Cleidocranial dysplasia: a case report illustrating diagnostic clinical and radiological findings

Cleidocranial dysplasia (CCD) is a rare congenital defect, primarily affecting bones, undergoing intramembranous ossification. CCD presents with skeletal defects of several bones, the most striking feature of which are partial or complete absence of clavicles, late fontanels closure, and presence of open skull sutures and multiple wormian bones. These patients may be first noticed by the dentist because of the aesthetic problems or delayed eruption of teeth experienced by the patient. Here, we report a typical case of CCD in a 15-year-old female who had classical diagnostic feature of this syndrome.

A Comparative Evaluation of the Effect of Resin based Sealers on Retention of Crown Cemented with Three Types of Cement - An In Vitro Study

AIM

In an effort to control postoperative sensitivity, dentin sealers are being applied following crown preparations, with little knowledge of how crown retention might be affected. A previous study demonstrated no adverse effect when using a gluteraldehyde-based sealer, and existing studies have shown conflicting results for resin-based products. This study determined the retention of the casting cemented with three types of cement, with and without use of resin sealers and it determined the mode of failure.

MATERIALS AND METHODS

Extracted human molars (n=60) were prepared with a flat occlusal, 20-degree taper, and 4-mm axial length. The axial surface area of each preparation was determined and specimens were distributed equally among groups (n=10). A single-bottle adhesive system (one step single bottle adhesive system) was used to seal dentin, following tooth preparation. Sealers were not used on the control specimens. The test castings were prepared by using Ni-Cr alloy for each specimen and they were cemented with a seating force of 20 Kg by using either Zinc Phosphate (Harvard Cement), Glass Ionomer (GC luting and lining cement,GC America Inc.) and modified-resin cement (RelyXTMLuting2). Specimens were thermocycled for one month and were then removed along the path of insertion by using a Universal Testing Machine at 0.5 mm/min. A single-factor ANOVA was used with a p value of .05. The nature of failure was recorded and the data was analyzed by using Chi-square test.

RESULTS

Mean dislodgement stress for Zinc phosphate (Group A) was 24.55±1.0 KgF and that for zinc phosphate with sealer (Group D) was 14.65±0.8 KgF. For glass ionomer (Group B) without sealer, the mean value was 32.0±1.0 KgF and mean value for glass ionomer with sealer (Group E) was 37.90±1.0 KgF. The mean value for modified resin cement (Group C) was 44.3±1.0KgF and that for modified resins with sealer (Group F) was 57.2±1.2 KgF. The tooth failed before casting dislodgement in 8 to 10 specimens cemented with modified-resin cement.

CONCLUSION

Resin sealer decreased casting retentive stress by 46% when it was used with Zinc phosphate. However, sealer use resulted in 60% increased retention when it was used with Glass ionomer cement. The modified-resin cement produced the highest mean dislodgement stress, which nearly always exceeded the strength of the tooth.

Cut off values of laser fluorescence for different storage methods at different time intervals in comparison to frozen condition: A 1 year in vitro study

Aims:

The aim of the following study is to evaluate the change in laser fluorescence (LF) values for extracted teeth stored in different solutions over 1 year period, to give cut-off values for different storage media at different time intervals to get them at par with the in vivo conditions and to see which medium gives best results with the least change in LF values and while enhancing the validity of DIAGNOdent in research.

Materials and Methods:

Ninety extracted teeth selected, from a pool of frozen teeth, were divided into nine groups of 10 each. Specimens in Groups 1-8 were stored in 1% chloramine, 10% formalin, 10% buffered formalin, 0.02% thymol, 0.12% chlorhexidine, 3% sodium hypochlorite, a commercially available saliva substitute-Wet Mouth (ICPA Pharmaceuticals) and normal saline respectively at 4°C. The last group was stored under frozen condition at −20°C without contact with any storage solution. DIAGNOdent was used to measure the change the LF values at day 30, 45, 60, 160 and 365.

Statistical Analysis Used:

The mean change in LF values in different storage mediums at different time intervals were compared using two-way ANOVA.

Results:

At the end of 1 year, significant decrease in fluorescence (P < 0.05) was observed in Groups 1-8. Maximum drop in LF values occurred between day 1 and 30. Group 9 (frozen specimens) did not significantly change their fluorescence response.

Conclusions:

An inevitable change in LF takes place due to various storage media commonly used in dental research at different time intervals. The values obtained from our study can remove the bias caused by the storage media and the values of LF thus obtained can hence be conveniently extrapolated to the in vivo condition.