الفهرس 
Materials and methodsOnly 14 pages are availabe for public view
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Abstract
The present study was conducted to evaluate three intra-canal post types used in restoration of mutilated primary anterior teeth affected by ECC; composite posts, orthodontic omega wire posts, and glass fiber posts.
The in vitro study was conducted on 92 extracted primary upper incisors. Four groups were created in which composite posts, omega wire, and glass fiber posts were cemented in the canal with flowable composite; and glass fiber posts in the fourth group were cemented with self-adhesive dual cure resin cement. In each group, 13 specimens were subjected to tensile test to measure the tensile bond strength, and 10 specimens were subjected to fracture test.
The in vivo study was conducted on 35 grossly carious primary upper incisors in 10 healthy children of mean age 4.2 years old. selected teeth were restored with composite posts and glass fiber posts, and composite crowns were built up by aid of strip crowns. The patients were checked every 6 months for a period of one year and grading of both marginal adaptation and secondary caries were done in each recall visit.
The following results were found from in vitro study:
Glass fiber posts when cemented with self-adhesive resin cement showed the highest tensile bond strength followed by orthodontic omega wire posts, composite posts, and the lowest strength was recorded with glass fiber posts when cemented with flowable composite. However, no statistically significant difference was observed between the groups (P>0.05).
In tensile test, most of failures (69%) recorded in glass fiber posts when cemented with composite were adhesive failures, on the other hand, the
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same fiber posts when cemented with self-adhesive resin cement showed no adhesive failure at all. The other two posts, composite and omega wire, showed core failures more than adhesive (77% and 69% respectively).
The strength needed to cause failure for the post itself was significantly higher (P=0.008) than the one needed to cause core or adhesive failures in tension test.
In fracture test; orthodontic omega wire posts showed the highest fracture resistance followed by glass fiber posts when cemented with self-adhesive resin cement and composite posts, both had shown almost the same strength values. The lowest fracture resistance was recorded with glass fiber posts when cemented with flowable composite. Again, no statistically significant difference was observed between the groups.
In both tensile and fracture tests; the glass fiber posts cemented with flowable composite had showed the lowest retention and fracture strength, and was the weakest restoration modality among the four groups. However, when these fiber posts were cemented with self-adhesive, dual cure resin cement, it showed superior strength values in both tensile and fracture tests.
Following results were found from in vivo study:
1. Glass fiber posts showed high retention rate (96%) demonstrated in teeth present at 6 months, and (88%) retention in those present after one year.
2. On the other hand, restorations supported by composite posts showed lower success rate than glass fiber posts. Only 79% of the teeth evaluated at 6 month showed success; this rate decreased to 73% after one year.
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3. Failures shown in glass fiber post restorations were favorable, i.e. adhesive, so, only re-cementation of the post/core assembly with self-adhesive resin cement would repair it with a simple noninvasive technique.
4. Failures in both restoration techniques were mostly due to trauma. Secondary caries was not reported in any restoration after one year follow-up.