Human leukocyte antigen-G polymorphisms in periodontitis.

Objective: This study evaluated human leucocyte antigen-G gene polymorphisms in patients with periodontitis and healthy controls.Material and methods: The insertion/deletion polymorphism of 14 bp and a single nucleotide polymorphism (SNP) C > G on the position +3142 of the 3' untranslated region of the gene were analyzed in chronic periodontitis (n = 62), aggressive periodontitis (n = 24) patients and healthy individuals (n = 47).Results: Considering the 14 bp insertion/deletion, a significant deviation from Hardy-Weinberg expectations in the chronic periodontitis group was observed, but not in the other groups. No significant deviations were observed in patients and control groups considering the +3142 C > G SNP. A significant increased frequency of homozygotes for the 14 bp deletion allele was observed in the chronic periodontitis group as compared to controls. This group also presented a higher frequency of the deletion allele, which was marginally not significant. Concerning this polymorphism, no significant differences were observed between the aggressive periodontitis and healthy control groups. In addition, no significant differences were seen amongst patients and controls when considering the +3142 C > G frequencies.Conclusion: No differences were found amongst patients and controls when considering the +3142 C > G SNP haplotypes frequencies, but a significant increased frequency of homozygotes for the 14 bp deletion allele was observed in chronic periodontitis patients compared to healthy controls, suggesting a susceptibility role of this polymorphism in the pathogenesis of this condition.

Plasma cytokines levels in aggressive and chronic periodontitis.

OBJECTIVE: The present study evaluated the Th1/Th2 cytokine profile in plasma from healthy controls and different types of periodontitis patients. MATERIALS AND METHODS: The concentration of IL-2, IL-4, IL-5, IL-10, TNF-α and IFN-γ was determined in healthy controls (n = 18) and patients with chronic (n = 19) and aggressive periodontitis (n = 19) using a flow cytometric multiplex immunoassay. Means and standard deviations were calculated and compared using Kruskal-Wallis test. Spearman rho coefficient was used to correlate cytokines in the studied groups. RESULTS: Although there was no significant difference in the concentration of cytokines between groups, there was a tendency to lower levels of IL-5 and IL-10 in the aggressive periodontitis group. Stronger correlations were observed between IL-2/IL-4 and IL-2/IL-10 in healthy controls (0.938 and 0.669, respectively) compared with chronic (0.746 and 0.532) and aggressive periodontitis groups (0.395 and 0.266). When compared to healthy (0.812) and chronic periodontitis (0.845) groups, the correlation of IL-4/IL-5 was weaker in the aggressive group (0.459). CONCLUSION: No difference between systemic levels of Th1/Th2 was observed. In aggressive periodontitis patients, nevertheless, a trend towards low levels of Th2 cytokines could suggest a contribution to the development of such an exacerbated manifestation of this disease.

Tooth supported prosthetic rehabilitation in a 5-year-old child with early childhood caries.

This paper reports the case of a 5-year-old patient with early childhood caries (ECC) and presents an alternative prosthetic treatment with a tooth-supported overdenture. Primary canines were endodontically treated and received intraradicular posts with ball-type attachments to attach a tooth-supported overdenture. The patient was followed for 18 months both clinically and radiographically. In addition to esthetic and functional oral rehabilitation, the prosthetic treatment had an important psychological impact on recovery of patient's self-esteem.

Stem cells in dental practice: perspectives in conservative pulp therapies.

Stem cells are undifferentiated cells that have the capacity to self-renew. They have been discovered in many adult tissues, including teeth. The Dental Pulp Stem Cells are involved in dentinal repair by activation of growth factors, released after caries process and have the ability to regenerate the dentin-pulp-like complex. The molecular/cellular research raises the possibilities to grow new tissues and biological structures for clinical application, providing cells for therapies including cell transplantation and tissue engineering.

Root canals and apical foramina of the buccal root of maxillary first premolars with longitudinal sulcus.

In the present study, periapical radiographs were analyzed to investigate the number of canals of the buccal root of maxillary 1st premolars with longitudinal sulcus, and compare the number of apical foramina observed on the radiographs to that revealed by scanning electron microscopy (SEM). Thirty-nine human maxillary 1st premolars had their crowns and palatal roots removed and the root canals (C) were explored with endodontic files until the tip of the instrument was visualized exiting the apical foramen/foramina (AF). Radiographs were taken with files inside the root canals and the specimens were classified as follows: 1C/1AF; 2C/2AF; 1C/2AF; 2C/1AF. Apices were examined under SEM and the number of apical foramina (considering those measuring >80 microm in diameter) was recorded. Only 17.1% (n=6) of the specimens had 1C/1AF; 77.2% (n=27) had 2AF in which 42.9% (n=15) had 2C and 34.3% (n=12) had 1C; 5.7% (n=2) had 2C/1AF. SEM examinations showed that 46.1% (n=18) of the specimens had 2AF; 23.1% (n=9) had 1AF; 23.1% (n=9) had 3AF; 7.7% (n=3) had 4AF. Radiographic and SEM findings for the number of AF coincided in 62.8% of the cases. A buccal longitudinal sulcus in the maxillary 1st premolar is usually accompanied by total bifurcation (42.9%) or apical bifurcation (34.3%) of the root canal. SEM identified a statistically higher number of apical foramina than radiographs (p<0.01).

Estudo comparativo da morfologia da polpa dentária de dentes humanos submetidos à técnica de clivagem e a técnicas de descalcificação química / Comparative study of dental pulp morphology from human teeth submitted to cutting technique or chemistry decalcification technique

Os rápidos avanços do conhecimento acerca do reparo e regeneração tecidual, têm despertado o interesse pela biologia pulpar. Entretanto, para avaliar microscopicamente a dinâmica do tecido pulpar, é necessário, inicialmente, que o dente seja submetido aos processamentos histológicos de fixação e descalcificação. A descalcificação pode afetar o grau de coloração e pode causar desnaturação de proteínas. Além disso, é um processo demorado, visto que o dente requer um longo período de desmineralização. Assim, a proposta deste trabalho foi de avaliar qualitativamente a matriz extracelular e as células da polpa dentária, comparando três grupos: dois em que o tecido dentário foi descalcificado e um em que a polpa foi removida dos tecidos duros, não necessitando do processo de descalcificação. Dez pré-molares foram fixados em formalina tamponada a 10% por 24 horas. Após, estes dentes foram divididos em três grupos: 4 dentes foram submetidos a processo de descalcificação por meio de solução de Morse, 3 por meio de solução de EDTA a 10% e; os 3 dentes restantes tiveram sua polpa separada dos tecidos duros dentários por meio da técnica de clivagem. Na seqüência, os três grupos foram processados por meio da técnica histológica de rotina e foram corados com H/E. Os resultados desta análise demonstraram que houve uma melhor conservação tanto da matriz extracelular, quanto das estruturas celulares no grupo da clivagem, seguido do grupo Morse e por fim, com a menor conservação das estruturas pelo grupo EDTA.

The rapid advances of the knowledge of repair and regeneration tissues had proved to be an exciting time for pulp biology. However, to study the dynamic of pulp tissue, it is necessary, initially, that the tooth be submitted to histological fixation and decalcification processing. Decalcification may affect the degree of staining and it may cause denaturation of proteins. Furthermore, it is a slow process, demanding long demineralization times for a tooth. Thus, the purpose of the present study was to compare, qualitatively, the pulp extracellular matrix and the pulp cells, submitted to different techniques: EDTA solution decalcification, Anna Morse solution decalcification and a last group which pulp was removed from tooth without decalcification. Ten premolar teeth were fixed in 10% buffered formalin for 24 hours. After this, the teeth were divided in three groups: 4 teeth underwent decalcification with Morse solution; 3, decalcification with 10% EDTA solution and; 3, were sectioned and their pulps were gently removed. Subsequently, the groups followed the routine histological technique and staining with H/E. The results demonstrated that both conservation of pulp cells and extracellular matrix were better in the group without decalcification, followed by the Morse group and, the last, with the worst structures conservation for the EDTA group.

Root canals and apical foramina of the buccal root of maxillary first premolars with longitudinal sulcus

Avaliamos radiograficamente o número de canais da raiz vestibular de 1º pré-molares superiores com sulco longitudinal vestibular, e comparamos com microscopia eletrônica de varredura (MEV) quanto ao número de forames apicais (FA). As coroas e raízes palatinas de 39 dentes foram amputadas e os canais radiculares (C) explorados com lima endodôntica fina até suas pontas serem visualizadas apicalmente. As raízes foram radiografadas com as limas em seu interior e classificados pelo critério a seguir: 1C/1FA; 2C/2FA; 1C/2FA; 2C/1FA. Os ápices da raiz vestibular foram seccionados e preparados para MEV. Os números de FA (>80 µm) foram obtidos. A avaliação radiográfica demonstrou que 17,1% (n=6) das raízes apresentaram 1C/1FA 77,2% (n=27) tinham 2FA, sendo 42,9% (n=15) oriundos de 2C, e 34,3% (n=12) de 1C; 5,7% (n=2) apresentaram 2C terminando no mesmo FA. Em MEV, 46,1% (n=18) dos ápices apresentaram 2FA; 23,1% (n=9), apenas 1FA; 23,1% (n=9), 3 FA; e 7,7% (n=3), 4 FA. Houve correlação entre o diagnóstico radiográfico e MEV quanto ao número de FA em 62,8% dos casos. O sulco longitudinal vestibular no primeiro pré-molar superior predispõe à bifurcação total (42,9%) ou apical (34,3%) do canal radicular; sendo o método radiográfico estatisticamente inferior (p<0.01) à MEV no diagnóstico de FA.

Comparative analysis of two fixating and two decalcifying solutions for processing of human primary teeth with inactive dentin carious lesion

O objetivo deste estudo foi analisar qualitativamente a preservação das características teciduais pulpares de dentes decíduos ântero-superiores humanos com lesão cariosa de natureza inativa em dentina, comparando-se duas soluções fixadoras (paraformaldeído a 4% e formalina a 10%, ambos com tampão fosfato 0,1 M) e descalcificadoras [ácido fórmico/citrato de sódio – solução de Ana Morse e EDTA (ácido etileno diamino tetracético) a 10%]. Oito dentes foram subdivididos em 4 grupos (n = 2), variando-se o agente fixador e descalcificador. Grupo 1: paraformaldeído a 4% e solução de Ana Morse; Grupo 2: formalina a 10% e solução de Ana Morse; Grupo 3: paraformaldeído a 4% e EDTA a 10%; Grupo 4: formalina a 10% e EDTA a 10%. Os dentes foram fixados e posteriormente descalcificados até que uma consistência borrachóide fosse obtida. Cortes histológicos de 6μm de espessura foram corados com hematoxilina e eosina (H&E). A fixação com ambas as soluções demonstrou boa conservação tecidual, enquanto que a descalcificação com a solução de Ana Morse pareceu mais adequada, por requerer um menor tempo de processamento das amostras e promover uma melhor preservação dos componentes celulares e da matriz extracelular do tecido pulpar. O EDTA, além de exigir um tempo mais longo de processamento das peças, alterou as características morfológicas da polpa. A combinação formol a 10% – solução de Ana Morse pareceu ser favorável para a metodologia deste estudo.