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A hiperpigmentação melânica ocorre devido à deposição anormal de melanina na camada basal e suprabasal do epitélio, criando uma aparência escurecida. É fisiológica, por isso não representa dano à saúde, podendo ser apenas uma queixa estética do paciente. O objetivo deste trabalho foi realizar uma revisão de literatura narrativa sobre o uso da técnica cirúrgica com bisturi, da abrasão com instrumento rotatório e da ablação com laser como métodos para realizar a remoção da hiperpigmentação melânica gengival de etiologia fisiológica. Muitas técnicas têm sido utilizadas para fazer a despigmentação, diferentes resultados e fatores, como conforto do paciente, cuidado pós-operatório e recorrência, têm sido apresentados. A técnica cirúrgica com bisturi é considerada o padrão ouro devido aos seus bons resultados, material de fácil acesso e baixo custo. A abrasão com instrumentos rotatórios não requer nenhum equipamento ou material sofisticado, é relativamente simples e segura. E a terapia a laser é uma modalidade de tratamento eficaz, minimamente invasiva, com trans e pós-operatório confortável. Entretanto, são necessários mais estudos sobre o uso da abrasão com instrumento rotatório que acompanhem os pacientes em longo prazo e pesquisas que descrevam o uso e resultados proporcionados pelos diversos tipos de laser de alta potência. Tendo em vista a presente revisão de literatura pode-se concluir que a repigmentação não ocorre por uma média de um a dois anos. Porém, são necessários mais estudos para especificar qual técnica apresenta menor índice de repigmentação.

Melanic hyperpigmentation occurs due to abnormal deposition of melanin in the basal and suprabasal layers of the epithelium, creating a darkened appearance. It is physiological, so it does not represent harm to health, and may be just an aesthetic complaint by the patient. The objective of this work was to carry out a narrative literature review on the use of surgical technique with a scalpel, abrasion with a rotary instrument and laser ablation as methods to remove gingival melanin hyperpigmentation of physiological etiology. Many techniques have been used to perform depigmentation, different results and factors, such as patient comfort, postoperative care and recurrence, have been presented. The surgical technique with a scalpel is considered the gold standard due to its good results, easily accessible material and low cost. Abrasion with rotary instruments does not require any sophisticated equipment or material, is relatively simple and safe. And laser therapy is an effective treatment modality, minimally invasive, with comfortable trans and postoperative. However, more studies are needed on the use of abrasion with a rotary instrument to monitor patients in the long term and research that describe the use and results provided by the different types of high-power lasers. In view of the present literature review, it can be concluded that repigmentation does not occur for an average of one to two years. However, further studies are needed to specify wich technique has the lowest rate of repigmentation.

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Background: Zinc-doped hydroxyapatite has been proposed as a graft biomaterial for bone regeneration. However, the effect of zinc on osteoconductivity is still controversial, since the release and resorption of calcium, phosphorus, and zinc in graft-implanted defects have rarely been studied. Methods: Microspheres containing alginate and either non-doped carbonated hydroxyapatite (cHA) or nanocrystalline 3.2 wt% zinc-doped cHA (Zn-cHA) were implanted in critical-sized calvarial defects in Wistar rats for 1, 3, and 6 months. Histological and histomorphometric analyses were performed to evaluate the volume density of newly formed bone, residual biomaterial, and connective tissue formation. Biomaterial degradation was characterized by transmission electron microscopy (TEM) and synchrotron radiation-based X-ray microfluorescence (SR-µXRF), which enabled the elemental mapping of calcium, phosphorus, and zinc on the microsphere-implanted defects at 6 months post-implantation. Results: The bone repair was limited to regions close to the preexistent bone, whereas connective tissue occupied the major part of the defect. Moreover, no significant difference in the amount of new bone formed was found between the two microsphere groups. TEM analysis revealed the degradation of the outer microsphere surface with detachment of the nanoparticle aggregates. According to SR-µXRF, both types of microspheres released high amounts of calcium, phosphorus, and zinc, distributed throughout the defective region. The cHA microsphere surface strongly adsorbed the zinc from organic constituents of the biological fluid, and phosphorus was resorbed more quickly than calcium. In the Zn-cHA group, zinc and calcium had similar release profiles, indicating a stoichiometric dissolution of these elements and non-preferential zinc resorption. Conclusions: The nanometric size of cHA and Zn-cHA was a decisive factor in accelerating the in vivo availability of calcium and zinc. The high calcium and zinc accumulation in the defect, which was not cleared by the biological medium, played a critical role in inhibiting osteoconduction and thus impairing bone repair.

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OBJECTIVE: The aim of this preclinical study was to compare histologically and histomorphometrically both sandblasted/acid-etched implant surfaces with or without maintained in an isotonic solution of 0.9% sodium chloride in early stages of osseointegration. MATERIAL AND METHODS: Both implant surfaces were composed of a titanium/aluminum/vanadium alloy (Ti6Al4V-ELI), but they had different surface chemistries: sandblasted/acid-etched titanium surface (FN) or sandblasted/acid-etched surface maintained in an isotonic solution of 0.9% sodium chloride (FA). The surface morphology, topography and chemistry were evaluated by scanning electron microscopy (SEM), confocal microscopy (CM) and X-ray photoelectron spectroscopy (XPS), respectively. Dynamic contact angle (DCA) was employed for wettability evaluation. One implant from each group was placed in the left tibia of twenty healthy, skeletally mature Santa Ines sheep (n = 5). Bone area (BA) and bone-to-implant contact (BIC) were performed on thin sections (30 µm) at 7, 14, 21 and 28 days after implant installation. RESULTS: Despite the roughness and morphology similarities between the groups, at the XPS evaluation, the FA group presented 2.3 times less carbon on the surface (FN: 27.3% and FA: 11.6%), sharply enhanced hydrophilicity and significantly enhanced BA and BIC at 14, 21 and 28 days of healing (P < 0.05) compared with the FN. CONCLUSION: The data suggest that the hydrophilic FA accelerates the BA apposition and BIC interface around the implants during early stages of bone formation, providing highest degree of osseointegration.

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Double tooth and talon cusp are tooth shape anomalies with rare co-occurrences in a single tooth. Double tooth is a developmental anomaly that leads to the eruption of fused teeth and may contribute to compromised esthetics, pain, caries, and tooth crowding. Talon cusp is a rare developmental extra cusp-like projection on the cingulum area that may cause functional and esthetic problems. Differential diagnosis of these anomalies may be complicated. A multidisciplinary approach for the esthetic and functional rehabilitation of double teeth is important. Various treatment methods have been described in the literature for the different types and morphological variations of double teeth. The purpose of this paper is to report the case of an unusual combination of double tooth and talon cusp on a permanent maxillary incisor and describe its esthetic and functional rehabilitation using a porcelain laminate veneer.

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OBJECTIVE: The aim of this study was to evaluate the histopathologic changes in dental pulp of teeth with chronic advanced periodontitis. METHODS: In 22 patients, 30 teeth were selected for inclusion. Patients had received no periodontal treatment. No teeth had caries, abrasion, attrition, erosion, trauma, or restoration. Radiographically, all teeth showed bone-support destruction to the apex. Thermal and cavity tests were used to evaluate pulp vitality. After tooth extractions, crowns were separated from roots at the cementoenamel junction. Both the crowns and the roots were prepared for histopathologic analyses. Radicular pulp was analyzed considering both coronal and apical halves. RESULTS: In 100 percent of the cases, coronal pulp exhibited soft connective tissue. In the coronal half of radicular pulp, soft connective tissue was present in 60 percent of the cases, fibrosis in 30 percent, and fibrosis associated with dystrophic calcification in 10 percent. In the apical half of radicular pulp, 6.6 percent of the cases demonstrated fibrosis; 23 percent exhibited fibrosis associated with pulp atrophy and secondary dentin; and 63.3 percent showed fibrosis, pulp atrophy, secondary dentin, and diffuse calcification. CONCLUSION: Radicular pulp of teeth with chronic periodontitis presents characteristics compatible with pulp changes resulting from pulp aging. In such cases, endodontic treatment is not indicated to enhance periodontal treatment results.

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