Clinical and radiographic performance of preformed zirconia crowns and stainless-steel crowns in permanent first molars: 18-month results of a prospective, randomized trial

Efficacy evaluation of zirconia crown on primary molars with caries defects

OBJECTIVES

This study aimed to estimate the therapeutic effects of preformed metal crown (PMC) and prefabricated zirconia crowns (ZC) on decayed primary morals in children, as well as to analyze the possible influencing factors.

METHODS

A retrospective cohort study was performed on the data of 192 patients (aged 3 to 8) in the Stomatological Department of Shenzhen Children's Hospital from October 2021 to December 2021. The decayed mandibular first molars were selected and restored by vital-pulp therapy followed by PMC and ZC, including 96 cases (96 caries) in the PMC group and 96 cases (96 caries) in the ZC group. Oral clinical examination was performed at 3 months, 1 year, and 2 years after treatment, overwiewing the clinical therapeutic effects and periodontal status of PMC and ZC groups, as well as recording the crown integrity, gingival index (GI), probing bleeding index (BI), plaque index (PLI) and various prosthetic indices.

RESULTS

No significance differences existed in the periodontal status of PMC and ZC groups at 3 months, 1 year, and 2 years after treatment (P>0.05). However, the GI, BI, and PLI in the PMC group were higher than those in the ZC group at 3 months, 1 year, and 2 years after treatment, and the difference was dramatically significant (P<0.05). No significances difference existed in various prosthetic indices (P>0.05), as well as in the GI, BI, and PLI, between the two groups (P>0.05). No significant differences existed in various prosthetic indices between genders after PMC restoration (P>0.05). The scores of girls in various prosthetic indices after ZC restoration were higher than those of boys (P<0.05). Pearson correlation analysis indicated an inverse correlation between age in the PMC group and the GI, BI, PLI, and FDI indices (P<0.01), rather than in the ZC group (P>0.05).

CONCLUSIONS

PMC and ZC can be applied to restore deciduous molar caries. The periodontal status of deciduous teeth in ZC group was superior to that in the PMC group. The periodontal status of deciduous teeth in PMC group may be stable with increased age.

Stress Distribution of Pediatric Zirconia and Stainless Steel Crowns after Pulpotomy Procedure under Vertical Loading: A Patient-Specific Finite Element Analysis

Aim: With modern dentistry advancements, children and parents have significantly raised aesthetic expectations in pediatric dentistry. Pediatric zirconia crowns (PZCs) provide a superior aesthetic appearance compared with stainless steel crowns (SSCs), making them a popular treatment option. However, a comparison of the compressive stresses caused by these crowns on the roots of primary teeth and alveolar bones has not been conducted. Materials and Methods: Cone beam computed tomography (CBCT) images of an eight-year-old female patient who experienced premature loss of a primary mandibular left second molar were obtained from a dental hospital database. Rhinoceros 4.0 software was used to process and simulate images. Under simulated chewing forces, stress on the PZC, SSC, and intact primary first molars as control groups, as well as their roots and alveolar bone structures, was assessed with finite element analysis. Statistical Analyses: Depending on whether the descriptive data were normally distributed, the Student t-test and Mann-Whitney U test were used. Quantitative variables differ between the two categories of qualitative variables. One-way ANOVA and Kruskal-Wallis H tests were used depending on standard distribution assumptions. p < 0.05 indicates statistical significance differences. Results: PZCs, SSCs, and cement layers were stressed according to von Mises values, while roots and alveolar bones were stressed according to maximum and minimum stress values. When assessing crowns, SSCs exhibited the highest von Mises stress values, followed by PZCs and control groups (p < 0.001). In the cement layer, SSCs obtained significantly higher values (p = 0.003). In the root area, minimum principal stress values are more critical. The highest values were obtained from the intact tooth, PZC, and SSC, respectively (p < 0.001). Alveolar bones did not differ significantly in minimum principal stress (p = 0.950). Conclusions: Restorative full-coverage crowns exhibited higher von Mises values than intact teeth, as per current research findings. The von Mises values were highest in SSC, while lowest in PZC. As a result of this condition, the cement layer and root areas had higher von Mises stress and compressive stress. Alveolar bones were not affected regardless of restoration type. PZC transmits higher stress due to its properties.

Treatment Alternative of Molar Incisor Hypomineralisation for Young Permanent Teeth: A Scoping Review

Background

Treatment of Molar-incisor hypomineralisation (MIH) poses significant challenges for pediatric dentists due to its varied clinical manifestations and treatment needs. Understanding and evaluating different treatment options can improve patient outcomes. This study aimed to analyze available evidence on treatment options for restoring MIH-affected young permanent teeth.

Methods

This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. A systematic literature search was conducted using Scopus, PubMed, and Science Direct databases, covering publications from 2014 to 2024. The search focused on therapies for young permanent teeth with MIH in children, employing predefined keywords and the Population, Concept, and Context framework.

Results

A total of 20 studies were included from Turkiye, Brazil, Syria, Germany, Egypt, and India. Thirteen articles examined first molars, five focused on incisors, and two covered both. The population studied ranged from 6 to 18 years old, involving up to 281 children and between 30 to 326 teeth. The study provides insights into various management and treatment approaches for MIH-affected teeth, along with the effectiveness and long-term stability of different methods and materials.

Conclusion

Materials such as resin infiltration, SDF, HVGI, full metal crowns, SSC, lithium disilicate, zirconia crowns, and CAD/CAM ceramic restorations offer greater longevity and require less retreatment in managing MIH-affected teeth.

Prefabricated Zirconia Crowns and Preformed Metal Crowns in the Treatment of Severely Childhood Caries and Anterior Crossbite in a Child with Autistic Spectrum Disorder

Crowns have been recommended to treat decayed teeth and rebuild teeth function. The dental management of children with autism is a tremendous challenge for pediatric dentists due to the impaired behaviors and communication disorders. In this context, a 5-year-old boy with autism was treated to solve carious lesions under the assistance of general anesthesia. The posterior occlusal function was restored, and the crossbite existing in the primary anterior teeth was approached merely by NuSmile® zirconia crowns (ZCs) rather than orthodontic intervention. We conducted an 18-month period. Throughout the long-term follow-up, the boy's masticatory efficiency was remarkably improved and the anterior teeth had transferred into the correct position with adequate overbite to maintain the new relationship, thus ameliorating the appearance of tissue on the labial surface and enhancing his quality of life and oral health.

[Need for prosthodontics of permanent teeth in children aged 8-18 years]

OBJECTIVE

To reveal need for prosthodontics in permanent teeth in children aged 8-18 years.

MATERIALS AND METHODS

The study was performed in Khimki Dental Municipal Clinic. Dental examination and radiological studies were conducted in 97 primary patients aged 8-18 years. Indications for prosthodontics in permanent teeth were occlusal deterioration index more than 40% and crown decay of more than 50% in incisors and canines. Additional features were registered including DMFT index, the presence of extracted teeth and teeth after root canal treatment, as well and teeth with extensive restorations with resins and marginal seal quality.

RESULTS

From 97 primary patients (27.8%) children needed prosthodontics in permanent teeth (in average 2.3±2.1 teeth): 1 tooth in 10 children, 2 teeth in 11 children, 3 teeth in 1 child, 4 teeth in 3 children and 4 teeth in 2 children. Mean DMFT was 8.1±4.5 teeth. Six children already had extracted permanent teeth (9 teeth in total). Half of the teeth (49.2%) which needed orthodontic treatment had history of root canal treatment while 46% needed primary or secondary endodontic treatment. Occlusal deterioration index was more than 40% in 41.3% of cases, more than 60% in 49.2% of teeth and more than 80% in 9.52% of teeth. From all the teeth restored with composite resins 41.7% had good marginal seal but 58.3% showed macroscopic signs of marginal leakage.

CONCLUSION

Our study shows high percentage of adolescents having need for prosthodontics in permanent teeth and unjustified widening of indications for direct resin restorations in this group of patients.