Investigating Implant Surface Effect on Osseointegration: NGA vs. ModSLA

A Randomised Clinical Trial Investigating Effect of Implant Surface Characteristic on Crestal Marginal Bone Loss, Inflammatory Response and Aesthetic Outcomes: Novel Gradient Anodized and Sandblasted Large-grit Acid-etched Implant Surfaces

This study aims to characterise the stability of crestal bone levels one year after loading, the associated aesthetic outcomes, immunological response, prosthodontic outcomes as well as overall patient reported outcome measures for modSLA (SLActive, Institut Straumann AG, Switzerland) and NGA (TiUltraNP, Nobel Biocare AG, Switzerland) dental implants.

Ultra-hydrophilic SLActive (modSLA) implants have been extensively studied in pre-clinical and clinical studies, demonstrating their pro-osteogenic nature and long-term maintenance of facial bone and aesthetics.

A novel multi-zone novel gradient anodized (NGA) hydrophilic surface (TiUltra) has recently been introduced to clinical practice. Pre-clinical studies have demonstrated that the smoother coronal aspect achieved stable soft tissue adhesion.

In clinical practice, prosthetically driven implant placement, particularly in the anterior maxilla, may result in a buccal dehiscence that is commonly treated with guided bone regeneration (GBR). Currently no studies have been published investigating differences between these commercially available implant surfaces (modSLA, NGA).

This prospective, single centre randomised clinical trial will recruit 39 patients who require a single tooth extraction in the anterior maxilla for a Type IIc implant placement.

Patients enrolled in the study will be allocated to one of three implant groups:

• Group 1: NGA Implant (NobelActive TiUltraNP, Nobel Biocare AG, Switzerland)
• Group 2: BLX implant (BLX) modSLA Surface (BLX, SLActive, Roxolid, Institut Straumann AG, Switzerland)
• Group 3: TLX implant (TLX) modSLA Surface (TLX, SLActive, Roxolid, Institut Straumann AG, Switzerland).

This study aims to characterise the stability of crestal bone levels one year after loading, the associated aesthetic outcomes, immunological response, prosthodontic outcomes as well as overall patient reported outcome measures.

Inclusion Criteria:

• Age: over 18 years old,
• Gender: male and female.
• Patient must be able and willing to follow study procedures and instructions and have capacity to provide informed consent.
• Patient must require tooth extraction of a maxillary first premolar or single-rooted anterior tooth as the result of caries, endodontic failure or trauma
• The extraction site must have adjacent teeth present.
• Adjacent teeth with no evidence of interdental bone loss

Exclusion Criteria:

• Systemic disease that can interfere with dental implant therapy (e.g. uncontrolled diabetes)
• 2 adjacent teeth requiring extraction
• Greater than one wall of the socket missing - assessed at time of extraction
• Any contraindications for oral surgical procedures
• Any known systemic disease affecting bone metabolism (e.g. Cushing's syndrome, Crohn's disease, rheumatoid arthritis, osteoporosis, diabetes type I and uncontrolled diabetes type II), systemic infections or recent surgical procedures within 30 days of study initiation;
• Chronic treatment (i.e., 2 weeks or more) with any medication known to affect oral status (e.g., phenytoin, dihydropyridine, calcium antagonists and cyclosporine) or bone metabolism (e.g. bisphosphonates, hormone replacement therapy, immunosuppressants) within 1 month before baseline visit;
• HIV or viral hepatitis;
• Physical handicaps that would interfere with the ability to perform adequate oral hygiene;
• History of local irradiation therapy in the head-neck region
• Mucosal diseases (e.g. erosive lichen planus)
• Current untreated periodontitis or gingivitis. In particular probing depths of >4mm on one of the teeth immediately adjacent to the extraction site
• Untreated acute endodontic lesions
• Current smokers (have smoked within 3 months of study onset)
• Any known systemic disease affecting bone metabolism (e.g. Cushing's syndrome, Crohn's disease, rheumatoid arthritis, osteoporosis, diabetes type I and uncontrolled diabetes type II), systemic infections or recent surgical procedures within 30 days of study initiation;
• Self-reported alcoholism or chronic drug abuse;
• Patients suffering from a known psychological disorder or with limited mental capacity or language skills such that study information could not be understood,
• Non-compliant patients, vulnerable individuals or those unable to understand written or verbal communication and give consent.
• Pregnant or breastfeeding patients
• Involvement in current research or recent involvement in any research prior to recruitment
• Full-mouth bleeding (BOP) and plaque (PI) scores >30% or sites with periodontal pocket depth >5 mm at the completion of the pre-treatment phase.