Efficacy of Kinematic Parameters for Assessment of Temporomandibular Joint Function and Disfunction: A Systematic Review and Meta-Analysis

Abstract

The aim of this review was to answer the following PICO question: "Do TMJ kinematic parameters (intervention and comparison) show efficacy for assessment of mandibular function (Outcome) both in asymptomatic and TMD subjects? (Population)". PubMed, Scopus, Web of Science, Embase, Central databases were searched. The inclusion criteria were (1) performed on human, (2) English only, (3) on healthy, symptomatic or surgically altered TMJ, (4) measured dynamic kinematics of mandible or TMJ (5) with six degrees of freedom. To assess the Risk of Bias, the Joanna Briggs Institute tool for non-randomised clinical studies was employed. A pairwise meta-analysis was carried out using STATA v.17.0 (Stata). The heterogeneity was estimated using the Q value and the inconsistency index. Ninety-two articles were included in qualitative synthesis, nine studies in quantitative synthesis. The condylar inclination was significantly increased in female (effect size 0.03°, 95% CI: -0.06, 0.12, p = 0.00). Maximum mouth opening (MMO) was increased significantly in female population in comparison with males (effect size 0.65 millimetres (0.36, 1.66). Incisor displacement at MMO showed higher values for control groups compared with TMD subjects (overall effect size 0.16 millimetres (-0.37, 0.69). Evidence is still needed, considering the great variety of devices and parameters used for arthrokinematics. The present study suggests standardising outcomes, design, and population of the future studies in order to obtain more reliable and repeatable values.

Keywords: TMJ dysfunction; kinematics; motion analysis; temporomandibular joint; temporomandibular joint disorders.

Figure 1

PRISMA flow chart.

Figure 2

Forest plot for condylar inclination outcome.

Figure 3

Forest plot for different method employed to estimate the condylar inclination.

Figure 4

Condylar inclination subgroup analysis forest plot displays the study labels (id), the number of studies within each group (K), the plot of effect sizes and their CIs (plot), the values of effect sizes and their CIs (esci), and the p-values (p-value) of the corresponding significance tests. The between-group homogeneity test based on the Qb is reported for each subgroup analysis. For example, for subgroup analysis based on variable “Group”, there are two groups “test” and “control”. The test investigates whether the overall effect sizes corresponding to these two groups are the same. The results of this test are identical to those we would have obtained if we had specified subgroup (Group).

Figure 5

Forest plot for MMO outcome. The overall effect size was 0.65 (−0.36, 1.66). The highest weight was 27.01% with sample size N = 48 in males and N = 44 in females. The heterogeneity is I² = 90.12% which indicates, the studies were found to be highly heterogeneous in characteristics. The pooled effect has passed the line of no effect, hence there exists statistically significant difference between the studies in MMO outcome favouring females.

Figure 6

Subgroup analysis for MMO outcomes. The overall effect size was 0.65 (−0.36, 1.66). There is statistical significance between the type of studies included and its impact of results in MMO outcome. In addition, the method employed to record MMO outcome was statistically significant. Children and adult did not have significant values although the effect size varied i.e., child 0.31 (−1.10, 0.72) and adult 0.80 (−0.64, 2.23).

Figure 7

Galbraith Plot for MMO Outcome illustrating heterogeneity of the studies and detecting potential outliers. Two studies identified as an outlier.

Figure 8

Publication bias for MMO outcome.

Figure 9

Forest plot for IP-MMO outcome.

Figure 10

Publication Bias for IP-MMO outcome.

Figure 11

Galbraith plot for IP-MMO outcome.

Figure 12

Forest plot for horizontal angle outcome.

Figure 13

Publication bias for horizontal angle outcome.

Figure 14

Galbraith plot for horizontal angle outcome.

Figure 15

Forrest plot for sagittal angle outcome.

Figure 16

Funnel plot for sagittal angle outcome.

Figure 17

Galbraith plot for Sagittal angle outcome.