Augmentation of the atrophic edentulous mandible by a bilateral two-step osteotomy with autogenous bone graft to place osseointegrated dental implants

Extensive resorption of the mandible increases the interarch space and rehabilitation with traditional dentures is often unsatisfactory due to the superficialization of intraoral muscles. A study of 19 patients who underwent augmentation of an atrophic mandible using a bilateral two-step osteotomy and interpositional bone graft technique is presented. Three horizontal bone cuts (one in the intraforamina and two in the molar region) were made and jointed together by two short vertical bone cuts mesialy to the mental nerve. The cranial fragment was lifted and the iliac bone graft was interposed recreating the correct intermaxillary relationship. A broad vascular pedicle was maintained during surgery, ensuring nutrition from the lingual side, essential to reduce resorption of the bone graft and cranial fragment. 141 Biomet 3i Osseotite^® implants were placed. Patients were rehabilitated with a full-arch implant-supported fixed prosthesis or an implant-supported overdenture. This clinical study describes the resorption process over a 4 year follow-up. 3 of 19 suffered from persistent neurosensitive disturbances. In conclusion, bilateral two-step osteotomy in association with interpositional bone graft is a reliable surgical means to recreate the anatomical morphology of the mandible.     

Renal impairment and its impact on clinical outcomes in patients who are critically ill with COVID-19: a multicentre observational study

Renal impairment is common in patients who are critically ill with coronavirus disease-19 (COVID-19). We examined the association between acute and chronic kidney disease with clinical outcomes in 372 patients with coronavirus disease-19 admitted to four regional intensive care units between 10 March 2020 and 31 July 2020. A total of 216 (58%) patients presented with COVID-19 and renal impairment. Acute kidney injury and/or chronic kidney disease was associated with greater in-hospital mortality compared with patients with preserved renal function (107/216 patients (50%) (95%CI 44–57) vs. 32/156 (21%) (95%CI 15–28), respectively; p < 0.001, relative risk 2.4 (95%CI 1.7–3.4)). Mortality was greatest in patients with renal transplants (6/7 patients (86%) (95%CI 47–100)). Mortality rates increased in patients with worsening renal injury according to the Kidney Disease: Improving Global Outcomes classification: stage 0 mortality 33/157 patients (21%) (95%CI 15–28) vs. stages 1–3 mortality 91/186 patients (49%) (95%CI 42–56); p < 0.001, relative risk 2.3 (95%CI 1.7–3.3). Survivors were less likely to require renal replacement therapy compared with non-survivors (57/233 patients (24%) vs. 64/139 patients (46%), respectively; p < 0.001, relative risk 1.9 (95%CI 1.4–2.5)). One-fifth of survivors who required renal replacement therapy acutely in intensive care continued to require renal support following discharge. Our data demonstrate that renal impairment in patients admitted to intensive care with COVID-19 is common and is associated with a high mortality and requirement for on-going renal support after discharge from critical care. Our findings have important implications for future pandemic planning in this patient cohort.     

Evaluation of Helicobacter pylori with a stool antigen assay in frail, elderly patients

OBJECTIVE: Helicobacter pylori infection has not been studied thoroughly in elderly patients. The aim of this study was to evaluate the reliability of stool antigen assay (HpSA) in the assessment of H. pylori infection in hospitalized, frail, elderly patients. MATERIALS AND METHODS: The study population consisted of 85 consecutively recruited elderly patients (> or =65 years old) hospitalized between May 1999 and December 2001 with diagnostic indications for upper gastrointestinal endoscopy. Twenty-nine subjects had been receiving treatment with proton-pump inhibitors (PPIs), such as omeprazole (10-20 mg/day) for 2-15 days, and 56 were not receiving treatment. HpSA was evaluated versus UBT (urea breath test), serology and histology: patients with at least two positive results out of the latter three tests were considered positive for H. pylori infection, while patients with at least two negative tests out of three were considered negative. RESULTS: The sensitivity and specificity of HpSA in the 56 untreated patients were, respectively, 76% (true positives TP = 22; false negatives FN = 7) and 93% (true negatives TN = 25; false positives FP = 2). The sensitivity and specificity of HpSA in the 29 patients on PPI treatment were, respectively, 82% (TP = 9; FN = 2) and 83% (TN = 15; FP = 3). CONCLUSIONS: HpSA is an accurate, non-invasive and easy method for diagnosing H. pylori infection in elderly patients.     

Primary hyperparathyroidism and the presence of kidney stones are associated with different haplotypes of the calcium-sensing receptor

INTRODUCTION: Three single-nucleotide polymorphisms in the calcium-sensing receptor gene (CASR) encoding the missense substitutions A986S, R990G, and Q1011E have been associated with normal variation in extracellular calcium homeostasis, both individually and in haplotype combination. The aim of this study was to examine haplotype associations in primary hyperparathyroidism (PHPT). PATIENTS AND METHODS: Patients with sporadic PHPT (n = 237) were recruited from endocrine clinics and healthy controls (n = 433) from a blood donor clinic, and levels of serum calcium, albumin, and PTH were measured. In PHPT patients, urinary calcium/creatinine clearances and bone mineral density at spine and femoral neck were measured and the presence of kidney stones and vertebral fractures identified. The CASR single-nucleotide polymorphisms were haplotyped by allele-specific sequencing. RESULTS: Four haplotypes (ARQ, SRQ, AGQ, and ARE) of eight were observed, in keeping with significant linkage disequilibrium, but haplotype frequencies did not show significant Hardy-Weinberg disequilibrium. The SRQ haplotype was more common in PHPT (125 of 474 alleles) than in controls (170 of 866 alleles, P = 0.006) and showed a significant (P = 0.006) gene-dosage effect. There was no significant association between haplotype and bone mineral density or fractures, but association with kidney stones was significant (P = 0.0007). In the stone-forming subgroup, the SRQ haplotype was underrepresented and AGQ overrepresented. Patients bearing the AGQ haplotype had an odds ratio of 3.8 (95% confidence interval, 1.30-11.3) for presentation with renal stones compared with the rest. CONCLUSION: Our data indicate that the CASR SRQ haplotype is significantly associated with PHPT in our population. Within the PHPT patient population, the AGQ haplotype is significantly associated with kidney stones.     

Spirometrically gated high-resolution CT findings in COPD: lung attenuation vs lung function and dyspnea severity

STUDY OBJECTIVES: The aim of this study was to investigate the relationship between high-resolution CT (HRCT) lung attenuation measurements, acquired under spirometric control of inspiratory and expiratory lung volume, and pulmonary dysfunction as well as dyspnea severity in patients with COPD.Patients and design: In 51 patients with COPD, we compared by linear regression, univariate and multivariate logistic regression airflow limitation (FEV(1)/vital capacity [VC]), hyperinflation (percentage of predicted residual volume [RV%]), parenchymal loss (percentage of predicted diffusing capacity of the lung for carbon monoxide [Dlco%]), and Medical Research Council (MRC) dyspnea scale with relative area with attenuation values < - 950 HU at 90% of VC [RAI(950)] and < - 910 HU at 10% of VC, respectively, and with mean lung attenuation measured at the same levels of VC (mean CT lung density at 10% of VC, and mean CT lung density at 90% of VC [MeanCTEXP]). RESULTS: All HRCT attenuation measurements were significantly related with functional abnormalities and dyspnea severity. In multivariate logistic models, with 1 indicating worse changes in dichotomous outcome variables, MeanCTEXP independently predicted FEV(1)/VC (odds ratio [OR], 0.24; 95% confidence interval [CI], 0.11 to 0.56), RV% (OR, 0.57; 95% CI, 0.42 to 0.77), and MRC dyspnea scale (OR, 0.63; 95% CI, 0.48 to 0.82), while RAI(950) independently predicted Dlco% (OR, 1.90; 95% CI, 1.37 to 2.65). CONCLUSIONS: Spirometrically gated measurements of HRCT lung attenuation reflect differently functional changes and dyspnea perception in COPD. Inspiratory measurements assess the extent of emphysematous tissue loss, and expiratory measurements may reflect airflow limitation and lung hyperinflation with attendant dyspnea perception. Pulmonary dysfunction in COPD cannot be assessed by a single modality of lung attenuation measurement.     

Four-year efficacy of cardiac resynchronization therapy on exercise tolerance and disease progression: the importance of performing atrioventricular junction ablation in patients with atrial fibrillation.

OBJECTIVES: The goal of this study was to investigate the effects of cardiac resynchronization therapy (CRT) in heart failure patients with permanent atrial fibrillation (AF) and the role of atrioventricular junction (AVJ) ablation. BACKGROUND: Cardiac resynchronization therapy has been proven effective in heart failure patients with sinus rhythm (SR). However, little is known about the effects of CRT in heart failure patients with permanent AF. METHODS: Efficacy of CRT on ventricular function, exercise performance, and reversal of maladaptive remodeling process was prospectively compared in 48 patients with permanent AF in whom ventricular rate was controlled by drugs, thus resulting in apparently adequate delivery of biventricular pacing (>85% of pacing time), and in 114 permanent AF patients, who had undergone AVJ ablation (100% of resynchronization therapy delivery). The clinical and echocardiographic long-term outcomes of both groups were compared with those of 511 SR patients treated with CRT. RESULTS: Both SR and AF groups showed significant and sustained improvements of all assessed parameters (model p < 0.001 for all parameters). However, within the AF group, only patients who underwent ablation showed a significant increase of ejection fraction (p < 0.001), reverse remodeling effect (p < 0.001), and improved exercise tolerance (p < 0.001); no improvements were observed in AF patients who did not undergo ablation. CONCLUSIONS: Heart failure patients with ventricular conduction disturbance and permanent AF treated with CRT showed large and sustained long-term (up to 4 year) improvements of left ventricular function and functional capacity, similar to patients in SR, only if AVJ ablation was performed.     

Acute comparative effect of right and left ventricular pacing in patients with permanent atrial fibrillation

We tested the hypothesis that left ventricular (LV) pacing is superior to right ventricular (RV) apical pacing in patients undergoing atrioventricular (AV) junction ablation and pacing for permanent atrial fibrillation.The potential benefit of LV over RV pacing needs to be evaluated without the confounding effect of other variables that can influence cardiac performance.An acute intrapatient comparison of the QRS width and echocardiographic parameters between RV versus LV pacing was performed within 24 h after ablation in 44 patients. Both modes of pacing were also compared with pre-implantation values.Compared with RV pacing, LV pacing caused a 5.7% increase in the ejection fraction (EF) and a 16.7% decrease in the mitral regurgitation (MR) score; the QRS width was 4.8% shorter with LV pacing. Similar results were observed in patients with or without systolic dysfunction and/or native left bundle branch block, except for a greater improvement in MR in the latter group. Compared with pre-ablation measures, the EF increased by 11.2% and 17.6% with RV and LV pacing, respectively; the MR score decreased by 0% and 16.7%; and the diastolic filling time increased by 12.7% and 15.6%.Rhythm regularization achieved with AV junction ablation improved EF with both RV and LV pacing; LV pacing provided an additional modest but favorable hemodynamic effect, as reflected by a further increase of EF and reduction of MR. The effect seems to be equal in patients with both depressed and preserved systolic functions and in those with and without native left bundle branch block.     

Influence of cortical bone anchorage on the primary stability of dental implants

Purpose

This retrospective chart review study assessed patient records to determine implant insertion torque (IT) and implant stability quotient (ISQ) values during implant placement to evaluate the correlation with cortical bone anchorage (mono- or bicortical).

Methods

Primary stability data (IT during implant placement surgery and ISQ values immediately after implant placement) and cone beam computed tomography of 33 patients (165 implants) were assessed. Patients were divided into the following groups: G1, implants with apical cortical bone contact; G2, implants with bicortical bone contact (apical and cervical regions); and G3, implants with cervical cortical bone contact.

Results

Sixty-eight implants were excluded due to cortical bone contact on regions other than implant apical or cervical. Ninety-seven implants were therefore assessed for this study. No implant failure was found after a mean 70.42-month follow-up time. Implants with bicortical anchorage (G2) showed higher IT (64.1 Ncm) during implant placement and higher ISQ values (76) (p?<?0.05). Monocortical implants (G1, apical, and G3, cervical) showed similar IT (G1 52.3 and G3 54.3) and ISQ values (G1 71.9 and G3 73) (p?>?0.05). No correlation (Pearson correlation coefficient) was found between the two stability measurement devices for the different cortical bone anchorages that were analyzed (G1 0.190, G2 0.039, and G3 ??0.027) (p?>?0.05).

Conclusions

Insertion torque values and implant stability quotients were influenced by cortical bone contact. No significant correlation was found between IT and ISQ values—higher insertion torque values do not necessarily lead to higher implant stability quotients.

     

Osteoporosis in beta-thalassaemia major patients: analysis of the genetic background

Regular blood transfusions from infancy until adulthood in beta-thalassaemia major patients have substituted severe bone deformities with less marked skeletal lesions as osteoporosis. Osteoporosis is characterized by low bone mass and disruption of bone architecture, resulting in reduced bone strength and increased risk of fractures. Genetic factors have an important role in determining bone mineral density (BMD). We have investigated the possible association between BMD and two polymorphisms in 135 beta-thalassaemic patients: (i) a substitution G-->Tau in a regulatory region of the COLIA1 gene encoding for the major protein of bone (type 1 collagen), and (ii) a one-base deletion in intron 4 (713-8del C) of transforming growth factor beta 1 (TGF-beta1) gene. We have found a remarkable incidence (90%) of osteopenia and osteoporosis among regularly transfused patients. Bone mass was lower in men than in women (P = 0.0023), with a more prevalent osteopenia/osteoporosis of the spine in men than in women (P = 0. 001). The sample was stratified on the basis of BMD expressed as Z-score, i.e. normal, osteopenic and osteoporotic patients, and genotype frequencies of each group were evaluated. TGF-beta1 polymorphism failed to demonstrate a statistical difference in BMD groups. However, subjects with heterozygous or homozygous polymorphism of the COLIA1 gene showed a lower BMD than subjects without the sequence variation (P = 0.012). The differences among genotypes were still present when the BMD was analysed as adjusted Z-score and when men and women were analysed separately (P = 0.022 and 0.004 respectively), with men more severely affected. Analysis of COLIA1 polymorphism could help to identify those thalassaemic patients at risk of osteoporosis and fractures.