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At least 559 records · Page 31Linked to original sources
PubMed2000

Macroscopic and microscopic analysis of the palato-gingival groove.

With the objective of correlating the anatomical aspects of the palato-gingival groove with its etiology, diagnosis, and alternative treatments, 13 permanent maxillary incisors with palato-gingival grooves were selected from a large sample and subjected to macroscopic and microscopic analysis of groove morphology. The palato-gingival groove occurred most frequently on the lingual aspect of the lateral incisor (11 of 13), and its coronal and radicular extensions were on the disto-lingual surface of the incisors (7 of 13 and 6 of 13, respectively). Deformation of the contour of the pulp cavity was noted subjacent to the groove (9 of 13), along with diminished enamel and dentin thickness (11 of 13 and 13 of 13, respectively) and an increase in cement (12 of 13). The groove was observed extending to the apical third in nine specimens, and a direct communication between the pulp and periodontium was observed in only one case. From these examinations it is concluded that the palato-gingival groove can be clinically diagnosed, preventing subsequent problems; however microscopic analysis of the affected tooth is necessary to allow precise evaluation of the groove's extension and damage to the dental structure.

Dental Cementum↗
PubMed2001

In vitro longitudinal assessment of coronal discoloration from endodontic sealers.

A major cause of tooth discoloration may be sealer remnants in the chamber. The objective of this study was to evaluate, longitudinally, coronal discoloration from four sealers. Extracted premolars were sectioned in the coronal third of the root. The chamber contents were removed and instrumentation was via the canal. The following sealers were bulk introduced into the chamber: AH26, Kerr Pulp Canal Sealer, Roths 801 (nonstaining), and Sealapex. The apical access was sealed with white sticky wax. Teeth were maintained in a moist environment at 37 degrees C. Initial (immediate pretreatment) digital images of the teeth were made for base line comparison. Subsequent images were at 1-, 3-, 9-, and 12-month intervals. Then images were mixed and descriptively evaluated blindly by trained evaluators. Discoloration was induced by the four sealers, with slight to moderate visible changes that increased through 12 months. There was slightly more discoloration with AH26 and Kerr Pulp Canal Sealer. In conclusion discoloration induced by the endodontic sealers produced slight to moderate and generally progressive discoloration over 12 months.

Bicuspid↗
PubMed2002

Sealer distribution in coronal dentin.

A major cause of tooth discoloration is sealer remnants in the pulp chamber after root canal treatment. The purpose of this study was to assess coronal distribution and color changes of four commonly used sealers placed in the pulp chamber after 2 yr. Fifty extracted premolars were cross-sectioned in the coronal third of the root. The chamber contents were removed, and instrumentation was via the canal; then freshly mixed sealer was placed in each chamber. Sealers evaluated were: AH 26, Kerr Pulp Canal Sealer, Roth 801, and Sealapex. The apical access was sealed with white sticky wax, and the tooth was maintained in a moist environment at 37 degrees C for 2 yr. Teeth were split longitudinally, and digital images of the exposed dentin were made, scrambled, and evaluated blindly by trained evaluators for color changes and for presence of sealer in dentin. There was no measurable penetration of sealer into dentin for all groups and no dentin discoloration occurred. The sealers displayed marked discoloration. At 2 yr, the sealers discolored and remained confined primarily to the pulp chamber.

Bismuth↗
PubMed2004

Radiographic evaluation of root canal multiplicity in mandibular first premolars.

The purpose of this study was to examine the accuracy of radiographic evaluation of root canal multiplicity in mandibular first premolars in vitro. One hundred thirty-nine extracted human mandibular premolars were used. Buccolingual radiographs were taken, and the number of canals in each tooth was determined on radiographs by four dentists using a view box. A sudden narrowing of the main canal was interpreted as a sign of multiple canals. After the radiographic evaluation, the tooth crown was removed. India ink was injected into the root canal system, and the root was cleared to observe the canal morphology. There was no statistically significant difference among the four dentists with respect to the coincidence rate (93%-96%) of the canal number evaluated on radiographs with that identified by cleared teeth observation (p > 0.05, one-way analysis of variance). A sudden narrowing of the main canal on the radiograph was a good criterion to judge root canal multiplicity.

Analysis of Variance↗
PubMed2004

Effect of gingiva on laser doppler pulpal blood flow measurements.

The purpose of this study was to evaluate the effect of labial and palatinal gingiva on laser Doppler pulpal blood flow measurements. Twenty upper central incisor teeth determined to be vital from 20 volunteers were included into the study. To stabilize the probe, a laboratory-made acrylic splint positioned the probe labially on the cervical third of the tooth crown. We collected measurements without any gingival covering, and under three conditions: after application of an opaque paste on the labial gingiva, the palatal gingiva, or both the labial and palatal gingiva. The measurement values decreased 46% when there was opaque paste on labial gingiva, 10% on palatinal gingiva, and 63% on both. The decrease in the values when there was an opaque paste on palatinal gingiva was not statistically significant (p > 0.05). The differences between all other groups were statistically significant (p < 0.05). In these measurements, the contribution of labial gingiva to laser Doppler pulpal blood flow measurements is more than that of palatinal gingiva.

Adult↗
PubMed2004

Morphological measurements of anatomic landmarks in human maxillary and mandibular molar pulp chambers.

The aim of this in vitro study was to measure critical morphology of molar pulp chambers. One hundred random human maxillary and mandibular molars (200 teeth in total) were used. Each molar was radiographed mesiodistally on a millimeter grid. Using a stereomicroscope, the measurements were read to the nearest 0.5 mm. Results were as follows (mean, mm): pulp chamber floor to furcation, maxillary = 3.05 +/- 0.79, mandibular = 2.96 +/- 0.78; pulp chamber ceiling to furcation, maxillary = 4.91 +/- 1.06, mandibular = 4.55 +/- 0.91; buccal cusp to furcation, maxillary = 11.15 +/- 1.21, mandibular = 10.90 +/- 1.21; buccal cusp to pulp chamber floor, maxillary = 8.08 +/- 0.88, mandibular = 7.95 +/- 0.79; buccal cusp to pulp chamber ceiling, maxillary = 6.24 +/- 0.88, mandibular = 6.36 +/- 0.93; and pulp chamber height, maxillary = 1.88 +/- 0.69, mandibular = 1.57 +/- 0.68. The pulp chamber ceiling was at the level of the cementoenamel junction in maxillary, 98%, and mandibular, 97% of the specimens. The measurements showing the lowest percentage variance were buccal cusp to furcation (approximately 11%) and buccal cusp to pulp chamber ceiling (approximately 14%). The measurements were similar for both maxillary and mandibular molars.

Dental Pulp Cavity↗
PubMed2005

Endodontic management of dens evaginatus of maxillary central incisors: a rare case report.

Dens evaginatus is a disturbance in tooth development that produces a tubercle of hard tissue on the surface of the tooth. While prophylactic pulp capping is recommended for vital teeth, teeth with necrotic pulps require endodontic therapy or extraction. This rare case of a 24-yr-old Indian male with affected maxillary central incisors demonstrates the clinical consequences of dens evaginatus.

Adult↗
PubMed2005

Adhesive dentistry and endodontics: materials, clinical strategies and procedures for restoration of access cavities: a review.

The complexity of restorative dentistry has increased greatly in recent years, with the myriad of products used in "adhesive dentistry." So too has the "simple" matter of restoring access cavities after completion of endodontic treatment. This review discusses current methods of "bonding" to tooth structure, ceramic materials, and metals, with emphasis on those aspects that are important to endodontics. Specific materials, procedures and major decision making elements are discussed, as well as how to avoid problems in compatibility between endodontic and restorative materials.

Acid Etching, Dental↗
PubMed2005

Dynamic finite element analysis of the human maxillary incisor under impact loading in various directions.

The aim of this study was to investigate fracture patterns occurring when a human upper central incisor is subjected to impact loadings at various angles. A two-dimensional finite element (FE) model of the maxillary incisor and surrounding tissues was established. The structural damping factor for the tooth was then calculated and assigned to the model. Dynamic FE analysis was performed to stimulate the associated impacts. Time-dependent traumatic forces at 0 degrees, 45 degrees, and 90 degrees labially to the long axis of the tooth were applied to the model. Von Mises's equivalent stress contours within the FE models were calculated. Our results indicated that tooth damping lagged behind peak stress by 0.05 ms. In addition, we found that impact direction played an important role in terms of outcome for the fractured incisor. These results can, in part, explain the mechanisms underlying the alternative outcomes when upper incisors are subjected to impact.

Bite Force↗
PubMed1996

Resumed tooth development following avulsion of a permanent central incisor.

A case is presented in which an upper right central incisor was avulsed because of trauma at age six. At the time of trauma it was suspected that the pulp had remained in the socket although the tooth had been lost. No attempt was made to treat the socket, remove the pulp, or replant the tooth. Follow-up radiography showed that, despite initial apparent complete loss of the calcified portion of the tooth, root development proceeded to completion.

Child↗
PubMed2005

A temporary filling material may cause cusp deflection, infractions and fractures in endodontically treated teeth.

AIM: To test the hypothesis that Coltosol F might cause infractions and cusp fracture in root-filled teeth because of material expansion. METHODOLOGY: Thirty-two extracted human molar teeth were root filled and prepared with mesial-occlusal-distal (MOD) cavities with or without undercuts. The specimens were filled proximally with glass-ionomer cement and then occlusally with either Coltosol F or zinc oxide eugenol (ZOE). The tooth specimens were kept in water at 37 degrees C for a period of 20 days, and every second day the intercusp distance (ICD) of each specimen was measured in a travelling microscope, and the number of infraction lines as well as fractures were noted. RESULTS: The number of infraction lines increased in teeth filled with Coltosol F. Between day 8 and 16, seven of 16 teeth filled with Coltosol F showed fracture and exhibited a mean increase in ICD of 316 +/- 156 microm. Teeth filled with ZOE did not show an increase in number of infraction lines or in ICD, and none showed fracture. CONCLUSIONS: The hygroscopic expansion of Coltosol F in a cavity may lead to cusp deflection, infraction development and fracture. Masticatory forces will in vivo aggravate this unfavourable condition. The material is not recommended for temporary filling in root-filled teeth except for a few days.

Calcium Sulfate↗
PubMed2005

Talon cusp in a primary lateral incisor from a medieval child.

This paper describes talon cusp in an ancient skeleton and is a rare report of its occurrence in a primary lateral incisor. As well as talon cusp, the affected incisor also shows abnormal widening, probably representing a double tooth. There is also a supernumerary permanent incisor. The report shows that talon cusp existed in British populations more than 600 years before the first written description. A brief review of the literature on the occurrence of talon cusp in the primary dentition is presented.

England↗
PubMed2006

Dental findings of a child with Wolf-Hirschhorn syndrome.

The case presented is that of a 5-year-old female with Wolf-Hirschhorn syndrome. Dental findings were severe hypodontia, late dental development, taurodontism of the primary molars, microdontia, and spacing. Hypodontia has previously been reported and therefore this case adds to the evidence that hypodontia may be a common feature of this syndrome. It also suggests that other dental anomalies could occur in children with Wolf-Hirschhorn syndrome.

Abnormalities, Multiple↗
PubMed2006

Mixed dentition space analysis in a Jordanian population: comparison of two methods.

AIMS: To test the reliability of the Moyers charts and the Tanaka and Johnston equations in Jordanians and to derive coefficients of correlation between the combined mesiodistal widths of the four permanent mandibular incisors and the combined widths of the canine and premolars of the maxillary and mandibular quadrants. METHODS: The dental models of the dentition of 130 male and 96 female Jordanian subjects (age range is 14-16 years) with complete permanent dentition were randomly selected. The mesiodistal width of the four permanent mandibular incisors, maxillary and mandibular canines, and premolar teeth were measured using a vernier gauge caliper to the nearest 0.1 mm. The actual teeth measurements were then compared with the predicted values derived from the Tanaka and Johnston equations and Moyers probability tables. Correlation and linear regression analyses were performed between the predicted and actual tooth size for Jordanian children and standard regression equations were developed. RESULTS: Except for the maxillary arch in male subjects, Tanaka and Johnston regression equations underestimated the mesiodistal widths of permanent canines and premolars. On the other hand, there were no statistically significant differences between actual mesiodistal widths of canines and premolars and the predicted widths from Moyers charts at the 65% and 75% level for the lower and upper arches in male subjects and at the 85% level for the upper and lower arches in female subjects. For the newly developed regression equations, the correlation coefficients between the sum of the mandibular four incisors and the sum of the canine and premolars were 0.60 (for lower) and 0.51 (for upper) in male subjects and 0.59 and 0.64, respectively, in female subjects. CONCLUSIONS: (1) Tanaka and Johnston prediction method was not accurate when applied to a Jordanian population. (2) Moyers method for prediction can be used for Jordanian children at different probability levels for male and female subjects.

Adolescent↗
PubMed2007

Anomalies of tooth formation in hypohidrotic ectodermal dysplasia.

OBJECTIVE: The X-linked hypohidrotic ectodermal dysplasia (HED) is the most common type of ectodermal dysplasia. The clinical identification of possible heterozygous females can be difficult because of the varying degrees of clinical signs caused by X-chromosome inactivation. This study is the first to elaborate on anomalies of tooth formation found in a group of hemizygous males and heterozygous females with known ED1 mutations. These tooth anomalies may be used as dental biomarkers for heterozygous females, enabling an earlier diagnosis, and therefore, better treatment and genetic counselling. METHODS: Anomalies of tooth formation were examined using panoramic radiographs, dental casts and oral photographs in hemizygous males and heterozygous females who were identified by molecular genetic analysis. The results were compared to existing controls and normative data. RESULTS: All affected males had multiple missing permanent teeth and tooth malformations. The heterozygous females had a significantly higher frequency of agenesis of permanent teeth compared to normative data. The heterozygous females had an increased prevalence of tooth malformations and reduced tooth size, especially in the mesiodistal dimension. CONCLUSIONS: We conclude that observed anomalies of tooth formation may be used as dental biomarkers in the clinical identification of potentially heterozygous females.

Adolescent↗
PubMed2006

Anatomoradiographic description of the teeth of pacas bred in captivity (Agouti paca, Linnaeus, 1766).

Two newborn males, two adult males 9 and 72 months old, one newborn female and two adult females of 30 and 54 months old pacas were used. Animals were radiographed on lateral recumbency, teeth were extracted and the vestibulolingual and mesiodistal lengths were achieved at the occlusal surface, besides the longitudinal length. The lower incisors presented greater length in relation to the other ones and sinuous shape; the upper incisors, relatively smaller, are practically straight. There is no canine tooth, and after a great diastema there is one premolar and three molars in each hemiarcade. In adult pacas, the enamel of incisors presents yellowish colour, mainly in the labial surface; in the premolars and molars, the enamel is present as internal sheets disposed nearly in a parallel way and in vestibulolingual direction, through practically all the dental length, which provides several joined teeth aspect.

Animals↗
PubMed2004

Early loading (2 or 6 weeks) of sandblasted and acid-etched (SLA) ITI implants in the posterior mandible. A 1-year randomized controlled clinical trial.

UNLABELLED: The aim of this 1-year prospective controlled clinical trial was to evaluate the effect of early loading of ITI solid screw titanium implants with a sandblasted and acid-etched (SLA) surface on clinical and radiographic parameters. MATERIAL AND METHODS: Twenty-seven consecutively admitted patients presenting bilateral edentulous posterior mandibular areas and in need of prosthetic reconstruction were recruited. Sixty-seven ITI standard solid screw implants with an SLA surface, a diameter of 4.1 mm and a length of 8, 10 or 12 mm were installed bilaterally in molar and premolar areas according to a one-stage surgical protocol. One week (test) and 5 weeks (control) after implant placement, solid ITI prosthetic abutments were connected using a torque of 35 N cm. No provisional restoration was fabricated. Two weeks (test) and 6 weeks (control) after implant placement, porcelain-fused-to-metal single-tooth crowns were cemented. Clinical measurements were obtained at day 0 and 2, 6, 12, 24 and 52 weeks thereafter. Periapical radiographs were taken immediately after implant placement, after 6 weeks and at the 1-year examination. RESULTS: After 1 year, implant survival was 100%. Two test and one control implants rotated at the time of abutment connection and were left unloaded for 12 additional weeks. At the 1-year examination, no statistically significant differences were found between the test and control sites with respect to pocket probing depths (2.6 mm +/- 0.5 vs. 2.7 mm +/- 0.5), mean clinical attachment levels (3.1 mm +/- 0.4 vs. 3.2 mm +/- 0.5), mean percentages of sites bleeding on probing (9.7% vs. 8.3%), mean widths of keratinized mucosa (1.8 mm +/- 0.4 vs. 1.9 mm +/- 0.5), mean PerioTest values (-1.4 PTV +/- 0.9 vs. -1.6 PTV +/- 0.8) or mean crestal bone loss measurements (0.57 mm +/- 0.49 vs. 0.72 mm +/- 0.50). CONCLUSION: Based on these results, loading of titanium implants with an SLA surface as early as 2 weeks did not appear to jeopardize the osseointegration healing process in the posterior mandible. Furthermore, implants rotating at 35 N cm, if left unloaded for additional 12 weeks, did not negatively affect clinical and radiographic outcomes.

Adult↗