Assessment of dental pulp response to carries via MR T2mapping and histological analysis.

OBJECTIVES: The aim of our study was to assess the correlation between T2 relaxation times and their variability with the histopathological results of the same teeth in relation to caries progression. MATERIALS AND METHODS: 52 extracted permanent premolars were included in the study. Prior to extractions, patients underwent magnetic resonance imaging (MRI) scanning and teeth were evaluated using ICDAS classification. Pulps of extracted teeth were histologically analysed. RESULTS: MRI T2 relaxation times (ms) were 111,9 ± 11.2 for ICDAS 0, 132.3 ± 18.5* for ICDAS 1, 124.6 ± 14.8 for ICDAS 2 and 112. 6 ± 18.2 for ICDAS 3 group (p = 0,013). A positive correlation was observed between MRI T2 relaxation times and macrophage and T lymphocyte density in healthy teeth. There was a positive correlation between vascular density and T2 relaxation times of dental pulp in teeth with ICDAS score 1. A negative correlation was found between T2 relaxation times and macrophage density. There was a positive correlation between T2 relaxation time variability and macrophage and T lymphocyte density in teeth with ICDAS score 2. In teeth with ICDAS score 3, a positive correlation between T2 relaxation times and T2 relaxation time variability and lymphocyte B density was found. CONCLUSION: The results of our study confirm the applicability of MRI in evaluation of the true condition of the pulp tissue. CLINICAL RELEVANCE: With the high correlation to histological validation, MRI method serves as a promising imaging implement in the field of general dentistry and endodontics.

Detection of Cavitated Proximal Carious Lesions in Permanent Teeth: A Visual and Radiographic Assessment.

Detection of proximal carious lesions involves the combination of clinical and radiographic methods, both with inherent difficulties. The present cross-sectional study is aimed at estimating the prevalence of cavitation in proximal carious lesions, based on a direct clinical assessment of previously detected radiographic lesions, in permanent molars and premolars. Proximal dental surfaces were radiographically evaluated using the ADA coding system and cavitation was determined through clinical visual examination of the surfaces after separation with elastomeric bands. One-hundred and twenty-six patients attending the dental clinics at the University of Talca were examined, comprising 508 proximal surfaces with radiographic codes ranging from E1 to D3. Two examiners were trained and calibrated for radiographic and clinical detection of proximal lesions. Most participants were females (61.9%). The age mean of participants was 28.7 (0.8) years old. A total of 22.2% of the examined surfaces were cavitated. Only few lesions coded as E1 (n = 4; 2.1%) and E2 (n = 9; 9.8%) were cavitated. Fifty D1 (35.5%) and 22 D2 (41.5%) lesions were cavitated after separation. Most lesions coded as D3 (n = 28; 84.8%) were cavitated. The multilevel binary regression model (p = 0.003) demonstrated that sex, age, jaw, tooth type, surface, and side were not associated with the likelihood of having proximal cavitation. Challenging conventional wisdom, most D1 and D2 lesions were not cavitated. Combining detection methods seems desirable to increase the accuracy in assessing approximal posterior lesions. The low proportion of cavitated lesions reinforces the idea of cautiously indicating invasive approaches for managing proximal carious lesions.

Effectiveness of Air Drying and Magnification Methods for Detecting Initial Caries on Occlusal Surfaces Using Three Different Diagnostic Aids.

Objective-The aim of this study was to assess the effect of magnification and air-drying on detection of carious lesion. Study Design-44 human extracted premolars were selected with sound occlusal surfaces without frank cavitation. The Diagnostic techniques used were Unaided visual examination, Magnifying Loupes (4.2×) and Stereomicroscope (10×, before and after air-drying) and then the teeth were sectioned bucco-lingually and both the surfaces were examined under Stereomicroscope (50×) to assess the presence or absence of carious lesion in the pit and fissures. The scores were compared to obtain Cohen's kappa coefficient (Reproducibility) and subjected to the Friedman Test and Paired t test. Sensitivity, specificity and positive predictive value used to assess accuracy. Results-On Statistical analysis, visual examination before and after air drying had highest specificity but lowest sensitivity compared to different diagnostic techniques. Magnifying loupes after air-drying had highest sensitivity and lowest specificity compared to other diagnostic techniques. Conclusion-Air drying combined with magnifying aids are cost-effective, reliable method for detection of early carious lesion. If used in pediatric clinical practice, any undesirable pain and discomfort to the patient due to invasive procedures and helps in employing preventive measures.

Comparison between rapid and mixed maxillary expansion through an assessment of arch changes on dental casts.

BACKGROUND: Aim of this retrospective observational study was to compare upper and lower dental changes in patients treated with Rapid Maxillary Expansion (RME) and Mixed Maxillary Expansion (MME), assessed by dental cast analysis. METHODS: Treatment groups consisted of 42 patients: the RME group (n = 21) consisted of 13 female and 8 male subjects with the mean age of 8.8 years ± 1.37 at T0 and 9.6 years ± 1.45 at T1; the MME group (n = 21) consisted of 12 female and 9 male patients with a mean age of 8.9 years ± 2.34 at T0 and 10.5 years ± 2.08 at T1. The upper and lower arch analysis was performed on four dental bilateral landmarks, on upper and lower casts; also upper and lower arch depths were measured. The groups were compared using independent sample t-test to estimate dental changes in upper and lower arches. RESULTS: Before expansion treatment (T0), the groups were similar for all examined variables (p>0.05). In both RME and MME group, significant increments in all the variables for maxillary and mandibular arch widths were observed after treatment. No significant differences in maxillary and mandibular arch depths were observed at the end of treatment in both groups. An evaluation of the changes after RME and MME (T1) showed statistically significant differences in mandibular arch depth (p<0.001) and maxillary intercanine widths (p<0.05). Differences in maxillary arch depth and arch width measurements were not significant. CONCLUSIONS: RME and MME can be considered two effective treatment options to improve transverse arch dimensions and gain space in the dental arches. A greater lower arch expansion was observed in the MME group, which might be attributed to the "lip bumper effects" observed in the MME protocol.

Assessment of a new infrared laser transillumination technology (808 nm) for the detection of occlusal caries-an in vitro study.

This study aimed to evaluate in vitro performance of near-infrared laser transillumination (NIR-LTI) for detecting early occlusal caries in permanent teeth and compare it with quantitative light-induced fluorescence (QLF), DIAGNOdent Pen (DDPen), and conventional radiography (CR). Ninety-four occlusal surfaces presenting International Caries Detection and Assessment System (ICDAS) scores ranging from 0 to 3 were selected. For the NIR-LTI examination, images were captured using a prototype, which consists of a laser beam (808 nm) and an infrared CCD camera. One occlusal site on each tooth was assessed twice by two examiners. The teeth were prepared histologically and assessed for the presence of early caries. The intraexaminer correlation showed no difference between the NIR-LTI, DDPen, and QLF analytical methods, but all these methods differed from CR. Interexaminer reproducibility was moderate for NIR-LTI, which showed sensitivity (0.68), specificity (0.85), accuracy (0.73), and area under the receiver-operating characteristic (ROC) curve (0.76) similar to those of the fluorescence method and different from those of the CR. In conclusion, the performance of NIR-LTI was comparable to that of DDPen and QLF and may therefore be considered a valid and reliable alternative for the diagnosis of incipient lesions on the occlusal surface of permanent teeth.

Is the value of oral health related to culture and environment, or function and aesthetics?

OBJECTIVE: To examine the disutility of tooth loss. It compared how people value their teeth in two countries which are culturally similar in order to explore the effect of culture on self-perceptions of oral health. BASIC RESEARCH DESIGN: Cross sectional study. PARTICIPANTS: Participants were recruited from subjects attending two hospitals in Turkey and in Iran. INTERVENTIONS: Nineteen descriptions of mouths with varying degrees and types of tooth loss were presented to the participants. They were shown mouth models of partially edentate dentitions and the teeth missing were explained in relation to the participants own mouth. The participants were specifically asked to consider the role their teeth played in function (chewing), communication (speech) and aesthetics (looks) along with "all the other things that make your mouth important". MAIN OUTCOME MEASURES: The participants were asked to indicate on a visual analogue scale how they would value the health of their mouth if they lost the tooth/teeth described and the resultant space was left unrestored. RESULTS: Overall 152 subjects participated, 78 in Turkey and 74 in Iran with 83 being female and 69 male. Their mean age was 29.5 years (SD 9.3), 62.5% had experienced tooth loss and 37.5% had complete (or completely restored) dentitions. Although there were no differences between the two countries in the degree of utility people attached to anterior teeth, Turkish participants attached significantly more disutility than Iranians to the loss of premolar and molar teeth (p < 0.003). CONCLUSION: Country of origin had an influence on the value placed on certain parts of the dentition and this effect is independent of the number of missing teeth, gender and age. This implies that attitudes to oral health are influenced by prevalent cultural attitudes more than by function.

An assessment of conventional and self-ligating brackets in Class I maxillary constriction patients.

OBJECTIVE: To evaluate two different treatment systems with regard to incisor position, transverse dimension changes in maxillary arch, changes in maxillary molar inclinations, clinical periodontal parameters, and pain intensity in patients with a Class I malocclusion. MATERIALS AND METHODS: Seventeen patients (with a mean age of 14.5 years) underwent orthodontic treatment with the Roth prescribed edgewise bracket systems after expanding the maxillary arch with a quad-helix appliance, and 16 patients (with a mean age of 14.8 years) underwent orthodontic treatment with the Damon 3MX bracket system. Each subject's lateral cephalometric and posteroanterior radiographs and dental casts were obtained at the beginning of the treatment and after debonding. In addition to these, the periodontal index and pain scores were taken. RESULTS: Cephalometric data showed that in both treatment systems, overjet value decreased and maxillary and mandibular incisors proclined. Posteroanterior measurements demonstrated a greater increase in the maxillary molar inclination in the Damon group. Significant increase of maxillary intercanine, interpremolar, and intermolar widths was shown in both systems. Periodontal index and pain score changes between different observation periods were the same. CONCLUSIONS: The conventional and Damon systems were found similar with regard to the incisor position, transverse dimension changes in maxillary arch, clinical periodontal parameters, and pain intensity. The only significant difference was that the Damon system inclined the maxillary molars more buccally than the conventional group.

Risk assessment of feline tooth resorption: a Portuguese clinical case control study.

Tooth resorption (TR) is one of the most common dental diseases in cats. Determination of risk factors has not yet been fully assessed and, to the best knowledge of the authors, this disease has never been studied in Portuguese cats. The objective of this case-control study was to determine type and distribution of TR lesions, evaluate risk factors, and establish relationships between variables in this disease. The study included data from 71 cats admitted for general anesthesia for various reasons. The cats were randomly selected. The inclusion criteria were availability of clinical history and owner permission. Cats with known oral disease were not excluded from the study. All cats received ultrasonic scaling and polishing of the teeth, a thorough oral examination, and full-mouth radiographs. A strong statistical relation was found between age and TR. The age group of 10 to 15-years showed an increased risk of 6.56 times for TR occurrence compared with the group 0 to 4-years of age. Presence of gingivitis in all index levels was related to an increased risk for TR. No relation was found between age or gingivitis index and lesion type. Mandibular third premolar and molar teeth were most commonly affected by TR, especially for type 1 lesions. Canine teeth were statistically more likely to have type 2 lesions. The trend for the canine teeth to be more affected with type 2 lesions needs further verification.

Components of patient satisfaction with a dental restorative visit: results from the Dental Practice-Based Research Network.

BACKGROUND: The authors conducted a study to identify components of patient satisfaction with restorative dental care and to test the hypothesis that certain dentist, patient and procedure factors are associated with patient satisfaction. METHODS: Practitioner-investigators (P-Is) from 197 practices in The Dental Practice-Based Research Network (DPBRN) recruited consecutively seen patients who had defective permanent-tooth restorations that were replaced or repaired. At the end of the treatment visit, P-Is asked each participant to complete a satisfaction survey and mail it directly to a DPBRN regional coordinator. RESULTS: Analysis of the results of 5,879 satisfaction surveys revealed three satisfaction components: interpersonal relationship-comfort factors, material choice-value factors and sensory-evaluative factors. Satisfaction was highest among patients who received care in a private practice model, whose restorations were repaired rather than replaced and whose restored teeth were not molars. CONCLUSION: These data suggest that a patient's judgments of a dentist's skills and quality of care are based on personal interactions with the dentist, the level of comfort the patient perceives while receiving care and any experience of posttreatment sensitivity in the treated tooth. These conclusions have direct implications for management of patient care before, during and after the procedure. PRACTICE IMPLICATIONS: By taking a patient-centered approach, dentists should seek to understand how patients evaluate and rate the service provided, thereby enabling themselves to focus on what each patient values most.

Assessment of the separation incidence of mtwo files used with preflaring: prospective clinical study.

INTRODUCTION: The Mtwo rotary system was designed to be used at full length without performing previous cervical enlargement or creating a manual glide path. However, to our knowledge, no study has investigated whether preflaring influences instrument fatigue. The purpose of this clinical study was thus to evaluate the incidence of separation of Mtwo instruments during the preparation of mandibular and maxillary molars and bicuspids that was preceded by cervical preflaring. METHODS: A total of 556 treatments were performed by 6 endodontists after calibration. Cervical enlargement and exploration with hand files were undertaken before using the rotary files. The canals were negotiated with small K-type hand files. Cervical and middle thirds were prepared with hand files and Gates-Glidden burs. Irrigation was performed with 2 mL of 2.5% NaOCl after each instrument. The working length was established, and the apical third was prepared with Flexofiles until a #15 file could reach the working length, establishing a glide path. The Mtwo instruments were used following manufacturer's recommendations and disposed of after being used in 5 teeth. Each file was examined under ×8 magnification after use. In cases of file deformation or separation, the entire file kit was no longer used, except when using the 10.04 file. Because of its high failure rate, which is well-established in the related literature, this instrument could be replaced at any time. RESULTS: Separation and deformation rates were 1.98% and 28.78%, respectively. Ten of the total separations observed occurred with the 10.04 file (90.01%) and one with the 15.05 file (9.09%). CONCLUSIONS: The use of Mtwo rotary instruments preceded by cervical preflaring with manual files and Gates-Glidden burs provides a low separation incidence.

Comparison of photographic and visual assessment of occlusal caries with histology as the reference standard.

BACKGROUND: The purpose of this study was to compare diagnostic performance for the detection of caries using photographs with an established visual examination method and histological sections as the reference standard. METHODS: 50 extracted permanent teeth were assessed for the presence of occlusal caries by 9 examiners using two methods; traditional visual examination developed by BASCD and photographs produced by an intra-oral camera. For both methods, diagnoses were made at "caries into dentine" level. The teeth were histologically sectioned and the diagnostic decisions using visual and photographic assessment were compared to the histological reference standard. Inter- and intra- examiner reliability for the methods was assessed and weighted kappa values were calculated. RESULTS: The visual examination method had a median sensitivity value of 65.6% and a median specificity value of 82.4%. The photographic assessments method had a median sensitivity of 81.3% and a median specificity of 82.4%. CONCLUSIONS: The photographic assessments method had a higher sensitivity for caries detection than the visual examination. The two methods had comparable specificities and good intra- and inter- examiner reliability.

Amalgam or composite resin? Factors influencing the choice of restorative material.

OBJECTIVES: This study aimed to investigate the patient and tooth factors associated with selection of restorative material in direct posterior restorations in young adults from a population-based birth cohort. METHODS: A representative sample (n=720) of all 5914 births occurring in Pelotas in 1982 were prospectively investigated, and posterior restorations were assessed in 2006, when the patients were 24 years old. Tooth-related variables (individual level) included restorative material (amalgam or composite), type of tooth, size of cavity, and estimated time in mouth. Data regarding demographic and socio-economic characteristics, oral health, and service utilization patterns during the life course were also assessed (contextual level). RESULTS: Logistic Regression Multilevel models showed that individuals who have accessed dental services by private insurance by age 15 [odds ratio (OR)=1.66 (0.93-2.95)] and who had a higher dental caries index at age 15 (high DMFT tertile) [OR 2.89 (1.59-5.27)] presented more amalgam restorations in the posterior teeth. From tooth-level variables, the frequency of amalgams decreases with increasing number of surfaces enrolled in the cavity preparation (p<0.001) and was almost 5 times greater in molars than in premolars. CONCLUSIONS: The present findings suggest that variables related to type of dental service, dental caries (higher DMFT index), and cavity characteristics (tooth type, size) determine the choice of dentists for restorative materials. Other individual characteristics such as demographic and socioeconomic status have not influenced this choice. CLINICAL SIGNIFICANCE: This is the first population-based study that assesses the determinant factors for the choice of dentists for composite or amalgam in posterior direct restorations, showing that, independently of socioeconomic and demographic characteristics, type of payment of dental services and clinical factors are associated with this choice.

Variations in caries diagnoses and treatment recommendations and their impacts on the costs of oral health care.

OBJECTIVE: To evaluate the reproducibility of caries detection and treatment planning among public health dentists and estimate the possible impact of their decisions on financial costs. RESEARCH DESIGN AND SETTINGS: Thirty nine dentists working in the public health service of Piracicaba, São Paulo, Brazil made a combined visual-radiographic caries examination of 40 occlusal surfaces of extracted permanent teeth mounted on two dental mannequins and proposed treatment plans for each tooth. Histological validation then evaluated the diagnoses validity and the suitability of the treatment plans. OUTCOME MEASURES: Inter-examiner agreement was calculated by Cohen's Kappa statistics. The sensitivity and specificity of caries detection and treatment decision were calculated. The costs of dental treatment plans for public health system were calculated from a Brazilian public health service fee scale. RESULTS: Inter-examiner agreement for caries detection was moderate (kappa = 0.42) while for treatment decisions it was fair (kappa = 0.29). The sensitivity and specificity were 0.69 and 0.65 for caries detection and 0.56 and 0.65 for treatment decision respectively. Dentists overestimated the presence and depth of carious lesions and there was a tendency to treat enamel lesions using invasive therapeutic procedures. Mean treatment cost across the two cases was 32US$ (range 9-65) while the histologically validated cost was 23US$. CONCLUSION: The variability in caries detection and treatment decision negatively affected the cost of the dental treatment.

Factors associated with self-assessed masticatory ability among community-dwelling elderly Japanese.

UNLABELLED: Self-assessed masticatory ability has been shown to be significantly related to general health among elderly persons. OBJECTIVE: To identify oral factors associated with the self-assessed masticatory ability. BASIC RESEARCH DESIGN: Cross-sectional study. PARTICIPANTS: A total of 736 community-dwelling elderly persons. MAIN OUTCOME MEASURES: Data on background factors and the self-assessed masticatory ability were collected by questionnaire. An intraoral examination examined the pattern of posterior occluding pairs of natural teeth (POPs), the WHO Community Periodontal Index of Treatment Needs (CPI) and denture-related factors such as use of dentures, pain when using dentures and stability and retention of dentures. Chi-squared tests examined the relationships between the self-assessed masticatory ability and the background factors and oral conditions. Ordinal regression models were constructed with the self-assessed masticatory ability as the dependent variable and oral conditions as the principal independent variables, to adjust for the potential confounding variables. RESULTS: Self-assessed impairment of masticatory ability was associated with lost POPs (p < 0.001) and CPI (p = 0.012). In the participants with lost POPs, self-assessed impairment of masticatory ability was associated with not using dentures and pain when using dentures (p < 0.001). In the totally edentulous subjects, impairment of masticatory ability was not associated with stability and retention of dentures (p = 0.070). CONCLUSIONS: Factors affecting self-assessed masticatory ability include the pattern of POPs, periodontal status, denture use and pain when using dentures.

Assessment of laminate technique using glass ionomer and resin composite for restoration of root filled teeth.

OBJECTIVE: To evaluate the open laminate technique using glass ionomer cements (GIC) in association with a low shrink composite for restoring root filled premolars. METHODS: Extensive MOD cavities plus endodontic access and root filling were performed in intact extracted maxillary premolars. Three restoration types were evaluated: (1) resin composite alone; (2) resin-modified GIC (RM-GIC) open laminate plus resin composite; (3) conventional GIC open laminate plus resin composite (n=8 for all groups and tests). Three tests were conducted to assess restorations: (A) inward cusp deflection during light curing, using DCDTs; (B) fracture strength using a ramped oblique load at 45° to the long axis in a servohydraulic testing machine in comparison with intact and unrestored teeth; (C) proximal marginal leakage using methylene blue dye and the effect of thermocycling. Data were analysed using 1-way ANOVA for cuspal deflection and fracture strength and Fisher's exact test for leakage. RESULTS: Laminate restorations resulted in significantly less cuspal deflection compared with resin composite (4.2±1.2 µm for RM-GIC and 5.1±2.3 µm for conventional GIC vs. 12.2±2.6 µm for composite, P<0.001). Fracture strength was not significantly different among all groups. Failure with all restorations was predominantly adhesive at the tooth-restoration interface. The two laminate groups showed significantly better marginal seal than composite alone, but sealing ability of conventional GIC deteriorated after thermocycling. CONCLUSIONS: Laminate restoration of root filled teeth had beneficial effects in terms of reducing cuspal deflection and marginal seal, with acceptable fracture strength.

Caries management by risk assessment.

New York University College of Dentistry utilizes a protocol for caries management by risk assessment. It includes guidelines for determining several indicators and factors that are used to identify whether a patient is at high, moderate or low risk for dental caries. This case report presents an assessment of a patient with high caries risk and the system used to treat the disease process and lower the patient's risk for future lesions.

A comparison of methods using optical coherence tomography to detect demineralized regions in teeth.

Optical coherence tomography (OCT) is a three- dimensional optical imaging technique that can be used to identify areas of early caries formation in dental enamel. The OCT signal at 850 nm back-reflected from sound enamel is attenuated stronger than the signal back-reflected from demineralized regions. To quantify this observation, the OCT signal as a function of depth into the enamel (also known as the A-scan intensity), the histogram of the A-scan intensities and three summary parameters derived from the A-scan are defined and their diagnostic potential compared. A total of 754 OCT A-scans were analyzed. The three summary parameters derived from the A-scans, the OCT attenuation coefficient as well as the mean and standard deviation of the lognormal fit to the histogram of the A-scan ensemble show statistically significant differences (p < 0.01) when comparing parameters from sound enamel and caries. Furthermore, these parameters only show a modest correlation. Based on the area under the curve (AUC) of the receiver operating characteristics (ROC) plot, the OCT attenuation coefficient shows higher discriminatory capacity (AUC = 0.98) compared to the parameters derived from the lognormal fit to the histogram of the A-scan. However, direct analysis of the A-scans or the histogram of A-scan intensities using linear support vector machine classification shows diagnostic discrimination (AUC = 0.96) comparable to that achieved using the attenuation coefficient. These findings suggest that either direct analysis of the A-scan, its intensity histogram or the attenuation coefficient derived from the descending slope of the OCT A-scan have high capacity to discriminate between regions of caries and sound enamel.

Reliability of Logicon caries detector in the detection and depth assessment of dental caries: an in-vitro study.

BACKGROUND: Digital radiography has so far not resulted in improved rates of proximal caries detection. Historically, automated caries detection tools have been largely academic. Opinions regarding the performance of the only such commercially available tool, viz., Logicon caries Detector (LCD) have been equivocal. This study was conducted to evaluate the reliability of LCD in the detection and depth assessment of proximal caries. MATERIALS AND METHODS: Digital images were obtained of 100 proximal tooth surfaces using the Kodak RVG 5000 sensor and analyzed by three observers. The images were then analyzed by the principal investigator using the LCD software. The teeth were then sectioned and magnified photographic images were obtained which were taken as the gold standard. All the grades were entered in proformas and the data were statistically analyzed using the chi-square test. Five parameters of reliability were calculated. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of LCD for the grade No caries were 33, 96, 73, 82, and 81%, respectively; for the grade Enamel caries were 5, 97, 33, 80, and 79%, respectively; and for the grade Dentin caries were 100, 96, 50, 100, and 96%, respectively. CONCLUSIONS: In conclusion, LCD appears to be more reliable in ruling out (both enamel and dentin) caries than in detecting caries.

Practitioner, patient and carious lesion characteristics associated with type of restorative material: findings from The Dental Practice-Based Research Network.

BACKGROUND: The authors conducted a study to identify factors associated with the materials that dentists in The Dental Practice-Based Research Network (DPBRN) use when placing the first restoration on permanent posterior tooth surfaces. METHODS: A total of 182 DPBRN practitioner-investigators provided data regarding 5,599 posterior teeth with caries. Practitioner-investigators completed an enrollment questionnaire that included the dentist's age, sex, practice workload, practice type and number of years since graduation. When patients who had provided informed consent to participate in the investigation sought treatment for a previously unrestored carious surface, the practitioner-investigator recorded patient and tooth characteristics. RESULTS: Practitioner-investigators used amalgam more often than they used direct resin-based composite (RBC) for posterior carious lesions. Practitioner and practice characteristics (years since graduation and type of practice); patient characteristics (sex, race, age and dental insurance status); and lesion characteristics (tooth location and surface, preoperative and postoperative lesion depth) were associated with the type of restorative material used. CONCLUSIONS: Several practitioner and practice, patient and lesion characteristics were associated significantly with use of amalgam and RBC: geographical region, years since dentist's graduation, patient's dental insurance status, tooth location and surface, and preoperative and postoperative lesion depth. CLINICAL IMPLICATIONS: Despite advances in esthetic dentistry, U.S. dentists still are placing amalgam on posterior teeth with carious lesions. Amalgam was used more often than RBC in older patients, who may have had deeper carious lesions.

The influence of cone-beam computed tomography and periapical radiographic evaluation on the assessment of periapical bone destruction in dog's teeth.

OBJECTIVE: The aim of this study was to determine the influence of periapical radiographs, cone beam computed tomography (CBCT) sections, and cone beam volumetric data on the determination of periapical bone destruction in endodontically treated distal root canals of premolar canine teeth. Nontreated mesial roots were used as controls. STUDY DESIGN: Enterococcus faecalis strain (ATCC 29212) was inoculated into 30 root canals of 2 mongrel dogs to induce apical periodontitis. After 60 days, the root canals of the distal roots of the 11 mandibular and 4 maxillary premolars were endodontically treated (n = 15). The mesial root canals were used as controls (no treatment). The bone destruction was evaluated after 6 months by 5 evaluators using periapical radiographs and by CBCT (coronal and sagittal sections). After the experimental period, the area of the lesions in periapical radiographs and CBCT sections were measured in mm(2) using the ImageTool software. A single evaluator measured the volumetric data using the OsiriX software. The comparison between the diagnosis methods in treated root canals and controls was performed using parametric and nonparametric criteria. The Pearson correlation coefficient was computed between radiographic values and CBCT volumetric data in treated root canals and controls. RESULTS: The results showed the presence of chronic apical periodontitis in every inoculated tooth. After 6 months, periapical radiographs, coronal CBCT sections, and volumetric data showed lower bone destruction in endodontically treated teeth in comparison with the control group (P < .05). The 5 evaluators found no differences between the apical periodontitis area of treated teeth and controls when CBCT sagittal sections were used (P > .05). No correlation was found between x-ray and CBCT volumetric values in treated root canals. CONCLUSIONS: Although selected CBCT sagittal sections showed similar values of bone destruction in endodontically and nontreated root canals, volumetric CBCT data showed that periapical lesions of endodontically treated root canals had half of the volume of periapical lesions in nontreated root canals. No relationship could be found between the periapical values of bone destruction and volumetric data found in CBCT of treated rood canals.