Tooth Discoloration Using Calcium Silicate-Based Cements For Simulated Revascularization in Vitro

Abstract

The endodontic revascularization may be an alternative treatment for necrotic immature teeth, however, several treatment steps may cause tooth discoloration. This study evaluated the use of three calcium silicate-based cements with different radiopacifying agents on the color alteration (∆E) of extracted premolars after simulation of revascularization. Forty single rooted extracted premolars were shaped with #1-6 gates Glidden drills, rinsed with sodium hypochlorite, and filled with fresh human blood. Three calcium silicate-based cements with different radiopacifying agents (bismuth oxide - CSBi, calcium tungstate - CSW, and zirconium oxide - CSZr) were applied over the blood clot (n=10). The control group received the application of a temporary zinc oxide-based cement (TFZn) (n=10). ∆E was measured with a spectrophotometer, using the L*a*b* color system of the International Commission on Illumination (CIELab), in different times: prior to the preparation of the access cavity (t0); right after treatment (t1); and after one (t2), two (t3), three (t4) and four (t5) months. The tooth site for color evaluation was standardized by silicon matrix, the color reading was performed 3 times per tooth, and the teeth were stored in 37º water between evaluations. ∆E, whiteness (WID index) and yellowness (b*) were evaluated. Data were subjected to one-way ANOVA and repeated measures ANOVA, followed by Tukey’s post hoc test (α=0.05). All groups were similar in ∆E1 (t0-t1). The ∆E was the lowest and constant in the control group. In all evaluation times, CSBi presented the highest ∆E (p<0.01). CSW and CSZr were similar in all evaluated times and presented intermediate ∆E values. WID index from CSBi and CSW presented more distancing from ‘white’ reference. CSBi presented the greatest decrease in yellowness (b* value). The cement containing bismuth oxide presented the highest color alteration values. All tested calcium silicate-based cements presented clinically perceptible discoloration. Calcium tungstate and zirconium oxide may be used as alternative radiopacifiers to decrease tooth discoloration after endodontic tooth revascularization.

The effect of different calcium silicate-based pulp capping materials on tooth discoloration: an in vitro study

“…In another study using bovine teeth, Marciano et al [ 5 ] found that teeth filled with Portland cement that have different radiopacifiers other than bismuth oxide (zirconium oxide and calcium tungstate) have exhibited color stability, and no color change have occurred after zirconium oxide and calcium tungstate were placed in contact with collagen, but, discoloration was observed when the authors placed bismuth oxide in contact with the collagen [ 31 ]. Similar findings have been reported more recently demonstrating again that, calcium silicate cement containing bismuth oxide was found to cause the highest color change compared to those with zirconium oxide or calcium tungstate as radiopacifiers when the cements were placed into extracted human premolars in contact with blood [ 32 ].…”

Discoloration Potential of Biodentine: A Systematic Review

“…The most common method for color change evaluation was spectrophotometry, used in six studies [12,13,21,27,41,42], followed by spectrophotometry used with a digital camera [14,24,25,28,40], colorimetry [22], spectroradiometry [23], and only a digital camera [26].…”

“…Color changes were measured by calculating ∆E values in all studies. Eleven publications [12][13][14]21,22,[24][25][26]28,40,42] indicated human eye perceptible color change ranging from ∆E1.2 to ∆E3.7, whereas three articles [23,27,41] did not provide numeric information about ∆E thresholds, which were taken as perceptible to the human eye.…”

“…The first commercial CSC introduced to the market, grey MTA, was composed of calcium, silica, and bismuth oxide [6]. Many studies reported that grey MTA leads to tooth discoloration [2,[9][10][11][12][13][14][15]. To overcome this limitation, white MTA (wMTA) has been developed with a reduction of aluminum, magnesium, and ferrous oxides.…”

Spectrophotometric analysis of internal bleaching of traumatized teeth with coronal discoloration following regenerative endodontic procedures

“…Another factor related to coronary discoloration following REP is the use of calcium silicate-based cervical barriers 1,7,9,10,[12][13][14][15] and their interaction with the blood clot 16 , especially those that have bismuth oxide in their composition, which when in contact with collagen matrix result in a darkened precipitate 13 .…”