Evaluation of Clinical Success, Parental and Child Satisfaction of Stainless Steel Crowns and Zirconia Crowns in Primary Molars

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.

Evaluation of Microleakage Using Different Luting Cements in Kedo Zirconia Crowns: An In Vitro Assessment

Introduction A space between the prepared tooth and the cemented crown can cause microleakage, allowing microorganisms to enter, which in turn leads to the breakdown of the luting cement. To achieve an optimum fit, several factors should be considered, including the type of crown used, the taper of tooth preparation, and the type of cementing agent. Aim The purpose of the current study is to evaluate the microleakage of zirconia crowns cemented with glass ionomer cement (GIC), resin-modified GIC (RMGIC), and self-adhesive resin cement. Materials Forty-five primary mandibular molars were divided into three groups: Group I receiving GIC, Group II receiving RMGIC, and Group III receiving self-adhesive resin cement. These cements were used to lute the teeth with Kedo zirconia crowns. The restored samples underwent thermal cycling and were assessed for microleakage under a stereomicroscope. For the statistical analysis, SPSS version 23.0 was used. Descriptive statistics were presented as frequencies and percentages. Analytical statistics, including the Mann Whitney U test, were used to assess the differences in the level of microleakage between the groups at p < 0.05. Results The Mann Whitney U test revealed no significant difference in the level of microleakage between GIC and RMGIC (p = 0.072). However, self-adhesive resin cement showed significantly less microleakage than GIC (p = 0.000). Similarly, when comparing RMGIC and self-adhesive resin cement, the latter showed significantly less microleakage than the former (p = 0.001). Conclusion Microleakage of Kedo zirconia crowns on mandibular first molars was highest when luted with GIC, followed by RMGIC, and was least when luted with self-adhesive resin cement.

Custom-made versus prefabricated zirconia crowns for primary molars: A 12-month follow-up

BACKGROUND

Many practitioners have questioned whether the construction method of pediatric zirconia crowns impacts the periodontal health and clinical performance of severely decayed primary molars. The objective of this study was to compare the periodontal health and clinical performance of primary molars restored with custom-made zirconia crowns (CZCs) and prefabricated zirconia crowns.

METHODS

Twenty primary molars indicated for crown restorations were selected from ten patients (5-9 years old) randomly. Each patient received two pediatric zirconia crowns constructed by two different methods: one custom-made and one prefabricated. The primary molars were divided into two groups: Group 1: primary molars received CZCs and Group 2: primary molars received prefabricated zirconia crowns (PZCs).

RESULTS

After a 12-month follow-up, there was no statistically significant difference between the periodontal health of primary molars restored with custom-made and prefabricated zirconia crowns. The clinical performance of primary molars restored with CZCs was statistically significantly higher than those restored with PZCs in terms of retention and fracture resistance (P ≤ 0.05).

CONCLUSIONS

The construction method of pediatric zirconia crowns does not significantly affect the periodontal health of primary molars; however, clinical performance is significantly affected in terms of retention and fracture resistance.

CLINICAL SIGNIFICANCE

A CZC is an excellent alternative option, especially for primary molars whose permanent successors still have a long time to erupt. The PZC is a quick and easy restoration, but the technique is sensitive.

Fracture resistance evaluation of CAD/CAM zirconia and composite primary molar crowns with different occlusal thicknesses

OBJECTIVE

To evaluate the effect of different CAD/CAM materials and occlusal thicknesses on the fracture resistance of primary molar crowns.

METHODS

Sixty extracted primary molar teeth were prepared and randomly divided into six experimental groups according to the material and thickness. Primary molar crowns with a central groove thickness of 0.3 and 0.5 mm were fabricated from CAD/CAM zirconia (group Z), zirconia-reinforced lithium silicate (group ZLS), and pre-polymerized composite resin blocks (group C). Each crown was cemented with self-adhesive resin cement on the prepared tooth. All specimens were subjected to fracture tests until fracture. Fracture load values were recorded in Newtons (N). Data were statistically analyzed using a two-way analysis of variance (ANOVA) followed by Tukey multiple comparison test.

RESULTS

The highest fracture load values were obtained in group Z at 0.5 mm occlusal thickness and were significantly higher compared with the other experimental groups (p < 0.05). Although the lowest fracture load values were obtained in group ZLS at 0.3 mm occlusal thickness, all the tested CAD/CAM primary molar crowns at both thicknesses demonstrated fracture load values exceeding reported chewing force in pediatric patients.

CONCLUSION

CAD/CAM primary molar crowns with reduced occlusal thickness may be used for the full-coverage restoration of primary molar teeth.

Evaluation of Changes in Oral Microflora in Children with Early Childhood Caries after Full Mouth Rehabilitation

Aim

To evaluate the change in microflora in children suffering from severe early childhood caries (ECC) after full mouth rehabilitation.

Materials and methods

A total of 60 children, aged 3-5 years suffering from severe ECC who fulfilled the inclusion and exclusion criteria were included in the study. Pooled plaque samples were taken and subjected to quantitative reverse transcriptase polymerase chain reaction (PCR) to obtain baseline mean values of Streptococcus mutans (S. mutans), Streptococcus sobrinus (S. sobrinus), Candida albicans (C. albicans), and Candida dubliniensis (C. dubliniensis) before full mouth rehabilitation was done under general anesthesia. Posttreatment samples were collected at 6, 12, and 18 months. Wilcoxon signed-rank test was used to compare the mean values of S. mutans, S. sobrinus, C. albicans, and C. dubliniensis before and after full mouth rehabilitation.

Results

A total of 60 patients recruited for the study were present at the follow-up at 6 and 12 months. At 18 months, 55 patients returned, and five were lost due to follow-up. A statistically significant reduction was seen in all microorganisms at 6, 12, and 18 months compared to baseline values. At 18 months a slight increase in S. mutans, S. sobrinus, and C. albicans was seen. C. dubliniensis was not detected in any cases after full mouth rehabilitation. Caries recurrence was seen in four patients at 18 months.

Conclusion

Significant reduction of S. mutans, S. sobrinus, C. albicans, and C. dubliniensis was seen at 6, 12, and 18 months. A complete reduction of only C. dubliniensis was seen. A significant but not permanent reduction of S. mutans, S. sobrinus, and C. albicans. Caries recurrence was seen in 7.27% of patients at 18 months.

How to cite this article

Mathew MG, Jeevanandan G, Rathod NN. Evaluation of Changes in Oral Microflora in Children with Early Childhood Caries after Full Mouth Rehabilitation. Int J Clin Pediatr Dent 2024;17(1):21-25.

Comparative evaluation of clinical performance, child and parental satisfaction of Bioflx, zirconia and stainless steel crowns in pediatric patients

Background

Pediatric dental treatment is challenging in patients with early childhood caries. For clinician its difficult to manage child and provide good work at the same time. Its necessity to have the best equipments as well as materials. Nowadays, aesthetics play an important role in managing decayed teeth. Zirconia crown is better option but requires excessive preparation. As Bioflx is newly developed crown and has combined stainless steel and zirconia properties.

Aim

To assess the clinical performance and child and parental satisfaction of Bioflex crowns compared to zirconia and stainless steel crowns.

Methods

In this comparative study of Bioflx crowns with zirconia and stainless steel crowns, children aged three to seven years old will be selected, and 72 primary teeth requiring crowns will be randomly distributed into three groups, n = 24: Group I: Preformed stainless steel crown, control; Group II: Preformed Bioflex crown; Group III: Preformed zirconia crown. Crowns will be evaluated for recurrent caries, plaque accumulation, restoration failure, gingival status opposing tooth wear, and clinicians and parental satisfaction at zero, three, six, and 12 months.

Results

Bioflx crown will have better clinical as well as parental satisfaction among zirconia and stainless steel crowns.

Conclusions

The Bioflx crown can be used as an alternative economical esthetic full-coronal restoration for primary teeth.

Trial registration

CTRI registration number: CTRI/2023/05/052256; Date of registration: May 03, 2023.

Protocol version

Two; Date: April 22, 2023.

Evaluation of Clinical Success, Caries Recurrence, and Oral Health-Related Quality of Life of Children Undergoing Full Mouth Rehabilitation for Early Childhood Caries: A Prospective Cohort Study

AIM

This prospective cohort study aimed to assess the clinical success, caries recurrence, and oral health-related quality of life of children undergoing full mouth rehabilitation for early childhood caries under general anesthesia. The study sought to understand the long-term impact of these interventions on early childhood caries (ECC) management.

METHODOLOGY

The study included 300 children aged three to six years diagnosed with ECC requiring full mouth rehabilitation under general anesthesia. The assessment included clinical success of various dental treatments, caries recurrence rates, and oral health-related quality of life using the Early Child Oral Health Impact Scale at baseline, 12 months, and 24 months post-treatment. Specialized caries preventive protocols were implemented, including education on oral hygiene, reminders, and nutritional guidance.

RESULTS

272 children attended the 12-month follow-up, out of which 11 children had new carious lesions. Two hundred fifty-two children were reported for the 24-month follow-up, in which 19 children reported new carious lesions. The clinical success rate of treatment was found to be high. The oral health-related quality of life showed a significant and sustained improvement from baseline to 12 months and further improvement at 24 months post-treatment.

CONCLUSION

Full mouth rehabilitation under general anesthesia is an effective approach for managing ECC in young children, with high clinical success rates and significant improvements in the oral health-related quality of life over two years. Preventive oral health strategies are necessary to maintain these positive outcomes and improve the overall well-being of affected children.

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

BACKGROUND

The treatment of young permanent first molars with extensive carious tissue loss may often require restoration with preformed crowns. This study compared the clinical and radiographic performance of stainless-steel crowns (SSCs) and preformed zirconia crowns (ZCs).

METHODS

Forty-eight molar incisor hypomineralisation (MIH)- or caries-affected permanent molars in 20 healthy patients between 6-13-year-old were randomly divided into ZC and SSC groups (n = 24 teeth/group) in a split-mouth design. The oral hygiene levels of patients were assessed using Greene and Vermillion simplified oral hygiene index (OHI-S). Plaque accumulation and gingival health were evaluated using the Silness&Löe plaque index (PI) and Löe&Silness gingival index (GI), respectively. Clinical retention, marginal extension level, marginal adaptation of crowns and wear of the antagonist teeth were assessed at baseline, 1, 6, 12 and 18 months. The radiological assessments for evaluating the marginal adaptation of crowns and periapical pathology of crowned teeth were performed at 6 and 12 months. The data were analyzed using Kaplan-Meier analysis, Mann-Whitney U test, and two-way ANOVA.

RESULTS

A total of forty teeth in 17 children were evaluated for 18 months. ZCs had significantly lower gingival and plaque index values than teeth restored with SSCs during all evaluation periods (p < 0.05). Neither crown type resulted in clinically-detectable wear on opposing dentition or periapical pathology. One ZC was lost at 13 months, while all SSCs survived in function clinically. The cumulative survival rates of ZCs and SSCs were 95.2% and 100% respectively.

CONCLUSIONS

Both ZCs and SSCs showed high clinical retention rates in young permanent molars. ZCs had lower plaque accumulation and better gingival health than SSCs, which were consistently associated with mild gingival inflammation.

CLINICAL TRIAL REGISTRATION NUMBER

NCT05049694.

Clinical Evaluation of Maneuverability and Durability of Titanium Nitride-coated Preformed Crown on Primary Molar Teeth: A Randomized Controlled Trial

Background

The management of multisurface carious primary molar is challenging. Currently, the ideal choice for the management of extensive multi-surface carious primary molar is the placement of a preformed stainlesssteel crown (SSC)/preformed zirconia crown. Unfortunately, conventional preformed SSCs are frequently refused by parents for esthetic reasons, while the preformed zirconia crown has its own disadvantages like high cost and excessive tooth preparation.

Aim

To evaluate the maneuverability and durability of titanium nitride-coated crowns on primary molar teeth and to assess the child-parent satisfaction of titanium nitride-coated gold-colored preformed crowns over metal-colored preformed SSC on primary molar teeth.

Materials and methods

Randomized controlled trial conducted on children between the age-groups of 6- and 9-year-old children. Group I for titanium nitride-coated preformed crown and group II for preformed SSC (control group) were allotted with a simple random technique. The maneuverability of the titanium nitride-coated crowns was evaluated in comparison with preformed SSC in terms of the level of difficulty while trimming, contouring, crimping, and wearing out of titanium nitride coating while manipulating. Participants of group I were recalled for follow-up in the 1st, 6th, and 12th months to evaluate the durability of the titanium nitride coating on the preformed crowns.

Results

There were no failures at the 12-month follow-up in terms of the durability of the titanium nitride coating, and there was no significant difference seen in terms of the maneuverability of both crowns. Overall, child-parent satisfaction was good with gold-colored titanium nitride-coated crowns.

Conclusion

The study concluded that titanium nitride-coated gold crowns could be a boon to pediatric dentistry and serve as an alternative to metal-colored SSCs.

How to cite this article

Vundela RR, Gupta N, Balamurugan S, et al. Clinical Evaluation of Maneuverability and Durability of Titanium Nitride-coated Preformed Crown on Primary Molar Teeth: A Randomized Controlled Trial. Int J Clin Pediatr Dent 2023;16(S-3):S263-S267.

Perceived Outcomes, Parental Satisfaction, and Oral Health-Related Quality of Life After Full Mouth Rehabilitation Under General Anesthesia for Early Childhood Caries

AIM

The aim of this article is to evaluate the perceived outcomes, parental satisfaction, and oral health-related quality of life after full mouth rehabilitation under general anesthesia for children with early childhood caries.

MATERIALS AND METHODS

A total of 200 children requiring full-mouth rehabilitation under general anesthesia for the management of early childhood caries were recruited for the study. Perceived outcomes, oral health-related quality of life, and parental satisfaction were evaluated at the follow-up visit after six months.

RESULTS

All participants reported back for the follow-up visit after six months. Oral health-related quality of life after full-mouth rehabilitation showed statistically significant improvement at follow-up (P <0.001); 97.5% of the parents were satisfied with the treatment. Perceived outcomes were found to be satisfactory, and a significant improvement (P <0.001) was seen after treatment.

CONCLUSION

The perceived outcomes of participating parents were met. Significant improvement in oral health was seen after full-mouth rehabilitation under general anesthesia. Parental satisfaction was found to be high at the follow-up visit after six months. Parents found the improvement in the oral and general health of their child to be significant.

The Evaluation of Postoperative Complications and Oral Health-Related Quality of Life Following Dental General Anesthesia for Early Childhood Caries

Aim The study aims to evaluate the postoperative complications and oral health-related quality of life (OHRQoL) following dental general anesthesia for early childhood caries (ECC). Materials and methods Two hundred children aged between three and six requiring full-mouth rehabilitation for general anesthesia were recruited for the study. Demographic data and oral health-related quality of life using the Early Childhood Oral Health Impact Scale (ECOHIS) were collected before the surgery. Postoperative complications and oral health-related quality of life were evaluated after 24 hours and at a one-week follow-up appointment. Results All 200 children returned for the follow-up appointment after one week. Pain was found to be the most common postoperative complication after 24 hours (52%) and one week (6%). The oral health-related quality of life showed a significant improvement after one week (P < 0.001) Conclusion Children may experience a postoperative complication after full-mouth rehabilitation, which resolves within a week. Dental pain was the most common operative complication in the present study. Oral health-related quality of life showed significant improvement after full-mouth rehabilitation.

Bite force evaluation at maximal intercuspal position: An in vivo comparative study between stainless steel and zirconia crowns on primary molar teeth

Objective

The objective of this study was to clinically evaluate and compare the mean bite force changes at maximum intercuspal position, along with parental satisfaction following full crown restoration using stainless steel crown/zirconia crown on primary molar teeth using digital occlusal analysis system T-Scan III (Tekscan Corp, Boston, Mass., USA).

Materials and Methods

Thirty-six primary molars of children aged 6-9 years with pulpal involvement were selected for the study. The selected teeth were allocated to either of the two groups using simple random sampling technique: Group A = stainless steel crowned teeth and Group B = zirconia crowned teeth. The mean bite force was recorded before the placement of the crown, after the placement of the crown, and after 1 month-follow-up. The inter-group and intra-group comparison was done among the groups. After the placement of the crown, parents were asked to fill out a questionnaire for assessing parental satisfaction.

Results

A significant result in the bite force on crowned tooth, vertical dimension was seen from baseline to 1-month follow-up between the SSC and zirconia groups. In the zirconia crown group, the mean bite force was more compared to the stainless steel crown group. Parents' satisfaction was higher with zirconia crown in terms of color and esthetics.

Conclusion

SSC is more acceptable than zirconia crown since occlusal re-equilibration was attained better in SSC as compared to zirconia crown.

Is the Metallic Color of Stainless Steel Crown Satisfying for Cooperative Children and their Parents? a Preliminary Study

STATEMENT OF THE PROBLEM

Currently, the demand for tooth-colored restorations in children and young adults is increasing. Stainless steel crown (SSC) is the most common restoration for decayed primary molars. Given the dark metallic color of SSC, the esthetic appearance of this restoration is poor and subsequently their acceptance is still a matter of debate.

PURPOSE

This study was conducted to evaluate the effect of restoration's color on children's daily living conditions and compare the clinical and radiographic success rates of composite resins with SSC in primary molars.

MATERIALS AND METHOD

This clinical trial study was performed on 70 primary molars in 44 healthy 4- to 7-year-old children. The children were randomly divided into two groups restored with SSC and restored with composite resin. Two researcher-made questionnaires were used to assess the children's satisfaction concerning the appearance and color of restoration. The data were analyzed with SPSS 20 using chi-squared, Fisher's, and Mann-Whitney U tests. The significance level was set at p< 0.05.

RESULTS

Children's satisfaction with restoration color in the treatment session was 75% in the SSC group and 85% in the composite resin group. However, the difference was not statistically significant (p= 0.246). After one year of follow-up, the satisfaction rate decreased to 69% in the SSC group and increased to 90.6% in the composite resin group, with a significant difference (p< 0.001). Moreover, the frequency of clinical success was 95% in the SSC group and 96.7% in the composite resin group, with no statistically significant difference (p= 0.749). The frequency of radiographic success was 87.5% in the SSC group and 100% in the composite resin group; this difference was not significant (p= 0.061).

CONCLUSION

The results verified that restoration color was not important for cooperative children in the treatment session. However, after one year, children who received composite resin restorations were pointedly more satisfied than those who were treated with SSC restorations.

Novel 3D Printed Resin Crowns for Primary Molars: In Vitro Study of Fracture Resistance, Biaxial Flexural Strength, and Dynamic Mechanical Analysis

This study evaluated the fracture resistance, biaxial flexural strength (BFS), and dynamic mechanical analysis (DMA) of three-dimensional (3D) printing resins for the esthetic restoration of primary molars. Two 3D printing resins, Graphy (GP) and NextDent (NXT), and a prefabricated zirconia crown, NuSmile (NS), were tested. GP and NXT samples were 3D printed using the workflow recommended by each manufacturer. Data were collected and statistically analyzed. As a result of the fracture resistance test of 0.7-mm-thick 3D printed resin crowns with a thickness similar to that of the NS crown, there was no statistically significant difference among GP (1491.6 ± 394.6 N), NXT (1634.4 ± 289.3 N), and NS (1622.8 ± 323.9 N). The BFS of GP was higher for all thicknesses than that of NXT. Both resins showed high survival probabilities (more than 90%) when subjected to 50 and 150 MPa. Through DMA, the glass transition temperatures of GP and NXT were above 120 °C and the rheological behavior of GP and NXT according to temperature and frequency were analyzed. In conclusion, GP and NXT showed optimum strength to withstand bite forces in children, and 3D printed resin crowns could be an acceptable option for fixed prostheses of primary teeth.

Parental and Child Outlook on the Impact of ECC on Oral Health-related Quality of Life: A Prospective Interventional Study

AIM

To evaluate the perspectives of parents and children on the impact of early childhood caries (ECC) on the oral health-related quality of life (OHQoF).

MATERIALS AND METHODS

About 400 children aged 3-5 years were recruited for the study. About 200 children who were caries-free were the controls for the study. The remaining 200 consisted of children who were diagnosed with ECC and required dental rehabilitation under general anesthesia. Oral health-related quality of life was recorded at baseline and 6 months after intervention using the Michigan oral health-related quality of life scale. Data were analyzed and evaluated using Statistical Package for Social Sciences (SPSS) Version 25.0.

RESULTS

Children with ECC were found to have a significantly lower oral health-related quality of life compared with caries-free children, and a statistically significant difference was seen between both groups. The main concern for both parents and children at baseline was pain at the first visit when the evaluation was done. After the intervention, a significant improvement in the oral health-related quality of life was seen.

CONCLUSION

Early childhood caries was found to have detrimental effects on the oral health-related quality of life. Full-mouth rehabilitation under general anesthesia was found to bring a significant improvement in the oral health-related quality of life. The perspectives of both parents and children were found to be similar.

CLINICAL SIGNIFICANCE

Early childhood caries has an impact on the lives of children and their parents. Oral health-related quality of life was low with children suffering from ECC. Full-mouth rehabilitation under general anesthesia can significantly improve the OHRQoL of children. Continuous monitoring of the children with regular follow-ups and parental education should be enforced to prevent the relapse of ECC.

Comparative evaluation of the fracture resistance of newly developed prefabricated fibreglass crowns and zirconium crowns

BACKGROUND

Prefabricated fibreglass crowns (PFCs) require less tooth structure reduction than prefabricated zirconium crowns (PZCs) for restoring primary molars. Little is known, however, about their mechanical properties.

AIM

To investigate the fatigue survival and fracture resistance of PZCs and PFCs cemented with two different types of luting cement [glass-ionomer cement (GIC) and resin-modified GIC (RMGIC)].

DESIGN

One hundred and twenty extracted human primary molars were randomly divided into subgroups (n = 15) according to the crown type (PFCs/PZCs), the luting cement (GIC/RMGIC) and crowns subjected to the chewing simulation test with thermocycling mechanical loading (CSTTML). The surfaces of the teeth were reduced by approximately 2 mm in the PZC group and 1 mm in the PFC group. All the samples were subjected to fracture tests.

RESULTS

None of the samples subjected to CSTTML exhibited signs of surface damage, fracture or premature debonding. The forces required to fracture PFCs were higher than those required for PZCs in all groups (p = .001). The highest mean fracture resistance values were obtained from the group of PFCs cemented with GIC that were subjected to the CSTTML (2515.8 N ± 619.2 N).

CONCLUSIONS

PFCs presented high fatigue survival and could be used as alternatives to PZCs as they require less tooth structure reduction. Crowns cemented with GIC had a similar fracture resistance value when compared with RMGIC.

Are zirconia crowns the superior choice when restoring primary posterior molars?

Data sources Electronic database searches were carried out using predefined search terms using Embase, Google Scholar, Medline, The Cochrane Library, The Cochrane Central Register of Controlled Trials and Latin American and Caribbean Health Sciences Literature. The Trip medical database was also used to identify randomised control trials investigating stainless steel and zirconia crowns. Studies published from 1 January 2000 until 6 June 2021 were included, and reference lists of included studies analysed to ensure data saturation along with grey literature searches.Study selection Inclusion criteria included research published in English only, randomised control trials investigating the clinical and radiographic effectiveness of zirconia crowns compared to stainless steel crowns, the rehabilitation of pulp-treated posterior primary teeth and randomised control trials with children in good health. Expert opinion, case reports and reviews were excluded. Studies with a follow-up period of less than 12 months, studies including children with special care requirements or non-compliant children were also excluded.Data extraction and synthesis Two reviewers (AKP, VKC) were involved with the primary search of abstracts and titles independently; both reviewers were involved in full text assessment. Disagreements were resolved by a third reviewer (NRV). The study characteristics, number of teeth evaluated, follow-up duration, type of zirconia and stainless steel crowns, outcome assessed and outcome results were extracted. Extracted data was analysed using Review Manager, Version 5.3 and dichotomous data was summarised as risk ratios with 95% confidence intervals. Continuous data was summarised as mean difference. Heterogeneity was summarised by I2 scores and a random-effects model and Mantel-Haenszel statistical test was used.Results From the initial 641 studies screened, six studies met the inclusion criteria for the systematic review and were included for analysis. Risk of bias assessment for the included studies was graded as 'low' for three of the six included studies and 'some concern' for the remaining three studies. This was based upon allocation concealment in the randomised control trials. Clinical failures were observed in 63 of 497 events. Rehabilitation with zirconia crowns may result in less clinical failures than stainless steel crowns: risk ratio 0.48; 95% CI (0.15-1.52) p = 0.021. Gingival health was better with zirconia rather than stainless steel crowns: risk ratio 0.32; 95% CI (-0.42-0.23) p <0.001.Conclusions Primary posterior teeth restored with zirconia crowns may have 52% less risk of experiencing clinical failures than teeth with stainless steel crowns and better gingival health than stainless steel crowns, observed after 12 months. However, due to the low quality of included studies and 'very low' grade rating of the evidence provided, further clinical trials are required to provide further evidence on the clinical and radiographic effectiveness of zirconia and stainless steel crowns.

In Vitro Study of Laser-Assisted Prefabricated Ceramic Crown Debonding as Compared to Traditional Rotary Instrument Removal

This study compared the laser and rotary removals of prefabricated zirconia crowns in primary anterior and permanent posterior teeth. Sixty-two extracted teeth were prepared for prefabricated zirconia crowns cemented with resin-modified glass-ionomer cement. Specimens underwent crown removals by a rotary handpiece, or erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser. Pulpal temperatures, removal times, and scanning electron microscopy (SEM) examinations were compared. The average crown removal time for rotary and laser methods was 80.9 ± 19.36 s and 353.3 ± 110.6 s, respectively, for anterior primary teeth; and 114.2 ± 32.1 s and 288.5 ± 76.1 s, respectively, for posterior teeth (p < 0.001). The maximum temperature for the rotary and laser groups was 22.2 ± 8.5 °C and 27.7 ± 1.6 °C for anterior teeth, respectively (p < 0.001); and 21.8 ± 0.77 °C and 25.8 ± 0.85 °C for the posterior teeth, respectively (p < 0.001). More open dentinal tubules appeared in the rotary than the laser group. The rotary handpiece removal method may be more efficient than the laser with lower pulpal temperature changes. However, the laser method does not create noticeable tooth or crown structural damage compared to the rotary method.

Is zirconium or stainless steel the most suitable crown material for less dentin stress in endodontically treated teeth?

BACKGROUND: Stainless steel crowns (SSCs), which have been used frequently in the treatment of first permanent molars in children until now, has become less applicable due to its poor aesthetic appearance. Zirconia crowns (ZCs) have become more popular due to their aesthetic advantage. However, stress transmission of ZCs to dental tissues under occlusal forces in endodontically treated teeth has not been described. OBJECTIVE: The aim of this study was to compare the stress distribution of different crown materials (ZCS, SSCs) and adhesive materials on dentin in endodontically treated permanent teeth and to specify the crown-adhesive model with lower stress. METHODS: Finite element analysis (FEA) was used to apply a force of 300 N from the inner part of the buccal tubercles (vertical loading) and a lingo-buccal at an angle of 30 degrees (oblique loading) of the first permanent molars (FPM) with different crown (ZCS, SSCs) and adhesive (Glass ionomer cement, Resin modified glass ionomer cement, Resin cement) materials in twelve separate models. The von Mises values obtained from the models were compared and the optimal stress values were determined by FEA. RESULTS: The lowest stress values of dentin were found in zirconia crown model with glass ionomer cement (GIC) adhesive under vertical loading (26,793 Mpa). In the zircon crown and GIC adhesive model, less von Mises stress occurred on the dentin under all conditions. CONCLUSIONS: ZCs and GIC adhesive may be recommended for teeth with a high probability of dentin fracture.

Zirconia Crowns for Primary Teeth: A Systematic Review and Meta-Analyses

Objective: The aim of this systematic review was to summarize the literature regarding the clinical performance of zirconia crowns for primary teeth. Materials and Methods: Four electronic databases, Ovid, PubMed, Scopus, and Web of Science were searched. Clinical, observational, and laboratory studies were included. Studies that assessed the performance of zirconia crowns for primary teeth using outcomes such as gingival and periodontal health, parental satisfaction, color stability, crown retention, contour, fracture resistance, marginal integrity, surface roughness, and recurrent caries were included. Risk of bias was assessed using different assessment tools depending on the type of the assessed study. Results: Out of the 2400 retrieved records, 73 full-text records were assessed for eligibility. Thirty-six studies were included for qualitative analysis. The included studies reported that zirconia crowns for primary teeth were associated with better gingival and periodontal health, good retention, high fracture resistance, color stability, high parental acceptance, good marginal adaptation, smooth cosmetic surface, and no recurrent caries. Conclusion: Zirconia crowns are promising alternative to other restorative materials and crowns in the field of pediatric dentistry. They showed higher properties and performance in different clinical aspects and great parental satisfaction.

Evaluation of the Clinical Performance of NuSmile Pedodontics Zirconia Crowns in Pulp-Treated Primary Teeth-2 Years Follow-Up Study

OBJECTIVES

 There is a lack of information regarding the longevity of prefabricated crowns on primary teeth. Therefore, the objective of the present study was to evaluate the clinical success rate of NuSmile pediatric Zirconia crowns in both primary anterior and posterior teeth up to 2 years in terms of gingival health, levels of plaque, restoration failure, and marginal integrity.

MATERIALS AND METHODS

 This interventional study evaluated the clinical performance of NuSmile primary Zirconia crowns on 232 (172 primary incisors and 60 primary molars) pulp-treated primary teeth. Statistical analysis included independent t-test and Kaplan-Meier survival method for which the level of significance was set up at p < 0.05.

RESULTS

 Gingival and plaque index of the teeth restored with NuSmile Zirconia crowns (test tooth) compared with adjacent and antagonist teeth (control tooth) showed no statistically significant difference at all time intervals (p > 0.05). The Kaplan-Meier survival graph indicated that only 34% of NuSmile Zirconia incisor crowns and 86% of NuSmile Zirconia molar crowns have survived at the end of 24 months. Of the 172 NuSmile Zirconia incisor crowns placed, only 82 teeth survived at the end of 2 years and the majority of the crowns completely lost the Zirconia crown. The Kaplan-Meier graph also indicated that more than two-thirds of crowns, i.e., 90% incisor crowns and 76% of molar crowns, had good marginal integrity at the end of 24 months.

CONCLUSIONS

 Zirconia pediatric crowns preserve and maintain gingival health and have long-term survival rates with good retention and marginal integrity, indirectly preventing secondary caries. Hence, Zirconia pediatric crowns are a well-suited restoration of choice for primary teeth rehabilitation.

Evaluation of the Clinical, Child, and Parental Satisfaction with Zirconia Crowns in Maxillary Primary Incisors: A Systematic Review

Background

With the increasing demand for aesthetics in children and their parents, the treatment of decayed primary anterior teeth is one of the biggest challenges in pediatric dentistry. Zirconia crowns have provided a treatment alternative to address the aesthetic concerns and ease of placement of extracoronal restorations on primary anterior teeth.

Methods

The electronic databases including PubMed, Scopus, Google Scholar, and Embase were searched on articles published between January 2010 and January 2021. Studies relating to evaluating the clinical success and satisfaction of both parents and children about zirconia crowns in maxillary primary incisors were reviewed.

Results

Nine studies met the criteria for final inclusion. Findings from these studies showed that parental and child satisfaction with zirconia crowns is high with clinically acceptable restorations in the maxillary primary incisors.

Conclusion

Parental and child satisfaction with zirconia crowns is high with clinically acceptable restorations in the maxillary primary incisors. In addition, larger sample sizes and longer follow-ups are required in future studies.

Factors Influencing the Survival of Preformed Zirconia Crowns in Children Treated under General Anesthesia

Aim

This study aimed to retrospectively evaluate the success of zirconia crowns placed in the anterior teeth of children and evaluate the impact of pulp therapy of the tooth on the rate of failure.

Materials and Methods

A total of 70 anterior teeth of 20 children aged between 3 and 5 years who had undergone the placement of zirconia crowns under general anesthesia were followed up for 24 months. Kaplan-Meier Survival curves were plotted for the estimation of two-year survival time. The outcomes for teeth that had received pulp therapy were compared to those that had not received pulp therapy.

Results

Kaplan-Meier survival analysis of 70 crowns observed over a two-year period showed that mean survival time for the crowns was 38.7 months with a confidence interval ranging from 38.1 months to 39.3 months. When the survival of the crowns was observed based on the presence or absence of symptoms, it was observed that only 4 out of the 70 crowns were symptomatic (with or without crown loss) at the end of two years, giving a success rate of 94.3%. The mean survival time was also increased to 39.5 months (confidence interval 39.15-39.98 months).

Conclusion

Zirconia crowns provide an acceptable level of success and longevity. Crowns placed on teeth after pulp therapy are more likely to fail than those placed on teeth without pulp therapy.