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At least 649 records · Page 36Linked to original sources
PubMed2006

Predictable periimplant gingival esthetics: use of the natural tooth as a provisional following implant placement.

UNLABELLED: Maintaining the interdental papilla and bone height following implant placement has been a challenge for the restorative dentist. Bone resorption following anterior tooth extraction is common and often compromises the esthetics of the final restoration. The tissue must be maintained during the surgical and healing phases to achieve an esthetic outcome. Using the patient's natural tooth as a provisional can help maintain the volume and support the papilla. This article describes a technique to achieve maximum esthetics and preservation of tissue following tooth extraction and implant placement. CLINICAL SIGNIFICANCE: By using the patient's extracted natural tooth, the tissue should maintain itself with minimal recession. This will allow for a more esthetic outcome.

Dental Abutments↗
PubMed1994

Three-dimensional measurement study of the maximum protuberance and cervical line of the upper molars.

The maximum protuberance and the cervical line of 48 upper first molars and 56 second molars were observed using a three-dimensional measuring device. On the basis of the results, the relationship between the maximum protuberance and the cervical line was investigated on the respective contour line and lateral aspect waveform. The contour of the cervical line was positioned at the center of the maximum protuberance in both first and second molars. The distance of the lateral aspect between the measurement points of the maximum protuberance and the cervical line were wider in the mesiodistal direction than in the buccolingual direction. In the second molar, the distance between the maximum protuberance and the cervical line was narrower, and the stricture from the tooth crown to the cervical line on the second molar was decreased. The lateral aspect waveform of the cervical line and maximum protuberance tended to be similar, but the top-to-bottom distance of undulation on the maximum protuberance was longer than that of the cervical line. The buccolingual direction of the lateral aspect waveform showed much more marked fluctuations than that of the mesiodistal direction.

Female↗
PubMedDate not supplied

Direct cuspal-coverage posterior resin composite restorations: A case report.

The clinical success of direct composite restorations is the result of the correct use and performance of adhesive systems, resin composites and light curing systems. Total-etch adhesive systems and microhybrid resin composites have seen continuous improvement; various clinical techniques have been introduced to address polymerization shrinkage. Manufacturers have introduced sophisticated light-curing devices with the hope of improving performance. Direct resin bonded composites (RBCs) are becoming the first choice in many clinical situations. This article presents an experimental clinical technique that outlines the reconstruction of severely damaged posterior teeth missing multiple cusps; particular attention to incremental and curing techniques is adopted to complete each restoration.

Acid Etching, Dental↗
PubMed2000

Application of high resolution microfocus X-ray CT for the observation of human tooth.

The calcification degree of extracted human teeth was observed by using high resolution microfocus X-ray CT. As samples, upper and lower first premolars extracted from a 21-year-old female were used. The computed tomograms were produced by high resolution microfocus X-ray CT with a open vacuum X-ray source, rotating sample stage, and image sensor. The distinction between enamel and dentin was very clear, and the shape of the pulp cavity was also clearly identified. The secondary dentin was visible in the circumpulpal dentin. The color map displays showed the heterogeneity of the calcification degree not only in the dentin but also in the enamel. The enamel was divided into three layers according to the calcification degree. High resolution microfocus X-ray CT was very useful for the observation of the internal structure of human teeth without destroying the samples.

Adult↗
PubMed2002

Anisotropy of tensile strengths of bovine dentin regarding dentinal tubule orientation and location.

The purpose of this study was to investigate the effects of the location and orientation of dentinal tubules in the tooth on tensile strengths of the dentin. Dumbbell-shaped specimens of 12 groups from various locations and dentinal tubule orientations were prepared. The tensile test was performed in distilled water at a temperature of 37 degrees C. The tensile strengths of the parallel to the orientation were significantly greater than those of the perpendicular to the orientation; the tensile strengths of the radicular dentin were significantly greater than those of the coronal dentin. Nevertheless, in the radicular dentin, the tensile strengths of the perpendicular to dentinal tubules differ with respect to tensile forces. These results suggest that tensile strength of the dentin varies according to the location and orientation of dentinal tubules in the tooth.

Analysis of Variance↗
PubMed2005

Biological aspects of tooth fragment reattachment in immature incisors.

Tooth fragment reattachment is a relatively new technique and there are many aspects which still need to be explored. Reported here is a case of enamel and dentin fracture of 11 and 21. There was a very thin layer of dentin clinically over the pulp chamber and the root apices were immature. The reattachment procedure was modified slightly. The initial joint was made with protective calcium hydroxide and glass ionomer cement on the approximating surfaces. The further reattachment was accomplished using composites and acid etch technique. This was done for pulpal protection. After six months, reattachment was intact and successful with no staining, sensitivity or pain. The radiographs revealed root completion of the immature incisors. The reattachment procedure proved to be biologically superior in addition to its esthetic value and psychological advantage.

Accidental Falls↗
PubMedDate not supplied

Comparative study of dimensional accuracy of different impression techniques using addition silicone impression material.

This study compared dimensional accuracy of the single, double with spacer, double with cut-out and double mix impression technique using addition silicone impression material. A typhodont containing Ivorine teeth model with six (6) full-crown tooth preparations were used as the positive control. Two stone replication models for each impression technique were made as test materials. Accuracy of the techniques were assessed by measuring four dimensions on the stone dies poured from the impression of the Ivorine teeth model. Results indicated that most of the measurements for the height, width and diameter slightly decreased and a few increased compared with the Ivorine teeth model. The double with cut-out and double mix technique presents the least difference from the master model as compared to the two latter impression techniques.

Dental Impression Materials↗
PubMed1999

Reattachment of a subgingivally fractured central incisor tooth fragment: report of a case.

A case report of a 9-year-old boy with a fractured maxillary right incisor and ulcerated pulp at the fracture line is presented. On satisfactory completion of a root canal filling one week later, the access cavity was restored with glass ionomer cement. The fragment was reattached by a light activated hybrid composite during the flap surgery. Tetracycline hydrochloride was applied on open root surface for a better healing.

Bisphenol A-Glycidyl Methacrylate↗
PubMedDate not supplied

Prevalence of pre-eruptive intracoronal dentin defects from panoramic radiographs.

PURPOSE: This investigation stemmed from preliminary clinical observations from a school dental clinic, which suggested that a proportion of clinically undetected, radiolucent lesions on radiographs may originate as pre-eruptive intracoronal dentin defects. This study investigated the prevalence of such defects in orthopantomograms from a group of children and young adults. METHODS: A total of 1281 orthopantomograms with 11,767 unerupted permanent teeth were examined. RESULTS: The prevalence of intracoronal dentin defects was 3% by subjects, and 0.5% by teeth; the highest prevalence being noted in the maxillary and mandibular first permanent molars. Most of the lesions occurred singly, and nearly half had extended to greater than two-thirds the width of dentin thickness. Ectopic positioning was significantly associated with this lesion. CONCLUSIONS: Pre-eruptive intracoronal dentin defects occur at a significant prevalence rate. Increased awareness of this entity may improve diagnosis and allow early treatment.

Chi-Square Distribution↗
PubMed1999

[Management of an impacted canine tooth in the palate].

The abundance of scientific articles about current dental movements such as intrusion, space closure, uprighting ... is in contrast with the rarity of those concerning palatal impacted canine. The goal of this article is to emphasize upon frequent hazards of this dysmorphosis which often generate litigations and to suggest an original classification of favorable and unfavorable clinical situations and a simplified mechanotherapy.

Cephalometry↗
PubMed1976

[Cracks in the dental enamel caused by sensitivity testing with CO2 snow and dichloro-difluoromethane--a comparative in vivo study].

With the aid of permeating dye and standardized fluorescence UV-photography, the reaction of subjects and enamel to the application of two pulp vitality testing methods (frozen carbon dioxide and Frigen -pellets) was examined. The enamel lamella system, the diffusion of temperature changes through the tooth crown and the thermodynamic pattern of enamel and dentine are described in detail. Structural changes of enamel as well as the subject's reaction times to a cold stimulus during the vitality tests are documented and the data are compared. Frigen caused less enamel changes than did frozen carbon dioxide. The subject's reaction times were similar for both methods. There were no differences between the methods with regard to the number of reopened, extended and newly created enamel fissures. However, the length, width and depth of these fissures proved to be less pronounced for Frigen than for carbon dioxide. Clinical implications of the results are discussed.

Cold Temperature↗
PubMedDate not supplied

Cuspal deflection of maxillary premolars restored with bonded amalgam.

The aims of this study were to measure cuspal deflection of premolars restored with bonded amalgam and to investigate bond resistance to thermo-cycling and cyclic loading. Strain gauges were used to measure cuspal deflection of maxillary premolars restored with MOD bonded amalgam restorations. A nondestructive method was used in which teeth were loaded repeatedly to record cuspal deflection following different restorative procedures. Ten extracted premolars with similar dimensions were selected and their roots mounted in resin bases 2 mm below the CEJ. Two single-element strain gauges were bonded to the buccal and lingual surfaces of the cusps of each tooth at a level that corresponded to the pulpal floor of MOD cavities. These were connected to a strain indicator with a built-in wheat-stone bridge. An Instron machine was used to apply a 100 N compressive load. Micro-strain readings were recorded with each loading at the following stages: (1) sound unprepared teeth (baseline reading), (2) following preparation of a medium-size MOD cavity, (3) 24 hours following restoration with amalgam, (4) following amalgam removal, (5) 24 hours following restoration with bonded amalgam. Durability of the bond was further tested by cyclic loading of 2000, 4000, 6000, and 8000 load cycles. Mean micro-strain values recorded at the buccal cusp were: 48.0 (21.6), 126.8(57.2), 121.4(53.3), 120.8(56.1), and 65.2(36.5) for test stages 1, 2, 3, 4, and 5 respectively. Cuspal deflections following cyclic loading recorded at the buccal cusp were: 60.0(41.0), 63.6(51.9), 59.6(36.3), and 61.6(36.8) at the above four cyclic loading stages respectively. A similar trend was also observed for measurements of the lingual cusp. It was concluded that bonding amalgam restorations decreases cuspal deflection and consequently may assist in restoring tooth strength under conditions of the oral environment.

Analysis of Variance↗
PubMedDate not supplied

Cuspal reinforcement in endodontically treated molars.

UNLABELLED: This in vitro study compared the ability of horizontal pins and a dental adhesive to reinforce the facial cusps of endodontically treated mandibular molars. Seventy-two mandibular molars were divided into six groups and mounted in acrylic blocks (n = 12). In Groups 1-5 standardized endodontic access and instrumentation in the coronal one-third of each root canal were completed. In Groups 1-4 the lingual cusps were reduced, leaving the buccal cusps intact. The facial cusps of the teeth in each group received one of the following modes of reinforcement: Group 1--no reinforcement; Group 2--dentin adhesive (Amalgambond Plus); Group 3--two horizontal TMS Minim pins; Group 4--two horizontal TMS Minim pins and Amalgambond Plus. Teeth in Group 5 were prepared for and restored with a complete cuspal coverage amalgam restoration using four vertical TMS Minim pins. Group 6 consisted of intact natural teeth. Using an Instron Universal Testing Machine, the lingual slope of the facial cusp of each specimen was loaded to failure using a compressive force applied at an angle 60 degrees to the long axis of the tooth. The mean fracture strengths for all groups were analyzed using a one-way ANOVA and Student-Newman-Keuls multiple range test (alpha = 0.05). Fracture patterns and modes of failure were also evaluated. RESULTS: The intact teeth (Group 6) were significantly more fracture resistant than all other groups, with the exception of Group 4 (combination of pins and adhesive). Group 1 (non-reinforced teeth) was significantly weaker than all other groups. Groups 2-4 (specimens with reinforced cusps) were not significantly different from each other. The use of horizontal pins or a combination of horizontal pins plus dentin adhesive for cuspal reinforcement resulted in significantly more teeth demonstrating favorable fracture patterns than did the use of adhesives alone. CONCLUSION: The buccal cusps of endodontically treated mandibular molars reinforced with a combination of horizontal pins and dentin adhesive were not significantly weaker than intact teeth. Of the restored teeth, those which had buccal cusps reinforced with horizontal pins and those treated with complete cuspal coverage amalgam restorations exhibited the most favorable restorative prognosis following cusp fracture.

Chi-Square Distribution↗
PubMedDate not supplied

Radiographic evaluation of third-molar development in a group of Turkish children.

The aim of this investigation was to evaluate the crypt formation and calcification of the maxillary and mandibular third molars according to age and gender on panoramic radiographs in a group of Turkish children. Four hundred panoramic radiographs of 188 female and 212 male dental patients, ages six to thirteen years, were examined by two observers. The interrater reliability was tested by Kappa statistics. The earliest age for maxillary third molar crypt formation was eight years; mandibular third molars could be seen radiographically as early as seven years.

Adolescent↗
PubMed2000

Treatment of trauma to the primary and young permanent dentitions.

An overview of the various possibilities for trauma to the primary and young permanent dentition has been presented. Appropriate treatment procedures have been described. Advances in dental science have been great, and dental materials have become superior to what they were just a few years ago. The dentist must never forget the variabilities of human responses to any of the treatment techniques, however, and the dentist must never be dogmatic in approach. The dentist should be able to diagnose, interpret, and alter any of the treatment techniques as more scientific evidence is obtained.

Child↗
PubMedDate not supplied

Pre-eruptive intracoronal resorption as an entity of occult caries.

"Occult" or "hidden" caries refers to occlusal caries which is not diagnosed clinically because the occlusal surface appears ostensibly intact, and radiographs show radiolucencies in dentin. The prevalence of occult caries has been reported to range from 2.2% to over 50% of permanent molars. In spite of its relatively high prevalence, the etiology and pathogenesis of occult caries remain unclear. The author hypothesizes that occult lesions could have resulted from processes which are pre-eruptive or post-eruptive. Pre-eruptive processes include intracoronal resorption of unerupted teeth, and the post-eruptive process is occlusal fissure caries. Although the prevalence of intracoronal resorption has been shown to be around 3-6% by subject and 0.5-2% by teeth, the percentage contribution of this process to the overall prevalence of occult caries is unclear. When affected teeth are fully erupted, it is difficult to determine if pre-eruptive resorption had been present previously. The prevalence of occult lesions does not appear to be affected by fluoride exposure. Radiographs are useful adjuncts to aid in the diagnosis of occult lesions. Bitewing radiographs are useful for detecting early occlusal fissure caries while panorex radiographs of unerupted developing teeth aid in the diagnosis of pre-eruptive intracoronal lesions. It is suggested that all unerupted, developing teeth on radiographs be examined for pre-eruptive resorptive lesions.

Adolescent↗