Malocclusion Characteristics as Risk Factors for Temporomandibular Disorders: Lessons Learned from a Meta-Analysis

Table 1

Assessment of retrieved full-text articles for inclusion.

	Sample size	Selection methods	Measurement methods sufficient	Method error	Examiner blinding present	Adequate data for analysis	Confounders present	Stated definition of TMD	Inclusion
Fantoni et al., 2010 [9]		CC; only women	Y	Cases/controls were only matched in age and gender	Possible	Y	Unlikely	RDC/TMD Axis 1 group 1	Y
Landi et al., 2004 [10]		CC; only women	Y	Cases/controls were only matched in gender	Unlikely	Y	Unclear	RDC/TMD Axis 1 group 1	Y
Marinho et al., 2009 [11]		CC; M/F adults	Y	Cases/controls were only matched in age	Possible	Y	Cases were 3/4 female; controls were 1/2 female	RDC/TMD Axis 1	Y
Marklund and Wänman, 2010 [12]		Cohort converted to CC at follow-up; M/F adults	Y	Intended cohort study later converted to a case/control study; therefore no effort to match cases/controls existed	Y	Y	No history of orthodontic treatment was assessed; dropouts were not accounted for	2-year persistent jaw muscle (JM) signs OR symptoms; assisted by RDC/TMD Axis 1 group 1a and group 3a	Y
Mohlin et al., 2004 [13]		Cohort converted to CC at follow-up; M/F adults	Y	Intended cohort study later converted to a case/control study; therefore no effort to match cases/controls with respect to characteristics other than age (all subjects were 19 at follow-up) existed	Possible	Y	“Previous history of orthodontic treatment was assessed,” but it is unsure how this information factored into analysis or sample selection; dropouts were not accounted for	CE using a function and muscle checklist	Y
Selaimen et al., 2007 [14]		CC; only women	Y	Cases/controls were only matched in age and gender	Y	Y	No history of orthodontic treatment was assessed	RDC/TMD	Y
Costa et al., 2012 [15]		CC; M/F adults	Y	Cases/controls were unmatched; TMD diagnosis not clinical	Unlikely	Y	Cases were 88% female and older; controls were 64% female and younger	10-item questionnaire related to signs and symptoms of TMD; interview not CE	N
Gesch et al., 2004 [16]		CS population study; M/F adults	Y	Unlikely to find serious methodology error	Y	N	No history of orthodontic treatment was assessed	TMD Guidelines of the Academy of Orofacial Pain; ≥2 symptoms needed on CE	N
Pahkala and Qvarnström, 2004 [17]		Cohort converted to CC at follow-up; M/F adolescents	Y	TMD definition inadequate; lack of inclusion/exclusion criteria for cases/controls; and unlikely that cases/controls were matched by characteristics other than age	Unlikely	N	Significant dropouts at final follow-up; no history of orthodontic treatment was assessed	“TMD signs” = functional, muscle tenderness	N
Turasi et al., 2007 [18]		Matched cohort; M/F adults	Y	Small sample size (33 cases/33 controls)	Unlikely	N	Unlikely	“Clinical [13] detectable TMD”	N

CC = case control; CE = clinical examination; CS = cross-sectional.