Evaluation of the Prevalence Rate and Related Risk Factors of Ridge Preservation

Treated by dental implant is a well document and popular therapy nowadays. Placement of a dental implant in an ideal three-dimensional position is critical in achieving a predictable long-term success. However, healing of an extraction socket involves bone remodeling, which inevitably leads to atrophic changes of the alveolar ridge. Studies have shown that most of the resorption occurs during the first 3 months of healing, although dimensional changes can be observed up to 1 year after tooth extraction, resulting in approximately 50% reduction of the bucco-lingual dimension of the alveolar ridge, mainly due to the resorption of the bundle bone plate.

Therefore, the timing of implant placement in extraction sockets can influence the surgery operability and treatment period of time. The classifications of timing of implant placement in extraction sockets as following: Type I: immediate implant placement: implant placement immediately following tooth extraction and as part of the same surgical procedure. Type II: early implant placement: surgery after complete soft tissue coverage of the socket (typically 4~8 weeks).

Type III: early implant placement: implant surgery after substantial clinical and/or radiographic bone fill of the socket (typically 12~16 weeks). Type IV: late implant placement: surgery at healed site (typically more than 16 weeks). Considering of technique sensitivity and treatment time consuming, early implant placement is the most acceptable clinically.

Many techniques have been developed to maintain the architecture of residual alveolar ridges and regenerative techniques for socket preservation is one of them. This procedure has been widely tested in controlled and uncontrolled studies with various materials and clinical approaches. However, this procedure may require longer treatment period compare to conventional or early implant placement protocol. Meanwhile, there is no study revealed how often and when does socket preservation need to prevent the residual ridge deformity in our daily clinical practice. The aim of the study is try to retrospectively find out the possible advantages and percentage of ridge preservation after tooth extraction in order to understand whether the socket preservation technique is necessary after tooth extraction, and the possible factors which might affect the clinical decision-making.

Study Overview

• Status: Completed
• Conditions: Dental Implants
• Intervention / Treatment: Procedure: implant can be placed or not

Detailed Description

Background:

The alveolar process is a tooth-dependent tissue that develops in conjunction with the eruption of the teeth. The tooth is anchored to the jaws via the bundle bone into which the periodontal ligament fibers invest. Subsequent to the removal of the tooth, the alveolar process will undergo atrophy. The dynamics and magnitude of these changes have been investigated in the dog model as well as in humans. Most of the resorption occurs during the first 3 months of healing, although dimensional changes can be observed up to 1 year after tooth extraction, resulting in approximately 50% reduction of the bucco-lingual dimension of the alveolar ridge, mainly due to the resorption of the bundle bone plate. Some studies showed that significant loss of tissue contour occurs during the first month after tooth extraction, averaging 3~5mm in width at 6 months. As a result, a residual ridge is often inadequate for ideal implant placement, which creating a clinical challenge for the placement of a dental implant in an ideal position. However, placement of a dental implant in an ideal three-dimensional position is critical in achieving a predictable functional and esthetic restoration.

Therefore, the timing of implant placement in extraction sockets can influence the surgery operability and treatment period of time. The classifications of timing of implant placement in extraction sockets as following: Type I: immediate implant placement: implant placement immediately following tooth extraction and as part of the same surgical procedure. Type II: early implant placement: surgery after complete soft tissue coverage of the socket (typically 4~8 weeks).Type III: early implant placement: implant surgery after substantial clinical and/or radiographic bone fill of the socket (typically 12~16 weeks). Type IV: late implant placement: surgery at healed site (typically more than 16 weeks). Considering of technique sensitivity and treatment time consuming, early implant placement is the most acceptable clinically. However, different treatment strategies may be applied because of the vary amounts of resorption after tooth extraction.

Some of the extraction sockets will heal completely and the implant can be placed in an ideal position 3 months after tooth extraction. Others may require adjunctive surgical procedures (like guided bone regeneration, GBR) during the implant surgery. In some cases, with severe bone resorption after tooth extraction, staged approach for implant placement is recommended due to lack of sufficient bone volume, which is the most time consuming and expensive treatment method.

In order to avoid this situation, some surgical procedures have been described to prevent alveolar ridge collapsing after tooth extraction, including regenerative techniques for socket preservation and immediate implant placement after tooth extraction. The socket preservation technique has been widely tested in controlled and uncontrolled studies with various materials and clinical approaches. However, this may require longer treatment period compare to early implant placement protocol and so far, there is no study revealed how often and when does socket preservation need to prevent the residual ridge deformity in our daily clinical practice.

Purpose:

The purpose of this study is to evaluate:

1. How often do the clinical cases require ridge preservation than early implant placement protocol?
2. Which factors may influence the clinical decision?

Hypothesis:

Ridge preservation is better than early implant placement protocol.

Importance:

Help the clinician to make a more precise decision-making.

• Study Type: Observational
• Enrollment (Actual): 133

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Patients who plan to have single implant surgery from July 2009 to August 2015 were included in this study.

Description

Inclusion Criteria:

• periapical film at the time of tooth extraction
• implant surgery was scheduled within 4 months after tooth extraction.

Exclusion Criteria:

- who cannot identify the reason for tooth extraction or unclear periapical film

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Group 1; Patient who received an implant after surgery.	Procedure: implant can be placed or not; the possibility of receiving dental implants
Group 2; Patient who didn't receive an implant due to insufficient bone volume or implant primary stability for implant placement.	Procedure: implant can be placed or not; the possibility of receiving dental implants

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
reason for tooth extraction	due to caries, periodontal disease, tooth fracture, residual root, endodontic failure	at the day of implant surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Radiographic analysis	with or without apical lesion and with or without marginal bone loss	at the day of implant surgery

Collaborators and Investigators

• Sponsor: Chimei Medical Center
• Investigators: Principal Investigator: CHUNJUNG CHEN, MS, ChiMei Medical Center

Publications and helpful links

General Publications

• Hammerle CH, Araujo MG, Simion M; Osteology Consensus Group 2011. Evidence-based knowledge on the biology and treatment of extraction sockets. Clin Oral Implants Res. 2012 Feb;23 Suppl 5:80-2. doi: 10.1111/j.1600-0501.2011.02370.x. Erratum In: Clin Oral Implants Res. 2012 May;23(5):641.
• Araujo MG, Lindhe J. Dimensional ridge alterations following tooth extraction. An experimental study in the dog. J Clin Periodontol. 2005 Feb;32(2):212-8. doi: 10.1111/j.1600-051X.2005.00642.x.
• Cardaropoli G, Araujo M, Lindhe J. Dynamics of bone tissue formation in tooth extraction sites. An experimental study in dogs. J Clin Periodontol. 2003 Sep;30(9):809-18. doi: 10.1034/j.1600-051x.2003.00366.x.
• Cardaropoli G, Araujo M, Hayacibara R, Sukekava F, Lindhe J. Healing of extraction sockets and surgically produced - augmented and non-augmented - defects in the alveolar ridge. An experimental study in the dog. J Clin Periodontol. 2005 May;32(5):435-40. doi: 10.1111/j.1600-051X.2005.00692.x.
• Buser D, Chappuis V, Belser UC, Chen S. Implant placement post extraction in esthetic single tooth sites: when immediate, when early, when late? Periodontol 2000. 2017 Feb;73(1):84-102. doi: 10.1111/prd.12170.
• Ahn JJ, Shin HI. Bone tissue formation in extraction sockets from sites with advanced periodontal disease: a histomorphometric study in humans. Int J Oral Maxillofac Implants. 2008 Nov-Dec;23(6):1133-8.

Study record dates

Study Major Dates

• Study Start (Actual): April 10, 2014
• Primary Completion (Actual): January 3, 2018
• Study Completion (Actual): March 31, 2019

Study Registration Dates

• First Submitted: December 16, 2024
• First Submitted That Met QC Criteria: December 16, 2024
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 19, 2024
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: alveolar ridge preservation; Early implant placement
• Other Study ID Numbers: 1 0 3 0 3 - 0 0 5

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No