Concomitant versus sequential therapy for the treatment of Helicobacter pylori infection: a Greek randomized prospective study

Objective: The objective of this study is to compare, in Greece, a region with >20% local resistance to clarithromycin, the efficacy rates of the concomitant versus the sequential H. pylori eradication therapy. Materials and methods: Our prospective randomized study included 364 patients with newly diagnosed H. pylori infection, randomized to receive a 10-day concomitant or 10-day sequential therapy. Treatment outcome was assessed by C¹³-urea breath test at least 4 weeks after therapy. Intention to treat (ITT) and per protocol (PP) analysis of the eradication rates were performed. Secondary end points included patient compliance and safety. Results: The concomitant therapy group achieved statistically significant higher eradication rates when compared with the sequential treatment group, both in the ITT and in the PP analysis (84.6% versus 70.9%, p?=?0.002, and 90.6% versus 78.1%, p?=?0.001, respectively), after adjusting for age, gender, smoking status, and the presence or not of ulcer and/or non-ulcer dyspepsia. Both groups displayed excellent compliance rates (99.5% for the concomitant therapy group and 96.2% for the sequential therapy group, p?=?0.067). Regarding treatment safety, major adverse events that led to the discontinuation of both regimens were few, with no statistical difference between the two groups (7.0% for the concomitant therapy group and 2.9% for the sequential therapy group). Conclusions: Concomitant therapy led to statistically significant higher eradication rates over sequential therapy. Both therapies showed excellent compliance and an acceptable safety profile. The 10-day quadruple concomitant scheme should be the adopted for first-line H. pylori eradication in Greece.     

Biallelic loss of function variants in PPP1R21 cause a neurodevelopmental syndrome with impaired endocytic function

Next‐generation sequencing (NGS) has been instrumental in solving the genetic basis of rare inherited diseases, especially neurodevelopmental syndromes. However, functional workup is essential for precise phenotype definition and to understand the underlying disease mechanisms. Using whole exome (WES) and whole genome sequencing (WGS) in four independent families with hypotonia, neurodevelopmental delay, facial dysmorphism, loss of white matter, and thinning of the corpus callosum, we identified four previously unreported homozygous truncating PPP1R21 alleles: c.347delT p.(Ile116Lysfs*25), c.2170_2171insGGTA p.(Ile724Argfs*8), c.1607dupT p.(Leu536Phefs*7), c.2063delA p.(Lys688Serfs*26) and found that PPP1R21 was absent in fibroblasts of an affected individual, supporting the allele's loss of function effect. PPP1R21 function had not been studied except that a large scale affinity proteomics approach suggested an interaction with PIBF1 defective in Joubert syndrome. Our co‐immunoprecipitation studies did not confirm this but in contrast defined the localization of PPP1R21 to the early endosome. Consistent with the subcellular expression pattern and the clinical phenotype exhibiting features of storage diseases, we found patient fibroblasts exhibited a delay in clearance of transferrin‐488 while uptake was normal. In summary, we delineate a novel neurodevelopmental syndrome caused by biallelic PPP1R21 loss of function variants, and suggest a role of PPP1R21 within the endosomal sorting process or endosome maturation pathway.     

Use of titanium mesh for staged localized alveolar ridge augmentation: clinical and histologic-histomorphometric evaluation

The use of titanium mesh for localized alveolar ridge augmentation was evaluated by clinical, radiographic, laboratory, and histologic-histomorphometric evaluation. Seventeen patients participated in this study. All patients required localized alveolar ridge augmentation before placement of dental implants. An equal mixture of autogenous bone graft and inorganic bovine mineral (Bio-Oss) was used as a bone graft material. Autogenous bone graft was harvested intraorally. Titanium mesh was submerged for 8.47 months (SD 2.83). Impressions were taken intraorally before bone grafting, 6 months after bone grafting, and 6 months after implant placement. Impressions were used to measure the volume of alveolar ridge augmentation and provide linear laboratory measurements regarding the results of bone augmentation. Bone quality (type II-IV) was recorded during implant surgery. Standardized linear tomographs were taken before bone grafting and before implant placement. A biopsy was harvested with a trephine bur from the grafted area during implant surgery for histologic-histomorphometric evaluation. In all cases the grafted area had adequate bone volume and consistency for placement of dental implants. Early mesh exposure (2 weeks) was observed in 2 patients, and late exposure (>3 months) was observed in 4 patients. Volumetric laboratory measurements indicated 0.86 cc (SD 0.69) alveolar augmentation 1 month after bone grafting, 0.73 cc (SD 0.60) 6 months after bone grafting, and 0.71 cc (SD 0.57) 6 months after implant placement. This indicated 15.11% resorption 6 months after bone grafting, and no further resorption occurred after implant placement. Linear laboratory measurements indicated vertical augmentation of 2.94 mm (SD 0.86) 1 month after bone grafting, 2.59 mm (SD 0.91) 6 months after bone grafting, and 2.65 mm (SD 1.14) 6 months after implant placement. The corresponding measurements for labial-buccal augmentation were 4.47 mm (SD 1.55), 3.88 mm (SD 1.43), and 3.82 mm (SD 1.47). Radiographic evaluation indicated 2.56 mm (SD 1.32) vertical augmentation and 3.75 mm (SD 1.33) labial-buccal augmentation. Histomorphometric evaluation indicated 36.47% (SD 10.05) new bone formation, 49.18% (SD 6.92) connective tissue, and 14.35% (SD 5.85) residual Bio-Oss particles; 44.65% (SD 22.58) of the Bio-Oss surface was in tight contact with newly formed bone. The use of titanium mesh for localized alveolar ridge augmentation with a mixture of autogenous intraorally harvested bone graft and Bio-Oss offered adequate bone volume for placement of dental implants. Intraorally harvested autogenous bone graft mixed with Bio-Oss under a titanium mesh offered 36.47% new bone formation, and 15.11% resorption occurred 6 months after bone grafting.     

Conversion of a complete denture to a provisional implant-supported,screw-retained fixed prosthesis for immediate loading of a completely edentulous arch

This article describes the fabrication of a provisional implant-supported, screw-retained restoration for immediate loading of a completely edentulous arch. The technique can be applied to patients with partially edentulous arches as well. Until immediate loading of dental implants becomes a well-documented treatment modality, the described method should not be applied on a routine basis or without careful evaluation.     

The effectiveness of auxiliary features on a tooth preparation with inadequate resistance form

STATEMENT OF PROBLEM: No study has evaluated the efficacy of auxiliary tooth preparation elements for crowns with originally reduced resistance form. PURPOSE: This study evaluated the effects of different auxiliary preparation features on the resistance form of crowns with reduced axial wall and total occlusal convergence. MATERIAL AND METHODS: An Ivorine tooth was prepared on a milling machine with 20-degree total occlusal convergence (TOC), 2.5 mm of occlusocervical dimension, and a shoulder finish line. This design lacked geometric resistance form. The crown preparation was subsequently modified to include mesiodistal grooves, mesiodistal boxes, buccolingual grooves, occlusal inclined planes, an occlusal isthmus, and reduced TOC in the axial wall from 20 to 8 degrees TOC in the cervical 1.5 mm of the axial wall. The grooves and boxes were placed into the tooth with the same 20-degree TOC as the initial axial walls. Ten standardized metal dies were used for each preparation design. Standardized complete metal crowns were fabricated for all specimens. The metal crowns were cemented on metal dies with resin-modified glass ionomer cement. A strain gauge was placed at the mid-lingual cervical area of each crown preparation margin. The resistance of each specimen was evaluated when force was applied at a 45-degree angulation to the long axis of the die in a lingual to buccal direction. The peak loads during crown dislodgment, as well as the tensile stress at the mid-lingual cervical area, were measured using a universal testing machine (Kgs) for each specimen. The control group consisted of 10 dies, with the original crown preparation having no geometric resistance form and no auxiliary preparation features. Strain gauges provided the force (Kgs) that resulted in electric currency disrupt at the crown/die interface, thus providing data regarding the force required for slight crown micromovement (2 microm). Data between control and experimental groups were compared using the Mann-Whitney U test (alpha=.05). RESULTS: Proximal grooves, proximal boxes, buccolingual grooves, occlusal inclined planes, and occlusal isthmuses were not effective at increasing a crown's resistance to dislodgement when the tooth preparation lacked resistance. The only crown modification that offered enhanced resistance form when compared with the control group was the reduced TOC in the cervical half of the axial wall. CONCLUSION: Within the limitations of this in vitro study the crown preparation modification that significantly enhanced the resistance form of a compromised tooth preparation was reducing the TOC at the cervical aspect of the axial wall. Placing auxiliary retentive features such as grooves and boxes into a compromised tooth preparation (2.5 mm occlusocervical dimension and 20-degree TOC) was not effective when these retentive features possessed the same 20-degree TOC as the prepared axial walls.     

Effects of sealing the perforated sinus membrane with a resorbable collagen membrane: a pilot study in humans

The effects of repairing the perforated sinus membrane with collagen membrane are unknown. The purpose of this pilot study was to clinically, histologically, and histomorphometrically evaluate the results of repairing the perforated sinus membrane with resorbable collagen membrane. A split-mouth design was followed in the current study. Five subjects requiring bilateral sinus grafting were included in the study, where one site was accidentally perforated during sinus augmentation procedures and the other site was not perforated. The perforated sites were repaired with a resorbable collagen membrane. Dental implants were placed at a second stage and biopsies were harvested from both sinuses. New bone formation was measured for all sites. Implant survival was recorded at second-stage surgery. Nonperforated sites demonstrated significantly more bone formation (34.40%) than perforated sites (12.80%) (P = .016). Implant survival at second-stage surgery was significantly inferior in perforated sites (54.5%) when compared with nonperforated sites (100%) (P = .0146). The study demonstrated that perforation and repair of the Schneiderian membrane can compromise new bone formation and implant survival rate.     

Clinical and histologic evaluation of the use of mandibular tori as donor site for mandibular block autografts: report of three cases

The present paper reports on three patients who underwent localized alveolar ridge augmentation using block autografts harvested from the mandibular tori. Autogenous particulate bone graft was placed at the periphery of the block. Resorbable collagen membrane was placed above the graft material. Implant placement surgery followed at 6 to 16 months after bone grafting. During implant surgery, a biopsy was taken from the block autograft. Clinical evaluation revealed incorporation of the graft material at the recipient site. No donor site complication was noted. Histologic evaluation suggested that the block autograft was vital and in an active remodeling phase at the time of implant placement. Impressions were made intraorally before and 6 months after bone grafting. Laboratory measurements revealed 13% resorption at 6 months after bone grafting while 0.53 mL of ridge augmentation was achieved 6 months after bone grafting. Linear tomographs indicated 4.33 mm of lateral alveolar ridge augmentation. This report suggests that block autografts harvested from the mandibular tori may have the potential to maintain their vitality after bone grafting, while they may demonstrate resorption rates similar to those of autografts harvested from other intraoral donor sites.     

Clinical radiographic,and histologic evaluation of maxillary bone reconstruction by using a titanium mesh and autogenous iliac graft: a case report

The current clinical report describes the use of titanium mesh for maxillary alveolar ridge augmentation. Autogenous bone graft was harvested from the iliac crest and was loaded on a titanium mesh that was left in the patient's maxilla for 7 months before it was removed. Twelve months after the bone grafting procedure the patient received 10 implants on the maxilla, and a biopsy was taken from the augmented ridge. CT scan examination was performed before and after the maxillary ridge augmentation. Clinical evaluation revealed successful integration of the graft. The radiographic analysis demonstrated that a 10-mm vertical ridge augmentation had been achieved. Histologic evaluation revealed remnants of the autogenous bone graft still present, whereas the grafted area had a reduced remodeling activity. The clinical report demonstrated the potential of the titanium mesh to achieve extensive alveolar ridge augmentation, whereas the augmented ridge may possess an inferior capability forbone remodeling.