Dental Plaque, Oral Biofilm, Peri-implantitis
Conditions
Keywords
Titanium-6Aluminum-7Niobium alloy, Pagalinor, transmucosal implant abutment, implant crowns, temporary push-on rings, Variobase abutments
Brief summary
This in-vivo study investigates early (48h), mature (2 weeks) and long-term (3 months) biofilm formation and composition on temporary push-on cones (exchangeable conical rings) made of noble-alloy-based materials (Pagalinor, PA) in comparison to Titanium-6Aluminum-7Niobium alloy (TAN) presently used in the transmucosal portion of dental implant abutments.
Detailed description
Oral biofilm (dental plaque) consists of bacteria and their metabolic products as well as saliva components and food residues. It is recognizable as a tough and structured coating on teeth and artificial surfaces within the oral cavity. Plaque development is a physiological process that begins immediately after cleaning of the oral surface. If the biofilm is not removed by daily oral hygiene, it continues to mature while changing the structure and its microbial composition. Implant restorations comprise the osseous implant portion predominantly manufactured from titanium alloys, the transmucosal implant portion (in most implant systems as a separate abutment), and the clinical crown, which is in most systems extraorally cemented on an abutment and screw-retained onto the implant. According to current knowledge, microbial colonization of the implant abutment surface plays a significant role in the aetiology of peri-implantitis. This study investigates the antibacterial potential of a temporary push-on cone (conical ring) that could reduce the risk of bacterial related peri-implant diseases due to decreased biofilm susceptibility, compared to current available transmucosal materials, in the short- and long-run. The test material Pagalinor®2 (PA) is an established material in dental medicine and has proven to accumulate least biofilm in an in-vivo biofilm sampling model using removable splints. The control material consists of the current transmucosal implant abutment material Titanium-6Aluminum- 7Niobium alloy (TAN). The push-on rings are designed for repeated application along the transmucosal implant abutment portion with high precision fit and will allow biofilm sampling in the natural implant environment. Profound insight into the native homeostasis of biofilm formation will be obtained and therefore enhance the knowledge about long-term tissue response.
Interventions
DEVICERings made of PA (test)
Rings made of PA (test) 0.2mm in thickness are pushed on the conical titanium base (abutment) of implant crowns and are removed and replaced after 48h, 2 weeks and 3 months for quantification of the bacterial biofilm. Test rings are applied in a split-mouth design provided that 2 implants are present (total of 4 months study period), or one after the other when only 1 implant is present (total of 8 months study period).
DEVICERings made of TAN (control)
Rings made of TAN (control) 0.2mm in thickness are pushed on the conical titanium base (abutment) of implant crowns and are removed and replaced after 48h, 2 weeks and 3 months for quantification of the bacterial biofilm. Control rings are applied in a split-mouth design provided that 2 implants are present (total of 4 months study period), or one after the other when only 1 implant is present (total of 8 months study period).
Sponsors
University Hospital, Basel, Switzerland
ITI International Team for Implantology, Switzerland
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
DOUBLE (Subject, Investigator)
Masking description
Double-blinded with the patient not knowing which material is placed, and the investigator and laboratory technicians have no information about the ring material.
Intervention model description
All patients enrolled in the current investigation will wear both the test and control ring material for a within-subject comparison. Ideally, biofilm sampling can be performed in a split mouth design (randomly allocated materials within subjects) with one patient having two implants for placing the test and the control material at the same time. In addition, patients providing one implant, will receive test and control push-on rings in a randomly assigned order, so that both materials are assessed in a consecutive manner.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Informed Consent signed by the subject * Presence of one or more bone level titanium implant prior to insertion of the final restoration * No systemic illness * No heavy smoking (smoking \<10 cigarettes/day) * No pregnancy * No active periodontitis (probing pocket depth ≤4 mm) * No pharmacological treatment or antibiotic therapy during or up to three months before the study
Exclusion criteria
* Systemic illness (e.g. Diabetes) * Heavy smoking (smoking \>10 cigarettes/day) * Known or suspected non-compliance, drug or alcohol abuse * Pregnancy * Active periodontitis (probing pocket depth \>4 mm) * Pharmacological treatment or antibiotic therapy during or up to three months before the study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in total bacterial load formed on the removable rings of each material | at 48 hours after ring placement, 2 weeks after ring placement and 3 months after ring placement | Quantification of the bacterial load formed on the removable rings of each material by quantitative real-time PCR (qPCR) using primers specific to highly conserved regions of bacterial 16S rRNA genes. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in noninvasive laser doppler flowmetry | at baseline, 2 weeks after ring placement and 10 weeks after ring placement | Change in noninvasive laser doppler flowmetry to to measure the blood flow of mucosa next to the ring |
| Change in the cells of the peri-implant soft tissue | at 2 weeks after ring placement | To investigate the attachment of peri-implant soft tissues to implant materials, fibroblasts and junctional epithelial cells markers will be analysed using real-time quantitative PCR (RT-qPCR). |
| Change in bacterial composition (taxonomic diversity) between different materials at various time points by using metagenomic sequencing analysis | at baseline, 2 weeks after ring placement and 10 weeks after ring placement | To assess differences in bacterial composition (taxonomic diversity) between different materials at various time points by Illumina MiSeq sequencing. The taxonomy of each 16S rRNA gene sequence will be analyzed by Ribosomal Database Project (RDP) Classifier (http://rdp.cme.msu.edu/) against the SILVA (SSU123) 16S rRNA database using a confidence threshold of 70%. |
| Change in probing pocket depth (PPD) in mm | at baseline, 2 weeks after ring placement and 10 weeks after ring placement | Change in probing pocket depth (PPD) to investigate the inflammatory tissue response |
| Change in bleeding on probing (BoP) | at baseline, 2 weeks after ring placement and 10 weeks after ring placement | Recording bleeding on probing (BoP) to investigate the inflammatory tissue response |
Countries
Switzerland
Contacts
CONTACTNicola U. Zitzmann, Prof. Dr.
CONTACTLucia K. Zaugg, Dr. med. dent.
PRINCIPAL_INVESTIGATORNicola U. Zitzmann, Prof. Dr.
University Center for Dental Medicine Basel
Outcome results
None listed