Quintessence International, 12/1990

A computerized method of codifying dental lesions and treatment is presented to enable faster identification of victims of catastrophes. Each tooth is assigned a bidigital value. The first digit refers to the root and designates weather it is found to be perfect, damaged and/or treated, or absent. The second digit refers to the crown and is assigned according to the number of surfaces showing lesions or treatment. For the identification of corpses, missing individuals whose record reveals values less than or equal to those of the subject in every tooth (or of each quadrant in cases of doubt) are selected for consideration from the data base. Individuals who have even one tooth with a value greater than that of the subject are eliminated.

Awareness of normal and abnormal variation of the internal anatomy of the teeth is essential for clinical success. Three cases in which maxillary premolars were found to have three roots and the subsequent endodontic therapy are described.

The purpose of this study was to evaluate a dentinal bonding system through a follow-up investigation over a 2-year period of clinical performance. An experimental composite resin and the dentinal bonding system were applied to 108 teeth. Each restoration was examined at baseline, 1 week, 1 month, 3 months, 6 months, 1 year, and 2 years. No secondary caries or severe pulpitis was detected at any of the recall examinations. Only nine of 108 restorations were found to be unacceptable after 2 years. The dentinal bonding system showed relatively good clinical results and may prove to be useful clinically.

A three-dimensional cavity design was used to study the morphology of dentin in vitro both after dentinal pretreatment and after restoration failure (debonding). Dentinal bonding agents that require removal of the smear layer (third generation), as well as those that depend on attachment to the smear layer (second generation), were included. Results indicated cohesive failures within both the dentinal bonding agents and the smear layer in second-generation systems. Dentinal conditioners for the third-generation dentinal bonding agents and for an as-yet unclassified agent were effective in removing smear layer debris from the dentinal surface, but they varied in the degree to which they opened the dentinal tubules. Differences in morphology of the dentinal surface following debonding of the restoration were attributed to differences in chemical composition among the agents examined.

Parents and guardians of Japanese infants attending a dental clinic for their first routine dental examination were surveyed about their attitudes toward and understanding of the effects of ion drinks. The survey questioned the experiences resulting from administration, motives for use of the drinks, time of starting use of the drinks, and understanding of the relationship between the drinks and dental caries. In addition, the hydrogen ion concentration of various ion drinks commercially available on the Japanese market were measured in relationship to cariogenicity. Slightly more than 70% of the infants had been given ion drinks. The most frequent reason for using the drinks was because it had been recommended by the pediatrician followed by the belief that it was good for the health. Seventy-five percent of the infants were taking the drinks before 1 year of age. Ten percent of the infants were given the drinks in a nursing bottle, and 58% of the guardians answered that the drinks had no deleterious dental effects, indicating their poor understanding of the situation. Most of the drinks had a highly acid hydrogen ion concentration (below pH 4), indicative of extreme cariogenicity.

The depth of cure of three light-cured glass-ionomer cements was examined immediately after polymerization under the curing light and 12 hours after polymerization. The duration of illumination was also varied among groups to determine its effect on the depth of cure. Light-Cured Zionomer showed a greater immediate depth of cure than did either Vitrabond or XR ionomer. All three materials demonstrated greater depth of cure 12 hours after application of the light source, indicating that they possess dual-curing characteristics. Increasing the duration of illumination from 30 to 60 seconds significantly (P .05) increased the depth of cure for all three materials.

A 2-rear study of the clinical performance of four posterior composite resins used for Class I and Class II restorations is reported. Seventy-seven obturations were reviewed from the patients selected for a previous 9-month study. Obturations were assessed macrophotographically and by scanning electron microscopic evaluation of marginal quality. The 2-rear results were compared to those obtained at 9 months. The macrophotographic evaluation revealed a satisfactory clinical appearance in the majority of restorations. However, scanning electron micrographic observations demonstrated that moderate-to-medium marginal degradation occurred during the first 2 years of clinical service. Therefore the use of the products under investigation should be limited to selected cases in which esthetics is of primary concern.

A new material to be used in the procedure of enamel microabrasion has been recently introduced. Because the compound contains hydrochloric acid, the manufacturer recommends many safety precautions, especially use of tile rubber dam. This case report documents the effect of the enamel microabrasion compound on the gingiva of one human subject and verifies the need for careful handling of the material.

Cast etched resin-bonded extracoronal attachments provide a new method of treatment for a partially edentulous, caries-free dentition. Electrochemically etched nonprecious retainers with extracoronal attachments are bonded with composite resin to caries-free unrestored abutment teeth to support a removable partial denture. The advantages of this technique are that little enamel is lost because preparation is minimal, restoration margins are supragingival, placement of the partial denture is excellent, and esthetics is satisfactory. The preparation of a resistance form, and thus the primary mechanical retention of the metal frame of the retainer, seems to be the main factor in long-term success. The absence of long-term results limits the use of this technique to carefully selected groups of patients.

Lichen planus is one of the most common dermatologic diseases involving the skin and oral mucous membranes. It may occur anywhere in the oral cavity. Erosive lichen planus has been reported to undergo malignant transformation, making definitive diagnosis, treatment, and followup essential. The purpose of this study was to establish the effectiveness of griseofulvin therapy on erosive lichen planus and to provide an alternative to steroid therapy. The results of this study revealed that griseofulvin had little or no effect on pain, pigmentation, or disappearance of erosive lichen planus and did not protect the patient from further recurrences.

Amelogenesis imperfecta is an inherited disorder involving enamel formation that affects the appearance of the teeth to various degrees. Cosmetic rehabilitation of these patients has been open to a variety of treatment options. Complete-coverage restorations are often recommended. Patients are occasionally averse to this because of the extensive preparation of tooth structure or lack of financial means. In the past, conservative measures here inadequate because the lack of enamel bonding did not allow a durable restoration. Presently, with the use of glass-ionomner cements and dentinal adhesives, dentin-resin bond strengths are approaching those of etched enamel. This article discusses the use of glass-ionomer cement, dentinal priming agents, and etched enamel to create a strong bond between restorative material and tooth structure that provides not only satisfactory esthetics, but also a durable restoration.

For centuries, chewing sticks have been used as a tooth-cleaning device. One of the most commonly used types is known as the Miswak. Despite its common use, few studies have examined possible effects on the gingiva and the surrounding structures. The purpose of this study was to examine the relationship between Miswak and periodontal health. The incisors, canines, and premolars were examined in 236 patients. All patients were interviewed regarding their demographic data, oral hygiene habits, and use of Miswak, Clinical examination included scoring of plaque, gingival inflammation, pocket depths, attachment loss, and gingival recession. Patients were divided into three groups: a Miswak group, a toothbrush group, and a Miswak/toothbrush group. The results of this study indicated that use of the Miswak may influence plaque accumulation and periodontal health.