Relevance of Variations in the Opposing Dentition for the Functionality of Fixed and Removable Partial Dentures: A Systematic Review

Table 3

Quality of studies and publications.

Study	Random group assignment	Patient recruitment	<20% drop-outs/reasons given	Age of dentures^a	Consistency of data within publication	Presentation of results	Biometric quality^b
Randomized controlled trials
Budtz-Jørgensen and Isidor, 1990 [12]	Unclear	Consecutive	yes/yes	Homogenous	Yes	Complete	Minor flaws^c
Prospective interventional studies
Balshi et al., 1996 [13]	—	Consecutive	No drop-outs^d	Homogeneous	Yes	Incomplete	Minor flaws
Carlson and Yontchev, 1996 [14]	—	Unclear	No/yes	Inhomogeneous	Yes	Complete	Major flaws
Esquivel-Upshaw et al., 2008 [15]	—	Unclear	No drop-outs^d	Homogeneous	Yes	Incomplete	Minor flaws
Romeo et al., 2003 [16]	—	Consecutive	No drop-outs^d	Inhomogeneous	Yes	Incomplete	Major flaws
Ueda et al., 1993 [17]	—	Consecutive	No drop-outs^d	Inhomogeneous	Yes	Incomplete	Major flaws
Wayler et al., 1984 [18]	—	Unclear	Yes/no	n/a	No	Incomplete	Major flaws
Retrospective interventional studies
Randow et al., 1986 [19]	—	Unclear	Yes/no	Homogeneous	Yes	Incomplete	Major flaws
Studer et al., 1998 [20]	—	Consecutive	No/yes	Inhomogeneous	Yes	Incomplete	Major flaws
Yli-Urpo et al., 1985 [21]	—	Consecutive	No drop-outs^d	Inhomogeneous	No	Incomplete	Major flaws
Cross-sectional studies (questionnaires)^e
Frank et al., 1998 [22]	—	Unclear	—^f	Inhomogeneous	Yes	Incomplete	Major flaws
Hummel et al., 2002 [23]	—	Cross-sectional	—^f	n/a	Yes	Incomplete	Major flaws
Lassila et al., 1985 [24]	—	Unclear	—^f	Inhomogeneous	Yes	Incomplete	Major flaws
Liedberg et al., 2005 [25]	—	Cohort study	—^f	Inhomogeneous	Yes	Incomplete	Major flaws
Ow et al., 1997 [26]	—	Random sample	—^f	n/a	Yes	Incomplete	Major flaws
Tuominen et al., 1989 [27]	—	Random sample	—^f	n/a	Yes	Incomplete	Major flaws
Vallittu et al.,1993 [28]	—	Unclear	—^f	n/a	No	Incomplete	Major flaws

^aThe homogeneity or inhomogeneity of the age of the prosthesis as a qualitative statement of the authors of the report refers to the range, where it is stated.
^bThe biometric quality concerns the aspects of the study that are linked to the question, not the whole of the study as such.
^cThe assignment was done on the basis of X-ray adjusting for other patient characteristics, and therefore the biometric quality was affected.
^dNo drop-outs were observed in the study, irrespective of whether they occurred.
^eThe approach with one-time inquiries without followup is similar to a cross-sectional design.
^fThe studies do not give response rates for one-time inquiries.
n/a: not available.