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Azerbaycan Saytlari

 »  Home  »  Endodontic Articles 3  »  The long-term sealing ability of an epoxy resin root canal sealer used with five gutta percha obturation techniques
The long-term sealing ability of an epoxy resin root canal sealer used with five gutta percha obturation techniques
Discussion - References.



Discussion.
In order to evaluate the sealing ability of root fillings, several in vitro methods have been designed. It is important to appreciate that not only is the apical seal of the root canal of importance, but the coronal seal is of equal importance for the success of treatment (Saunders & Saunders 1994a). The most common method used to assess leakage remains the measurement of dye penetration (Wu & Wesselink 1993). The results of dye penetration studies, however, are confusing and often result in variable conclusions (Wu & Wesselink 1993, Dalat & Spångberg 1994). This lack of agreement has been discussed by Wu & Wesselink (1993), who questioned the validity of leakage studies and recommended that more research should be devoted to leakage study methodology. The nature and the amount of leakage observed with this technique cannot be extrapolated to an in vivo situation. On the other hand, laboratory testing remains the only valuable preclinical screening test that can predict or indicate clinical performance (De Moor & Martens 1999).
Longitudinal sectioning of roots and the linear measurement of dye penetration were used in the present study for the measurement of leakage. On the one hand, it is clear that this experimental model cannot mimic the in vivo situation. On the other hand, it enables the observation of dye penetration and whether or not that is associated with porosities in the gutta-percha, the presence of empty spaces, stripping of the gutta-percha from the solid core system or changes in the structure of thermoplasticized gutta-percha. Splitting the root longitudinally combined with dye penetration also enables the demonstration of the pattern of dye penetration.
One of the aims of the present investigation was to verify the findings of a previous study (De Moor & De Boever 2000). In the present study and in our previous fourmonth study (De Moor & De Boever 2000) obturation with Soft-Core obturators resulted in greater leakage scores with higher standard deviations when compared with the other filling techniques. This may indicate that Soft-Core obturators are ineffective in the apical obturation of well-instrumented straight root canals under ideal conditions. In addition, it was also seen that apical leakage increased with time up to 4 months in all five obturation techniques. These findings were in general agreement with those of others (Gurney et al . 1971), in which leakage increased during the five-month evaluation period. Other studies on long-term apical sealing ability as a function of time and of the filling techniques investigated in the present study do not appear to have been published.

Table 3. Group means, standard deviations, and minimum and maximum extent of apical dye penetration in mm.

apical dye penetration
 
Table 4. Group means, standard deviations, and minimum and maximum extent of coronal dye penetration in mm.

coronal dye penetration

The results regarding coronal leakage revealed no statistically significant differences between the three non-carrier systems and between the two carrier systems. This lack of a significant effect was not surprising, given that a similar procedure was used to seal the orifices of the specimens.
In our previous study (De Moor & De Boever 2000) it was found that the preheated gutta-percha of the Soft- Cores appeared to be porous when viewed under the microscope. Despite previously reported data in favour of the use of AH26 in combination with the gutta-percha coated system Thermafil (Dalat & Spångberg 1994), the presence of porosities in the gutta-percha of the Soft-Core obturators might explain the greater amounts of apical leakage found in the present and in our previous studies (De Moor & Martens 1999, De Moor & De Boever 2000). These porosities did not appear to be of importance when scoring the amount of coronal dye leakage.

References.

Dalat DM, Sp?ngberg LSW (1994) Comparison of apical leakage   in root canals obturated with various gutta-percha techniques using a dye vacuum   tracing method. Journal of Endodontics 20 , 315-9.
  De Moor RJG, De Boever JG (2000) The sealing ability of an epoxy resin root   canal sealer used with five gutta-percha obturation techniques. Endodontics   and Dental Traumatology 16 , 291-7.
  De Moor RJG, Martens LC (1999) Apical microleakage after lateral condensation,   hybrid gutta-percha condensation and Soft-Core obturation: an in vitro evaluation.   Endodontics and Dental Traumatology 15 , 239-43.
Endotec Thermal Endodontic Condenser System (1986) The Warm Lateral Condensation   Technique Clinical Manual . Dentsply Int. Inc. Milford DE, USA: The LD Caulk   Division.
  Gurney BF, Best EJ, Gervasio G (1971) Physical measurements on gutta-percha.   Oral Surgery, Oral Pathology and Oral Medicine 32 , 260-70.
  Gutmann JL, Saunders WP, Saunders EM, Nguyen L (1993) An assessment of the   plastic Thermafil obturation technique. Part 2. Material adaptation and sealability.   International Endodontic Journal 26 , 179-83.
  Hovland EJ, Dumsha TC (1985) Leakage evaluation in vitro of the root canal   sealer cement Sealapex. International Endodontic Journal 18 , 179-82.
  Johnson WB (1978) A new gutta-percha technique. Journal of Endodontics 4 , 184-8.  
  Kennedy WA, Walker WA, Gough RW (1986) Smear layer removal effects on apical   leakage. Journal of Endodontics 12 , 21-7.
  Kontakiotis EG, Wu M-K, Wesselink PR (1997) Effect of sealer thickness on   long-term sealing ability: a 2 year follow-up study. International Endodontic   Journal 30 , 307-12.
  Saunders WP, Saunders EM (1994a) Coronal leakage as a cause of failure in   root canal therapy: a review. Endodontics and Dental Traumatology 10 , 15-8.  
  Saunders WP, Saunders EM (1994b) Influence of the smear layer on the coronal   leakage of Thermafil and laterally condensed gutta-percha root fillings with   glass ionomer sealer. Journal of Endodontics 20 , 155-8.
  Schilder H (1967) Filling root canals in three dimensions. Dental Clinics   of North America 11 , 723-44.
  Tagger M, Tamse D, Katz A, Korzen BH (1984) Evaluation of the apical seal   produced by a hybrid root canal filling method, combining lateral condensation   and thermatic compaction. Journal of Endodontics 10 , 299-303.
  Taylor JK, Jeansonne BG, Lemon RR (1997) Coronal leakage: effects of smear   layer, obturation technique, and sealer. Journal of Endodontics 23 , 508-12.  
  Wu M-K, Wesselink PR, Boersma J (1995) A 1-year follow-up study on leakage   of four root canal sealers at different thicknesses. International Endodontic   Journal 28 , 185-9.
  Wu MK, Wesselink PR (1993) Endodontic leakage studies reconsidered. Part   I: Methodology, application and relevance. International Endodontic Journal   26 , 37-43.
  Yee FS, Marlin J, Krakow AA, Grin P (1977) Three-dimensional obturation of   the root canal injection molded, thermoplasticized dental gutta-percha.   Journal of Endodontics 3 , 168-74.