous Teeth: Overview of Applications and Developments in Brazil

A biobank is an organized collection of biological human material and its associated information stored for research according to regulations under institutional responsibility, without commercial purposes, being a mandatory and strategical activity for research, regenerative medicine, and innovation. Stem cells have largely been employed in research and frequently stored in biobanks, which have been used as an essential source of biological materials. Stem cells of human exfoliated deciduous teeth (SHED) are stem cells which have a high multipotency and can be easily obtained. Besides, this extremely accessible tissue has advantages with respect to storage, as the SHED obtained in childhood can be used in later life, which implies the necessity for the creation and regulation of biobanks. The proper planning for the creation of a biobank includes knowledge of the material types to be stored, requirements regarding handling and storage conditions, storage time, and room for the number of samples. Thus, this study aimed to establish an overview of the development of a SHED biobank. Ethical and legal standardization, current applications, specific orientations, and challenges for the implementation of a SHED biobank were discussed. Through this overview, we hope to encourage further studies to use SHED biobanks.

Coincidence of Fusion and Concrescence in Mandibular Deciduous Incisors: A Case Report

AIM

The aim of this paper is to report a rare case in which two dental anomalies in primary dentition coexisted-fusion and concrescence in a 4-year-old boy. This highlights the significance of the accurate early diagnosis of these dental anomalies.

BACKGROUND

Odontogenic anomalies are frequently encountered in dental practice. These anomalies can occur due to abnormalities during the differentiation stage and lead to abnormalities in the hard tissue formation. Dental anomalies in number and form include fusion, gemination, and concrescence.

CASE DESCRIPTION

Primary dentition with fusion between the right central and lateral primary incisors with increased mesiodistal width. Concrescence between the left central and lateral primary incisors with a groove through the incisal edge. Clinical observation along with radiographic evaluation using intraoral periapical (IOPA) radiographs and orthopantomogram (OPG) were used to arrive at a diagnosis.

CONCLUSION

Early diagnosis of concrescence will reduce the risk of possible complications associated with any need of extraction later on. Monitoring the patient and long-term follow-up is required to manage the case with coexisting anomalies of true fusion and acquired concrescence.

CLINICAL SIGNIFICANCE

A thorough history taking and clinical and radiographic evaluation of fusion and concrescence at an early stage result in an accurate diagnosis. A careful monitoring plan is a key to reduce the risk of possible complications later on.

Are soils beneath coniferous tree stands more acidic than soils beneath deciduous tree stands?

In 2008, the Mulberry River, a National Wild and Scenic River, was listed as impaired due to low pH (below pH 6.0). Over the last 50 years, the volume of conifers in the Ozark region has increased 115% since 1978 which may result in the acidification of nearby aquatic ecosystems. The objective of this study was to determine if differences exist in soil and litter chemical properties between deciduous and coniferous tree stands. Aboveground litter (n = 200) and soil (n = 400) at 0- to 5- and 5- to 15-cm depths were collected at paired deciduous and coniferous stands at 10 locations within the Mulberry River watershed and analyzed for a suite of chemical parameters. There were no differences (P > 0.05) in several measures of soil acidity between deciduous and coniferous stands. Litter collected from the coniferous stands was more acidic than deciduous litter (4.4 vs 4.7; P < 0.05). Cation exchange capacity, exchangeable Ca and Mg, and water-soluble P and Mg contents differed (P < 0.05) by stand and depth. Cation exchange capacity and exchangeable Ca and Mg were greatest in the 0- to 5-cm depth interval of the coniferous stands. Water-soluble P and Mg contents were greatest within the 0- to 5-cm depth interval which did not differ (P > 0.05) between stand but were greater than the 5- to 15-cm depth interval. Although limited to the top 15-cm of soil, the similarity in soil acidity between stands suggests that conifer growth may not be a substantial source of acidity to the Mulberry River.

Deproteinization of primary enamel with sodium hypochlorite before phosphoric acid etching

The aim of this study was to evaluate the deproteinization of primary enamel by analyzing etching pattern types, with and without the application of 5% NaOCl before acid etching with 37% H3PO4. Fifteen extracted human primary molars were randomly selected for the present in vitro study; 1mm x 1mm blocks were prepared and divided into two groups (n = 21). These groups were treated as follows: Group A- Acid Etching with 37% H3PO4 gel for 15 s; Group B- 5% NaOCl for 60 s + Acid Etching with 37% H3POfor 15 s. The specimens were prepared for scanning electron microscopy analysis. The images were evaluated for quality types I and II etching of the enamel surface using ImageJ software. Datasets were checked for normality by Kolgomorv-Smirnov test and the nonparametric unpaired Mann-Whitney test was applied. The mean surface area of type I and II etching pattern values was 1922.314 µm2for Group A and 3840.473 µm2Group B. We conclude that deproteinization with 5% NaOCl prior to acid etching can be used to increase the area of adhesion and the quality of the etching pattern.

Parental Knowledge and Awareness of the First Permanent Molar

Background and Aim

This study aimed to assess the awareness of parents about the presence of first permanent molar and its effect on the health of this tooth.

Materials and methods

This cross-sectional research has been done on 250 elementary school students which were 6 to 8-year-old boys and their parents in Tehran city. Sampling was done randomly. The questionnaires were filled out by the parents, and then tooth condition was registered in a visit formfor each student separately. Next, the related children’s decayed missing filled teeth (DMFT) was determined and recorded. The mean value was calculated. Data were analyzed using the statistical package for the social sciences (SPSS) via a generalized estimating equation.

Results

There was a significant relationship between parental awareness of being permanent of the first permanent molar and DMFT (p < 0.05).

Conclusion

Socio-economical factors like parental education can have an effect on oral health condition.

How to cite this article: Heydari A, Shahrabi M, Shafizadeh M, Anaraki EA, Aref M, Parental Knowledge and Awareness of the First Permanent Molar. Int J Clin Pediatr Dent, 2018;11(5):382-385.

The use of fluoride for the prevention of dental erosion and erosive tooth wear in children and adolescents

BACKGROUND

Erosive tooth wear (ETW) has gained increasing clinical relevance. It is estimated that worldwide 30-50% of deciduous and 20-45% of permanent teeth are affected. One of the most important nutritional factors causing ETW is the overconsumption of soft drinks, but also patient-related factors like reflux or eating disorders can lead to erosive lesions. Whether acids lead to erosive demineralisation depends on their degree of saturation with respect to tooth mineral at their actual pH.

REVIEW

Fluoride compounds like sodium or amine fluoride seem to be of limited efficacy against erosion, the main reason for this is the missing biofilm in the erosive process as well as the lower pH of the acids compared to bacterial acids. This means that to achieve some kind of preventive effect it would be necessary to use products with higher fluoride concentration, which is not an appropriate option for small children, and/or to increase the frequency of application. In addition, the fluoride compound plays a role as promising effects were found when fluoride is combined with titanium or stannous ions. TiF₄ can cause acid-resistant surface coatings and when Sn²⁺/F^- formulations are applied, Sn is not only found on the surface but is also incorporated into enamel and dentine. Both effects make the tooth surface more resistant against acid demineralisation. Different fluoride-containing vehicles have been tested to prevent erosion/ETW, such as toothpastes, rinses, gels and varnishes. Toothpastes offer some degree of protection, especially Sn²⁺-containing formulations, but effects of the active ingredients are sometimes counteracted by the presence of abrasives.

CONCLUSION

Detecting associated factors and influencing them is the main instrument in arresting erosive tooth wear. Additionally, patients at risk for dental erosion should always use an additional fluoride source preferably containing Sn²⁺.

Evaluation of Dentin-Pulp Complex Response after Conservative Clinical Procedures in Primary Teeth

Introduction

Although selective caries tissue removal decreases the number and diversity of bacteria, stops the caries process, and reduces the risk of pulp exposure, the studies on the minimally removal of caries tissue are limited and further clinical research is necessary in this field.

Aim

This study aimed to evaluate through clinical and radiographic assessments the in vivo response of the dentin-pulp complex of human deciduous teeth after either partial or total caries removal (TCR).

Materials and methods

A total of 49 deciduous molars of children aged between 5 and 9 years were carefully selected. The teeth were divided into two groups: Group I: Partial removal of caries; group II: Total removal of caries. Clinical and radiographic evaluations were performed during the period of 4 to 6 months after the procedure. The intraexam-iner reproducibility was determined by Kappa test. Fisher’s exact test was used to determine the statistical difference between groups.

Results

All teeth showed clinical success during the 4- to 6-month evaluation period. The radiographic evaluation showed 94.2 and 89.6% of success rate in groups I and II respectively. Radiographic results did not show statistically significant differences between the studied groups (p > 0.05).

Conclusion

The partial caries removal (PCR) showed satisfactory clinical and radiographic outcomes, suggesting that this minimally invasive approach might replace the TCR when correctly indicated.

How to cite this article: Mello B, Stafuzza TC, Vitor L, Rios D, Silva T, Machado M, Oliveira TM. Evaluation of Dentin-Pulp Complex Response after Conservative Clinical Procedures in Primary Teeth. Int J Clin Pediatr Dent 2018;11(3):188-192.

The Effect of Er:YAG Laser on Entroccocus faecalis Bacterium in the Pulpectomy of Anterior Primary Teeth

Introduction: Successful root canal therapy depends on the complete elimination of microorganisms such as Entroccocus faecalis, which is impossible to achieve with the traditional methods. Lasers are recently introduced as a new method to solve the problem. The present study is planned and performed to examining the antibacterial effect of Er: YAG laser. Methods: Sixty extracted anterior primary teeth were prepared and sterilized. E. faecalis bacterium was cultured in canals. Samples were randomly divided into two groups. The first group was disinfected by NaOCl 5/25% and Er: YAG laser and the second group just by NaOCl 5/25%. Samples of canal contents were cultured and colony counts were calculated. The results were analyzed statistically by SPSS software and Mann Whitney test. Results: There was no significant difference between colony counts in both groups (P=0.142). But the number of colonies in the first group was lower than in the second group. Conclusion: Although, Er: YAG laser cannot completely eliminate E. faecalis bacterium, its simultaneous use with NaOCl decreases E. faecalis.

Comparison of the Level of Substance P and Neurokinin A in Gingival Crevicular Fluid of Sound and Symptomatic Carious Primary Teeth by ELISA

OBJECTIVES

Pulpal inflammation is often associated with odontogenic pain. Dental pulp is abundantly innervated with sensory fibers encompassing neuropeptides. Neurokinin A (NKA) and substance P (SP) are important neuropeptides in the dental pulp that can cause neurogenic inflammation. Since no previous study has assessed dental pulp neuropeptides in children, this study aimed to compare the level of NKA and SP in gingival crevicular fluid (GCF) of sound and symptomatic carious primary teeth.

MATERIALS AND METHODS

Samples of GCF were obtained of 20 sound and 20 painful carious primary teeth. Enzyme-linked immunosorbent assay (ELISA) was used to quantify neuropeptides in GCF. Data were analyzed using paired t-test, ANOVA, Kolmogorov-Smirnov test and correlation coefficient test.

RESULTS

A significant difference was noted in the level of NKA in GCF of painful and sound teeth (2.23 pg/ml in painful, and 1.84 pg/ml in sound teeth, P<0.05). The difference between the two groups regarding SP was not significant (2.23 pg/ml in painful, and 2.02 pg/ml in sound teeth, P>0.05).

CONCLUSIONS

The results showed that the level of NKA and SP was higher in GCF of painful teeth compared to that of sound teeth. This difference was statistically significant with regard to NKA. Thus, these neuropeptides can serve as indicators for pathological activities in teeth with symptomatic irreversible pulpitis.

Leaf habit does not determine the investment in both physical and chemical defences and pair-wise correlations between these defensive traits

Plant life-history strategies associated with resource acquisition and economics (e.g. leaf habit) are thought to be fundamental determinants of the traits and mechanisms that drive herbivore pressure, resource allocation to plant defensive traits, and the simultaneous expression (positive correlations) or trade-offs (negative correlations) between these defensive traits. In particular, it is expected that evergreen species - which usually grow slower and support constant herbivore pressure in comparison with deciduous species - will exhibit higher levels of both physical and chemical defences and a higher predisposition to the simultaneous expression of physical and chemical defensive traits. Here, by using a dataset which included 56 oak species (Quercus genus), we investigated whether leaf habit of plant species governs the investment in both physical and chemical defences and pair-wise correlations between these defensive traits. Our results showed that leaf habit does not determine the production of most leaf physical and chemical defences. Although evergreen oak species had higher levels of leaf toughness and specific leaf mass (physical defences) than deciduous oak species, both traits are essentially prerequisites for evergreenness. Similarly, our results also showed that leaf habit does not determine pair-wise correlations between defensive traits because most physical and chemical defensive traits were simultaneously expressed in both evergreen and deciduous oak species. Our findings indicate that leaf habit does not substantially contribute to oak species differences in plant defence investment.

Effectiveness of Morinda citrifolia juice as an intracanal irrigant in deciduous molars: An in vivo study

Background:

The purpose of this study was to evaluate the microbial reduction in deciduous molars using Morinda citrifolia juice (MCJ) as irrigating solution.

Materials and Methods:

This was a randomized comparative study including 60 deciduous molars chosen among the patients belonging to the age group of 6–9 years based on the inclusion or exclusion criteria. The selected teeth were divided randomly into two groups based on irrigation solution used, that was, Group I (1% NaOCl) and Group II (MCJ). The microbial samples were collected both pre- and post-irrigation and were transferred for microbial assay. Paired t-test was used for intragroup analysis of pre- and post-operative mean reduction of bacterial colony forming unit (CFU)/ml, whereas Independent t-test was used to assess the intergroup, pre- and post-operative mean reduction of bacterial CFU/ml.

Results:

In the intragroup comparison, both of the groups showed statistically significant (P < 0.001) reduction in the mean CFU/ml; however, it did not show statistically significant reduction when intergroup comparison was carried out between the two groups. Both the study materials had clinically revealed decrease in the microbial count postirrigation.

Conclusion:

Both the irrigants, 1% NaOCl and MCJ, were significantly effective in the reduction of mean CFUs/ml postoperatively. The results of this study have confirmed the antibacterial effectiveness of MCJ in the root canals of deciduous teeth. Considering the low toxicity and antibacterial effectiveness of MCJ, it can be advocated as a root canal irrigant in endodontic treatment of primary teeth.

Prenatal vitamin D and enamel hypoplasia in human primary maxillary central incisors: a pilot study

Background

Enamel hypoplasia (EH) increases risk for dental caries and also is associated with vitamin D deficiencies. This pilot study evaluates the feasibility to determine the association of human maternal circulating vitamin D concentrations during pregnancy and EH in infant's teeth that develop in utero.

Methods

A pilot population of 37 children whose mothers participated in a RCT of vitamin D supplementation during pregnancy was evaluated. Major outcome was EH and major exposure was maternal monthly serum circulating 25(OH)D concentrations during pregnancy. EH was assessed using the Enamel Defect Index and digital images made by a ProScope High Resolution™ handheld digital USB microscope at 50x magnification.

Results

During initial 8 weeks of study, 29/37 children had evaluable data with mean age of 3.6 ± 0.9 years; 48% male; and 45% White, 31% Hispanic, and 24% Black. EH was identified in 13 (45%) of the children. Maternal mean 25(OH)D concentrations were generally lower for those children with EH.

Conclusions

Preliminary results suggest follow-up of children of mothers in a vitamin D supplementation RCT during pregnancy provides an important approach to study the etiology of EH in the primary teeth. Further study is needed to discern thresholds and timing of maternal serum 25(OH)D concentrations during pregnancy associated with absence of EH in teeth that develop in utero. Potential dental public health implications for prevention of early childhood caries via sound tooth structure as related to maternal vitamin D sufficiency during pregnancy need to be determined.

Alternative approach for carious tissue removal in primary teeth

BACKGROUND

Minimally-invasive techniques for the management of carious dental tissue has been well documented. This study aimed to report on the clinical and radiographic response after partial caries removal on left mandibular primary second molar.

CASE REPORT

A 6-year-old boy sought treatment because of pain in the left mandibular primary second molar. The tooth had a deep caries lesion on the occlusal surface, with loss of enamel structure and dentine proximity with the pulp confirmed by periapical radiograph. According to the clinical and radiographic diagnosis, partial caries removal was the treatment of choice. Calcium hydroxide cement was used as pulp capping material.

FOLLOW-UP

In this case report, partial caries removal showed satisfactory clinical and radiographic outcomes after 18-month following-up period.

CONCLUSION

Partial caries removal only is applicable when properly indicated. However, further clinical studies with longer following-up periods are necessary.

Phenological variation of leaf functional traits within species

A basic assumption of the trait-based approach in plant ecology is that differences in functional trait values are greater between species than within species. We questioned this assumption by assessing (1) the relative extent of inter- and intraspecific leaf trait variation throughout a complete growing season (phenological variation) in a group of deciduous and evergreen woody species, and (2) whether species rankings based on leaf traits were maintained across the growing season. We analysed leaf mass per area (LMA) and leaf nutrient concentrations (C, N, P), including the C:N and N:P ratios. Intraspecific trait variation (ITV) due to phenology was significantly greater than interspecific variation for leaf N concentration on a mass basis (Nm; 68.90 %) and for the leaf C:N ratio (60.60 %), whereas interspecific variation was significantly higher than ITV for LMA (62.30 %) and for leaf C concentration on a mass (Cm) and area (Ca) basis (Cm 70.40 %; Ca 65.30 %). ITV was particularly low for LMA (<20 %). Species rankings were highly modified by phenology for a number of leaf traits (Pm, N:P ratio) but were relatively well conserved throughout the growing season for others (LMA, Nm). Patterns of ITV across the growing season differed significantly between deciduous and evergreen species for all traits except leaf P but did not vary between native and exotic species. Overall, our results show that intraspecific phenological variation in leaf traits may be similar to or greater than interspecific variation and that temporal patterns of ITV vary considerably among traits and species, especially for leaf nutrient concentrations, factors which can potentially affect quantitative interspecific relationships.

Morphological aspects and physical properties of enamel and dentine of Sus domesticus: A tooth model in laboratory research

This study aims to describe and analyze morphological and physical properties of deciduous teeth of Sus domesticus. Ultrastructural analysis, mineral composition and microhardness of enamel and dentine tissues were performed on 10 skulls of S. domesticus. External anatomic characteristics and the internal anatomy of the teeth were also described. Data regarding microhardness and ultrastructural analysis were subjected to statistical tests. For ultrastructural analysis, we used the analysis of variance (ANOVA) with Tukey's post hoc (p≤0.05) test. In the analysis of microhardness, the difference between the enamel and dentine tissues was analyzed by a Student's t test. Values were expressed as mean with standard error. The results of ultrastructural analysis showed the presence of an enamel prism pattern. A dentinal tubule pattern was also observed, with a larger diameter in the pulp chamber and the cervical third, in comparison to middle and apical thirds. We observed an average microhardness of 259.2kgf/mm(2) for enamel and 55.17kgf/mm(2) for dentine. In porcine enamel and dentine, the chemical elements Ca and P showed the highest concentration. The analysis of internal anatomy revealed the presence of a simple root canal system and the occurrence of main canals in the roots. The observed features are compatible with the functional demand of these animals, following a pattern very similar to that seen in other groups of mammals, which can encourage the development of research using dental elements from the pig as a substitute for human teeth in laboratory research.

In Vitro Comparison of the Effects of Diode Laser and CO2 Laser on Topical Fluoride Uptake in Primary Teeth

OBJECTIVES

Fluoride therapy is important for control and prevention of dental caries. Laser irradiation can increase fluoride uptake especially when combined with topical fluoride application. The objective of this study was to compare the effects of CO2 and diode lasers on enamel fluoride uptake in primary teeth.

MATERIALS AND METHODS

Forty human primary molars were randomly assigned to four groups (n=10). The roots were removed and the crowns were sectioned mesiodistally into buccal and lingual halves as the experimental and control groups. All samples were treated with 5% sodium fluoride (NaF) varnish. The experimental samples in the four groups were irradiated with 5 or 7W diode or 1 or 2W CO2 laser for 15 seconds and were compared with the controls in terms of fluoride uptake, which was determined using an ion selective electrode after acid dissolution of the specimens. Data were analyzed by SPSS version 16 using ANOVA treating the control measurements as covariates.

RESULTS

The estimated amount of fluoride uptake was 59.5± 16.31 ppm, 66.5± 14.9 ppm, 78.6± 12.43 ppm and 90.4± 11.51 ppm for 5W and 7 W diode and 1W and 2 W CO2 lasers, respectively, which were significantly greater than the values in the conventional topical fluoridation group (P<0.005). There were no significant differences between 7W diode laser and 1W CO2 laser, 5W and 7W diode laser, or 1W and 2W CO2 laser in this regard.

CONCLUSION

The results showed that enamel surface irradiation by CO2 and diode lasers increases the fluoride uptake.

Does Timing of Eruption in First Primary Tooth Correlate with that of First Permanent Tooth? A 9-years Cohort Study

Background and aims. Predicting the teeth eruption time is a valuable tool in pediatric dentistry since it can affects scheduling dental and orthodontic treatments. This study investigated the relationship between the eruption time of first primary and permanent teeth and the variation in the eruption time considering socioeconomic status (SES) in a 9-year population- based cohort study.

Materials and methods. 307 subjects were examined at bimonthly intervals during the first and second years of life and then at six-month intervals until the eruption of first permanent tooth. Eruption times of primary and permanent tooth were recorded for each child. A modified form of Kuppuswamy’s scale was used to assess the SES.

Results. Among 267 subjects completed all follow-ups, the eruption time for first primary and permanent teeth indicated a direct strong correlation; in that one month delayed or early eruption of firstprimary tooth resulted in 4.21 months delayed or early eruption of first appearing permanent tooth (r = 0.91, n = 267, P <0.001). No significant correlation was observed between the eruption time of first primary and first permanent teeth and SES (P = 0.67, P = 0.75, respectively).

Conclusion. The eruption timing for the first primary tooth had a correlation with the first permanent tooth eruption tim-ing, while SES did not have any influence on eruption times.

Clinical Course and Treatment of a Triplication Defect: A Case Report

Fusion is an anomaly manifested in both deciduous and permanent dentitions. Fusion of dental tissues in the primary dentition is of clinical significance owing to the challenges in treatment of the affected teeth and aberrations encountered in development and eruption of their successors. Triple tooth refers to the union of three separate tooth entities. It can occur by fusion, germination, concrescence or a combination of both fusion and germination. Triplication is rarely encountered in the deciduous dentition. The case presented herein describes triplication of deciduous incisors and a supernumerary tooth. The diagnosis was confirmed with the help of radiographs, computed tomography (CT) imaging and histological examination. Retention of the triple tooth had led to crossbite. Extraction was performed for the triple tooth and crossbite was corrected using a composite inclined plane.

Radicular Cyst associated with Deciduous Incisor: A Rare Case Report

Radicular cysts are considered rare in the primary dentition, comprising only 0.5 to 3.3% of the total number of radicular cysts in both primary and permanent dentitions. The aim of this case report is to present the clinical, radiographic and histological characteristics of radicular cyst associated with primary central incisor. Extraction and enucleation of the cyst was carried out under local anesthesia after elevation of the mucoperiosteal flap, which led to uneventful healing.

How to cite this article: Subramanya PL. Radicular Cyst associated with Deciduous Incisor: A Rare Case Report. Int J Clin Pediatr Dent 2012;5(3):217-219.

Submerged and Impacted Primary Molars

Submerged tooth is the one that is depressed below the occlusal plane. Dental ankylosis is thought to be a major cause of submergence. Submerged deciduous teeth have the potential to cause malocclusion not only by prevention of their exfoliation and subsequent replacement by permanent teeth but also by causing tilting of proximal teeth and extrusion of opposing tooth. The purpose of this report is to present three different cases of submerged deciduous teeth and their clinical effects.

Root canal cleaning efficacy of rotary and hand files instrumentation in primary molars

INTRODUCTION

Pulpectomy of primary teeth is commonly carried out with hand files and broaches; a tricky and time consuming procedure. The purpose of this in vitro study was to compare the cleaning efficacy and time taken for instrumentation of deciduous molars using hand K-files and Flex Master rotary system.

MATERIALS AND METHODS

In this study, 68 canals of 23 extracted primary molars with at least two third intact roots and 7-12 mm length were selected. After preparing an access cavity, K-file size #15 was introduced into the root canal and India ink was injected with an insulin syringe. Sixty samples were randomly divided in to experimental groups in group I (n=30), root canals were prepared with hand K-files; in group II (n=30), rotary Flex Master files were used for instrumentation, and in group III 8 remained samples were considered as negative controls. After clearing and root sectioning, the removal of India ink from cervical, middle, and apical thirds was scored. Data was analyzed using student's T-test and Mann-Whitney U test.

RESULTS

There was no significant difference between experimental groups cleaning efficacy at the cervical, middle and apical root canal thirds. Only the coronal third scored higher in the hand instrumented group (P<0.001). Instrumentation with Flex Master rotary files was significantly less time consuming (P<0.001).

CONCLUSION

Although there was no difference in cleanliness efficacy at the apical and middle thirds, the coronal third was more effectively cleaned with hand files. Predictably, time efficiency was a significant advantage with rotary technique.

Investigating leaf lifespans with interval-censored failure time analysis

•  Here leaf lifespans were investigated using interval-censored failure time analysis. The utility of this relatively novel approach is illustrated by comparing the leaf lifespan of winter-deciduous fuchsia (Fuchsia excorticata) and annual-evergreen wineberry (Aristotelia serrata). •  Leaf emergence and mortality were first described using growth equations. Individual leaf lifespans were investigated using a parametric failure-time regression model that accounted for the interval-censored nature of leaf lifespan data. •  Bud burst began 7 d earlier, the rate of leaf emergence was 0.06 leaves per shoot d^-1 faster, and emergence ended 44 d earlier in fuchsia than in wineberry. The rate of leaf mortality was greatest in mid-summer in fuchsia, but nearly constant over the year for wineberry. There was a highly significant effect of the date of leaf emergence on leaf lifespan. Leaves emerging earlier in the growing season had shorter lifespans relative to later emerged leaves in fuchsia, whereas the reverse was true for wineberry. There was no significant effect of shoot height, branch order, or the number leaves of per shoot length on leaf lifespan. •  These results highlight the utility of studying phenology at the individual leaf level using failure time analysis. Although growth equations precisely describe leaf emergence and mortality in wineberry and fuchsia, they obscured key differences between the species that were identified using failure time analysis.

Different photosynthesis-nitrogen relations in deciduous hardwood and evergreen coniferous tree species

The relationship between photosynthetic capacity (A _max) and leaf nitrogen concentration (N) among all C₃ species can be described roughly with one general equation, yet within that overall pattern species groups or individual species may have markedly different A _max-N relationships. To determine whether one or several predictive, fundamental A _max-N relationships exist for temperate trees we measured A _max, specific leaf area (SLA) and N in 22 broad-leaved deciduous and 9 needle-leaved evergreen tree species in Wisconsin, United States. For broad-leaved deciduous trees, mass-based A _max was highly correlated with leaf N (r ²=0.75, P<0.001). For evergreen conifers, mass-based A _max was also correlated with leaf N (r ²=0.59, P<0.001) and the slope of the regression (rate of increase of A _max per unit increase in N) was lower (P<0.001) by two-thirds than in the broad-leaved species (1.9 vs. 6.4 μmol CO₂ g^-1 N s^-1), consistent with predictions based on tropical rain forest trees of short vs. long leaf life-span. On an area basis, there was a strong A _max-N correlation among deciduous species (r ²=0.78, P<0.001) and no correlation (r ²=0.03, P>0.25) in the evergreen conifers. Compared to deciduous trees at a common leaf N (mass or area basis), evergreen trees had lower A _max and SLA. For all data pooled, both leaf N and A _max on a mass basis were correlated (r ²=0.6) with SLA; in contrast, area-based leaf N scaled tightly with SLA (r ²=0.81), but area-based A _max did not (r ²=0.06) because of low A _max per unit N in the evergreen conifers. Multiple regression analysis of all data pooled showed that both N (mass or area basis) and SLA were significantly (P<0.001) related to A _max on mass (r ²=0.80) and area (r ²=0.55) bases, respectively. These results provide further evidence that A _max-N relationships are fundamentally different for ecologically distinct species groups with differing suites of foliage characteristics: species with long leaf life-spans and low SLA, whether broad-leaved or needle-leaved, tend to have lower A _max per unit leaf N and a lower slope and higher intercept of the A _max-N relation than do species with shorter leaf life-span and higher SLA. A single global A _max-N equation overestimates and underestimates A _max for temperate trees at the upper and lower end of their leaf N range, respectively. Users of A _max-N relationships in modeling photosynthesis in different ecosystems should appreciate the strengths and limitations of regression equations based on different species groupings.

Relating UV-B radiation screening effectiveness of foliage to absorbing-compound concentration and anatomical characteristics in a diverse group of plants

The ultraviolet-B radiation (UV-B, 300 nm) screening effectiveness of foliage of a diverse group of plants was examined by measuring epidermal transmittance and depth of penetration of UV-B with a fiberoptic microprobe. In addition, the concentration of UV-B-absorbing compounds and various anatomical characteristics were measured to assess whether they were useful predictors of UV-B screening. Sun foliage of naturally growing individuals of seven species were sampled in each of six life forms comprising two evergreen groups (gymnosperms and angiosperms) and four deciduous angiosperm groups (trees, shrubs and vines, herbaceous dicotyledons, and grasses). There was significant life-form variation in epidermal transmittance and depth of penetration of UV-B, concentration of UV-B-absorbing compounds (leaf-area basis), epidermal (including cuticle and hypodermis) thickness, and specific leaf area. Values of these parameters tended to be related to leaf longevity, with the most notable differences apparent between evergreen and deciduous species. The mean epidermal transmittance and depth of penetration of UV-B in foliage averaged 4% and 32 μm in evergreens, compared to 28% and 75 μm in deciduous species. These values are conservative estimates since the microprobe was oriented in foliage such that much of the side- and backscattered UV-B was ignored. The strongest predictors of epidermal transmittance and depth of penetration were epidermal thickness and the concentration of absorbing compounds, which averaged 32 μm and 1.50 A cm^-2 in evergreens, but only 19 μm and 0.99 A cm^-2 in deciduous foliage. However, the variation found in these relationships implies that additional factors warrant consideration in assessing UV-B-screening effectiveness. The relatively ineffective screening of UV-B by foliage of many deciduous plants suggests they may be more responsive to enhanced UV-B than evergreen species.

The effect of nitrogen and phosphorus addition on the growth, reproduction, and nutrient dynamics of two ericaceous shrubs

Aboveground growth, reproduction, and foliar nitrogen and phosphorus contents of two ericaceous shrub species were compared over two seasons in (a) an undisturbed shrub bog (pocosin), and (b) a factorial fertilization design in which three levels each of nitrogen and phosphorus were added in all possible combinations. One species, Zenobia pulverulenta, is deciduous whereas the other species, Lyonia lucida, is evergreen. In the nutrient-poor undisturbed pocosin the two species exhibited similar foliar nitrogen and phosphorus concentrations and aboveground growth rates. Neither species flowered. In response to nutrient-addition Zenobia increased growth rates more than Lyonia. Foliar phosphorus concentrations of both species increased in response to enhanced phosphorus availability. in the first season neither species flowered in any treatment. In the second season Zenobia flowered only in the fertilized plots, with the most flowering in the high phosphorus treatments. I conclude that, by virtue of high growth rates and efficient use of nutrients and despite differences in leaf phenology and morphology, both Lyonia and Zenobia are successful in a competitive community under conditions of extremely low phosphorus availability. However, unlike Lyonia, Zenobia can take advantage of temporarily increased nutrient availability, which occurs following fire in the pocosin, to increase growth and reproduction.