Role of impacted teeth in dental arch crowding

Estimates show that the prevalence of mandibular dental anterior crowding is high and might be up to 40%. The etiology of the condition has been multifactorial and evidence regarding the impact of mandibular third molars is still controversial. We discussed the potential role that impacted teeth (particularly mandibular third molars) might have in developing dental arch crowding. Evidence from different original studies and reviews regarding the impact of lower third molars on dental crowding was controversial. However, most of these studies showed that the correlation between these events was insignificant and additional studies might be needed for further validation. We have also identified many factors that can lead to dental arch crowding among the relevant studies in the literature. These factors might include general factors (including gender and age), skeletal factors (including malocclusion and growth of jaws) and dental factors (including primary tooth loss and tooth crown size), all of which were extensively discussed in the current study. Accordingly, further attention should also be paid to studying these factors.

Developmental Dental Defects in Permanent Teeth Resulting from Trauma in Primary Dentition. A Systematic Review

The objective was to determine whether trauma in primary dentition causes alterations in the development of permanent dentition. Searches were made in May 2020 using PubMed, MEDLINE, MEDES, Scopus, Lilacs, and Embase. Papers in English, German, and Spanish, without restrictions in the year of publication, were included. The quality of the studies was analyzed using the NOS Scale. The search retrieved 537 references, and seven studies were included for a qualitative analysis. The results showed that trauma to a deciduous tooth can damage the bud of the permanent tooth. Enamel discoloration and/or hypoplasia were the most common sequelae in the permanent teeth after trauma to the primary predecessor. The type and severity of sequelae in the permanent tooth are associated with the development phase of the bud. Children with trauma of their primary teeth should receive checkups until the eruption of the permanent teeth for the early diagnosis and treatment of possible sequelae. Intrusion of the primary tooth was the trauma that caused the most damage and enamel alterations the most frequent sequelae.

Difference in Bonding Strength of RMGIC according to Type of Hemostatic Agent in Primary Tooth

The purpose of this study was to compare the effect of the hemostatic agent containing aluminum chloride with hemostatic agent containing ferric sulfate on the shear bond strength of resin-modified glass ionomer cement(RMGIC) to dentin in primary tooth. Twenty extracted non-carious human primary teeth were collected in this study. The specimens were cut to expose dentin and polished. The specimens were randomly seperated into 3 groups for treatment; group I: polyacrylic acid(PAA), RMGIC; group II: aluminum chloride, PAA, RMGIC; group III: ferric sulfate, PAA, RMGIC Ten specimens from each group were subjected to shear bond strength test. The mean shear bond strength of each group was as follows: 10.07 ± 1.83 MPa in Group I, 7.62 ± 0.78 MPA in group II, 5.23 ± 0.78 MPa in group III. There were significant differences among all groups(p < 0.001). In conclusion, both aluminum chloride hemostatic agent and ferric sulfate hemostatic agent decreased the shear bond strength of RMGIC to dentin. And ferric sulfate hemostatic agent decreased the shear bond strength of RMGIC more than the aluminium chloride hemostatic agent.

Pediatric Rotary Files: Evolution to Revolution

The main goal of pulp therapy in primary dentition is to preserve the primary tooth thus protecting future normal occlusion. Routinely, pulp debridement and canal shaping are done by manual H-files, K-files, Broach, etc. Manual instrumentation may be time- consuming, thus impacting the behaviour of the child negatively. Thus arises the need for alternate instrumentation which will reduce the time required for treatment with better treatment outcomes. In 1988, Walia et al. introduced Nickel-Titanium (Ni-Ti), which revolutionized the discipline of Endodontics. These Ni-Ti files have advantage of shape memory and super elasticity thus improving the canal preparation and resulting in better shaped canals. In 2002, for first time Barr et al reported the use of rotary Ni-Ti files for the therapeutic purpose during Pulpectomy procedure in pediatric patient. He observed better acceptance by pediatric patient and good quality obturation. Till 2016, pulpectomy procedures were accomplished by the combination of hand files and adult rotary files. Adult rotary files are designed according to the morphology for permanent teeth and adult jaw size, thus the use of adult rotary files are in primary teeth may result in lateral perforation due to softer dentine of roots of primary teeth and may cause discomfort to the child thus making child unco-operative. But in 2016, Ganesh et al., pioneered the specialization of Paediatric Endodontics with his invention of specially designed rotary files. Their shape was specially designated for application in tortuous canals of primary teeth. Presently, a variety of pediatric rotary files like Kedo-STM (India), Pro AF Baby GoldTM (India),PrimePedoTM (India), DXL-ProPedoTM (India), NeolixTM (France),Denco® Kids files (China) and, Sani® Kid rotary files (China). This review is an album of these newer files and clinical and in-vitro research on them.

Management of Crossbite in Anterior Region Due to Over-retained Deciduous Teeth in an Adolescent – a Case Report

The deciduous teeth which are retained beyond the age of exfoliation are termed as over-retained deciduous teeth. There are numerous reasons for such teeth which include congenital absence or impaction or translation or transmigration of successor teeth or maybe because of existence of some kind of pathology, such as cysts, tumours, and odontoma under the primary tooth that results in the impaction of successor teeth. It may also be due to partial or total microdontia of permanent dentition. This leads to malalignment in permanent dentition which indirectly hampers the normal growth of the jaws. This case report shows several after-effects of over retained teeth along with the concerned multiple treatment options.

Evaluation and Comparison of Formocresol and Sodium Hypochlorite as Pulpotomy Medicaments in Treatment of Mandibular Primary Molars - A Randomized Controlled Study

Background: the main idea behind the pulpotomy of a primary tooth is to remove the infected or inflamed coronal pulp tissues and cover the pulp with a suitable medicament or dressing which promotes healing and preserve the vitality of the teeth especially in young permanent teeth. A medicament should be biologically compatible, have healing capabilities, should be non cytotoxic, or mutagenic and with no carcinogenic potential. Aim: the main aim of the study was to compare and evaluate the efficacy of commonly used two medicaments i.e. formocresol and sodium hypochlorite in pulpotomy of mandibular primary teeth. Material and methodology: a randomized controlled single blinded clinical trial was done on 50 subjects of age ranging from 3 to 6 years with bilateral mandibular first or second molar requiring pulpotomy. The subjects were randomly divided into two groups with 25 subjects in each. Group I, consisted of subjects on which formocresol medicament was used after extirpation of coronal pulp while in Group II, 3% sodium hypochlorite was used. Clinical along with the radiographic signs and symptoms were blindly recorded at an interval of 1, 3, 6 and 12 months respectively. Results: Statistically significant results were obtained in group II, when patients treated with 3% sodium hypochlorite. There was no major difference between the two medicaments used, but to the various adverse effects of formocresol, its usage has been limited. Conclusion: within the limitation of the study, it was concluded that sodium hypochlorite medicament proved to have better prognosis and can be suggested as a pulpotomy agent for primary teeth. Although formocresol was found to have similar significant results can also be used as a medicament. Keywords: Formocresol, Pulpotomy, Primary Teeth, Sodium Hypochlorite

Experimental Validations of Hybrid Excited Linear Flux Switching Machine

Linear Flux Switching Machines (LFSMs) possess the capability to generate adhesive thrust force, thus problems associated with conventional rotatory electric machines and mechanical conversion assemblies can be eliminated. Additionally, the unique features of high force/power density, efficiency, and a robust secondary structure make LFSMs a suitable candidate for linear motion applications. However, deficiency of controllable air-gap flux, risk of PM demagnetization, and increasing cost of rare earth PM materials in case of PMLFSMs, and inherent low thrust force capability of Field Excited LFSMs compels researchers to investigate new hybrid topologies. In this paper, a novel Double-Sided Hybrid Excited LFSM (DSHELFSM) with all three excitation sources, i.e., PMs, DC, and AC windings confined to short moving primary and segmented secondary providing short flux paths is designed, investigated, and optimized. Secondly, unequal primary tooth width optimization and additional end-teeth at all four corners of the primary equip proposed design with balanced magnetic circuit and reduced end-effect and thrust force ripples. Thirdly, the measured experimental results of the manufactured proposed machine prototype are compared with corresponding simulated model results and shows good agreements, thus validating the theoretical study.

Evaluation of Knowledge and Attitude of Kindergarten Teachers about Primary Tooth Trauma in Khorramabad City

Introduction: Injury to both the primary and permanent dentitions is one of the most common dental problems. The prognosis of dental trauma depends on the basic measures taken immediately after trauma. This study was designed to assess the level of knowledge, the attitude of kindergarten coaches about primary teeth trauma in Khorramabad city. Materials & Methods: In this Cross-sectional study, 100 kindergarten coaches in Khorramabad participated in this study in 2019-2020. A valid and reliable confirmed questionnaire was used for data collection. Data were analyzed with Pearson correlation coefficients and independent t-test (p value < 0.05). Results: In this study, the mean score of coaches’ attitude was 68.5 and the mean score of knowledge was 34.9. In the present study, the factors of gender, age, level of education had no significant relationship with their knowledge score (p value > 0.05) and attitude, but between work experience with knowledge scores (p value = 0.02) and attitude (p value = 0.004) and so between the level of knowledge (p value = 0.004) and attitude (p value = 0.008) and passing the dental emergency training course, a direct relationship was observed. In this study, there was a significant relationship 64% of the coaches experienced dental trauma and their mean score of knowledge (p value = 0.04) and attitude (p value = 0.001) was significantly higher than other coaches. Conclusion: The assessed level of dental knowledge of the coaches participating in this study was poor, whereas their attitude about primary tooth trauma was good. The great suggestion is to hold educational programs in this regard to increase the level of knowledge of kindergarten coaches in the field of dental trauma.

Comparação clínica e radiológica de pulpotomia em dentes decíduos com formocresol, MTA e biodentine

Introdução: O processo de pulpotomia convencionalmente é feito com formocresol, porém, devido as suas características mutagênicas, novos materiais obturadores foram desenvolvidos como alternativa. Objetivo: Revisar a literatura de forma integrativa a respeito do material obturador mais adequado para pulpotomia de dentes decíduos. Metodologia: A busca ocorreu nas bases de dados Pubmed e Medline, por meio dos descritores: “child”, “children”, “primary teeth”, “tooth, deciduous”, “primary tooth”, "pulpotomy", "pediatric dentistry", "endodontics", "root canal filling materials", "materials", "material", "biodentine", "mineral trioxide aggregate", "formocresol", "formocresols", "cytotoxicity", "biocompatible materials", "biocompatibility", "radiopacity", "radiographic" e "radiography, dental". Foram incluídos ensaios clínicos, estudos retrospectivos e estudos prospectivos, publicados entre 2016 e 2021, em inglês ou português. Os critérios de exclusão foram teses, dissertações, monografias, cartas ao editor, livros e revisões de literatura. Resultados: A pesquisa resultou em 9 estudos de ambas as bases de dados, com maior prevalência de ensaios clínicos. Conclusão: O material mais recomendado para realização de pulpotomias em dentes decíduos é o Biodentine e Mineral Trioxide Aggregate, devendo a escolha ser feita de acordo com o critério do profissional e caso do paciente. É preciso que seja considerado os custos e colaboração do paciente durante o tratamento.