Quintessence International, 02/2002

Periodontal attachment loss in the maxillary anterior region can often lead to esthetic and functional clinical problems including disproportional and elongated clinical crowns, visible interdental embrasures, and altered linguoalveolar-labiodental consonant production. Assuming fixed prosthetic reconstructions will be chosen to treat these areas, it becomes a hygienic compromise to fill these areas in with porcelain. In the presence of these problems, an acrylic resin gingival veneer is an easily constructed, inexpensive, and practical device to optimize the esthetic and functional outcome in these special situations while permitting cleansibility of the prosthesis and supporting tissues. This article presents a step-by-step technique for the fabrication of a gingival veneer.

Objective: The purpose of this study was to compare the retentive strengths of resin, glass-ionomer, and zinc phosphate cements under adverse conditions. Method and materials: Thirty extracted teeth were mounted and prepared in their long axis. The axial wall height was 3 mm and the convergence angle was 28 degrees. These conditions increased the role of the cement and decreased the role of the preparation in providing retention of the casting. The axial surface area was determined. Copings were fabricated with a ring aligned in the long axis to facilitate removal of the crown. They were cemented with a resin cement, a glass-ionomer cement, or a zinc phosphate cement. A block randomization scheme was used to assign cements so that the mean surface areas of the teeth were equivalent in all groups. The copings were loaded in tension, and the amount of force required to remove the coping was recorded. The stress required to remove the coping was calculated. Results: The mean stress required to remove the copings was 9.4, 5.0, and 3.1 MPa for the resin, glass-ionomer, and zinc phosphate cements, respectively. Conclusion: The resin cement group was significantly stronger than both the glass-ionomer cement and the zinc phosphate cement groups. The glass-ionomer cement was significantly stronger than the zinc phosphate cement.

The extraction and reimplantation of teeth is a technique that has been practiced for many years, resulting in successful retention of teeth for up to 30 years. Although evidence confirming the advantages of this technique is limited, clinical observations and histologic examinations have revealed some important factors that are prerequisites for success: limitation of the time the tooth is exposed to the extraoral environment and preservation of vital periodontal tissue attachments on root surfaces. The latter goal can be achieved by gentle, atraumatic removal of the tooth from its socket, and hence the term exarticulation and reimplantation is more representative of the technique. In the present case report, a maxillary lateral incisor with a developmental defect was treated by exarticulation and reimplantation and application of calcium sulfate. Exarticulation and reimplantation seems to be a useful clinical procedure, but controlled studies are required to confirm its efficacy.

A young adult developed severe gingival recessions and radiographic signs of trauma to the periodontium after wearing a tongue barbell and a lip stud. Oral body art (piercing) can be hazardous to the periodontium; nevertheless, patients inclined to such practices do not see them as health hazards and are very reluctant to remove them.

Exposure of the dental pulp, through a caries lesion, accidentally during routine cavity preparation, or as a result of tooth fracture, is a clinical reality that requires optimal treatment. The potential for healing by formation of a dentinal bridge is good, provided that the pulp is not inflamed. Calcium hydroxide has a long history of inducing dentinal bridge formation to promote successful healing. Resin composites are emerging as alternative materials for pulp capping, but healing is slower, and relatively little clinical experience is available for analysis. The prognosis for healing is poor after exposure of an inflamed pulp. Pulpotomy should be considered to create a wound in an uninflamed location. If an exposure is expected through a caries lesion, stepwise excavation of the carious dentin should be considered to allow healing of the dentin and pulp prior to the final excavation of the carious dentin.

Objective: The aim of this study was to compare the microleakage of new all-in-one adhesive systems on enamel and dentin margins with that of a conventional total-etch system. Method and materials: Thirty buccal Class V cavities were prepared with enamel and dentin margins in 30 bovine teeth and randomly divided into three groups of 10 specimens each. Group 1 was bonded with Etch & Prime, group 2 with Prompt L-Pop, and group 3 with 35% phosphoric acid plus Prime & Bond 2.1. After being stored in an environment of 100% humidity for 24 hours, the teeth were immersed in a 50% silver nitrate solution for 24 hours and then put in a developing solution for 15 minutes. The specimens were sectioned vertically and buccolingually, and microleakage was evaluated on a scale of 0 to 3. Results: For the enamel margin, statistical analysis revealed that there was no significant difference between groups 1 and 2 or groups 1 and 3 but that there was a statistically significant difference between groups 2 and 3. Statistical analysis revealed no significant difference among the groups in dentinal microleakage. Conclusion: Among the three adhesive systems used in this study, Prompt L-Pop provided the least microleakage in enamel; however, there was no statistically significant difference among the groups on dentin margins.

Objective: In this in vitro study, the strength of several core and post-and-core systems was compared. A second aim was to compare the strength of posts and cores on root-filled teeth with that of cores on vital teeth. The failure modes of the core and post-and-core systems were also studied. Method and materials: For root-filled teeth, Composipost carbon fiber dowels and gold alloy posts and cores were tested. For vital teeth, glass-ionomer cement with threaded parapulpal retention pins, resin composite with threaded parapulpal retention pins, and gold alloy with parallel parapulpal pins were tested. Specimens were tested in a Zwick universal material-testing machine. Results: A significant variation in strength was found among core systems of cast gold, resin composite, and glass-ionomer cement constructed on vital teeth. The strength of the systems constructed on root-filled teeth did not vary significantly. The mode of failure varied, depending on the core or post-and-core material. Conclusion: Composipost posts and cores and cast gold posts and cores were equivalent in strength and did not vary significantly from gold cores constructed on vital teeth. The low strength values obtained for glass-ionomer cement in combination with threaded retention pins makes this combination a poor choice for core buildup.

Objective: Clinical, radiographic, and microbiologic changes in deep caries lesions were assessed after incomplete carious dentin removal and tooth sealing. Method and materials: Thirty-two teeth with deep caries lesions were studied. Treatment consisted of incomplete excavation of the demineralized dentin, application of calcium hydroxide, and sealing for a 6- to 7-month period. The color and consistency of the dentin were clinically assessed. Differences in radiographic density were assessed by digital image subtraction. Microbiologic samples were obtained from the demineralized dentin before the temporary sealing and after the experimental period. The samples were cultivated on blood agar under aerobic and anaerobic conditions, in Mitis Salivarius agar, and Rogosa selective Lactobacillus agar. Results: Two cases were lost during the study; one presented pulpal necrosis. In the other case, there was pulpal exposure during removal of provisional sealing. In all teeth, the initial demineralized dentin was soft and wet; one lesion was yellow, 21 were light brown, and eight were dark brown. After treatment, the dentin was dry, and 80.00% of specimens were hard, 16.67% were leathery, and 3.33% remained soft. The dentin was light brown in five teeth and dark brown in 25. There was a statistically significant mean difference in radiographic density (pixel intensity), 88.77 ±(plus/minus) 7.02 in the control areas and 94.66 ±(plus/minus) 6.75 in the test areas. The counts of anaerobic and aerobic bacteria, lactobacilli, and Streptococci mutans had decreased significantly by the end of treatment. Conclusion: Incomplete removal of carious dentin and subsequent tooth sealing resulted in the arrest of the lesions, suggesting that complete dentinal caries lesion removal is not essential to the control of caries lesions.