A comparative study of conventional and Hall techniques of crown placement using finite element stress analysis

BACKGROUND

Hall technique of crown placement causes the changes in vertical occlusal dimension; the mode of settlement of which needs to be explored.

AIM

To assess and compare the changing patterns of stress distribution following placement of stainless steel crowns on primary teeth by Hall and conventional techniques using a finite element model analysis.

MATERIALS AND METHODS

The clinical crown heights of primary molars restored with Hall and conventional techniques and opposing teeth in contact, vertical dimension changes in the primary canine area were measured using intraoral digital scan. T-scan was used to measure the changes in bite force while the finite element analysis was used to assess deformative changes on the 2^nd, 5^th, 10^th, and 15^th days.

RESULTS

The Hall technique of crown placement caused more stress distribution in the tooth supporting tissues that settled in 2 weeks as compared with conventional technique of crown placement in which settlement occurred in 2 days.

CONCLUSION

The settling of vertical occlusal dimension as well as stress distribution in Hall technique probably takes place by intrusion of crowned tooth and opposing teeth in contact.

A clinical and radiographic comparative evaluation of custom-made zirconia crowns using CAD-CAM and stainless steel crowns in primary molars

BACKGROUND AND AIM OF STUDY

Early childhood caries is a multifactorial disease process affecting children below 71 months of age and continues to be a global health problem. Stainless steel crowns (SSCs) are widely used and are very popular in pediatric dentistry due to its superiority and durability when compared with multisurface amalgam restorations. However, one of the major disadvantages with these crowns is the poor esthetics. Parents often request for a more esthetic alternative to the SSC. Zirconia crowns are one of the tooth-colored full crown restorations currently available for use in primary teeth. These are available as both preformed and custom-made crowns and show excellent esthetics. However, these require extensive tooth preparation with a subgingival finish lines, which would cause gingival trauma and bleeding during the preparation. The present study uses intraoral scanners for making the custom-made zirconia crowns, which will avoid the conventional impressions. Currently, there are no studies available in pediatric dentistry regarding CAD-CAM crowns. Hence, there is a need for the study.

AIM

The aim of this study is to clinically evaluate the performance of preformed SSCs and custom-made zirconia crowns in primary molars. To elicit parental and patient satisfaction with respect to preformed SSCs and custom made zirconia crowns and to radiographically compare the interproximal bone height for 1 year.

METHODS

The patients were selected with purposive sampling. The tooth of interest was prepared according to the crown it would receive. The upper and the lower arch of the tooth receiving custom-made zirconia crown was scanned using an intraoral scanner. The crowns were cemented using Type 1 glass ionomer cement (GIC) (SSC) and resin modified GIC (custom-made zirconia crown). After the crown placement, the patient and the parent's satisfaction was scaled regarding the time taken, comfort, cost of crown, appearance of crown, etc., using a 5-point Likert scale. A baseline radiograph was taken after crown placement. The patient was recalled every 3 months till 1 year for evaluation (loss of retention, loss of proximal contact, gingival inflammation, opposing tooth wear, and marginal integrity). At the end of 1 year, radiographs were taken to check the interproximal bone.

RESULTS

After 1 year evaluation of custom-made zirconia crowns and preformed SSCs in primary molars, it was shown that both SSC and zirconia crowns showed good gingival scores but zirconia crown was better than SSC in improving the gingival health. SSCs showed better results with respect to the opposing tooth wear and marginal adaptability. Parents as well as patients preferred a tooth-colored crown as a treatment option.

CONCLUSION

Custom-made zirconia crowns are comparable to the preformed SSCs and they show better gingival scores and excellent color match.

Assessment of the effect of probiotic curd consumption on salivary pH and streptococcus mutans counts

BACKGROUND

Antimicrobial methods of controlling dental caries that include probiotic agents can play a valuable role in establishing caries control in children at moderate to high risk for developing dental caries. Several studies have demonstrated the beneficial effects of use of various Probiotic products including curd. The objective of this study was to compare the effect of short-term consumption of probiotic curd containing Lactobacillus acidophilus and normal curd on salivary Streptococcus Mutans counts, as well as salivary pH.

MATERIALS AND METHODS

Forty, caries-free, 10-12 years old children were selected and randomly allocated to two groups. Test Group consisted of 20 children who consumed 200ml of probiotic curd daily for 30 days. Control Group consisted of 20 children who were given 200ml of regular curd for 30 days. Salivary pH and salivary Streptococcus Mutans counts were recorded at baseline and after 30 days and statistically compared using the Student's t-test.

RESULTS

Consumption of probiotic curd resulted in a statistically significant reduction in S. Mutans colony counts (P<0.001) as compared to regular curd. However, there was a slight reduction in pH (P>0.05) in both the groups.

CONCLUSION

Short-term consumption of probiotic curds can reduce oral S. Mutans counts. However, this caused a slight reduction in salivary pH.

Versatility of Dieffenbach's Modification of Weber Fergusson's Approach for Treatment of Maxillary Pathologies

OBJECTIVE

The aim of the study is to evaluate the usage of Dieffenbach's modification of Weber-Fergusons approach in the treatment of lesions involving maxilla.

STUDY

In this study five different maxillary pathologies were approached through Dieffenbach's modification of Weber-Fergusons approach. Partial and subtotal procedures were performed depending on the type of pathology and the extent of the lesion which was assessed both clinically and radiologically. The study evaluates the easy exposure of the site, post operative complications like scar formation and infra orbital nerve parasthesia.

RESULTS

There were two subtotal maxillectomy procedures and three partial maxillectomy procedures approached through Dieffenbach's modification of Weber-Fergusson's approach. All the cases recovered well in the post operative healing period without noticeable scarring. There was parasthesia in three cases which subsided in 3 months.

CONCLUSION

The approach through Dieffenbach's modification of Weber-Fergusons incision gave better visibility and accessibility to the lesions of maxilla. Because there is direct access to the pathology, the inadvertent resection of the un-involved structures is prevented thus minimizing the morbidity.

Oligodontia in the primary dentition: report of a case

Congenital absence of primary teeth is relatively rare. The prevalence, possible etiological factors and management of oligodontia was briefly reviewed. This paper reports a rare case of multiple missing (n=18) primary teeth in a 4-year-old male of Asian origin.

Continuous glucose monitoring system--useful but expensive tool in management of diabetes

Until recently, self monitoring of blood glucose (SMBG) was the only tool used for monitoring blood glucose levels. The limitation of SMBG is that it cannot continuously monitor blood glucose levels. In this paper, we present our initial experience with the continuous glucose monitoring system (CGMS) in three different clinical situations. With reduction in cost and further refinement in technology, CGMS could become a valuable tool for clinical practice and research studies in diabetes.