1,721,095 research outputs found
Dimensional accuracy of resultant casts made by a monophase, one-step and two-step, and a novel two-step putty/light-body impression technique: an in vitro study.
No full textDimensional accuracy when making impressions is crucial to the quality of fixed prosthodontic treatment, and the impression technique is a critical factor affecting this accuracy.
PURPOSE:
The purpose of this in vitro study was to compare the dimensional accuracy of a monophase, 1- and 2-step putty/light-body, and a novel 2-step injection impression technique.
MATERIAL AND METHODS:
A stainless steel model with 2 abutment preparations was fabricated, and impressions were made 15 times with each technique. All impressions were made with an addition-reaction silicone impression material (Aquasil) and a stock perforated metal tray. The monophase impressions were made with regular body material. The 1-step putty/light-body impressions were made with simultaneous use of putty and light-body materials. The 2-step putty/light-body impressions were made with 2-mm-thick resin-prefabricated copings. The 2-step injection impressions were made with simultaneous use of putty and light-body materials. In this injection technique, after removing the preliminary impression, a hole was made through the polymerized material at each abutment edge, to coincide with holes present in the stock trays. Extra-light-body material was then added to the preliminary impression and further injected through the hole after reinsertion of the preliminary impression on the stainless steel model. The accuracy of the 4 different impression techniques was assessed by measuring 3 dimensions (intra- and interabutment) (5-mum accuracy) on stone casts poured from the impressions of the stainless steel model. The data were analyzed by 1-way ANOVA and Student-Newman-Keuls test (alpha=.05).
RESULTS:
The stone dies obtained with all the techniques had significantly larger dimensions as compared to those of the stainless steel model (P<.01). The order for highest to lowest deviation from the stainless steel model was: monophase, 1-step putty/light body, 2-step putty/light body, and 2-step injection. Significant differences among all of the groups for both absolute dimensions of the stone dies, and their percent deviations from the stainless steel model (P<.01), were noted.
CONCLUSIONS:
The 2-step putty/light-body and 2-step injection techniques were the most dimensionally accurate impression methods in terms of resultant casts
Rare and life-threatening complication after an attempted lower third molar extraction: Lemierre syndrome
Full text linkLemierre’s syndrome is also known as the forgotten disease, and is a rare but life-threatening complication that can arise after surgical extractions of infected mandibular third molars. Owing to its rarity, oral and maxillofacial surgeons might not immediately recognise or can underestimate the pathological signs, and consequently do not apply the appropriate therapy to treat the syndrome. Here, we report on the occurrence and management of a case of Lemierre’s syndrome, where the complications affected the right sigmoid sinus. Since the condition appear to be underreported and not properly highlighted, eventual systematic review and meta-analysis of the occurrence of the Lemierre’s syndrome are highly recommended
An evaluation of the action of different root canal irrigants on facultative aerobic-anaerobic, obligate anaerobic, and microaerophilic bacteria
No full text-The aim of this study was to test the effect of different concentrations of sodium hypochlorite, chlorhexidine, and cetrimide on the following bacterial strains: Facultative aerobes-anaerobes: Candida albicans ATCC 10231; Enterococcus faecalis ATCC 29212; Escherichia coli ATCC 25,922; Pseudomonas aeruginosa ATCC 27,853; Streptococcus mitis ATCC 9811; Streptococcus mutans ATCC 35668; Streptococcus salivarius ATCC 13419; and Streptococcus sanguis ATCC 10556. Microaerophiles: Actinobacillus actinomycetemcomitans ATCC 29522. Obligate anaerobes: Actinomyces odontolyticus ATCC 17929; Fusobacterium nucleatum ATCC 25,586; Porphyromonas gingivalis ATCC 33277; and Prevotella melaninogenica ATCC 25845. Each irrigant was kept in contact with the bacterial species used for the experiment for 10, 20, or 30 min. Results showed that all irrigants had a bactericidal effect on both facultative aerobes-anaerobes and on microaerophilic and obligate anaerobic strains, in all concentrations and even after short periods of contact
Risk/prevention indicators for the prevalence of dental caries in schoolchildren: results from the Italian OHSAR Survey.
No full textThe Italian Oral Health of Schoolchildren of the Abruzzo Region (OHSAR) Survey was designed to assess indicators associated with the prevalence of caries in both the primary and permanent dentitions in the same schoolchildren, and it comprised a representative sample of 5,938 7-, 9- and 11-year-old schoolchildren from three provinces within the region of Abruzzo, Italy, a low fluoride concentration area. Gender, age, geographic location, socioeconomic level, dietary and oral hygiene habits, and the use of F supplements were all considered as indicators. The subsequent multivariate analyses showed that the socioeconomic level, snack consumption frequency, consumption of sweets and the use of F supplements were mostly associated with caries prevalence in both dentitions. Other indicators, such as gender, age, geographic location, between-meal snack consumption frequency, consumption of sweet drinks, toothbrushing frequency and onset of regular toothbrushing habits also showed some significant associations with dental caries across the age groups and/or dentitions. Of interest, the consumption of commercial bottled mineral water was also seen to be a preventive indicator for dental caries of the primary dentition, particularly in the 7-year-old group. The consumption of sweet snacks, use of interdental floss and kind of toothbrush mainly used (manual or electric) did not show any relevant association with the outcomes. The strong effect of the geographic location, socioeconomical level and the preventive effects of commercial bottled mineral water are worth further investigation
Analisi del rugosimetro di cavità dentarie preparate con diversi tipi di strumenti rotanti
No full text
Root canal treatment in mandibular canines with two roots: a report of two cases
No full text-AIM:
To highlight anatomical variation in the mandibular canine.
SUMMARY:
Two clinical case reports are presented to illustrate anatomical variation in the human mandibular canine. Endodontic treatment may sometimes fail because morphological features of the tooth adversely affect the treatment procedures. Many investigators have reported the anatomical variations associated with mandibular canines. Mandibular canines are recognized as usually having one root and one root canal in most cases, although approximately 15% may have two canals or sometimes two roots. This paper describes two clinical cases of mandibular canines with two roots and two canals.
KEY LEARNING POINTS:
Failure to control infection in the root canal system has an adverse impact on outcome. Clinicians should be aware of anatomical variations in the teeth they are managing, and should never assume that canal systems are simple. The majority of mandibular canines have one root and root canal, but 15% may have two canals, and a smaller number may have two distinct roots
A positioning device for computed tomography: a clinical report. .
No full textThis clinical report describes a device (Centrascan) used to assist in the correct alignment of the patient's head during computed tomography (CT) assessment of a proposed implant site. To obtain the desired anatomic detail, CT requires precise alignment of the axial images at right angles to the long axis of the proposed implant. This clinical report compared the anatomic morphology of a projected implant site derived from axial images provided by DentaScan software analysis of the CT scan acquisition. Images from a conventional scan, with the patient's head aligned along the frontal plane (perpendicular to the Frankfort plane) and along the sagittal plane (coinciding with either the cortical bone of the hard palate or the inferior border of the mandible), were compared with images acquired by use of the Centrascan device. The two scans differed substantially. In particular, the cross-sectional images obtained by the conventional procedure showed a distorted anatomy; conversely, the images obtained by the Centrascan procedure showed a better reproduction of the examined area. The Centrascan device seemed to help the radiologist achieve a more correct alignment of the patient's head during CT scan acquisition. Further studies are necessary to fully explore the relative technical merits of the Centrascan device
- …
