To study the relationship between effectiveness of bleaching of a particular technique and various factors influencing bleaching case selection.
- 68 pts with 80 internally bleached teeth recalled 1-5yrs; records obtained
- recorded kodachrome color records of each tooth and color changes noted
- if teeth re-discolored to pre-op shade or failed to respond to bleaching, was considered a failure
- teeth were bleached via: pumiced crowns, RD, GP removed 2-3mm from CEJ, crown dessicated with EtOH,cp soaked 30% H202 w/ heat source 5min intervals for 20min, ZOE to CEJ with bleach soaked CP for 48 hrs, tx repeated until proper shade achieved, then restored
- 25% of bleached teeth subsequently failed esthetically
- 17.5% failed to respond to tx, 7.5% re-discolored
- of successes, 28.7% were complete successes and 48.3% retained improved esthetics
- no relationship between pts age and bleaching success
- if etiology of stain is internal, success was high: 87.8% (carious exposure) to 95.3% (trauma, necrosis)
- discoloration due to medicaments/restorations cannot be bleached successfully
- shorter discoloration time, see increased bleaching success: <1yr 87.5% success, 1-5yr 71%, >5yr 66.6%
- gradual discoloration success? 82.3%. Rapid? 50%
Internal bleaching has high success, especially if stain etiology is internal and shade discolored less time and more gradually.