Quintessence International, 07/2006

Talon cusp is a developmental dental anomaly, normally located on the palatal surface of the anterior teeth, that can occur in both primary and permanent dentition. The aim of this article is to relate a clinical case of talon cusp that interfered with both the occlusion and appearance of the patient. During anamnesis, the patient told of difficulty masticating. Clinical examination revealed labial inclination of the maxillary central incisors, featuring an overjet of about 5 mm, with interposition of the lower lip and an Angle Class I occlusal relationship. A treatment plan was devised in which gradual grinding of both talon cusps, the fitting of a removable orthodontic device, and clinical and radiographic follow-up were carried out. Keywords: clinical problems, complications, dental anomaly, diagnosis, talon cusp

Objective: Various bleaching modalities are now offered to patients, either monitored by the dental office or self-directed, for which relative efficacy is unknown. The aim of this in vitro study was to evaluate the ability of different bleaching products and protocols to lighten enamel and dentin. Method and Materials: Bovine tooth samples of standardized thickness (2.5 ± 0.025 mm with similar dentin and enamel thicknesses) were prepared and stained with whole blood and hemolysate before being submitted to 11 different bleaching regimens: home bleaching using 10%, 15%, 16%, or 20% carbamide peroxide, power bleaching using 15% hydrogen peroxide, 30% hydrogen peroxide, or 25% carbamide peroxide with or without light activation, and over-the-counter bleaching strips containing 5.3% hydrogen peroxide. Colorimetric measurements were performed on each sample side, according to the CIE L*a*b* system, before and after staining as well as after each series of 5 bleaching sessions (number of applications varied from 5 to 20 times, according to the bleaching protocol). Results: All products and protocols produced a similar bleaching effect on enamel, while the home bleaching regimen proved largely superior to lighten dentin. Conclusion: In-office bleaching techniques proved less efficient than home bleaching for removing stains deposited in dentin. Keywords: carbamide peroxide, home bleaching, hydrogen peroxide, in-office bleaching, power bleaching, tooth bleaching

Objective: This study aimed to determine the prevalence of early childhood caries (ECC) and severe early childhood caries (s-ECC) in inner-city children in Ghent, Belgium, and to investigate the independent impact of its determinants. Method and Materials: In a nonrandomized cross-sectional research design, all children between 24 and 34 months of age attending the final consultation at a participating Child and Family Health Clinic were included (n = 385). Data on oral hygiene and caries were collected by oral examination. Caries prevalence and oral hygiene were determined according to established criteria. Data on oral health habits and socioeconomic status were obtained by a validated questionnaire. All analyses were performed with ECC and s-ECC as response variables. Results: The mean DMFS was 0.83 (SEM = 0.14). ECC was diagnosed in 18.5% of the children and s-ECC was found in 12.2%. Treatment need was 100%. From the multiple regression analysis it became clear that ethnicity and neighborhood significantly determined ECC. From all oral health-related behavioral variables, only daily use of a bottle with sweetened drinks other than milk or water, frequency of brushing, and quality of oral hygiene as expressed by Plaque Index scores remained significantly associated with ECC. Conclusion: Children whose mothers had an Eastern European nationality at birth and who live in a deprived neighborhood, daily use a bottle with sweetened drinks other than milk or water, brush less than once a day, and have plaque are at higher risk for ECC and s-ECC. Keywords: early childhood caries, epidemiology, inner-city

Objectives: Remineralization of dentin by mucin-containing saliva substitutes might be inhibited by sialic acids bound to mucin, which are known to complex calcium. Thus, the aim of this investigation was to evaluate the effects of various mucin-containing solutions, differing in calcium phosphate concentrations, to be used as saliva substitutes on demineralized bovine dentin in vitro. Method and Materials: Bovine specimens (153) were embedded in epoxy resin, polished (4,000 grit), and partly covered with nail varnish (control of sound dentin). After demineralization for 14 days (pH 5.5), the specimens (n = 9) were exposed to 14 mucin-based solutions (30 g/L) at 2 different pH values (5.5 or 6.5) and differing in saturation with respect to apatites. Two fluoride-free solutions and the commercially available saliva substitute Saliva Orthana (Orthana, Kastrup) served as controls. Differences in mineral loss (DDZ) and lesion depth (DLD) between the values prior to and after storage in the various solutions were evaluated from microradiographs of thin sections (100 µm). Results: The general linear model revealed an almost significant dependency on calcium for DDZ (P = .050) and a significant dependency on calcium for DLD (P = .037). pH influenced DDZ significantly (P .001), whereas DLD was not influenced significantly (P = .169). Neither DDZ (P = .475) nor DLD (P = .703) were influenced significantly by phosphate. Conclusion: Even with low concentrations of calcium and phosphates, mucin-based saliva substitutes are capable of inhibiting demineralization of bovine dentin, whereas with solutions supersaturated with respect to apatites, a remineralizing effect could be observed. Keywords: calcium, dentin, mucin, phosphates, saliva substitute, solubility

Sinus tracts are paths of drainage for abscesses and can occur both intraorally and extraorally. It is a fact that sinus tracts can heal with proper endodontic therapy. However, there are those types that are persistent and will not respond to any treatment. In these perplexing cases, it may be necessary to elevate a surgical flap to unveil the real etiologic factor. In this article, a case is presented in which 2 persistent and nonhealing sinus tracts were observed around the maxillary left incisor area of a 53-year-old female patient. A difficult cast post-and-core removal had been accomplished to the compromised tooth 1 year previously. A surgical flap had to be reflected, and the cause of the persistent inflammation was determined to be 2 separate root perforations. The granulation tissue was removed, the perforations were sealed with mineral trioxide aggregate, and bone graft was packed in the resorptive bone areas. The symptoms subsided by the time of the 2-week recall. No complaints were noted from the patient during the 4-month follow-up period. This case is a good example that demonstrates the possible complications of post preparation and the necessity of explorative surgery for unveiling the etiologic factor of persistent sinus tract formation. Keywords: post and core, root canal therapy, root perforation, sinus tract

Objective: The aim of this study was to evaluate the clinical efficacy of home-administered vital bleaching procedures and possible adverse effects derived from their use. One gel containing 3.5% hydrogen peroxide with a 5% potassium nitrate component (FKD, Kin Lab) was compared with a carbamide peroxide-based gel with a concentration of 10% (Opalescence, Ultradent). Method and Materials: Two sample groups were designed, each composed of 8 patients. All patients employed both bleaching products, 1 in the maxillary arch and the other in the mandibular arch on a random basis. The treatment was applied for 3 hours a day for 4 weeks. The degree of bleaching was evaluated using the Vita guide arranged by brightness. Dental sensitivity was measured with a specially designed 4-point scale. Gingival irritation was registered by the presence or absence of lesions in the marginal gingiva related to treatment. Results: The degree of bleaching was similar with both products (4.8 Vita shade tabs). The hydrogen peroxide product with potassium nitrate provoked less dental sensitivity, although the difference between the 2 products was insignificant (P = .063). Gingival irritation appeared in 6 subjects, but was unrelated to the applied product. Conclusion: Under the conditions of this study, no statistically significant differences were detected between 3.5% hydrogen peroxide containing 5% potassium nitrate (FKD) and the 10% carbamide peroxide-based product (Opalescence). Keywords: carbamide peroxide, home bleaching, hydrogen peroxide, potassium nitrate

Objective: The purpose of this study was to evaluate the effect of cavity preparation using hand instruments and conventional rotary instruments on the bonding of glass-ionomer cements to formerly carious teeth. Method and Materials: In 2 experimental groups (12 teeth each with primary caries) caries was removed and cavities prepared using hand instruments according to the atraumatic restorative treatment (ART) technique or conventional rotary instruments. In the control group (12 caries-free teeth) Class 1 cavities were prepared using conventional instrumentation. Cavities in all teeth were restored with 1 of the commercial glass-ionomer cements designed for use with the ART technique, either Fuji IX (GC) or Ketac Molar (3M Espe). After 21 days of storage in physiologic saline at 37°C, 3 400-µm-thick slices from each tooth were stained using the Mallory method and evaluated using a light transmitting microscope. Results: In all samples, a region of interaction was observed between the cement and dentin and enamel. However, the interface in teeth from which caries had been removed was different from that in the control group. All were stained using Mallory staining, but only teeth which had been carious showed coloration. No differences were found in intensity of color or appearance between the cavity preparation techniques. Conclusion: The occurrence of caries in a tooth alters the bonding behavior of glass ionomers to that tooth. The method of caries removal (ART or conventional preparation) does not influence the quality of the interface between a glass ionomer and either dentin or enamel. Keywords: atraumatic restorative treatment (ART), bonding, glass-ionomer cement, interfaces, tooth preparation

Polymorphous low-grade adenocarcinoma (PLGA) is a subtype of salivary gland carcinoma with a marked predilection for the minor salivary glands. The diagnosis of this lesion can be a challenge in incisional biopsies because of its similarity to other salivary neoplasms and the difficulty of analyzing its infiltrative nature and neurotropism. Diagnosis can be facilitated, however, by immunohistochemistry, a technique that has become a fundamental tool to the pathologist. The purpose of this study was analyze the immunohistochemical aspects of 4 cases that were examined in the São José dos Campos School of Dentistry. The patients included 4 women, ages 32 to 57 years (mean, 50 years), who reported an intraoral painless lesion, ranging in size from 1 to 3 cm (mean, 1.75 cm) with a variable evolution period. Histologically, the lesions showed similar aspects, characterized by polymorphous growth pattern, including solid, cribriform, trabecular, papillary, and "single-file" arrays. The tumors showed positivity to cytokeratins (Cks) 7 and 8 and vimentin, variable expression for Ck 14, and a negative reaction to Cks 13 and 19 and muscle-specific actin. PLGA is a tumor of the salivary gland that must be distinguished from other neoplasms for therapeutic and prognostic considerations, and the panel of antibodies employed in this study was effective for its diagnosis. Keywords: cytokeratins, polymorphous low-grade adenocarcinoma, salivary gland, vimentin

The fabrication of meatal obturator prosthesis with titanium framework using a 1-step final impression procedure is described in the case of a 44-year-old woman with congenital absence of the soft palate. The meatus obturator results in a more stable maxillary prosthesis and permits acceptable speech for a patient with total absence of the soft palate. The fabrication technique is relatively easy and saves time by eliminating some laboratory procedures. Keywords: cleft palate, meatus obturator, 1-step impression, soft palate, speech-aid prosthesis, titanium framework