A study of the septa in the maxillary sinuses and the subantral alveolar processes in 30 patients

The objective of this paper is to study the incidence of septa in the maxillary sinus and measure the height of the underlying alveolar process using panoramic radiography and computerized tomography (CT scans). Thirty patients who were going to be treated with dental implants were submitted to panoramic radiographs and CT scans. Sixty maxillary sinuses were analysed and divided into 2 groups: group 1 (totally edentulous) and group 2 (partially edentulous). The sinuses were divided into 3 regions (anterior, middle, and posterior), the septa were analysed, and the heights of the alveolar processes were calculated in these 3 areas. Of the 30 patients, 36.5% had maxillary sinuses, and 25% of these sinuses had septa, and 11.8% of the panoramic radiographs were false-negatives. In the panoramic radiographs of 10 patients, 3 had bilateral septa, 5 had a septum in only one sinus, and 2 patients had 2 unilateral septa. In the CT scans of 11 patients, 4 patients had a bilateral septa, 5 had a septum in only 1 sinus, and 2 patients had 2 unilateral septa. Therefore, 2 more septa were observed in the CT scans. In the study of the height of the subantral alveolar process, the least amount of difference between both techniques occurred in the middle region of the sinus. The CT scan is more reliable than the panoramic radiograph in diagnosing maxillary septa because of its greater accuracy. In the panoramic radiograph, the middle portion of the alveolar process in the posterior subantral segment was the least distorted of the three portions measured.     

Three-dimensional aspects of etched enamel in non-erupted deciduous teeth

Acid etching with phosphoric acid on the prismless layer of human dental enamel may produce different patterns of dissolution. Consequently, the presence of several patterns of enamel acid conditioning may indicate better or worse formation of resin tags. In this study, the heterogeneous patterns of 35% phosphoric acid conditioning of human non-erupted deciduous teeth were reported. SEM images demonstrated type I, type II and type III aspects reported by Silverstone et al. (Caries Research 1975; 9:373-387), in spite of the etching time used and the surface area (buccal incisal, middle or cervical thirds). These characteristic features on the enamel surface may indicate the convenient use of this technique in deciduous teeth.     

Tooth loss and associated risk indicators in an adult urban population from south Brazil

The aim of the present study was to assess the prevalence, extent, and risk indicators of tooth loss in a representative adult, urban population in the Brazilian state of Rio Grande do Sul. A sample of 974 subjects (ages 30 to 103 years, mean 48.7, SD 13.4) representative of the metropolitan area of Porto Alegre, Brazil was selected by a multi-stage probability cluster sampling strategy. In all, 94% of the subjects had experienced tooth loss. The mean tooth loss was 11.2 teeth, and varied between 5.5 and 20.2 teeth in the 30-39 and 60 + years age groups, respectively. The multivariable analysis, adjusted for age, showed that subjects who had lost 7-13 or > or = 14 teeth were more likely to be females (odds ratio (OR) = 1.4, 2.4), of low (OR = 2.8, 5.1) or middle socio-economic status (OR = 2.3, 3.4), and heavy smokers (OR= 2.0, 2.3) than those with 6 or fewer missing teeth. Furthermore, loss of > or = 14 teeth was associated with presence of > 50% teeth with attachment loss > or = 5 mm (OR= 5.7), and loss of 7-13 teeth was associated with presence of > 50% teeth with attachment loss > or = 5 mm (OR = 2.4) and having 15-30% or > 30% decayed-filled teeth (OR = 2.7 and 4.1). In conclusion, tooth loss is highly prevalent in this urban Brazilian population. Gender, socio-economic status, cigarette smoking, caries experience, and attachment loss are important risk indicators. A reduction in the population's tooth loss may be achieved by the implementation of community programs for the prevention and treatment of dental caries and periodontal diseases.     

Inferior alveolar nerve damage because of overextended endodontic material: a problem of sealer cement biocompatibility?

Damage to the inferior alveolar nerve is a relatively infrequent complication in dental practice. When root canal treatment of a lower molar or premolar surpasses and/or overextends beyond the apical foramen and invades the periapical zone, the foreign material introduced within such a sensitive anatomical space may mechanically or even chemically affect the inferior alveolar nerve. We describe a case of endodontic treatment of a permanent right lower first molar in which the sealer cement overextended in large amounts and damaged the right inferior alveolar nerve. The condition reverted a few months after the surgical removal of the material. Evaluation of the removed material, using powder x-ray diffraction and scanning electron microscopy with coupled dispersive energy spectroscopy, showed it to consist of calcium tungstate (scheelite [CaWO4]) and zirconium oxide (baddeleyite [ZrO2]), which were chemical components of the sealer cement.     

Chemoluminescence generation and MTT dye reduction by polymorphonuclear leukocytes from periodontal disease patients

Alterations of polymorphonuclear leukocytes (PMNs) functions have been reported in patients with severe forms of some periodontal disease. In this study we evaluated the chemoluminescence generation and MTT dye reduction by human PMN in patients with juvenile periodontitis (JP), rapidly progressive periodontitis (RPP) and adult periodontitis (AP) during protein kinase C (PKC) activation or during the phagocytosis of opsonized zymosan. The results demonstrated that only PMNs of JP patients showed a decreased chemoluminescence generation and MTT dye reduction during the phagocytosis of opsonized zymosan (p < 0.05). The time to reach the maximal peak during the PKC activation on the chemoluminescence reaction was evaluated and JP PMNs patients demonstrated a depressed value (7.0 ± 0.4 min) compared with healthy volunteers (13.8 ± 0.5 min). The etiology and importance of such cellular alterations in the immunopathogenesis of the periodontal disease are discussed.     

A functional interleukin-1 beta gene polymorphism is associated with chronic periodontitis in a sample of Brazilian individuals

BACKGROUND: Interleukin-1 beta (IL-1 beta) is a potent inflammatory mediator and an important polymorphism in the locus +3954 (C/T) of the human IL1 B gene has been shown to affect the levels of this cytokine. This functional polymorphism has been associated with the establishment of inflammatory diseases, including periodontal disease, in European, Asian and North American populations. OBJECTIVE: The aim of this study was to investigate the association between the IL1 B (+3954) gene polymorphism and the occurrence of different clinical forms of periodontitis in a sample of Brazilian individuals. METHODS: This study employed a cross-sectional design involving individuals from the State of Minas Gerais in the south-eastern region of Brazil. Genomic DNA was obtained from oral swabs of 129 individuals and amplified using the polymerase chain reaction (PCR) with specific primers flanking the locus +3954 of IL1 B. PCR products were submitted to restriction endonuclease digestion and analyzed by polyacrylamide gel electrophoresis, to distinguish alleles T and C of the IL1 B gene, allowing for the determination of the genotypes and detection of the polymorphism. RESULTS AND CONCLUSIONS: The chronic periodontitis group displayed a higher percentage of the T allele (28%) when compared to the aggressive periodontitis group (10.7%, chi(2)=5.24, p=0.02, OR=0.31, CI=0.11--0.88) and to control group (8.7%, chi(2)=7.11, p=0.007, OR=0.24, CI=0.08--0.73). Our data suggested that the polymorphism in the locus +3954 of IL1 B gene could be a risk factor for chronic periodontitis in a sample of Brazilian individuals.     

Dental caries and microbial acid production in twins

OBJECTIVE: To determine the relative contribution of genetic and environmental stimuli on dental caries traits and microbial acid production in a twin model. METHODS: Dental caries examinations and microbial acid production assays were performed on 388 pairs of twins 1.5-8 years old from the city of Montes Claros, Brazil. Genotyping 8 polymorphic DNA markers determined zygosity. Caries exams followed NIDCR criteria modified to distinguish white spot lesions from cavitated lesions. Surface-based caries prevalence rates (SBCPR) were computed and lesion severity was determined by a weighted index (LSI). Biofilm samples were collected from the tongue using a lactic acid indicator swab. Assay scores were categorized based on acid formation as 1 = low, 2 = medium, and 3 = high. Heritability analyses were performed using the SOLAR software package. RESULTS: Heritability estimates for SBCPRs, LSI and for microbial acid production were H = 76.3 (p < 0.001), H = 70.6 (p < 0.001), H = 16.2 (p = 0.0078), respectively. Treating microbial acid production as a covariate in the SBCPR and LSI models did not significantly alter the heritability estimates, i.e. H = 76.5 (p < 0.001) and H = 70.8 (p < 0.001), respectively. CONCLUSIONS: These results suggest that variation in dental caries surface traits has a significant genetic contribution and that microbial acid production is modulated by the environment.     

Fixed rehabilitation of a patient with hypohidrotic ectodermal dysplasia using zygomatic implants

We found few references in the dental literature on implant rehabilitation of patients with hypohidrotic ectodermal dysplasia and only 1 case on zygomatic fixations and maxillary prosthesis in a patient with hypohidrotic ectodermal dysplasia. Two zygomatic fixations were placed according to the sinus slot technique, together with 3 implants in the anterior maxillary region. After 6 months, an upper complete prosthesis was screwed onto the implants, and lower overdentures were placed over the remnant canines. After 18 months of follow-up the patient reported important improvement in oral function and self-esteem.