Comparative efficacy of materials used in patients undergoing pulpotomy or direct pulp capping in carious teeth: A systematic review and meta-analysis

OBJECTIVES

Different materials have been used for capping the pulp after exposure during caries removal in permanent teeth. The purpose of this study was to collate and analyze all pertinent evidence from randomized controlled trials (RCTs) on different materials used in patients undergoing pulpotomy or direct pulp capping in carious teeth.

MATERIALS AND METHODS

Trials comparing two or more capping agents used for direct pulp capping (DPC) or pulpotomy were considered eligible. An electronic search of four databases and two clinical trial registries was carried out up to February 28, 2021 using a search strategy properly adapted to the PICO framework. Screening, data extraction, and risk of bias (RoB) assessment of primary studies were performed in duplicate and independently. The primary outcome was clinical and radiological success; secondary outcomes included continued root formation, tooth discoloration, and dentin bridge formation.

RESULTS

21 RCTs were included in the study. The RoB assessment indicated a moderate risk among the studies. Due to significant clinical and statistical heterogeneity among the studies, performing network meta-analysis (NMA) was not possible. An ad hoc subgroup analysis revealed strong evidence of a higher success of DPC with Mineral Trioxide Aggregate (MTA) compared to calcium hydroxide (CH) (odds ratio [OR] = 3.10, 95% confidence interval [CI]: 1.66-5.79). MTA performed better than CH in pulp capping (both DPC and pulpotomy) of mature compared to immature teeth (OR = 3.34, 95% CI: 1.81-6.17). The GRADE assessment revealed moderate strength of evidence for DPC and mature teeth, and low to very low strength of evidence for the remaining subgroups.

CONCLUSIONS

Considerable clinical and statistical heterogeneity among the trials did not allow NMA. The ad hoc subgroup analysis indicated that the clinical and radiographic success of MTA was higher than that of CH but only in mature teeth and DPC cases where the strength of evidence was moderate. PROSPERO Registration: number CRD42020127239.

The effect of orthodontic treatment on smile attractiveness: a systematic review

BACKGROUND

Smile attractiveness is a primary factor for patients to seek orthodontic treatment, however, there is yet no systematic evaluation of this topic in the literature.

OBJECTIVES

To assess the current evidence on the effect of orthodontic treatment on smile attractiveness.

SEARCH METHODS

Seven electronic databases (MEDLINE, Cochrane Library, Virtual Health Library, SCOPUS, Web of Science, Google Scholar and Embase) were searched on 14 September 2022.

SELECTION CRITERIA

Studies evaluating smile attractiveness before and after orthodontic treatment or only after completion of orthodontic treatment.

DATA COLLECTION AND ANALYSIS

Extracted data included study design and setting, sample size and demographics, malocclusion type, treatment modality and method for outcome assessment. Risk of bias was assessed with the ROBINS-I tool for non-randomised studies. Random-effects meta-analyses of mean differences and their 95% confidence intervals (CIs) were planned a priori.

METHODS

After elimination of duplicate studies, data extraction and risk of bias assessment according to the Cochrane guidelines, an evaluation of the overall evidence was performed. The included studies were evaluated based on the characteristics of their study and control groups and based on their main research question. Also, all outcome measures were standardized into a common assessment scale (0-100), in order to obtain more easily interpretable results.

RESULTS

Ten studies were included in this review, nine of which were assessed as being at serious risk of bias and one at moderate risk of bias. The large heterogeneity between the included studies did not allow for a meta-analysis. Orthodontic treatment has a moderately positive effect on smile attractiveness. When compared to no treatment, orthodontic treatment with premolar extractions improves smile attractiveness by 22%. Also, surgical correction of Class III cases increases smile attractiveness by 7.5% more than camouflage treatment. No other significant differences were shown between different types of treatment.

CONCLUSION

Based on the available data, orthodontic treatment seems to moderately improve the attractiveness of the smile. There is significant bias in the current literature assessing the effect of orthodontics on smile attractiveness; therefore, the results cannot be accepted with certainty.

Early Optimistic Effect in Periodontology and Implant Dentistry Trials

Differences in effect estimates between early primary trials included in a meta-analysis and the pooled estimate of meta-analysis might indicate potential novelty bias. The objective of this study was to assess the presence of novelty bias in a sample of studies published in periodontology and implant dentistry. On August 7, 2020, we searched the PubMed database for meta-analyses of clinical studies published between August 2015 and August 2020. Meta-analyses with at least 4 primary studies were selected for assessment. We fitted logistic regression models using trial characteristics as predictors to assess the association between these characteristics and 1) the odds of the first trial's estimate to be included in the meta-analysis confidence interval (CI) and 2) the odds of overlap between the first trial's CI and the meta-analysis prediction interval (PI). Ninety-two meta-analyses provided data for assessment. In absolute values, 70% of the meta-analyses have a pooled estimate smaller than the corresponding estimate of the first trial, although there was overlap of the CI of estimates from the first trial and the meta-analysis in 87% of the cases. This is probably due to the small number of trials in most meta-analyses and the subsequently large uncertainty associated with the pooled effect estimate. As the number of trials in the meta-analysis increased, the odds of the treatment effect estimate of the first trial to be included in the meta-analysis CI decreased by 15% for every additional trial (odds ratio, 0.85; 95% CI, 0.73 to 0.96). Meta-analytic effect estimates appear to be more conservative than those from the first trial in the meta-analysis. Our findings show evidence of novelty bias in periodontology and implant dentistry; therefore, clinicians should be aware of the risk of making decisions based on the information reported in new trials because of the risk of exaggerated estimates in these trials.

Do reporting guidelines have an impact? Empirical assessment of changes in reporting before and after the PRISMA extension statement for network meta-analysis

BACKGROUND

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension statement for network meta-analysis (NMA) published in 2015 promotes comprehensive reporting in published systematic reviews with NMA. PRISMA-NMA includes 32 items: 27 core items as indicated in the 2009 PRISMA Statement and five items specific to the reporting of NMAs. Although NMA reporting is improving, it is unclear whether PRISMA-NMA has accelerated this improvement. We aimed to investigate the impact of PRISMA-NMA and highlight key items that require attention and improvement.

METHODS

We updated our previous collection of NMAs with articles published between April 2015 and July 2018. We assessed the completeness of reporting for each NMA, including main manuscript and online supplements, using the PRISMA-NMA checklist. The PRISMA-NMA checklist originally includes 32 total items (i.e. a 32-point scale original PRISMA-NMA score). We also prepared a modified version of the PRISMA-NMA checklist with 49 items to evaluate separately at a more granular level all multiple-content items (i.e. a 49-point scale modified PRISMA-NMA score). We compared average reporting scores of articles published until and after 2015.

RESULTS

In the 1144 included NMAs the mean modified PRISMA-NMA score was 32.1 (95% CI 31.8-32.4) of a possible 49-excellence-score. For 1-year increase, the mean modified score increased by 0.96 (95% CI 0.32 to 1.59) for 389 NMAs published until 2015 and by 0.53 (95% CI 0.02 to 1.04) for 755 NMAs published after 2015. The mean modified PRISMA-NMA score for NMAs published after 2015 was higher by 0.81 (95% CI 0.23 to 1.39) compared to before 2015 when adjusting for journal impact factor, type of review, funding, and treatment category. Description of summary effect sizes to be used, presentation of individual study data, sources of funding for the systematic review, and role of funders dropped in frequency after 2015 by 6-16%.

CONCLUSIONS

NMAs published after 2015 more frequently reported the five items associated with NMA compared to those published until 2015. However, improvement in reporting after 2015 is compatible with that observed on a yearly basis until 2015, and hence, it could not be attributed solely to the publication of the PRISMA-NMA.

Dental Research Waste in Design, Analysis, and Reporting: A Scoping Review

Research waste is highly prevalent across biomedical investigations. We aimed to assess the evidence on the extent of research waste in dental research. We performed a scoping review of empirical evaluations of dental studies assessing the prevalence and impact of limitations in design, conduct, analysis, and reporting of research. PubMed was searched using specific terms to retrieve studies dealing with design, conduct, analysis, and reporting of studies in dentistry, with no year or language restrictions. Of the 1,807 publications identified from the search and from manual searches, 71 were included in this review. The topic and article selection was based on the expert opinion of the authors. The existing evidence suggests that, although there are improvements over time, substantial deficiencies in all areas (design, conduct, analysis, reporting) were prevalent in dental research publications. Waste in research is a multifaceted problem without a simple solution. However, an appreciation of optimal research design and execution is a prerequisite and should be underpinned by policies that include appropriate training in research methods and properly aligned incentives.

Quantitative evaluation of the progressive wear of powered interproximal reduction systems after repeated use : An in vitro study

PURPOSE

To evaluate the residual surface roughness of 5 common diamond-coated interproximal reduction (IPR) systems after consecutive in vitro applications in relation to system, diamond grain size, and instrument thickness.

METHODS

IPR was performed on 80 extracted human incisors using motor-driven strips and discs under predefined conditions. The IPR auxiliaries were applied at 5 consecutive sessions of 20 s on intact interproximal surfaces, and the surface profile (R_a, R_z, R_max) was analyzed at baseline and after each session with an optical profilometer.

RESULTS

No overall significant difference in the roughness values was found between systems (P = 0.07 for R_a, P = 0.33 for R_z, and P = 0.48 for R_max). There was a significant average decrease of R_a, R_z, and R_max for all systems for every unit increase in time by -0.171 μm (P < 0.001), -3.297 (P ≤ 0.001), and -2.788 μm (P = 0.001), respectively. R_a, R_z, and R_max values increased significantly, i.e., by 0.194 μm (P = 0.003), 5.890 μm (P = 0.001), and 5.319 μm (P = 0.010) as instrument thickness increased by one unit. No significant reductions in R_a, R_z, and R_max were observed across grain sizes (-0.008 μm [P > 0.05], -0.244 μm [P > 0.05], and -0.179 μm [P > 0.05], respectively). There was no evidence of interaction between system and time as the P values for R_a, R_z, and R_max were 0.88, 0.51, and 0.70, respectively.

CONCLUSIONS

All IPR materials presented significant gradual decrease of surface roughness after repeated applications. There were no significant roughness changes among auxiliaries of different grain sizes. Thinner auxiliaries showed significantly more roughness reduction, possibly requiring more frequent replacement than thick auxiliaries in clinical practice.

Quality assessment of clinical practice guidelines used in oral and maxillofacial surgery

An assessment of the quality of oral and maxillofacial surgery clinical practice guidelines is lacking. The aim of this investigation was to assess the quality of guidelines using the RIGHT (Reporting Items for practice Guidelines in HealThcare) checklist. The primary outcome was to assess the score (quality) of guidelines based on the RIGHT checklist and to identify predictors (region, type, single or multi-centre, and speciality/non-speciality) influencing the quality score. In this review, following a search of electronic databases and national society websites, a total of 25 guidelines were independently assessed by two assessors against the 22-item RIGHT checklist. Inter-assessor reliability was assessed. Deficiencies in the reporting of items relating to limitations, funding, declaration and management of interests, healthcare questions, and quality assurance were evident. The median overall score for the guidelines was 28 (range 14-66). Guidelines produced by multiple centres (β=57.15, 95% confidence interval -26.62 to 87.68, P= 0.001, multivariate analysis) and non-speciality societies (β=20, 95% confidence interval -0.03 to 40.03, P=0.05, univariate analysis) tended to have higher quality scores. Overall, the quality of clinical practice guidelines used in oral and maxillofacial surgery was deemed suboptimal. If clinical practice guidelines are to be used in making treatment decisions for patients, clinicians should be aware of their possible limitations.

Information for oral and maxillofacial patients: can it be improved?

The aim and objective of this study was to evaluate the quality and readability of leaflet and online Oral and Maxillofacial Surgery patient information leaflets (PILs). The quality, readability and grade level of each PIL was assessed using the DISCERN, Flesch Reading Ease and Flesh-Kincaid Grade Level instruments respectively. In total, 140 patient information leaflets were assessed. For both leaflet and online PILs, many items of the DISCERN instrument were deemed of low quality and poorly reported. The median overall quality score was 30.2. Variation in the quality and readability scores between leaflet and online PILs and those produced by various societies was evident. Overall, PILs were deemed to be of moderate quality. Online PILs were of lower quality, more difficult to read and aimed at a higher reading age level.

CONSORT 2010 statement: extension checklist for reporting within person randomised trials

Evidence shows that the quality of reporting of randomised controlled trials (RCTs) is not optimal. The lack of transparent reporting impedes readers from judging the reliability and validity of trial findings and researchers from extracting information for systematic reviews and results in research waste. The Consolidated Standards of Reporting Trials (CONSORT) statement was developed to improve the reporting of RCTs. Within person trials are used for conditions that can affect two or more body sites, and are a useful and efficient tool because the comparisons between interventions are within people. Such trials are most commonly conducted in ophthalmology, dentistry, and dermatology. The reporting of within person trials has, however, been variable and incomplete, hindering their use in clinical decision making and by future researchers. This document presents the CONSORT extension to within person trials. It aims to facilitate the reporting of these trials. It extends 16 items of the CONSORT 2010 checklist and introduces a modified flowchart and baseline table to enhance transparency. Examples of good reporting and evidence based rationale for CONSORT within person checklist items are provided.

Collaboration in orthodontic clinical trials: prevalence and association with sample size and funding

BACKGROUND

To assess patterns of research collaboration in orthodontics and possible relationships with sample size and funding status.

METHODS

Orthodontic randomised and non-randomised controlled clinical trials published between 2013 and 2017 were identified through electronic searching. The nature of collaboration, author institutions, study setting, sample size, and funding status were assessed. Linear and logistic regression analyses were applied.

RESULTS

Of 1153 studies, 217 met the selection criteria. The majority of studies were authored by university academics (86%), were conducted in a single centre (71.9%) and in at least one university hospital (68.2%). The number of practice-based trials (10.1%), as well as the involvement of specialist practitioners (5.2%) in co-authorship, was limited. Multi-centred studies within a single country were associated with a significantly larger sample size compared to single-centred trials (P = 0.00; 95% confidence interval [CI] 33.59, 106.93). However, authorship collaboration either nationally (odds ratio [OR] 2.37; 95% CI 0.85, 6.57) or internationally across different continents (OR 5.54; 95% CI 0.62, 49.52) did not translate into increased funding.

CONCLUSIONS

Most orthodontic studies were undertaken in university hospital settings within a single country. Collaboration is common in orthodontics but involvement of practice settings remains limited, suggesting a need for stimulation of practice-based research and research partnerships.

A cross-sectional analysis of Wits and Riedel in adults with skeletal III malocclusion: How informative are they?

OBJECTIVES

To compare the relationship between Riedel and Wits appraisal in skeletal III malocclusions and to assess the effect of variation in the vertical skeletal measurements.

SETTING AND SAMPLE POPULATION

One-hundred and twenty consecutive subjects with Class III malocclusions attending orthognathic clinics were analysed.

MATERIALS AND METHODS

Lateral cephalograms were hand-traced under standardized conditions. Cephalometric measurements included Riedel analysis, Wits appraisal, A point/B point to Frankfurt plane (AF-BF) and vertical measurements.

RESULTS

The mean ANB and Wits values were -3.22° and -11.39 mm, respectively. A positive correlation was found between ANB and Wits overall (r = -.49; P < .001). However, there was poor agreement between both Wits (r = .087) and Riedel (r = .089) with AF-BF (P > .05). A negative correlation existed between Wits and LAFH% (r = -.64, P-value < .001); however, no relationship was observed between ANB and LAFH% (P > .05) based on linear regression analysis.

CONCLUSIONS

There is a positive relationship between ANB and Wits; however, neither correlated well with a purer antero-posterior assessment (AF-BF). Furthermore, variations in the vertical skeletal measurements affect the strength of agreement. Caution is advised in the interpretation of antero-posterior analysis especially in the presence of vertical discrepancy.

A prospective cohort study assessing the appearance of retrieved aesthetic orthodontic archwires

OBJECTIVES

To investigate the appearance of three esthetic nickel titanium (NiTi) wires after 6 weeks of intra-oral cycling and to determine the association between objective and subjective measures of esthetics.

SETTING AND SAMPLE POPULATION

A prospective cohort study was undertaken involving participants undergoing upper fixed orthodontic appliance treatment with ceramic brackets.

MATERIALS AND METHODS

Fifty participants were assigned to one of three groups of NiTi esthetic wires (American Orthodontics Ever White™, Forestadent Biocosmetic™ and GAC High Aesthetic™), with wires retrieved after 6 weeks in situ. Participants completed a bespoke questionnaire exploring perceptions of wire esthetics. Objective measurement of coating loss was undertaken using a custom arch wire jig.

RESULTS

American Orthodontics Ever White™ had the greatest mean coating loss (50.7%) followed by Forestadent Biocosmetic™ (6%), with GAC High Aesthetic TM undergoing minimal loss (0.07%) (P < .001). The majority of coating loss with the American Orthodontics Ever White™ wires arose in the anterior region while Forestadent Biocosmetic™ wires and GAC High Aesthetic™ wires exhibited coating loss posteriorly (P < .001). These findings were reflected in the subjective assessment with a negative correlation found between coating loss and final Visual Analogue Scale scores (P < .001).

CONCLUSIONS

Considerable esthetic variation between arch wires following 6 weeks of intraoral cycling was identified in this prospective cohort study. Intraoral cycling has a negative impact on participant perception of arch wire esthetics, and objective and subjective assessment of wire esthetics appears to be consistent.

Statins in nonsurgical and surgical periodontal therapy. A systematic review and meta-analysis of preclinical in vivo trials

The cholesterol-lowering drugs, statins, possess anti-inflammatory, antimicrobial and pro-osteogenic properties, and thus have been tested as an adjunct to periodontal treatment. The present systematic review aimed to answer the following focused research question: What is the effect of local and/or systemic statin use on periodontal tissues in preclinical in vivo studies of experimentally induced periodontitis (EIP) and/or acute/chronified periodontal defect (ACP) models? A literature search (of Medline/PubMed, Embase/Ovid, CENTRAL/Ovid) using the following main eligibility criteria was performed: (i) English or German language; (ii) controlled preclinical in vivo trials; (iii) local and/or systemic statin use in EIP and/or ACP models; and (iv) quantitative evaluation of periodontal tissues (i.e., alveolar bone level/amount, attachment level, cementum formation, periodontal ligament formation). Sixteen studies in EIP models and 7 studies in ACP models evaluated simvastatin, atorvastatin or rosuvastatin. Thirteen of the EIP (81%) and 2 of the ACP (29%) studies presented significantly better results in terms of alveolar bone level/amount in favor of statins. Meta-analysis based on 14 EIP trials confirmed a significant benefit of local and systemic statin use (P < .001) in terms of alveolar bone level/amount; meta-regression revealed that statin type exhibited a significant effect (P = .014) in favor of atorvastatin. Three studies reported a significantly higher periodontal attachment level in favor of statin use (P < .001). Complete periodontal regeneration was never observed; furthermore, statins did not exert any apparent effect on cementum formation. Neither local nor systemic use of statins resulted in severe adverse effects. Statin use in periodontal indications has a positive effect on periodontal tissue parameters, supporting the positive results already observed in clinical trials. Nevertheless, not all statins available have been tested so far, and further research is needed to identify the maximum effective concentration/dose and optimal carrier.

Histochemical changes of occlusal surface enamel of permanent teeth, where dental caries is questionable vs sound enamel surfaces

AIM

This in vitro study was to classify questionable for caries occlusal surfaces (QCOS) of permanent teeth according to ICDAS codes 1, 2, and 3 and to compare them in terms of enamel mineral composition with the areas of sound tissue of the same tooth.

METHODS

Partially impacted human molars (60) extracted for therapeutic reasons with QCOS were used in the study, photographed via a polarised light microscope and classified according to the ICDAS II (into codes 1, 2, or 3). The crowns were embedded in clear self-cured acrylic resin and longitudinally sectioned at the levels of the characterised lesions and studied by SEM/EDX, to assess enamel mineral composition of the QCOS. Univariate and multivariate random effect regressions were used for Ca (wt%), P (wt%), and Ca/P (wt%).

RESULTS

The EDX analysis indicated changes in the Ca and P contents that were more prominent in ICDAS-II code 3 lesions compared to codes 1 and 2 lesions. In these lesions, Ca (wt%) and P (wt%) concentrations were significantly decreased (p = 0.01) in comparison with sound areas. Ca and P (wt%) contents were significantly lower (p = 0.02 and p = 0.01 respectively) for code 3 areas in comparison with codes 1 and 2 areas. Significantly higher (p = 0.01) Ca (wt%) and P (wt%) contents were found on sound areas compared to the lesion areas.

CONCLUSIONS

The enamel of occlusal surfaces of permanent teeth with ICDAS 1, 2, and 3 lesions was found to have different Ca/P compositions, necessitating further investigation on whether these altered surfaces might behave differently on etching preparation before fissure sealant placement, compared to sound surfaces.

Detection of TMPRSS2-ERG fusion gene in benign prostatic hyperplasia

The Ets-related gene fusions are among the most common molecular alterations in prostate cancer (PCa) and are detected in more than 50 % of PCas. Transmembrane protease serine 2 and Ets-related gene fusion (TMPRSS2-ERG) is the most frequently identified chimeric gene and has been associated with undifferentiated and invasive phenotypes. TMPRSS2-ERG has also been detected in prostate intraepithelial neoplasia (PIN) lesions and more rarely in benign prostatic hyperplasia (BPH) regions mainly in PCa-bearing glands. The possibility that the fusion TMPRSS2-ERG may be present in BPH samples in the absence of apparent PCa was addressed. Out of 115 BPH samples, three were found positive employing RT-PCR. The presence of the fusion gene was confirmed by FISH for these samples, and an additional four samples were found to carry the TMPRSS2-ERG fusion out of 43 tested by the later approach. The presence of the TMPRSS2-ERG fusion did not result in altered expression of 12 putative downstream targets. These findings indicate that TMPRSS2-ERG may or may not lead to PCa development.

Cytogenetic analysis of a low-grade secondary peripheral chondrosarcoma arising in synovial chondromatosis

Secondary chondrosarcoma is a malignant chondroid tumor arising in a benign precursor. Synovial chondromatosis is a benign chondroid lesion that rarely transforms to chondrosarcoma. We present the case of a 54-year-old male with the diagnosis of low-grade secondary peripheral chondrosarcoma developed in the context of synovial chondromatosis. Cytogenetics revealed a novel aberration t(1;14)(q23.1~24;q24.1~3). Multicolor banding (mBAND) analysis described the chromosomal regions involved in this translocation with a higher detail. Diagnosis of such borderline lesions is very difficult and cytogenetics is helpful in characterizing these tumors.

Clonal chromosome-aberrations in fibrocystic breast disease-associated with increased risk of cancer

Short-term cultures of 29 samples of fibrocystic breast disease were cytogenetically analyzed. Clonal chromosome aberrations were found in six specimens, whereas the remaining 23 had a normal karyotype. Three of the abnormal samples displayed karyotypic anomalies previously associated with breast cancer, i.e., gain of Iq, trisomy 18 and cytogenetic multiclonality. Furthermore, all cytogenetically aberrant specimens had either proliferative disease without atypia or atypical hyperplasia, features of fibrocystic disease considered risk factors for subsequent breast cancer development. The cytogenetic similarities between breast carcinomas and proliferative fibrocystic breast disease add further support for classifying certain types of fibrocystic disease as a premalignant condition. Whether cytogenetically abnormal fibrocystic lesions are the ones that subsequently progress to cancer remains to be elucidated.

12q amplification defines a subtype of extraskeletal osteosarcoma with good prognosis that is the soft tissue homologue of parosteal osteosarcoma

Extraskeletal osteosarcomas are rare tumors with neoplastic cells synthesizing bone, usually associated with poor prognosis. We present the case of a 40-year-old man with an extraskeletal osteosarcoma that was treated by surgery and adjuvant radiotherapy. Thirteen years after the diagnosis, he remains disease-free, without any recurrences or metastases. Histopathological analysis favored the diagnosis of chondroblastic extraskeletal osteosarcoma grade II. G-banding, comparative genomic hybridization (CGH), and real-time PCR for the MDM2 and CDK4 genes were performed to describe the genetic profile of this tumor and revealed aberrations that are common findings of parosteal osteosarcomas. Ring chromosomes, giant marker chromosomes, and a telomeric association were found with G-banding. CGH revealed that 12q was amplified in the ring and giant markers identified by G-banding. Real-time PCR for MDM2 and CDK4 confirmed the amplification of these genes located in 12q. Our findings suggest that a variant of extraskeletal osteosarcoma, which is genotypically similar to parosteal osteosarcoma, exists and is associated with good prognosis.

Similar cytogenetic findings in two synchronous secondary peripheral chondrosarcomas in a patient with multiple osteochondromas

Secondary peripheral chondrosarcoma is a malignant chondroid tumor arising in a benign precursor, either an osteochondroma or an enchondroma. Multiple osteochondromas syndrome (MO) is an autosomal dominant skeletal disorder associated with bony growths in the form of osteochondromas that occasionally undergo malignant transformation to secondary peripheral chondrosarcomas. We describe the genetic examination of three secondary peripheral chondrosarcomas that had arisen synchronously from osteochondromas in a patient with MO by chromosome banding, high resolution chromosomal comparative genomic hybridization, and mutation analysis of the EXT1 and EXT2 genes. In two of the tumors (the third was not genetically informative), very similar chromosome abnormalities were found, indicating that they must somehow be part of the same neoplastic process in spite of being anatomically distinct.

Forces and moments on posterior teeth generated by incisor intrusion biomechanics

OBJECTIVES

To comparatively evaluate the extrusive forces and torquing moments on the posterior dentition generated during anterior intrusion with different intrusion techniques in the maxillary and mandibular dental arch.

MATERIAL AND METHODS

Seven wire specimens were used for each of the following intrusive arches: Utility arch 0.016 x 0.016' Blue Elgiloy, Utility arch 0.017 x 0.025' TMA and Burstone Intrusion arch 0.017 x 0.025' TMA. The wires were inserted on bracketed dental arches constructed on maxillary Frasaco models, segmented mesially to the maxillary canines. Simulated intrusion from 0.0-3.0 mm was performed on the Orthodontic Measurement and Simulation System (OMSS). The forces and moments were recorded in all three planes of space at 0.1 mm increments and the values at 3.0 mm for all wires were used for all statistical evaluations. The data were analyzed, separately for the forces and moments, by means of two-way analysis of variance (ANOVA) with forces and moments serving as the dependent variables and intrusion technique and jaw (maxilla or mandible) as the independent variable. Post hoc multiple comparisons were performed using the Tukey test at .05 error rate.

RESULTS

The 0.016 x 0.016' Blue Elgiloy utility arch exerted the highest posterior extrusive forces, 15% higher than the 0.017 x 0.025' TMA utility and 40% higher in comparison with the 0.017 x 0.025' TMA Burstone intrusion arch.The lowest posterior moment in the sagittal plane was generated by the 0.017 x 0.025' TMA Burstone intrusion arch. The 0.016 x 0.016' Blue Elgiloy utility arch exerted 15% higher posterior moments and the 0.017 x 0.025' TMA utility 25% higher. Forces and moments were consistently larger for the mandible compared to the maxilla for the same intrusion technique.

CONCLUSIONS

The upper Burstone 0.017 x 0.025' TMA intrusion arch exerted the lowest forces/moments on posterior teeth. The highest forces were generated by the 0.016 x 0.016-inch Blue Elgiloy utility arch and the highest moments by the lower 0.017 x 0.025-inch TMA utility arch.

Long-term periodontal status of patients with mandibular lingual fixed retention

The purpose of this study was to evaluate the periodontal tissues of patients with mandibular fixed retention for long or short periods of time. A total of 64 individuals were selected for this study using the following inclusion criteria: long-term lingual fixed retention; identical type of lingual fixed retainer bonded with the same materials; no cavities, restorations, or fractures of the mandibular anterior teeth; absence of habits and occlusal interferences; and canine guidance bilaterally. The resultant sample comprised 32 patients (mean age 25 years) who had been in retention for a mean period of 9.65 years (range 9-11 years) and an equal number retained for a period between 3 and 6 months. Plaque, gingival, and calculus indices, probing pocket depth, marginal recession, and bone level at the mandibular six anterior teeth were recorded for both groups. Demographic, clinical, and radiographic data were investigated with conventional descriptive statistics. Comparisons of the different variables between the two participant groups (long- and short-term retention) were carried out using a Mann-Whitney test for indices (plaque, gingival, and calculus), and a Fisher's exact test (two sided) for the remaining variables. No significant difference was found with respect to the plaque and gingival indices and bone level between the two groups. The long-term group presented higher calculus accumulation, greater marginal recession, and increased probing depth (P < 0.05). The results of this study raise the question of the appropriateness of lingual fixed retainers as a standard retention plan for all patients regardless of their attitude to dental hygiene. They also emphasize the importance of individual variability and cautious application of retention protocols after a thorough consideration of issues related to the anatomy of tissues and oral hygiene.

Desmoplastic small round cell tumor of the pleura

Desmoplastic small round cell tumor (DSRCT) is a rare neoplasm with aggressive behavior. Usually it presents as a peritoneal mass, although other cases in various locations have been described. Since less than 10 cases of primary DSRCT in the pleura have been described, it is of interest to report a pediatric case arising from the pleura. The diagnosis was confirmed by molecular detection of the EWS/WT-1 fusion gene product. Multidisciplinary treatment with chemotherapy, radiotherapy, and surgical resection resulted in a progression-free survival time above the median survival, suggesting that this conventional approach could prove effective for this rare and very aggressive malignancy.

Expression of oncofetal RNA-binding protein CRD-BP/IMP1 predicts clinical outcome in colon cancer

The oncofetal CRD-BP/IMP1 RNA binding protein regulates posttranscriptionally a handful of RNA transcripts, implicated in cell adhesion and invadopodia formation and was recently identified as a target of the beta-catenin/Tcf transcription factor that is constitutively activated in colorectal carcinomas (CRCs). The expression of CRD-BP/IMP1 was studied in normal adult intestines and CRCs. In normal mucosa, CRD-BP/IMP1 immunoreactivity was observed in few scattered cells located predominantly at or near the bottom of the crypts, whereas in CRCs the protein was detectable in tumor cells of 50% of the specimens analyzed. CRD-BP/IMP1 mRNA expression was measured by qRT-PCR in 78 CRCs. Thirty-two (41%) of the specimens were negative or had negligible expression, whereas the remaining forty-six (59%) expressed a wide range of CRD-BP/IMP1 mRNA levels. CRD-BP/IMP1 mRNA expression correlated with that of the putative stem/progenitor cell marker Musashi-1 mRNA (p = 0. 035). CRD-BP/IMP1 positive tumors metastasized and/or recurred more frequently (p = 0.001) and its expression defined a group of patients with shorter survival (p = 0.014). Furthermore, in a multivariate analysis CRD-BP/IMP1 expression was found to be an independent predictor of survival (p = 0.015). For stage I & II patients, the differences in metastasis/recurrence and survival rates remained significant (p = 0.001 and 0.033, respectively). These findings indicate that CRD-BP/IMP1 positive tumors exhibit early disease dissemination and unfavorable prognosis.

Greek BRCA1 and BRCA2 mutation spectrum: two BRCA1 mutations account for half the carriers found among high-risk breast/ovarian cancer patients

127 Greek breast/ovarian cancer families were screened for germline BRCA1/2 mutations by dHPLC followed by direct sequencing. Our results indicated 16 and 5 breast/ovarian cancer families bearing deleterious mutations in the BRCA1 and BRCA2 genes, respectively. Two novel BRCA2 germline mutations (G4X and 3783del10) are reported here for the first time. Subsequent compilation of our present findings with previously reported mutation data reveals that in a total of 287 Greek breast/ovarian cancer families, 46 and 13 carry a deleterious mutation in BRCA1 and BRCA2, respectively. It should be noted that two BRCA1 mutations, 5382insC and G1738R, both located in exon 20, account for 46% of the families found to carry a mutation. Based on our mutation analysis results, we propose here a hierarchical, cost-effective BRCA1/2 mutation screening protocol for individuals of Greek ethnic origin. The suggested protocol can impact on the clinical management of breast-ovarian cancer families on a national healthcare system level.

Maxillary incisor torque with conventional and self-ligating brackets: a prospective clinical trial

OBJECTIVES

To test the hypothesis that the engagement mode of wire to bracket affects the buccolingual inclination of maxillary incisors in extraction and non-extraction treatment with self-ligating and conventional brackets.

DESIGN

A randomized clinical trial employing a random distribution of variables among the studied populations.

SETTING AND SAMPLE POPULATION

Private practice of one author. A total of 105 patients followed prospectively, were divided into two groups based on the inclusion of extraction in the treatment planning. These groups were further divided in two subgroups each, one receiving a self-ligating bracket and the other treated with a conventional Edgewise appliance of the same slot size and prescription.

EXPERIMENTAL VARIABLE

Difference in the buccolingual inclination of maxillary incisors before and after treatment with the two appliances across the two treatment groups (extraction and non-extraction).

OUTCOME MEASURE

Angular measurements of the Sella-Nasion and Nasion-A point to maxillary incisor axis.

RESULTS

No difference was found in the mean difference of the two angles measured for the two bracket groups studied.

CONCLUSION

Self-ligating brackets seem to be equally efficient in delivering torque to maxillary incisors relative to conventional brackets in extraction and non-extraction cases.

Chromosome analysis and molecular cytogenetic investigations of an epithelioid hemangioendothelioma

Epithelioid hemangioendothelioma is a rare, well-differentiated endothelial tumor with a wide spectrum of clinical behavior and for which genetic data are extremely limited. We present a case of an epithelioid hemangioendothelioma in a 22-year-old male, which was analyzed with multiple cytogenetic approaches. Conventional cytogenetic analysis detected structural abnormalities of 11q13 and 11q14, rings, and marker chromosomes. Multi-color FISH (mFISH) and high-resolution multi-color banding (mBAND) analyses demonstrated that the aberrations of chromosome 11 were deletions and that the ring and marker chromosomes consisted of 12(q14 approximately q21) material. Comparative genomic hybridization (CGH) analysis revealed gains of 11(q13 approximately q14) and 12(q11 approximately q21), loss of 11(q21 approximately qter), and 2 amplicons at 12(q12 approximately q13) and 12(q14 approximately q21). Our data indicate that a subset of epithelioid hemangioendotheliomas may be characterized by complex rearrangements involving deletions and gains of 11q and 12q amplifications. The present case also shows that, in order to describe and understand such complex chromosome aberrations, chromosome analysis must be complemented with several molecular cytogenetic techniques.

Intratumor genomic heterogeneity in breast cancer with clonal divergence between primary carcinomas and lymph node metastases

Conflicting theories of epithelial carcinogenesis disagree on the clonal composition of primary tumors and on the time at which metastases occur. In order to study the spatial distribution of disparate clonal populations within breast carcinomas and the extent of the genetic relationship between primary tumors and regional metastases, we have analyzed by comparative genomic hybridization 122 tissue samples from altogether 60 breast cancer patients, including 34 tumor samples obtained from different quadrants of 9 breast carcinomas, as well as paired primary-metastatic samples from 12 patients. The median intratumor genetic heterogeneity score (HS) was 17.4% and unsupervised hierarchical clustering analysis comparing the genetic features to those of an independent series of 41 breast carcinomas confirmed intratumor clonal divergence in a high proportion of cases. The median HS between paired primary breast tumors and lymph node metastases was 33.3%, but the number of genomic imbalances did not differ significantly. Clustering analysis confirmed extensive clonal divergence between primary carcinomas and lymph node metastases in several cases. In the independent series of 41 breast carcinomas, the number of genomic imbalances in primary tumors was significantly higher in patients presenting lymph node metastases (median = 15.5) than in the group with no evidence of disease spreading at diagnosis (median = 5.0). We conclude that primary breast carcinomas may be composed of several genetically heterogeneous and spatially separated cell populations and that paired primary breast tumors and lymph node metastases often present divergent clonal evolution, indicating that metastases may occur relatively early during breast carcinogenesis.

TP53 mutations are associated with a particular pattern of genomic imbalances in breast carcinomas

TP53 mutations play an important role in the development of several cancers and are present in 20-40% of all breast carcinomas, contributing to increased genomic instability. In order to address the relationship of mutated TP53 to genomic complexity, the present study analysed 61 breast carcinomas for TP53 mutations and compared mutation status with the pattern of genomic imbalances as assessed by comparative genomic hybridization (CGH). Twenty per cent of the present series of breast carcinomas harboured TP53 mutations. An increasing number of abnormalities, as identified by CGH (higher genomic complexity), correlated significantly with mutant TP53. Among the chromosome arms most commonly altered (in more than 20% of the tumours), loss of 8p and gain of 8q were associated with TP53 mutations, whereas loss of 16q was associated with wild-type TP53. By performing supervised hierarchical clustering analysis of the CGH data, a cluster of chromosome imbalances was observed that showed differences between wild-type and mutant TP53 cases. Among these, loss of chromosome arm 5q revealed the strongest correlation with altered TP53. To investigate further the most commonly deleted region of 5q, gene expression patterns from two publicly available microarray data sets of breast carcinomas were evaluated statistically. The expression data sets identified potential target genes, including genes involved in ubiquitination and the known TP53 target CSPG2. The genomic complexity of breast carcinomas as assessed by CGH is associated with TP53 mutation status; breast cancers with TP53 mutations display more complex genomes than do those with wild-type TP53. The pattern of genomic imbalances associated with mutant TP53 is non-random, with loss of chromosome arm 5q being particularly closely associated with TP53 mutations.

Cytogenetic manifestations of multiple myeloma heterogeneity

To investigate the genetic basis of the great heterogeneity observed in the clinical behavior of multiple myeloma (MM), a combined approach of G-banding, interphase fluorescence in situ hybridization (FISH), and multicolor FISH (M-FISH) was employed to analyze 70 samples from 53 patients with MM. G-banding revealed abnormal karyotypes in 77% of the cases. The origin of 31 chromosome markers was identified or revised by M-FISH. Combined metaphase karyotypic data and interphase FISH findings, using the immunoglobulin heavy-chain (IGH), IGH/cyclin D1 gene (CCND1), and D13S319 probes, revealed chromosome abnormalities in all evaluated patients and marked inter- and intratumor cytogenetic heterogeneity in the investigated MM samples. Cytogenetically unrelated clones were detected in 26% of the cases, mostly MM evaluated at diagnosis, whereas cytogenetic clonal evolution, manifested as related clones in 20% of the cases, was associated with disease progression. Among the 14q32 rearrangements, present in 66% of the cases, at least three cytogenetic subsets could be identified: one with t(11;14), usually without 13q14 deletion; another with other IGH changes, often 13q14 deletion, and hypodiploid modal chromosome number; and a third without changes in 14q32 but with abnormalities of chromosome 17. The correlation found between cytogenetic and clinicopathologic characteristics provided support for the concept that general genomic features in conjunction with specific chromosome rearrangements define the malignant phenotype in the various subsets of MM.

Metaphase and interphase cytogenetics in fibroadenomas of the breast

Short-term cultures of fifty-two samples of fibroadenomas were cytogenetically analyzed. Thirty-three of the successfully karyotyped fibroadenomas were further investigated for the presence of amplifications in the CCND1, c-MYC and HER/2-neu genes by means of FISH analysis. Compared to carcinomas, fibroadenomas seem to have less complex cytogenetic rearrangements and limited alterations on HER-2/neu, CCND1 and c-MYC loci. A cytogenetic subgroup of fibroadenomas with hyperdiploid karyotypes and only numerical changes was observed. Amplification of CCND1 seems to play a more substantial role in benign tumor progression. These findings confirm that fibroadenomas do have genetic alterations and support the hypothesis that a fibroadenoma subset displays changes also found in carcinomas, thus indicating that patients belonging to this group might have an increased risk for subsequent breast cancer.

Assessment of clonal relationships in ipsilateral and bilateral multiple breast carcinomas by comparative genomic hybridisation and hierarchical clustering analysis

The issue of whether multiple, ipsilateral or bilateral, breast carcinomas represent multiple primary tumours or dissemination of a single carcinomatous process has been difficult to resolve, especially for individual patients. We have addressed the problem by comparative genomic hybridisation analysis of 26 tumours from 12 breast cancer patients with multiple ipsilateral and/or bilateral carcinoma lesions. Genomic imbalances were detected in 25 of the 26 (96%) tumours. Using the genomic imbalances detected in these 26 lesions as well as those previously found by us in an independent series of 35 unifocal breast carcinomas, we compared a probabilistic model for likelihood of independence with unsupervised hierarchical clustering methodologies to determine the clonal relatedness of multiple tumours in breast cancer patients. We conclude that CGH analysis of multiple breast carcinomas followed by unsupervised hierarchical clustering of the genomic imbalances is more reliable than previous criteria to determine the tumours’ clonal relationship in individual patients, that most ipsilateral breast carcinomas arise through intramammary spreading of a single breast cancer, and that most patients with bilateral breast carcinomas have two different diseases.

Characterization of a novel large deletion and single point mutations in the BRCA1 gene in a Greek cohort of families with suspected hereditary breast cancer

BACKGROUND

Germline mutations in BRCA1 and BRCA2 predispose to breast and ovarian cancer. A multitude of mutations have been described and are found to be scattered throughout these two large genes. We describe analysis of BRCA1 in 25 individuals from 18 families from a Greek cohort.

METHODS

The approach used is based on dHPLC mutation screening of the BRCA1 gene, followed by sequencing of fragments suspected to carry a mutation including intron--exon boundaries. In patients with a strong family history but for whom no mutations were detected, analysis was extended to exons 10 and 11 of the BRCA2 gene, followed by MLPA analysis for screening for large genomic rearrangements.

RESULTS

A pathogenic mutation in BRCA1 was identified in 5/18 (27.7 %) families, where four distinct mutations have been observed. Single base putative pathogenic mutations were identified by dHPLC and confirmed by sequence analysis in 4 families: 5382insC (in two families), G1738R, and 5586G > A (in one family each). In addition, 18 unclassified variants and silent polymorphisms were detected including a novel silent polymorphism in exon 11 of the BRCA1 gene. Finally, MLPA revealed deletion of exon 20 of the BRCA1 gene in one family, a deletion that encompasses 3.2 kb of the gene starting 21 bases into exon 20 and extending 3.2 kb into intron 20 and leads to skipping of the entire exon 20. The 3' breakpoint lies within an AluSp repeat but there are no recognizable repeat motifs at the 5' breakpoint implicating a mechanism different to Alu-mediated recombination, responsible for the majority of rearrangements in the BRCA1 gene.

CONCLUSIONS

We conclude that a combination of techniques capable of detecting both single base mutations and small insertions/deletions and large genomic rearrangements is necessary in order to accurately analyze the BRCA1 gene in patients at high risk of carrying a germline mutation as determined by their family history. Furthermore, our results suggest that in those families with strong evidence of linkage to the BRCA1 locus in whom no point mutation has been identified re-examination should be carried out searching specifically for genomic rearrangements.