Evaluation of different materials used for sealing of implant abutment access channel and the peri-implant sulcus microbiota: A 6-month, randomized controlled trial.

OBJECTIVE: Peri-implantitis has been attributed to a myriad of factors, including microleakage at the abutment-implant interface. Implant abutment access channel sealing materials (IACSM) are readily used in implant dentistry, with little evidence on their effect on microleakage. This study aims to evaluate the effect of IACSM on the microbial composition in the implant access channel and the peri-implant sulcus. METHODS: A total of n = 8 patients (64 implants) were included in this single-blinded, randomized controlled trial, whereas four different materials (cotton, polytetrafluoroethylene [PTFE], synthetic foam, or polyvinyl siloxane [PVS]) were randomly placed as an IACSM. Following 6 months, microbial analysis was completed on the IACSM and samples from the peri-implant sulci via PCR and high-throughput sequencing. Bacterial samples on the IACSM and in the peri-implant sulci were classified according to Socransky's microbial complexes. RESULTS: There was a preponderance of early colonizing bacteria within the IACSM, while the peri-implant sulci were dominated by Orange complex bacteria. The proportion of Red and Orange complex members on the IACSM was significantly less than in the peri-implant sulci. The proportion of Green, Yellow, and Blue complex members found on the IACSM was significantly greater than in the peri-implant sulci. Atopobium, a diverse species not included in the microbial complexes, was frequently detected in the peri-implant sulcus samples. CONCLUSIONS: No detectable effects of IACSM on the microbial community in the peri-implant sulcus or on the IACSM were identified. Variation of bacterial species was most dependent on the individual patient. No significant differences were found in the periodontal parameters between the different treatment groups.

Glycogen Storage Disease Ib and Severe Periodontal Destruction: A Case Report.

Background: Glycogen storage diseases (GSDs) are genetic disorders that result from defects in the processing of glycogen synthesis or breakdown within muscles, liver, and other cell types. It also manifests with impaired neutrophil chemotaxis and neutropenic episodes which results in severe destruction of the supporting dental tissues, namely the periodontium. Although GSD Type Ib cannot be cured, associated symptoms and debilitating oral manifestations of the disease can be managed through collaborative medical and dental care where early detection and intervention is of key importance. This objective of the case report was to describe a child with GSD Ib and its associated oral manifestations with microbial, immunological and histological appearances. Case Presentation: An eight-year-old Hispanic male with a history of GSD type Ib presented with extensive intraoral generalized inflammation of the gingiva, ulcerations and bleeding, and intraoral radiographic evidence of bone loss. Tannerella forsythia was readily identifiable from the biofilm samples. Peripheral blood neutrophils were isolated and a deficient host response was observed by impaired neutrophil migration. Histological evaluation of the soft and hard tissues of the periodontally affected primary teeth showed unaffected dentin and cementum. Conclusions: This case illustrates the association between GSD Ib and oral manifestations of the disease. A multi-disciplinary treatment approach was developed in order to establish healthy intraoral conditions for the patient. Review of the literature identified several cases describing GSD and its clinical and radiographic oral manifestations; however, none was identified where also microbial, immunological, and histological appearances were described.

Osteogenic Potential of Gingival Mesenchymal Stem Cells Over Titanium Machined Surfaces.

PURPOSE: To evaluate the biochemical composition of bone nodules deposited by gingival mesenchymal stem cells (GMSCs) over titanium machined surfaces in vitro. MATERIALS AND METHODS: GMSCs were isolated from healthy gingival tissues of patients undergoing crown-lengthening surgical procedures. GMSCs were characterized following the International Society for Cellular Therapy guidelines. After incubation of the GMSCs with titanium discs, osteogenic differentiation was induced for 28 days. Osteogenic lineage was confirmed by means of Alizarin Red S staining. Bone nodule morphology and deposition by GMSCs were characterized by scanning electron microscopy (SEM). An elemental analysis of the bone nodules was done using energy-dispersive x-ray spectroscopy (EDS). The biochemical composition of these nodules was further characterized via Raman spectroscopy, with native alveolar bone used as a control. RESULTS: GMSCs adhered and proliferated on the titanium discs and exhibited a spindle-shaped fibroblast-like morphology under standard culture conditions. Their phenotype was confirmed by the expression of CD105, CD90, CD73, and CD146, observed using flow cytometry. Deposits of calcium bone nodules were evident in the cultures after staining with Alizarin Red S, but were absent in the controls. Calcium and phosphate, the major components of hydroxyapatite, were present in the bone nodules, as shown by means of the EDS analysis. The results obtained from Raman spectra of these nodules showed the phosphate ions (ν[PO4³â»], ~960 cm¹), amide III (δ[NH], ~1,245 cm⁻¹), CH2 scissors (~1,451 cm⁻¹), amide I (ν[C = O], ~1,667 cm⁻¹), and ν(CH) (2,800-3,100 cm⁻¹) bands were similar to those observed in native bone. CONCLUSION: GMSCs can deposit a bone-like mineral highly similar to native bone (HA) over titanium surfaces. Ongoing studies are aimed at determining whether GMSCs can deposit a similar bone matrix/tissue over removed failed dental implants. If HA can be placed over removed failed dental implants, it may be possible to re-osseointegrate dental implants that are failing as a result of peri-implantitis in vivo.

Enhanced Lateral Bone Augmentation With a Perforated Resorbable Barrier Membrane.

INTRODUCTION: To the best of the authors' knowledge, this is the first case report to describe the use of a perforated resorbable barrier membrane (PRBM) to enhance lateral bone augmentation for implant site development. CASE PRESENTATION: A 41-year-old female presented to the Advanced Specialty Education Program in Periodontics at Stony Brook University, Stony Brook, New York, for implant consultation regarding a missing maxillary right lateral incisor. The tooth had been lost as a result of trauma 10 years prior to presentation. Clinical examination and radiographs showed significant horizontal ridge deficiency (<5 mm) that supported a staged intervention. Horizontal bone augmentation was performed following guided bone regeneration principles using a mineralized mixed corticocancellous (70:30) allograft followed by a PRBM. A cone beam computed tomography scan was obtained before surgery and 8 months after treatment, from which volumetric width changes were quantified. A bone biopsy was obtained at the time of implant placement to measure new vital bone (NVB) formation, residual graft (RG) particles, and connective tissue (CT) formation. Dimensional width changes were assessed during reentry for implant placement. The lateral bone gain was 5.0 mm, clinically and radiographically. Histologically, the amount of NVB formation, RG particles, and CT infiltration was 38.1%, 38.9%, and 23.1%, respectively. Implant placement was uneventful, with no further need for bone augmentation. CONCLUSIONS: Previous studies using similar techniques and regenerative materials have shown an average of 3.5 mm of horizontal bone augmentation. The use of a PRBM appeared to significantly enhance lateral bone augmentation. An ongoing clinical trial is underway to confirm these results.

Retrieval of Displaced Implant Attributable to an Ill-Fitting Denture From the Maxillary Sinus Six Months After Transcrestal Sinus Floor Augmentation and Implant Placement.

INTRODUCTION: Asymptomatic displacement of dental implants into the maxillary sinus after a transcrestal sinus augmentation is a rare complication that can occur when there is poor bone quality and minimal residual bone height. Patient compliance with postoperative appointments and failure to comply with denture-wearing instructions are critical contributing factors. To the best of the authors' knowledge, no cases of implant dislodgement attributable to a removable prosthesis have been reported in the literature, although some studies have suggested that improper occlusal forces can cause a long-standing implant to develop peri-implantitis and subsequent displacement of an implant into the sinus cavity. CASE PRESENTATION: A 71-year-old female presented 6 months after undergoing transcrestal sinus lift and implant surgery that involved a modified Summers technique using mineralized solvent-dehydrated cancellous bone allograft and placement of six maxillary implants. A displaced dental implant was retrieved from the right maxillary sinus, which had an intact Schneiderian membrane. The patient was asymptomatic and infection free. The displaced implant was accessed and retrieved via a lateral window sinus technique. No clinical signs of sinus infection were evident, and there were no additional complications during the 2-year follow-up period. CONCLUSION: This case report demonstrates a technique for the retrieval of implants that have been dislodged and migrated into the maxillary sinus cavity caused by an ill-fitting denture and improper masticatory forces.