A 21-year-old female patient reported to the Department of Conservative Dentistry and Endodontics with the complaint of discoloration in upper front teeth []. History of the patient revealed the presence of yellowish brown and white patches on teeth since childhood. Clinical examination showed the presence of dark yellow patches in maxillary central incisors and white patches on the facial surface of all teeth. Careful exploration of teeth revealed intact and smooth enamel surfaces. Several treatment options suggested to the patient were microabrasion, microabrasion along with bleaching, and direct or indirect veneers. Patient declined any procedure that included preparation of her intact tooth surfaces. After discussion, it was agreed to use enamel microabrasion followed by bleaching to improve the appearance of her teeth. The maxillary canines and incisors to be treated were first cleaned with pumice and water slurry. Petroleum jelly was applied around the cervical portion of the teeth to prevent leakage of the hydrochloric acid or damage to the gingiva. The teeth were then isolated using rubber dam. Freshly prepared solution of 11% hydrochloric acid was applied using cotton pellet on the discolored area followed by application of coarse composite contouring discs (Super Snap, Shofu Inc., Japan) at low speed for 10 seconds per tooth []. Same procedure was repeated 3 times at the same visit, which resulted in lightening of the dark areas to a great extent []. White spots were still evident on the labial surfaces of teeth. Thereafter, the remaining acid was rinsed from the teeth by use of gentle air water pressure and a high-volume aspirator. All teeth were finished using fine and extra fine grit abrasive discs (Super Snap). After finishing, the bleaching agent (XX-White™, DENT’N Co., France) was applied over the labial surfaces of isolated teeth, followed by light activation using a bleaching light (Flexi Light whitening system, DENT’N Co., France) for 4 minutes []. Bleaching procedure was repeated one more time for 8 minutes. The bleaching agent was removed by means of moist cotton followed by rinsing with air water spray. Lightening of the teeth shade was noted and rubber dam was removed. All the treated teeth were polished using fine polisher (Compo Site, Shofu Inc, Japan) to obtain high luster. High gloss finish obtained after fine polishing, camouflaged white spots as well as remaining dark areas on the enamel surface []. The patient was informed regarding the likelihood of developing dentinal hypersensitivity, which would subside in a few days. The patient was prescribed the calcium sodium phosphosilicate-containing desensitizing tooth paste (Vantej™, Dr. Reddy's Laboratories Ltd., India) for 3 weeks and then discharged. At 1 month follow-up, the results were stable and the patient did not complain of any symptoms related to dentinal hypersensitivity [].
A 9-year-old boy was referred to the Department of Pediatric Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran. The patient needed comprehensive dental treatment due to amelogenesis imperfecta. At the same time his parents requested to treat his gingival pigmentation. His oral examination revealed that his gingiva is deeply pigmented from the right second primary molar to the left second primary molar (). He had been checked by a physician previously and there were no pathologic disorders (e.g. Albright syndrome, trauma, hemachromatosis and racial pigmentation) in this case. Therefore, we started depigmentation therapy by cryosurgery technique.\nLiquid nitrogen was provided in the morning of treatment day by a consumer gas factory and was transferred to the dental facility. In order to transfer the liquid nitrogen, it had been saved in a two-layer flask (metallic inner layer and glassy outer layer).\nIn the first step isolation was instated by suction and cotton rolls; then hyperpigmentation areas were dried byair spray and 10% topical lidocaine gel was used to achieve anesthesia. During treatment, liquid nitrogen was poured into the glass mug and was rolled on the pigmentation area by cotton swabs (). After the gingiva blanched, the operation was started in another area; after 20 seconds this process was repeated. It is possible repeat this process three or four times for each area. The total time needed for this operation was 30 minutes. In order to record and analyze the results, five standard photos were taken in different positions. Standard high-quality images were taken at baseline and after one, three, six and twelve months (). All the photos were taken by a Canon digital camera (Ixus 800IS, Japan) in the same position, while the patient was sitting upright, and the distance between patient and camera was fixed to about 30 centimeters.\nMinimal reddish erythema was observed after cryosurgery. After one month the gingival color was ideal. No complications were observed during the follow-up. No recurrent lesions were observed in 12-month follow-up ().