Pengaruh penambahan tepung ubi kayu pada bahan cetak alginat terhadap setting time dan recovery from deformation

ARYATHI, Luh Gde Rai, Dr.drg. Siti Sunarintyas, M.Kes

2005 | Tesis | S2 Ilmu Kedokteran Gigi

Sulitnya memperoleh bahan cetak di beberapa daerah terpencil menjadikan dokter gigi melakukan modifikasi bahan cetak alginat dengan penambahan tepung ubi kayu. Bahan cetak harus memiliki setting time yang cukup sehingga operator dan pasien dapat melakukan pencetakan gigi dengan baik. Bahan cetak juga harus memiliki recovery from deformation saat dilepas dari mulut sehingga dapat mencetak daerah undercut tanpa berubah bentuk. Hal tersebut menentukan dalam keakurasian reproduksi cetakan. Penelitian ini bertujuan untuk mengetahui pengaruh rasio penambahan tepung ubi kayu pada bahan cetak alginat terhadap setting time dan recovery from deformation. Tiga puluh lima spesimen dibagi menjadi 5 kelompok: kelompok A sebagai kontrol, kelompok B, C, D dan E diberi penambahan tepung ubi kayu masing-masing 12,5%, 25%, 50%, 75%. Pengukuran setting time menggunakan alat ukur indikator setting time berbentuk batang silindris dari bahan poly(methyl methacrylate) sedangkan untuk recovery from deformation menggunakan alat uji deformasi yang memiliki keakuratan 0,01 mm. Uji anava menunjukkan adanya perbedaan yang bermakna (p<0,05) pada penambahan tepung ubi kayu ke dalam bahan cetak alginat terhadap setting time dan recovery from deformation namun pada recovery from deformation antara kelompok kontrol dan kelompok penambahan tepung ubi kayu 12,5% menunjukkan perbedaan yang tidak bermakna (p>0,05). Penambahan tepung ubi kayu 75% tidak dapat dilakukan pengukuran recovery from deformation karena bahan cetak tidak mengalami gelasi. Kesimpulan dari penelitian ini adalah bahwa penambahan tepung ubi kayu sampai dengan 75% masih memenuhi standar setting time ANSI/ADA dan penambahan tepung ubi kayu sampai dengan 50% masih memenuhi standar recovery from deformation ANSI/ADA.

The difficulty of getting impression material in several isolated regions makes dentist modify an impression material of alginate by adding cassava starch. The impression material ought to have a sufficient setting time, so that the operator and the patient can compatibly produce the mouth impression. The impression material ought to have recovery form deformation when it is released form the mouth with the aim of being able to mould the undercut area without altering its structure. The aim of this study is to identify the influence of additional ratio of cassava starch on the impression material of alginate toward setting time and recovery from deformation. Thirty five specimens of impression material of alginate are grouped into five groups. Group A plays a role as a control; the groups B, C, D and E are given additional cassava starch as much as 12.5%, 25%, 50%, 75% subsequently. Measurement test of setting time employs an indicator of setting time which is in shape like cylinder bar and made of poly (methyl methacrylate). Meanwhile for recovery from deformation, it employs deformation equipment with the accuracy of 0.01 mm. The anova indicates that there is a significant difference on the addition of cassava starch into the impression material of alginate toward setting time and recovery from deformation (p<0.05). The LSD indicates for setting time that there is a significant difference on the all experiment groups (p<0.05). The LSD indicates for recovery from deformation, that is between the control group and the additional group of 12.5% of cassava starch indicates that there is no significant difference (p>0.05) and the another groups indicates that there is a significant difference except that cassava starch added as much as 75% can not be measured This study concludes that cassava starch added as much as 50% have fulfilled the standard ANSI/ADA for setting time and recovery from deformation.

Kata Kunci : Gigi,Bahan Cetak Alginat,Tepung Ubi Kayu,Setting Time,Recovery From Deformation