Quintessence International, 05/2005

Amelogenesis imperfecta is a hereditary condition resulting in poor tooth development, severe anomalies, or complete absence of enamel. Enamel lesions may be the only characteristic of this condition or may be part of a generalized syndrome. Amelogenesis imperfecta can be characterized by enamel hypoplasia and/or hypomaturation or hypocalcification of the existing teeth. Restoration for patients with this condition should be oriented toward the functional and esthetic rehabilitation and the protection of the existing teeth. This paper presents a description of a patient's oral rehabilitation with all-ceramic veneers and crowns after extensive crown lengthening. The diagnostic procedure is also reported in detail. A microscopic examination was also performed on an extracted third molar under polarized light. Keywords: all-ceramic restorations, amelogenesis imperfecta

Objectives: The aim of this in vitro study was to investigate the antibacterial activities of different generation dentin-bonding systems. Method and materials: The antibacterial activities of dentin-bonding systems Optibond FL Primer, Single Bond, Clearfil SE Bond Primer, and Prompt-L-Pop were evaluated against Streptococcus mutans, Streptococcus salivarius, Lactobacillus casei, and Lactobacillus acidophilus. Cervitec (1% chlorhexidine varnish) was also examined as a positive control material. Disk diffusion tests with filter paper disks (n = 10) containing a drop of each material (20 µL) were used. After incubation at 37°C for 48 hours, the growth inhibition zones were measured in millimeters. Results: Of all the materials tested, Optibond FL Primer, Clearfil SE Bond Primer, and Prompt-L-Pop showed larger growth inhibition zones than the control material for all bacterial strains. No antibacterial effect was noted for Single Bond. The results indicated that Optibond FL Primer had the strongest effect against the S mutans and L casei, and Clearfil SE Bond Primer produced the largest inhibition zone for S salivarius and L acidophilus among the test materials. Conclusion: The antibacterial effects observed for the tested different generation dentin-bonding systems may be related to the acidic nature of the materials. Keywords: antibacterial activity, dentin-bonding systems

Patients with congenitally missing teeth (hypodontia) present with complex problems. Meeting their treatment needs requires a joint effort between the disciplines of orthodontics and restorative dentistry. There are a number of options available to restore space generated by missing teeth. In the majority of patients orthodontic treatment will be required before this space can be restored satisfactorily. The second part of this series reviews the orthodontic considerations for various options. Keywords: anchorage, hypodontia, missing teeth, orthodontics, prosthesis, space closure

Objectives: The objective of this study was to assess the effect of a one-bottle bonding agent on sealant success after 3, 6, 12, and 24 months. Method and materials: The sample group consisted of 30 schoolchildren (8 to 10 years of age) who had all their permanent first molars sound and unsealed. Occlusal sealants were placed on first molars according to a split-mouth design. Sealant scoring occurred at 3, 6, 12, and 24 months and was performed by two clinicians blinded to the treatment group. Fisher's exact test was used to analyze the data. Results: The clinically acceptable marginal integrity rates for sealants with a bonding agent after 3, 6, 12, and 24 months were 93%, 93%, 83%, and 79%, respectively. For sealants without a bonding agent, the clinically acceptable marginal integrity rates after 3, 6, 12, and 24 months were 90%, 88%, 81%, and 77%. The rates for no color change in sealants with a bonding agent after 3, 6, 12, and 24 months were 96%, 93%, 81%, and 75%, respectively. For sealants without a bonding agent, the no color change rates after 3, 6, 12, and 24 months were 93%, 93%, 79%, and 72%. After 24 months, 73% of the sample group were available for recall. The retention rates for sealants with and without a bonding agent after 24 months were 79% and 75%, respectively. The results of the statistical analysis showed that there were no differences among the sealants with and without bonding agents evaluated in relation to marginal integrity, marginal discoloration, and anatomic form. Conclusion: The success of a sealant is related to whether the sealant is applied under optimal conditions. The results of this study show that at the 2-year mark, the placement of a bonding agent under sealants did not significantly affect the clinical success of sealants. Keywords: anatomic form, bonding agents, marginal discoloration, marginal integrity, sealant application, sealant evaluation, sealants

Objectives: This study measured the water flow commonly used in high-speed handpieces to evaluate the water flow's influence on temperature generation. Different flow speeds were evaluated between turbines that had different numbers of cooling apertures. Method and materials: Two water samples were collected from each high-speed handpiece at private practices and at the School of Dentistry at São José dos Campos. The first sample was collected at the customary flow and the second was collected with the terminal opened for maximum flow. The two samples were collected into weighed glass receptacles after 15 seconds of turbine operation. The glass receptacles were reweighed and the difference between weights was recorded to calculate the water flow in mL/min and for further statistical analysis. Results: The average water flow for 137 samples was 29.48 mL/min. The flow speeds obtained were 42.38 mL/min for turbines with one coolant aperture; 34.31 mL/min for turbines with two coolant apertures; and 30.44 mL/min for turbines with three coolant apertures. There were statistical differences between turbines with one and three coolant apertures (Tukey-Kramer multiple comparisons test with P < .05). Conclusion: Turbine handpieces with one cooling aperture distributed more water for the burs than high-speed handpieces with more than one aperture. Keywords: high-speed equipment, high-speed cavity preparation, pulp pathology

Objective: The purpose of this clinical study was to evaluate SureFil packable resin composite for posterior restoration of permanent teeth for a period of 3 years. Method and materials: Fifty-five resin composite restorations were placed in 36 patients (16 Class I and 39 Class II restorations). After cavity preparation, the enamel was etched with 34% phosphoric acid. Prime & Bond NT was applied 20 seconds to dentin and etched enamel and cured for 20 seconds. The teeth were restored in 3- to 5-mm increments. The restorations were assessed after placement, at 6 months, 1 year, 2 years, and 3 years for color stability, marginal discoloration, marginal adaptation, secondary caries, surface texture, anatomic form, and postoperative sensitivity according to Ryge's criteria. The changes in the parameters were assessed with Friedman test analysis with a Bonferroni correction at a significance level of .05. Results: Forty of the monitored 47 restorations were classified as excellent after 3 years. Thirty-one restorations were graded Bravo at baseline for color match. At the 3-year assessment (n = 47) the color of the 31 restorations had not changed. Two restorations (same patient) were lost after 1 month and were scored as Charlie until the end of the study. After 3 years there were five Bravos and one Charlie with marginal discoloration, five Bravos with marginal adaptation, and three Bravos with anatomic form (P < .05). Conclusion: After 3 years of clinical service, SureFil packable resin composite, with a failure rate of 6%, was considered to be successful in Class I and II restorations. Keywords: clinical performance, packable resin composite, Ryge's criteria

Objectives: Resilient denture-lining materials are more susceptible to microbial adhesion than are denture base acrylic resin. As denture hygiene is essential to maintain the serviceability of the denture, disinfectant solutions have been suggested as a method for effectively cleaning resilient liners. The aim of this study was to determine the effectiveness of four different disinfectant solutions on four different resilient lining materials contaminated with Staphylococcus aureus, Streptococcus sobrinus, and Candida albicans. Method and materials: Three microorganisms (Sta aureus, Str sobrinus, and C albicans), four resilient lining materials (Tempo, Immediate, Flexacryl soft, Ufi Gel P), and four disinfectant solutions (5.25% sodium hypochlorite, 2% sodium hypochlorite, 5% Deconex, and 3.5% Savlex solutions) were investigated. The four resilient lining materials were contaminated with each of the microorganisms, then the disinfection tests were applied to detect the efficacy of disinfectant solutions on resilient denture base materials in an in vitro test. The specimens (n = 5, total = 240) were soaked for 5 minutes in each solution to disinfect the microorganisms. The control specimens (one of each material; n = 5, total = 60) were soaked in distilled water for 5 minutes. As a result, a reduction in microorganism counts was determined. The Kruskal-Wallis and one-way analysis of variance tests were used to analyze for significant differences among test groups at the level of significance. Results: For all microorganisms, soaking in 5.25% sodium hypochlorite reduced the number of viable adherent microorganisms significantly compared to soaking in 2% sodium hypochlorite, which led to greater reduction than soaking either 5% Deconex or 3.5% Savlex. The use of 5.25% sodium hypochlorite in all groups is statistically significant. Conclusion: Disinfection of four different resilient denture-lining materials with 5.25% sodium hypochlorite solution was the most effective immersion technique. To achieve an efficient disinfection, the immersion time of the other disinfectant solutions could be increased. Keywords: disinfection, microbiology, microorganism, resilient soft-lining materials

Chemotherapy may be either an effective alternative to surgery or a valuable adjunct to surgery and/or radiotherapy in the treatment of cancer. The care of medical oncology patients is a multidisciplinary effort. Oral health care providers can expect to be called on to care for patients with cancer undergoing chemotherapy. Early, active participation in developing preventive and therapeutic strategies, in implementing the plan, and in the education and rehabilitation of patients is paramount in addressing quality of life issues. To provide timely and competent care, oral health care providers must understand the disease, its treatment, and the impact the disease and/or its treatment may have on these patients. Oral health care providers should develop and implement preventive and therapeutic strategies with the same ethical, moral, and professional standards of care as may be appropriate in the management of any other patient. Keywords: cell cycle, chemotherapy, hemorrhage, infection, mucositis, oral management, xerostomia