RESUMO
This study aimed to analyze the effects of laser irradiation on the membrane integrity and viability of stem cells from human exfoliated deciduous teeth (SHED) that were kept in serum starvation. Nutritional deficit was used to mimic the cellular stress conditions of SHED isolation for regenerative dental approaches, where laser therapy could be beneficial. SHED were cultured under serum starvation (MEMα + 1%FBS) for 1 or 24 h pre-irradiation (protocols A and B, respectively). Then, cells received low-level laser therapy (LLLT; 660 nm) at 2.5 J/cm2 (0.10 W; groups I and V), 5.0 J/cm2 (0.20 W; groups II and VI), 7.5 J/cm2 (0.30 W; groups III and VII), or remained non-irradiated (groups IV and VIII). During irradiation, cells were maintained in 1% FBS (groups I-IV) or 10% FBS (normal culture conditions; groups V-VIII). Membrane integrity was evaluated by quantifying lactate dehydrogenase (LDH) release (immediately after irradiation), and cell viability was assessed by the MTT assay (24, 48, and 72 h post-irradiation). Serum starvation did not alter LDH release by non-irradiated SHED, while LDH release decreased significantly in groups irradiated in 1% FBS (I and III), but not in groups irradiated in 10% FBS (V-VII), regardless the pre-irradiation conditions (protocols A/B). Cell viability was significantly higher 24 h after irradiation, in most protocol A groups. In contrast, cell viability remained mostly unaltered in protocol B groups. LLLT contributed to maintain membrane integrity in SHED subjected to nutritional deficit before and during irradiation with 0.10 or 0.30 W. Short serum starvation before irradiation improved SHED viability at 24 h post-irradiation.
Assuntos
Membrana Celular/metabolismo , Lasers , Fenômenos Fisiológicos da Nutrição , Células-Tronco/patologia , Células-Tronco/efeitos da radiação , Esfoliação de Dente/patologia , Dente Decíduo/efeitos da radiação , Membrana Celular/patologia , Membrana Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Humanos , L-Lactato Desidrogenase/metabolismo , SoroRESUMO
Permanent maxillary central incisor impaction is a rare condition of multifactorial etiology that should be treated on diagnosis. This article describes multidisciplinary treatment of an 11-year-old patient presenting with a permanent maxillary right central incisor that was impacted due to the presence of 2 supernumerary teeth. The diagnosis was reached through clinical evaluation, radiography, and cone beam computed tomography. Treatment involved the surgical removal of the supernumerary teeth followed by traction of the impacted tooth through a combination of removable and fixed orthodontic appliances. Orthodontic treatment was completed after 18 months, resulting in adequate positioning of the right central incisor in the arch. Periodic follow-up visits were scheduled for prophylaxis and oral hygiene reinforcement. After 2 years, the teeth were adequately aligned, the gingiva was healthy, and the patient was esthetically satisfied. The multidisciplinary approach allowed functional and esthetic oral rehabilitation, thus helping the patient to avoid the psychological impact of a missing anterior tooth.