Techniques to Guide the Mandible to Centric Relation- A Systematic Review

Abstract

Introduction: Centric Relation (CR) is the only physiological position which is repeatable, recordable and reproducible for prosthodontic rehabilitation. A missed CR can give rise to faulty occlusal relationships leading to a life time of trauma to the temporomandibular joints. Literature has various methods outlined to locate and record the CR but it’s confusing as to which method is best suited to take the condyles into CR position. Hence, this systematic review was conducted to find an answer to this very question. Aim: To find a reliable clinical technique to guide the mandible to a recordable, repeatable and reproducible CR position. Materials and Methods: The present systematic review was conducted from July 2019 to October 2019 at School of Dental Sciences, KIMSDU, Maharashtra. A 20-year comprehensive literature review was undertaken aiming to arrive at a reliable and repeatable method to guide the mandible to CR following the Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) and Patient Intervention Comparison Outcome (PICO) guidelines to the highest possible extent. The research material was sifted through MEDLINE (PubMed) –{(“CR technique”) (MeSH terms) AND/OR (Retruded mandibular position”) (MeSH terms)}, Cochrane library “CR techniques” and Google Scholar “CR techniques OR Retruded mandibular position” search engines. Cochrane collaboration tool was used to assess the risk of bias for the Randomised Controlled Trial, Methodological I index for non RCTs (MINOR). Quality and strength of the existing evidence was appraised by both the authors through Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Results: Online database search was conducted from January 1998 to September 2019 resulting in a total of 950 articles being shortlisted. Post-screenings, using the exclusion criteria, nine articles of the total articles were reviewed. These were reviewed individually by both the authors and discussed for various techniques to guide the mandible to CR. The ultimate outcome of the review was that the clinicians are required to fall back on time tested models, scientifically sound and technically correct and uncomplicated to execute methods which have proven to yield the most excellent outcomes at zero or minimal cost. One such method is undoubtedly Dawson’s Bimanual Technique. Bimanual technique in supine position coupled with a simple anterior deprogrammer has consistently resulted in a physiological CR position that is recordable, repeatable and reproducible. Conclusion: The primary outcome of this systematic review is that Dawson’s bimanual manipulation technique is superior to other techniques; primarily when carried out in supine position.

Keywords

• centric occlusion
• condyle
• retruded mandibular position temporomandibular joints