Lateral Ridge Augmentation Around Implants

The rehabilitation of dentoalveolar defects and tooth loss has seen remarkable advancements over time. Extraction of tooth leads to reduction in physiologic dimension of bone and it is imperative to evaluate the site before implant placement. To overcome the loss of volume and to avoid complications, procedures to restore the resorbed alveolar bones prior to or during implant placement are usually performed.

Lateral bone augmentation procedures with guided bone regeneration (GBR) are well documented in the literature with predictable results. It generally involves bone substitute xenograft and bioresorbable membrane combined with implant placement in single stage procedure or separately in two- stage procedure. As the search for better and improved materials continues, a porcine derived ribose cross-linked volumising collagen matrix (VCMX) based on GLYMATRIX® technology has been introduced which showed benefits over the conventional membranes in terms of simplified procedure, degradation, membrane exposure and healing. The collagen scaffold has been reportedly used as a core material for guided bone regeneration, when there is sufficient bone to place an implant but a horizontal defect is present in the crestal ridge. As part of augmentation VCMX is designed to expand and ossify during healing. The advantage of the material is that when placed in one or two layers, it may eliminate the use of bone substitute or connective tissue graft thus simplifying the augmentation procedure. In addition, adding a bone substitute is a valid option based on indication.

In the quest of better material and simplified procedures, few authors have performed case studies based on application of VCMX for guided bone regeneration around dental implants and has shown promising results. However, there are no controlled clinical trials on application of VCMX for lateral ridge augmentation. Thus, the present study aims to assess the efficiency of VCMX compared to resorbable collagen membrane (RCM) and bone graft (BG) for lateral ridge augmentation around implants through a well designed, controlled clinical trial.

Source of data Patient visiting the Outpatient Section of the Department of Periodontology, Krishnadevaraya College of Dental Sciences and Hospital for replacement of lost teeth will be screened and randomly recruited for the study as per inclusion and exclusion criteria. The eligible subjects will be informed of the nature and benefits of the participation of the study and a written signed consent will be obtained.

Method of collection of data Sample Size The study would be a prospective, randomized controlled clinical trial. A sample size of 28 subjects with equal number of males and females who are eligible as per the inclusion criteria, belonging to 20 - 50 years of age group would be considered for the study. Sample size is calculated using online software (OpenEpi) Open Source Epidemiologic Statistics for Public Health, Version 3.01. Estimation is done considering a similar previous study to acquire 80% power and 5% type 1 error in power calculation.

Eligibility Criteria:
Inclusion Criteria:

1. Cooperative patients willing to participate in the study belonging to 20-50 years of age group
2. Patients indicated for implant placement
3. Based on SAC classification (Straight forward, Advanced, Complex), if the bone defect has at least two walls intact and implant placement is possible within the confines of ridge.10 In the present study, subjects belonging to Advanced category i.e., where simultaneous guided bone regeneration and implant placement is possible it would be considered.
4. Full mouth plaque score (FMPS) \< 20 %, Full mouth bleeding score (FMBS) \< 20 %.11
5. Ability to comply with the study related procedures such as exercising good oral hygiene and attending all follow-up examinations.
6. Ability to fully understand the nature of the proposed surgery and ability to sign the informed consent form.

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Exclusion Criteria:

1. Smokers
2. Probing depth \>4 mm
3. General contraindications for dental and/or surgical treatment
4. History of malignancy, radiotherapy, or chemotherapy for malignancy within the past 5 yrs
5. Pregnancy or breast feeding
6. Previous and concurrent medication affecting mucosal healing in general (e.g. steroids, large doses of anti-inflammatory drugs)
7. History of any allergic diseases -