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Trial registered on ANZCTR

Registration number
Ethics application status
Submitted, not yet approved
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Type of registration
Prospectively registered

Titles & IDs
Public title
The effects of grafting with dental biomaterials on the tooth-supporting tissues surrounding lower second molars following removal of impacted third molars in healthy young adults
Scientific title
Bio-Oss Collagen grafting and the periodontal attachment effects following extraction of mesioangular, impacted third molars in medically healthy and periodontally sound 18 - 35 year old adults.
Secondary ID [1] 300834 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Loss of periodontal attachment on distal aspect of mandibular second molar as a result of an impacted third molar 316722 0
Condition category
Condition code
Oral and Gastrointestinal 314966 314966 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon

Study type
Description of intervention(s) / exposure
Tooth extraction and ridge preservation will be performed by the specialist oral and maxillofacial surgeon (under local or general anaesthesia) using a minimally traumatic approached aimed to preserve an intact buccal bony cortex. If necessary, roots will be sectioned with a bur and removed separately to minimize damage to the bony cortex. Careful curettage of the socket will be performed to remove all bony and tooth debris and infective tissue and exposed tooth structure of the adjacent tooth will be debrided. It is anticipated that extracting both third molars will take approximately 45 minutes of surgical time. Once both third mandibular third molars have been removed, the surgeon will then open a sealed envelope indicating which side (left or right) is receiving the grafting procedure (test site) and which site is receiving no additional treatment (control site).

In test sites, the extraction socket will be grafted with Bio-Oss Collagen which will be firmly compacted and secured against the exposed root, cemento-enamel junction and approximately one millimetre above the junction. This will take approximately one minute of surgical time and the study intervention is completed at this time.

Both test and control sites will be closed by primary flap closure where possible and secured with sutures.

The surgeon will discuss post-operative antibiotic and analgesic therapy with each patient. Subjects will be instructed to avoid rinsing and spitting for the first twenty-four hours. Subjects will be advised to use zero-point two percent chlorhexidine mouth wash for rinsing twice daily and to avoid brushing directly on the surgical site for one week. Subjects will be advised to maintain a soft diet for two weeks. Patients will be reviewed in approximately two weeks (or similar timeframe as required by the surgeon) and sutures will be removed. Any incidence of postoperative complications will be recorded and can be compared between control and test groups.

Final clinical and radiographic measures will be taken six months after the surgery.
Intervention code [1] 317161 0
Treatment: Surgery
Intervention code [2] 317204 0
Treatment: Devices
Comparator / control treatment
The control treatment is no treatment. Both test and control sites will receive the clinically necessary extractions and primary flap closure as per the inclusion criteria. Experimentally, test sites are receiving grafting with Bio-Oss Collagen and control sites are receiving nothing.
Control group

Primary outcome [1] 323277 0
The primary outcome will be to compare the mean probing depths between test and control sites six months after healing. This will be assessed by periodontal probes.
Timepoint [1] 323277 0
6 months after the extractions
Secondary outcome [1] 381409 0
Bleeding on probing between test and control sites. This will be measured by probing the periodontal pockets and waiting 15 seconds. A scoring system of 1 (present) and 0 (absent) will be used to measure bleeding on probing
Timepoint [1] 381409 0
6 months after the extraction
Secondary outcome [2] 381410 0
radiographic distance between the cement-enamel junction and the alveolar crest on the distal aspect of the second molar. This will be measured by comparing data fr0m the pre-operative and post-operative cone beam CT scan
Timepoint [2] 381410 0
6 months after the extractions
Secondary outcome [3] 381411 0
Patient reported outcomes: measuring pain levels between test and control sites on the visual analogue scale
Timepoint [3] 381411 0
6 months after the extraction
Secondary outcome [4] 381546 0
patient reported outcomes: measuring patient level satisfaction on the patient satisfaction questionnaire.
Timepoint [4] 381546 0
6 months post-operatively

Key inclusion criteria
• Two unerupted mandibular third molars that are Class I or II, Position C on Pell and Gregory scale with a Horizontal or Mesioangular (up to 45 degrees) of the Winter classification21, 22

• Periodontal probing depths of 5mm or greater on the distal aspect of the mandibular second molar due to an impacted wisdom tooth
• Evidence of radiographic bone loss of more than 5mm from the cementoenamel junction to the crest of the alveolar bone on the distal aspect of the distal root of the adjacent second molar at time of initial examination due to an impacted wisdom tooth
• Able to tolerate extraction procedure: surgeon will determine this parameter
• Medically fit and well. Classified as American Society of Anaesthesiologist (ASA) Class I patient as a normal, healthy patient. (no medical illness e.g. diabetes, not smoking, low alcohol intake)
• Aged 18 – 35 years old
Minimum age
18 Years
Maximum age
35 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
• Impacted third molars that are disto-angular impacted or require extensive surgery
• Patient has a history of diagnosed periodontitis disease (more than 2mm of clinical attachment loss)
• Patient currently has periodontal disease in any aspect of the mouth except periodontal breakdown associated with impacted third molars (mandibular or maxillary)
• Patient has lost more than 2mm of clinical attachment due to non-periodontal reasons
• Pathology that requires more than just extraction and primary wound closure
• Plaque index of 40% or more (indicating poor oral hygiene)
• Patients unwilling to return for all periodontal review appointment

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Sealed opaque envelopes
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Simple randomisation using a randomisation table created by computer software (i.e. computerised sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
The clinical trial is a split mouth design. The same subject will have a test site and a control site.
Phase 4
Type of endpoint(s)
Statistical methods / analysis
Sample size calculations: Considering the primary outcome variable is post-operative periodontal probing depth, a mean difference of 1.5mm is considered significant. Using a standard deviation of 1.5mm and a confidence interval of 0.75mm, the sample size calculation was came to 16 sites per group. However, this assumes that the data will be normally distributed. To account for subject drop-outs and the chance that the data will not be normally distributed, we will target 32 sites per group. 

At the 6 month review, ANOVA tests will be used to compare means between and within test and control groups at the beginning and end of the trial.

Recruitment status
Not yet recruiting
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment postcode(s) [1] 29681 0
4305 - Ipswich
Recruitment postcode(s) [2] 29682 0
4122 - Mount Gravatt
Recruitment postcode(s) [3] 29684 0
4064 - Milton

Funding & Sponsors
Funding source category [1] 305292 0
Commercial sector/Industry
Name [1] 305292 0
Geitslich Pharma Australia
Address [1] 305292 0
821 Pacific Hwy, Chatswood NSW 2067
Country [1] 305292 0
Primary sponsor type
The University Of Queensland
School of Dentistry
Oral Health Centre Herston
288 Herston Rd,
Herston QLD 4006
Secondary sponsor category [1] 305652 0
Name [1] 305652 0
Address [1] 305652 0
Country [1] 305652 0

Ethics approval
Ethics application status
Submitted, not yet approved
Ethics committee name [1] 305630 0
Human Research Ethics Committee
Ethics committee address [1] 305630 0
National Health and Medical Research Council
Human Research Ethics Committee
16 Marcus Clarke St,
Canberra ACT 2601
Ethics committee country [1] 305630 0
Date submitted for ethics approval [1] 305630 0
Approval date [1] 305630 0
Ethics approval number [1] 305630 0

Brief summary
Impacted mandibular third molars can cause extensive damage to the bone and supporting structures (known as the periodontal attachment) surrounding the adjacent second molar. This clinical trial is conducting research on the benefits of ridge preservation, also known as socket grafting, carried out at the time of extraction of an impacted mandibular third molar provides any additional periodontal attachment. In many cases after a tooth extraction, soft tissue and bone grows into the site to facilitate healing and the formation of periodontal tissue to support the adjacent second molar. However, in some cases the healing does not proceed as desired and there are inadequate amounts of periodontal attachment. This means that the bone and tissue support around the adjacent molar is compromised and the tooth has an increased risk of being lost prematurely.

Bone substitute materials have been widely used for socket grafting and periodontal regenerate procedures for more than 15 years. Geistlich Bio-Oss Collagen® supports the body’s own bone regenerative processes extremely effectively and help guide hard tissue formation following tooth extraction. Bio-Oss Collagen® consist of 90% Bio-Oss® with 10% porcine collagen. Bio-Oss® is derived from the bone of an Australian bovine herd around Melbourne. The bones are transported to Switzerland for treatment either by heat, chemicals or both to remove all organic components. Porcine collagen is added as part of this process to provide some dimensional stability. Bio-Oss Collagen® is made under a strictly controlled manufacturing process. Due to the great similarity to human tissue, these materials are optimally suited and widely used clinically to promote new bone formation and tissue healing in the human body.

Current treatment following an extraction involves healing by blood clot with or without placement of sutures to stabilize the blood clot. Recent evidence suggests that the application of Bio-Oss Collagen® might help assist the healing process to reform the desired levels of bone, gum and periodontal supporting tissue.

We are interested in whether socket grafting with Bio-Oss Collagen® will help bone, gum and periodontal tissue formation around the adjacent, remaining tooth compared to standard extraction protocols. This will result in a greater amount of periodontal tissue supporting the adjacent tooth and reduce the risk of premature tooth loss. We are particularly interested in healthy 18 – 35 years old subjects.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 101018 0
Dr Anthony Puljich
Address 101018 0
Periodontics Department, School of Dentistry
The University of Queensland
288 Herston Rd
Herston QLD 4006
Country 101018 0
Phone 101018 0
+61 438870271
Fax 101018 0
Email 101018 0
Contact person for public queries
Name 101019 0
Dr Anthony Puljich
Address 101019 0
Periodontics Department, School of Dentistry
The University of Queensland
288 Herston Rd
Herston QLD 4006
Country 101019 0
Phone 101019 0
+61 438870271
Fax 101019 0
Email 101019 0
Contact person for scientific queries
Name 101020 0
Dr Anthony Puljich
Address 101020 0
Periodontics Department, School of Dentistry
The University of Queensland
288 Herston Rd
Herston QLD 4006
Country 101020 0
Phone 101020 0
+61 438870271
Fax 101020 0
Email 101020 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
What data in particular will be shared?
all of the individual participant data collected during the trial, after de-identification
When will data be available (start and end dates)?
Immediately following publication, for 6 months
Available to whom?
only researchers who provide a methodologically sound proposal
Available for what types of analyses?
to achieve the aims in the approved proposal and for IPD meta-analyses
How or where can data be obtained?
access subject to approvals by Principal Investigator (email:
What supporting documents are/will be available?
No other documents available
Summary results
No Results