What is the survival rate of deciduous molars in cases with agenesis of premolar successors? A systematic review

ABSTRACT Objectives To systematically review the literature on the survival rate of deciduous molars in cases of agenesis of premolar successors. Materials and Methods Four electronic databases and partial grey literature were searched up to November 2020. The PECOS eligibility criteria included (P) second deciduous molar (E) exposed to agenesis of a premolar successor (O) evaluated by the survival rate in the oral cavity, infraocclusion, and root resorption through (S) observational studies. Risk of bias (RoB) was assessed using the checklists from the Joanna Briggs Institute and the level of evidence was assessed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) tool. Results Three studies were included: one with low, one with moderate, and one with high RoB. Synthesis methods included the frequency of persistent deciduous second molars during the follow-up. Approximately 82% to 89% remained in the oral cavity after 5 to 13 years. The incidence of root resorption was 11%, and the infraocclusion was 1 mm. The level of evidence was considered low for each outcome. There was considerable RoB regarding the observational studies and a need for clinical and radiographic monitoring of the deciduous molars. Conclusions Maintaining a deciduous molar in the oral cavity in patients with agenesis of the premolar successor is a viable clinical choice since 82% to 89% of the retained molars evaluated were in good condition over a follow-up ranging from 5 to 13 years. Infraocclusion and root resorption did not seem to increase considerably. The level of evidence was considered low for each outcome.

Cantilever-Type Traction Appliance for Mandibular First Permanent Molars with Eruption Disturbances

Eruption disturbances of the mandibular first molars can cause multiple problems in occlusal development although they are extremely rare. Early diagnosis and treatment are very important to prevent complications associated with eruption disturbances. The present case report describes the treatment of two cases of eruption disturbances of the mandibular first permanent molar. A fixed appliance composed of a cantilever spring with mandibular second deciduous molar as an anchor tooth was used to tract the impacted mandibular first permanent molar. The success of both cases shows that this novel traction appliance can be used to induce the eruption of an impacted mandibular first permanent molar within a short time in patients with intact mandibular second deciduous molar as an anchor tooth.

Spatiotemporal Expression Patterns of Critical Genes Involved in FGF Signaling during Morphogenesis and Odontogenesis of Deciduous Molar in Miniature Pig

Background The fibroblast growth factor (FGF) pathway plays important role in epithelial-mesenchymal interactions during tooth development. However, how the ligands, receptors, and inhibitors of the FGF pathway get involved into the epithelial-mesenchymal interactions are largely unknown in miniature pigs, which can be used as large animal models for similar tooth anatomy and replacement patterns to humans. Results In this study, we investigated the spatiotemporal expression patterns of critical genes encoding FGF ligands, receptors, and inhibitors in the third deciduous molar of the miniature pig at the cap, early bell, and late bell stages. With the methods of fluorescence in situ hybridization and real time RT-PCR, it was revealed that the expression of Fgf3, Fgf4, Fgf7, and Fgf9 mRNAs were located mainly in the dental epithelium and underlying mesenchyme at the cap stage. The expression levels of Fgf3 and Fgf7 in the mesenchyme were upregulated in the early bell stage and then concentrated in the odontoblasts layer in the late bell stage. In contrast, the expression levels of Fgf4 and Fgf9 in the mesenchyme were downregulated from the cap to bell stage. Gene expression analysis also suggested that Fgfr1 and Fgfr3 were the major receptors regulating dental calcification. Furthermore, the inhibitor-coding genes Sprouty 2 and Sprouty 4 were expressed in the epithelium and mesenchyme in the three stages, indicating that elaborate regulation occurred during dental morphogenesis. Conclusions The spatiotemporal expression pattern of FGF signaling provides the foundation for future studies aiming to fine-tune dental morphogenesis and odontogenesis by controlling the interactions between the dental epithelium and mesenchyme, thereby promoting tooth regeneration in large mammals.

Developmental hypomineralization of the enamel of the first permanent and the second deciduous molars - report of two cases

Introduction. Molar-incisor hypomineralisation (MIH) is a developmental defect of dental enamel that affects one to all four first permanent molars (FPM) and frequently permanent incisors. Enamel aberrations are observed as demarcated opacities of different colours (from white to brown) and as posteruptive enamel breakdown (PEB). Clinically similar pathological signs can also be present in deciduous molars. Case outline. Histology of an FPM and a second deciduous molar (SDM) was performed after extraction from two unrelated patients with MIH due to inflammatory complications. Tooth samples were analysed using a stereomicroscope (SM), light microscope (LM) and scanning electron microscope (SEM). Enamel thickness of both affected teeth was normal. An obvious distinction in enamel microstructure was observed between the normally developed and the MIH-hypomineralised enamel with SM, LM, and SEM. Conclusion. In MIH patients, regular dental visits enable early diagnosis of the disease and appropriate treatment of the patient as soon as possible, with included preventive measures.

Rare Case of Unerupted Second Deciduous Molar with Congenitally Missing Second Permanent Premolar: Case Report

SummaryBackground/Aim: The purpose of this report is to present an unusual case of failure of eruption of a second deciduous molar and its management.Case Report: An 8-year-old boy presented with a complaint of a missing tooth. Radiographic examination revealed the second deciduous molar was impacted without any mechanical obstacles, like an odontoma or supernumerary teeth, being present.Conclusions: The case presented in this report is of scientific relevance due to the rarity of this type of pathology and the interesting histopathology.

Willet’s distal shoe appliance for early loss of second deciduous molar: A case report with 2 year follow up

The possibilities for space loss are even higher when second primary molars are lost early because they serve as a buttress for the eruption of first permanent molar. Distal shoe space maintainer is indicated in such type of cases. It is otherwise known as intra-alveolar appliance. In this article, we report the successful use of the distal shoe space maintainer in a 4yr old child.

Massive Radicular Cyst in the Maxillary Sinus as a Result of Deciduous Molar Tooth Pulp Necrosis

The article describes a rare case of radicular cyst associated with deciduous right upper molars in a 5 y.o. male patient. The cyst developed asymptomatically in the maxillary sinus, thus causing considerable displacement of both premolar germs. Due to the severity of surgery, the patient was treated under general anesthesia in a one-day surgery system with use of the enucleation method. The extent of the lesion results in necessity of removal of the second premolar germ. Early diagnosis of the lesion would have resulted in a more conservative treatment plan. The purpose of this article is to lay emphasis on the pedodontist’s role in early diagnosis of such lesions.