Dental Material Choices for Pulp Therapy in Paediatric Dentistry

Objective:

The purpose of this study was to assess the restorative choices for pulpal therapy by members of the Australian and New Zealand Society of Paediatric Dentistry (ANZSPD).

Methods:

Members of the ANZSPD were sent an online survey asking about the procedures that they performed and their choice of dental materials.

Results:

The respondents were 31 general dentists (GD) and 55 specialist paediatric dentists (PD). Materials used for indirect pulp capping included calcium hydroxide [Ca(OH)₂] cement (CHC), glass ionomer cement or resin-modified glass ionomer cement (GIC/RMGIC), Ca(OH)₂ paste (CHP) and mineral trioxide aggregate (MTA). Materials for direct pulp capping included MTA, CHP and CHC. Materials and techniques used for pulpotomy included MTA, ferric sulphate, formocresol and diathermy, CHP and CHC. GD and PD were similar in their choice of materials. However, there was no preferred product for pulp therapy. Most GD learnt how to use MTA from CPD lectures, while some PD learnt how to use MTA from their postgraduate training as well as CPD lectures. Many GD and PD did not have hands-on training from their education on how to use MTA (GD: 80%, PD: 43%). Most would like to attend hands-on MTA courses (GD: 86%, PD: 65%).

Conclusion:

There was no clear preferred product for the various types of pulp therapy in paediatric dentistry. Education appears to be the major barrier to the use of MTA rather than the cost of MTA.

Endodontic Treatment of Primary Molars with Antibiotic Paste: A Report of 38 Cases

OBJECTIVE

This study presents 38 cases of primary molars with necrotic pulps treated with antibiotics-based paste.

CASE REPORT

The technique consisted of necrotic tissue removal of the pulp chamber, using spoons excavators and low speed drills. Pulp cavity was washed with saline solution and dried with sterile cotton balls. Then an antibiotic paste composed of chloramphenicol, tetracycline, zinc oxide and eugenol - CTZ paste - was inserted at the entrance of root canals. Patients were evaluated clinically and radiographically at different times. The criteria that defined clinical success were the lack of periapical abscess and mobility compatible with chronological age. Radiographic assessments consisted in absence of radiolucency in the region of root bifurcation and pathological bone resorption.

CONCLUSION

There were 100% and 93% of clinical and radiographic success, respectively. The results suggest that the CTZ paste is an optional therapy for pulp of primary molars.

Comparison of compressive strength among three different intracanal post materials in primary anterior teeth: An in vitro study

Objective:

The objective of our study was to compare the fracture resistance and the mode of failure among three different post materials in primary anterior teeth.

Materials and Methods:

A total of sixty extracted primary anterior teeth were selected for the study. The samples were divided into three groups of twenty teeth each: Group I (Ribbond), Group II (Omega loop), and Group III (Glass fiber post). Pulp therapy was followed by intracanal post and crown buildup. The samples were mounted in self-cure acrylic and subjected to compressive strength test using universal testing machine (Instron). The maximum force at which the tooth fractured was recorded.

Results:

The values were subjected to one-way analysis of variance. The mean compressive strength values of Ribbond, omega loop, and glass fiber post were found to be 83.25 N, 61.60 N, and 75.55 N, respectively. The P value was found to be 0.220.

Conclusion:

Group I (Ribbond) showed the highest fracture resistance values followed by Group III (Glass fiber post) and Group II (Omega loop). Although there is difference in mean values, they were nonsignificant.

Surgical Management of Large Radicular Cyst Associated with Mandibular Deciduous Molar Using Platelet-rich Fibrin Augmentation: A Rare Case Report

Radicular cysts arising from deciduous teeth are rare and usually cause a large bony defect. Autologous platelet-rich fibrin (PRF) is an easily available healing biomaterial in oral surgical defect with the new perspective of accelerated healing of a large bony defect. The present case is of unusually large radicular associated with neglected carious mandibular deciduous second molar in 10-year-old girl and its surgical management with PRF augmentation as a healing biomaterial in the bony defect. One-year follow-up showed uneventful healing and eruption of succedaneous tooth. Healing was relatively faster and facilitated by PRF placement. Furthermore, the importance of anticipatory guidance about the treatment of diseased primary teeth and their preservation gets highlighted.

The efficiency of child formula dentifrices containing different calcium and phosphate compounds on artificial enamel caries

OBJECTIVES

Fluoride toothpaste has been extensively used to prevent dental caries. However, the risk of fluorosis is concerning, especially in young children. Calcium phosphate has been an effective remineralizing agent and is present in commercial dental products, with no risk of fluorosis to users. This in vitro study aimed to compare the effects of different calcium phosphate compounds and fluoride-containing dentifrices on artificial caries in primary teeth.

MATERIALS AND METHODS

Fifty sound primary incisors were coated with nail varnish, leaving two 1 mm² windows on the labial surface before immersion in demineralizing solution for 96 hours to produce artificial enamel lesions. Subsequently, one window from each tooth was coated with nail varnish, and all 50 teeth were divided into five groups (n = 10); group A - deionized water; group B - casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (Tooth Mousse); group C - 500 ppm F (Colgate Spiderman^®); group D - nonfluoridated toothpaste with triple calcium phosphate (Pureen^®); and group E - tricalcium phosphate (TCP). Polarized light microscopy and Image-Pro^® Plus software were used to evaluate lesions.

RESULTS

After a 7-day pH-cycle, mean lesion depths in groups A, B, C, D, and E had increased by 57.52 ± 10.66%, 33.28 ± 10.16%, 17.04 ± 4.76%, 32.51 ± 8.99%, and 21.76 ± 8.15%, respectively. All data were processed by the Statistical Package for the Social Sciences (version 16.0) software package. Comparison of percentage changes using one-way analysis of variance and Fisher's least squares difference tests at a 95% level of confidence demonstrated that group A was significantly different from the other groups (P < 0.001). Lesions in groups B and D had a significant lesion progression when compared with groups C and E.

CONCLUSIONS

All toothpastes in this study had the potential to delay the demineralization progression of artificial enamel caries in primary teeth. The fluoride 500 ppm and TCP toothpastes were equal in the deceleration of enamel caries progression and better than CPP-ACP paste and TCP toothpaste.

Prevalence of prematurely lost primary teeth in 5-10-year-old children in Thamar city, Yemen: A cross-sectional study

Objectives:

The premature loss of primary teeth is a potential risk factor for poor arch length development. Adequate arch length is important to the progression of the permanent teeth. Poor arch length can lead to crowding, ectopic eruption, or impaction of these teeth. This study is designed to assess the prevalence of premature loss of primary teeth in the 5-10-year-old age group.

Materials and Methods:

The study group included 185 children, that is, 91 boys and 94 girls. The dental examination was conducted by an experienced examiner under sufficient artificial light. Data including patient age and missing teeth were collected. Descriptive statistics were applied for data analysis, and from the results, Chi-square tests were used at a level of significance of 5% (P < 0.05).

Results:

We observed a 40.54% prevalence of premature loss of primary teeth with no statistically significant difference between genders. The lower left primary second molar was the most commonly absent tooth in the dental arch (13.5%).

Conclusion:

The status of premature loss of primary teeth was high in the study group. Implementation of efficient educational and preventive programs to promote oral health would help children maintain a healthy primary dentition and eventually prevent the disturbances in the future development of normal occlusion. Early detection and management of the space problems associated with the early loss of primary teeth would help in reducing malocclusion problems.

Permanent caries experience is associated with primary caries experience: a 7-year longitudinal study in China

OBJECTIVES

The aim of this study was to evaluate the association between caries experience in primary teeth and caries experience in permanent teeth in a longitudinal study.

METHODS

Teeth were examined at 5 years of age and a follow-up examination was conducted 7 years later at 12 years of age in all children from Jiading District, Shanghai, China. A total of 1885 participants were recruited in the study; 1683 students were followed up and 202 students (10.7%) were lost to follow up. Data were analyzed using the chi-square test, t-test and risk ratio.

RESULTS

The followed-up samples comprised 883 boys (52.5%) and 800 girls (47.5%). At initial examination, the prevalence of dental caries was 67.4% in boys and 66.5% in girls (χ² = 0.2, P = 0.70), with mean decayed, missing and filled teeth (dmft) scores of 3.5 ± 0.1 and 3.4 ± 0.1, respectively (t = 0.1, P = 0.90). At follow-up, the prevalence of dental caries was 33.9% in boys and 37.9% in girls (χ² = 2.9, P = 0.11), with mean DMFT scores in permanent teeth of 0.7 ± 0.0 and 0.8 ± 0.1, respectively (t = 1.2, P = 0.24). The group of 5-year-olds with caries had a significantly higher prevalence of caries in permanent teeth (45.5%) at 12 years of age than the group of 5-year-olds without caries (16.0%) (χ² = 141.1, P < 0.001, risk ratio = 1.5). Caries risk in permanent teeth was significantly higher with greater dmft scores (χ² for trend = 31.1, P < 0.001).

CONCLUSIONS

Caries in primary teeth is a major risk factor for caries in permanent teeth. The likelihood of caries in permanent teeth is higher with greater dmft scores in primary teeth.

Gene therapy improves dental manifestations in hypophosphatasia model mice

BACKGROUND AND OBJECTIVE

Hypophosphatasia is a rare inherited skeletal disorder characterized by defective bone mineralization and deficiency of tissue non-specific alkaline phosphatase (TNSALP) activity. The disease is caused by mutations in the liver/bone/kidney alkaline phosphatase gene (ALPL) encoding TNSALP. Early exfoliation of primary teeth owing to disturbed cementum formation, periodontal ligament weakness and alveolar bone resorption are major complications encountered in oral findings, and discovery of early loss of primary teeth in a dental examination often leads to early diagnosis of hypophosphatasia. Although there are no known fundamental treatments or effective dental approaches to prevent early exfoliation of primary teeth in affected patients, several possible treatments have recently been described, including gene therapy. Gene therapy has also been applied to TNSALP knockout mice (Alpl^-/- ), which phenocopy the infantile form of hypophosphatasia, and improved their systemic condition. In the present study, we investigated whether gene therapy improved the dental condition of Alpl^-/- mice.

MATERIAL AND METHODS

Following sublethal irradiation (4 Gy) at the age of 2 d, Alpl^-/- mice underwent gene therapy using bone marrow cells transduced with a lentiviral vector expressing a bone-targeted form of TNSALP injected into the jugular vein (n = 3). Wild-type (Alpl^+/+ ), heterozygous mice (Alpl^+/- ) and Alpl^-/- mice were analyzed at 9 d of age (n = 3 of each), while Alpl^+/+ mice and treated or untreated Alpl^-/- mice were analyzed at 1 mo of age (n = 3 of each), and Alpl^+/- mice and Alpl^-/- mice with gene therapy were analyzed at 3 mo of age (n = 3 of each). A single mandibular hemi-section obtained at 1 mo of age was analyzed using a small animal computed tomography machine to assess alveolar bone formation. Other mandibular hemi-sections obtained at 9 d, 1 mo and 3 mo of age were subjected to hematoxylin and eosin staining and immunohistochemical analysis of osteopontin, a marker of cementum.

RESULTS

Immunohistochemical analysis of osteopontin, a marker of acellular cementum, revealed that Alpl^-/- mice displayed impaired formation of cementum and alveolar bone, similar to the human dental phenotype. Cementum formation was clearly present in Alpl^-/- mice that underwent gene therapy, but did not recover to the same level as that in wild-type (Alpl^+/+ ) mice. Micro-computed tomography examination showed that gene therapy improved alveolar bone mineral density in Alpl^-/- mice to a similar level to that in Alpl^+/+ mice.

CONCLUSIONS

Our results suggest that gene therapy can improve the general condition of Alpl^-/- mice, and induce significant alveolar bone formation and moderate improvement of cementum formation, which may contribute to inhibition of early spontaneous tooth exfoliation.

Effect of endodontic sealers on bond strength of restorative systems to primary tooth pulp chamber

Background/purpose

Although current literature suggests that root canal sealers affect the bonding ability of restorative systems to pulp chamber dentin of permanent teeth, primary teeth have not been investigated. This study intended to evaluate the microtensile bond strength (μTBS) of three restorative systems to pulp chamber dentin in primary teeth and to determine the effect of two different root canal sealers on the μTBS.

Materials and methods

Ninety primary molars were used in this study. The teeth were randomly divided into three main groups according to canal sealers: (1) control (without sealer); (2) Metapex; and (3) zinc-oxide eugenol. The main groups were further divided into three subgroups depending on the coronal restorative system: (1) compomer (Prime Bond NT + Dyract EXTRA); (2) composite (Clearfil Tri-S Bond + Clearfil Photo Posterior); and (3) resin-modified glass ionomer (Fuji II LC). After restoration, the buccal wall of the pulp chamber was sectioned to obtain sticks (1 mm × 1 mm). The μTBS was then measured. Data were analyzed with two-way analysis of variance, followed by a posthoc test. The interfacial morphology of the bonded space was evaluated using scanning electron microscopy.

Results

In the control group, a significant difference was observed only for the μTBS of the composite (P < 0.05). Compared with the control groups, Metapex and zinc-oxide eugenol significantly reduced the μTBS of restorative systems (P < 0.05).

Conclusion

Composite materials seemed to bond to pulp chamber dentin in primary teeth with a higher strength than compomer and resin-modified glass ionomer. Metapex and zinc-oxide eugenol canal filling materials reduced the bond strength of all three restorative systems.

Assessment of Microleakage of a Composite Resin Restoration in Primary Teeth Following Class III Cavity Preparation Using Er, Cr: YSGG laser: An In Vitro Study

Introduction: Marginal seal integrity is important for a successful adhesive dental restoration. Alterations caused by laser irradiation in the enamel and dentin surface can affect the marginal integrity of adhesive restorations. The aim of this study was to evaluate the microleakage of a composite resin restoration in primary teeth following laser irradiation of enamel and dentin. Methods: Forty freshly extracted sound human primary maxillary and mandibular anterior teeth were used in this study. The teeth were randomly divided into two groups (I and II), with 20 teeth in each. In group I, proximal cavities (Class III) were prepared using an airotor hand -piece and diamond bur. The cavities were etched for 15 seconds with 35% phosphoric acid gel, rinsed with water for 15 seconds, air dried and a bonding agent was applied onto the cavity surfaces and light cured for 20 seconds. The cavities were restored with composite resin and light cured for 40 seconds. In group II, proximal (Class III) cavities were prepared using Erbium, Chromium: Yttrium Scandium Gallium Garnet (Er,Cr:YSGG) (Er,Cr:YSGG) (Biolaseiplus, wave length 2.78 μm). The cavity was then rinsed, air dried and without etching, a bonding agent was applied and light cured for 20 seconds. The cavities were restored in the same manner as that of group I. The treated teeth were mounted on acrylic resin blocks and were subjected to a thermocycling regimen. Following, the teeth were immersed in 2% methylene blue for 24 hours. The teeth were sectioned longitudinally in a bucco-lingual direction using a diamond disc at slow speed. The sections of all the groups were examined under a stereomicroscope for micro-leakage. Results: The mean scores for microleakage in group I was 1.95 ± 1.31 and in group II it was 1.4 ± 1.27. There was no significant difference between the two groups (P = 0.882). Conclusion: No significant difference in microleakage was noticed between the composite resin bonded to lased enamel and dentin and the teeth preparedwith conventional method.

Comparison of removal of endodontic smear layer using ethylene glycol bis (beta-amino ethyl ether)-N, N, N', N'-tetraacetic acid and citric acid in primary teeth: A scanning electron microscopic study

Background:

Root canal irrigants are considered momentous in their tissue dissolving property, eliminating microorganisms, and removing smear layer. The present study was aimed to compare the removal of endodontic smear layer using ethylene glycol bis (beta-amino ethyl ether)-N, N, N', N'-tetraacetic acid (EGTA) and citric acid solutions with saline as a control in primary anterior teeth.

Materials and Methods:

Thirty primary anterior teeth were chosen for the study. The teeth were distributed into three groups having ten teeth each. Following instrumentation, root canals of the first group were treated with 17% EGTA and the second group with 6% citric acid. Only saline was used as an irrigant for the control group. Then, the teeth were subjected to scanning electron microscopy (SEM) study. The scale given by Rome et al. for the smear layer removal was used in the present study.

Results:

The pictures from the SEM showed that among the tested irrigants, 17% EGTA + 5% sodium hypochlorite (NaOCl) group showed the best results when compared to other groups.

Conclusion:

The results advocate that the sequential irrigation of the pulp canal walls with 17% EGTA followed by 5% NaOCl produced efficacious and smear-free root canal walls.

Arresting Dentine Caries with Different Concentration and Periodicity of Silver Diamine Fluoride

Different regimens of silver diamine fluoride (SDF) have been used to manage early childhood caries. So far, there is limited information regarding the concentrations and frequency of applications for effective caries control in primary teeth. This study aimed to compare the efficacy of 2 commercially available SDF solutions at preprepared concentrations of 38% and 12% when applied annually or biannually over 18 mo in arresting dentine caries in primary teeth. This randomized double-blinded clinical trial recruited kindergarten children aged 3 to 4 y who had at least 1 tooth with dentine caries. The children were randomly allocated to receive 4 treatment protocols: group 1, annual application of 12% SDF; group 2, biannual application of 12% SDF; group 3, annual application of 38% SDF; and group 4, biannual application of 38% SDF. Clinical examinations at 6-mo intervals were conducted to assess whether active carious lesions became arrested. Information on the children's background and oral hygiene habits was collected through a parental questionnaire at baseline and follow-up examinations. A total of 888 children with 4,220 dentine carious tooth surfaces received treatment at baseline. After 18 mo, 831 children (94%) were examined. The caries arrest rates were 50%, 55%, 64%, and 74% for groups 1, 2, 3, and 4, respectively (P < 0.001). Lesions treated with SDF biannual application had a higher chance of becoming arrested compared with those receiving SDF annual application (odds ratio, 1.33; 95% confidence interval, 1.04-1.71; P = 0.025). The interaction between concentration and lesion site was statistically significant (P < 0.001). Compared with 12% SDF, the use of 38% SDF increased a chance of becoming arrested (P < 0.05), except lesions on occlusal surfaces. Based on the 18-mo results, SDF is more effective in arresting dentin caries in the primary teeth of preschool children at 38% concentration than 12% concentration and when applied biannually rather than annually. Knowledge Transfer Statement: The results of this study can be used by clinicians and dental public health professionals when deciding which concentrations and frequency of application of silver diamine fluoride solution should be adopted for arresting dentine caries. With consideration of caries arrest treatment with silver diamine fluoride, which is painless, simple, and low cost, this information could lead to more appropriate therapeutic decisions for caries control in young children or those who lack access to affordable conventional dental care.

Risk factors for traumatic dental injuries in the primary dentition: concepts, interpretation, and evidence

The purpose of this comprehensive review is to explore the main concepts related to quantification and interpretation of risk factors and investigate characteristics associated with traumatic dental injuries (TDI) in the primary dentition. Initially, the main concepts related to causality and risk factors were summarized, including how to measure, express, and compare risk as well as interpret statistical significance. Based on a structured search through PubMed, original research articles regarding TDI and associated factors in the primary dentition were then reviewed by two examiners. Studies with a sample size of at least 300 children aged between 0 and 6 years were summarized according to journal, country, study design, and type of statistical analysis. Variables associated with TDI in primary teeth were identified from studies with multivariable analysis. Measures of effect size and P values were presented. Thirty-two studies were retrieved: most were cross-sectional in design and only 17 (53.1%) performed multivariable analysis. Most investigations did not find an association between gender and socioeconomic variables with TDI. Increased overjet was the only factor consistently identified as an associated factor. Behavioral characteristics have been recently investigated and suggested as potential risk factors for TDI in the primary dentition. In conclusion, increased overjet is undoubtedly associated with TDI in the primary dentition. As behavioral factors may be targeted by preventive strategies, their role on TDI occurrence should be clarified in future cohort studies. Clinicians should understand the terms and measures described in studies on risk factors to properly apply knowledge and benefit patients.

Comparison of microleakage from stainless steel crowns margins used with different restorative materials: An in vitro study

Background:

Obtaining optimal marginal adaption with prefabricated stainless steel crowns (SSCs) is difficult, especially after removing dental caries or defects in cervical areas. This situation requires the use of an SSC after tooth reconstruction. This study evaluated microleakage and material loss with five restorative materials at SSC margins.

Materials and Methods:

One hundred and twenty primary molar teeth were randomly divided into six groups (n = 20). Class V cavities were prepared on the buccal surfaces of the teeth in groups 1-5. Cavities were restored with amalgam, resin-based composite, glass ionomer (GI), zinc phosphate, or reinforced zinc oxide eugenol (Zonalin). Group 6 without cavity preparation was used as a control. Restorations with SSCs were prepared according to standard methods. Then, SSCs were fitted so that the crown margins overlaid the restorative materials and cemented with GI. After thermocycling, the specimens were placed in 0.5% fuchsin and sectioned. The proportions of mircoleakage and material loss were evaluated with a digital microscope. Statistical analysis was performed with Kruskal–Wallis and Mann–Whitney tests.

Results:

The groups differed significantly (P < 0.001). Amalgam and GI showed the least microleakage. Amalgam restorations had significantly less microleakage than the other materials (P < 0.05). Microleakage was greatest with resin-based composite, followed by Zonalin. Material loss was greater in samples restored with Zonalin and zinc phosphate.

Conclusion:

When SSC margins overlaid the restoration materials, cavity restoration with amalgam or GI before SSC placement led to less microleakage and material loss. Regarding microleakage and material loss, resin-based composite, zinc phosphate, and Zonalin were not suitable options.

Calcium-Enriched Mixture Pulpotomy of Primary Molar Teeth with Irreversible Pulpitis. A Clinical Study

Objectives:

To evaluate the outcome of vital pulp therapy in primary teeth with irreversible pulpitis by using calcium-enriched mixture (CEM) cement according to clinical and radiographic assessment.

Participants and Methods:

Fifty primary molar teeth with irreversible pulpitis in 50 children aged 6-8 years underwent pulpotomy using CEM cement as the dressing material. Following pulpotomy, pain intensity was evaluated by use of a visual analog scale at 1 and 7 days from the treatment and in clinical appointments at 3, 6 and 12 months after baseline. Radiographic evaluation was performed at 6 and 12 months. Data were analyzed using the McNemar test.

Results:

A total of 42 children (mean age 7.26 ± 0.82 year) completed the study. After one day treatment 56 % of children reported complete relief of pain and after 7 days 62% reported the same. However, two children complained of increased pain 1 day after treatment. None of the children reported pain in the subsequent appointments. One child complained of tenderness in percussion after 6 months. Pulp canal obliteration was the most common change in the radiographic assessment. There was no significant difference between clinical (92.8%) and radiographic (90.4%) success (p=0.990).

Conclusion:

Pulpotomy using CEM cement could present a successful treatment in primary molar teeth with irreversible pulpitis.

Effect of laser preparation on adhesion of a self-adhesive flowable composite resin to primary teeth

The aim of the study was to evaluate the adhesion of a self-adhering flowable composite resin to primary tooth enamel and dentin after silicon carbide paper (SiC) and laser pretreatment. Adhesive properties were evaluated as shear bond strength (SBS) and scanning electron microscopic (SEM) characteristics. A total 120 primary canine teeth were randomly divided into two groups to study enamel and dentin. Each group was divided into 6 subgroups (n = 10) according to type of surface preparation (SiC or Er:YAG laser) of enamel or dentin. Three methods were used to build cylinders of restoration on tooth surface: OptiBond All-In-One + Premise Flowable composite, OptiBond All-In-One + Vertise Flow and Vertise flow. After restoration, samples were tested for SBS and failure mode. Twenty eight samples were examined by SEM. The results of the study showed SBS of Vertise Flow was lower than others in enamel and dentin samples pretreated with SiC and in dentin samples pretreated with laser (P < 0.001). Compared to SiC pretreatment, laser pretreatment led to a significantly higher SBS with Vertise Flow on enamel (P < 0.001). Vertise Flow associated with the adhesive led to a higher SBS in enamel and dentin compared to Vertise Flow alone. Adhesive and mixed failure modes were observed more frequently in Vertise Flow groups. SEM images showed that Vertise Flow led to more irregularities on enamel and more open dentinal tubules after laser ablation compared SiC pretreatment.

Assessment of simulated lesions on primary teeth with near-infrared imaging

Previous studies have demonstrated that the structural changes on enamel due to demineralization and remineralization can be exploited through optical imaging methods such as QLF, thermal and NIR imaging. The purpose of this study is to investigate whether PS-OCT and NIR reflectance imaging can be utilized to assess lesion structure in artificial enamel lesions on the smooth surfaces of primary teeth exposed to fluoride. The smooth coronal surfaces of primary teeth (n=25) were divided into 4 windows: sound, demineralization, demineralization with remineralization and APF with demineralization. Windows were treated with either acidulated phosphate fluoride (APF) for 1 minute, a demineralization solution for 4 days, and/or an acidic remineralization solution for 12 days. The samples were imaged using PS-OCT, QLF and NIR reflectance at 1400-1700 nm wavelengths. This study demonstrated that both PS-OCT and NIR reflectance imaging were suitable for assessing lesion structure in the smooth surfaces of primary dentition.

Trends in the prevalence of traumatic crown injuries and associated factors in Brazilian preschool children: 10-year observational data

OBJECTIVE

To assess trends in the prevalence of traumatic crown injuries (TCI) in children aged 1-4 years living in Diadema city (Brazil) and to investigate whether TCI were associated with socio-demographic and clinical variables.

METHODS

Six cross-sectional surveys with representative samples were carried out from 2002 to 2012 following the same criteria and methodology. A total of 6389 children were evaluated and systematically selected on the National Children's Vaccination day. Calibrated examiners performed the children's oral examination for TCI according to Andreasen's criteria. Chi-square test for trends was used to perform comparative analysis. Poisson regression was used to associate TCI to socio-demographic and clinical variables.

RESULTS

The prevalence of TCI in 2002 for preschool children aged 1, 2, 3 and 4 years was 4.5%, 11.4%, 14% and 13.9%, respectively, and the prevalence in 2012 for the same age groups was 10.4%, 15.9%, 25.7% and 28.1%, respectively. There was a significant increase in the prevalence of TCI for all age groups and for the total sample (P < 0.05). Children's age was associated with TCI in all the surveys. Male gender, presence of anterior open bite and inadequate lip coverage were associated with TCI in some surveys along the years (P < 0.05).

CONCLUSION

This study has shown an increase of TCI prevalence in Brazilian preschool children in the last 10 years and its association with children's age, male gender, presence of anterior open bite and inadequate lip coverage. However, this increase does not seem to be relevant to decisions on public policy.

Dentin Optical Density in Molars Subjected to Partial Carious Dentin Removal

AIM

This study aimed to evaluate changes in the optical density of dentin in primary molars with deep caries three to six months after they were subjected to partial carious dentin removal.

STUDY DESIGN

This was a blind controlled, clinical therapy study. Standardized digitalized bitewing radiographs of 42 teeth were analyzed using Adobe Photoshop(®) to quantitatively determine the gray scale of the affected dentin beneath the restoration, in comparison with healthy dentin. A mixed-effects model was used for statistical analysis. The gray tone level was considered a dependent variable; the tooth region and the time, in addition to the interaction between them, were the independent variables. Values of p < 0.05 were significant.

RESULTS

During the interval between time zero and three months, the gray tone levels of affected dentin varied from 80.99 ± 3.17 to 98.57 ± 3.17; i.e., an estimated increase of 18 (p < 0.0001). The values for healthy dentin ranged from 118.22 ± 3.17 to 122.02 ± 3.17; i.e., a mean increase of four in the gray tone levels (p = 0.0003). During the interval between three and six months, both healthy and affected dentin showed similar behavior (98.57 ± 3.17 to 103.32 ± 3.20 and 122.02 ± 3.7 to 126.56 ± 3.20, respectively) (p = 0.0001).

CONCLUSIONS

Significant increments were observed in the optical density of the affected dentin after three months compared to that of healthy dentin in primary molars treated using the partial carious dentin removal technique.

Adverse birth outcomes and childhood caries: a cohort study

OBJECTIVES

To examine the association between adverse birth outcomes and dental caries in primary teeth.

METHODS

This study included children in Khon Kaen, Thailand, who participated in the Prospective Cohort Study of Thai Children. Preterm was defined as a birth at <37 weeks gestation, low birthweight (LBW) as birthweight <2500 g, and small-for-gestational age (SGA) as birthweight <10th percentile of expected weight for gestational age. Two calibrated dentists measured dental caries in primary teeth when the children were 3-4 years old using decayed, missing and filled surfaces (dmfs) index following the World Health Organization criteria. We used negative binomial regression with generalize linear models to estimate relative risks (RRs) and their 95% confidence intervals (CIs), adjusted for confounding factors. Of 758 children with gestational age data and 833 with birthweight data, the 544 (follow-up rate of 71.8% in preterm and 65.3% in LBW) who had dental data available were included in the analysis.

RESULTS

Dental caries was observed in 480 children (88.2%), with a mean dmfs of 14.3 (standard deviation 12.8). The adjusted RR for dental caries was 0.61 (95% CI 0.43, 0.85) for preterm, 0.89 (95% CI 0.67, 1.21) for LBW, and 0.96 (95% CI 0.74, 1.26) for SGA.

CONCLUSIONS

There was an inverse association between preterm and childhood caries. LBW and SGA were not associated with dental caries in this population.

Fracture strength of restorations in proximal cavities of primary molars

This study evaluated the fracture strength of various restorative materials for primary molars in dovetail and box-only class II cavity designs. Eighty extracted noncarious human primary molars were used. The teeth were randomly divided into two groups for either dovetail or box-only preparations. The teeth were then divided into four subgroups for each restorative material: glass ionomer cement (GIC), resin-modified glass ionomer cement (RMGIC), compomer, and composite. The restorations were tested for fracture strength. The loads at fracture and fracture mode were recorded and a scanning electron microscopy analysis was performed to observe the micromorphology of the borders between the teeth and the materials. The nonparametric Kruskal-Wallis and Mann-Whitney U-tests were used. Although there were significant differences between the restorative materials (p < 0.05), there were no differences between the fracture strength of the box-only and the dovetail cavity designs in any of the groups (p > 0.05) except the composite group. The fracture strength of the compomer and composite groups was significantly higher than that of the GIC and RMGIC groups (p < 0.05). A class II cavity could be selected as dovetail or box-only and compomer and composite are more resistant to fracture than GIC and RMGIC.

Clinical and radiographic comparison of indirect pulp treatment using light-cured calcium silicate and mineral trioxide aggregate in primary molars: A randomized clinical trial

Aim:

To clinically and radiographically evaluate the reparative dentin formation in indirect pulp treatment (IPT) using mineral trioxide aggregate (MTA) and light cured calcium silicate (TheraCal) in primary molars over a period of 6 months.

Materials and Methods:

A clinical trial on IPT on 43 primary molars in 21 patients between the age of 4–7 years, divided into two groups: 22 teeth in MTA group and 21 in TheraCal group. Measurement of the variation in dentin thickness was done on the digitalized radiograph at baseline, 3 months and 6 months using CorelDRAW X3 software.

Results:

Statistical analysis using an independent t-test for intragroup and intergroup comparison showed a significant increase in dentin thickness in both the MTA and TheraCal group (intragroup comparison [P < 0.05]). However, intergroup comparison between MTA and TheraCal showed no statistical difference in reparative dentin formation (P > 0.05).

Conclusion:

Clinically and radiographically, both MTA and TheraCal are good IPT materials. The better handling characteristics and comparable reparative dentin-forming ability of TheraCal make this material an alternative to MTA in pediatric restorative procedures.

Advanced endodontic developments in pulpectomy of primary teeth

INTRODUCTION

To appraise studies about pulpectomy in primary teeth with nickel-titanium rotary files and smear layer removal and to find out may these developments enhance pulpectomy outcomes in primary teeth.

MATERIAL AND METHODS

A systematic search was implemented for PubMed, Google and Google Scholar between the years 1995-January 2016 to identify eligible studies. Studies design was established according to the CEBM recommendations. Evidence quality of studies was appraised by risk of bias.

RESULTS

Six studies about pulpectomy met the inclusion criteria, of which five were randomized controlled trials. Only one research demonstrates the enhanced outcome of pulpectomy in primary teeth with smear layer removal. Chosen studies have low overall evidence quality.

CONCLUSIONS

Given the paucity, high heterogeneity of high-quality articles and their level of bias, recommendation for the use of nickel-titanium rotary files and smear layer removal in pulpectomy in primary teeth can yet not be formulated.

Clinical Evaluation of Restorative Materials in Primary Teeth Class II Lesions

OBJECTIVE

The aim of this study was to evaluate clinical success of primary teeth class II lesions restored with different restorative materials [Hybrid Composite Resin (HCR), Resin Modified Glass Ionomer Cement (RMGIC), compomer, and Giomer Composite Resin (GCR)] followed up for 24 months.

STUDY DESIGN

This study was carried out on 146 primary molars of 41 children in the age range of 5-7 years. The class II lesions in primary molars of a patient were restored using different restorative materials. Restorations were evaluated according to FDI-criteria and their survival rates were determined. Data were analysed with Pearson chi-square, Kaplan-Meier and Wilcoxon (Breslow) tests (α = 0.05).

RESULTS

The failure rates of restorative materials were as follows: compomer 33.3%, RMGIC 28.1%, HCR 22.5% and GCR 21.1%.

CONCLUSIONS

While the functional failure was the most important factor in restorative material failure, RMGIC was the most successful material in terms of biological evaluation criterion and GCR had the longest survival rate.