Table 2.
Summary of included articles and grading
| Study | Description | Justification for Grading | Grade |
|---|---|---|---|
| Qudeimat and Sasa (2015) | Controlled Clinical trial Compared B&L and C&L SMs 52 months length Loss of primary first molars |
Well conducted study, risk of bias from non randomised allocation, however this was due to ethical reasons and was in favour of the control group. The very large and significant difference in the magnitude of effect of the study increased the quality grading to ‘High’ | High |
| Garg et al. (2014) | Split Mouth RCT Compared GFRCR placed with rubber dam and B&L SMs 6 month observation Loss of a primary first molar |
Well reported study, however risk of bias through poor description of randomisation method and risk of imprecision through short length of observation | Moderate |
| Gulec et al. (2014) | Case Series of a commercially available DB SM (the E-Z SM) used following loss of one or two primary molars 20 month observation |
Well reported, limited in quality due to nature of study | Low |
| Nidhi et al. (2012) | Split Mouth RCT Compared GFRCR placed with rubber dam and B&L SMs 5 month observation Loss of a primary first or second molar |
No information on the method of randomisation and short observation period therefore downgraded due to risk of bias and imprecision | Moderate |
| Tunc et al. (2012) | RCT Compared B&L, DB and GFRCR SMs placed without Rubber Dam 12 month observation Loss of primary first or second molar |
Method of randomisation not described, small sample sizes, confidence intervals not provided for findings, therefore downgraded to Moderate | Moderate |
| Owais et al. (2011) | RCT Compared space changes between LLAs constructed with 0.9 mm and 1.25 mm wire and a control group with no SM Loss of one or both lower primary second molars after eruption of permanent incisors |
Well randomised, controlled and fully reported, findings consistent with other studies, directly relevant to PICO | High |
| Sasa et al. (2009) | Uncontrolled prospective study of B&L SMs 40 month follow up Loss of primary first molars |
Well conducted, well reported, long observation period, limited on quality due to lack of a control group | Low |
| Subaramaniam et al. (2008) | Split mouth RCT Compared GFRCR placed with rubber dam and B&L SMs 12 month observation Loss of primary first molars |
Method of randomisation not described, some reporting does not reflect the method therefore downgraded to moderate | Moderate |
| Fathian et al. (2007) | Retrospective reporting on treatment notes for all B&L, Nance and LLA SMs placed by a single practitioner over a 7 year period Loss of a first or second primary molar. Failed appliances re-included as new appliances |
Directly relevant to the PICO however limited in quality due to inherent low quality of observational studies | Low |
| Moore and Kennedy (2006) | Retrospective reporting on treatment notes for Nance and LLA SMs placed by two different practitioners over 7 year period SMs used to hold the leeway space, with and without premature loss of a primary molar |
Some indirectness although this was not severe, limited in quality due to inherent low quality of observational studies | Low |
| Yilmaz et al. (2006) | Case studies of DB SM bonded with 12 month follow up. Window cut through a PMC exposing buccal enamel surface to which a DB SM was bonded. Premature loss of primary first or second molars | No control group, no criteria for assessing failures, and incomplete data reported; severe risk of bias so downgraded | Very low |
| Tulunoglu et al. (2005) | Described itself as a retrospective study, however the description of its method is prospective Unable to Distinguish types of SMs used |
Very poorly reported, Method unclear and vague, high ‘lost to follow up rate’, severe risk of bias, findings were not included in the outcome analysis | Very low |
| Kargul et al. (2005) | Case Studies of GFRCR SMs placed without rubber dam 12 month follow up |
Very little information and lack of data presented to justify findings or conclusions; severe risk of bias and imprecision | Very low |
| Kirzioglu and Erturk (2004) | Case Studies of GFRCR SMs placed without rubber dam 24 month observation period |
Limited in quality due to inherent low quality of observational studies, some indirectness however data presented clearly to identify those relevant to PICO Some incomplete outcome reporting but not at severe risk bias so not downgraded | Low |
| Simsek et al. (2004) | Case Studies of DB SMs 12–18 month follow up |
No clear inclusion criteria or predefined failure criteria and method unclear, no data presented to substantiate conclusions, failures of composite bonding were still included as successes; severe risk of bias, inconsistency and imprecision | Very low |
| Rajab (2002) | Prospective Cohort study 60 months duration Reporting on B&L, Nance, LLA and Removable SMs |
Some indirectness, unclear inclusion criteria, no confidence intervals provided and high loss to follow up (19.9%); therefore at risk of imprecision | Low |
| Brill (2002) | Case Studies over a 6 year period of crown retained DES SM Loss of a primary molar with no tooth distal to the space (one case after extraction of a permanent first molar) |
Risk of bias as one practitioner assessing, treating and publishing the report, lack of a control group and severe risk of bias, 43% still in use at the time of publication, no minimum observation period provided; severe risk of imprecision | Very low |
| Qudeimat and Fayle (1998) | Retrospective reporting on treatment notes of all patients who had SMs during a five year period at a dental hospital, reported on B&L, Nance, LLA and Removable SMs | Low quality due to study design, not downgraded further although some risk of inconsistency and indirectness as SMs not used exclusively for primary molar loss | Low |
| Baroni et al. (1994) | Described as an observational study of 53 months B&L SMs, Nance SMS and LLA SMs |
Incomplete reporting, no inclusion criteria and insufficient description of the method of this study to ascertain if it was retrospective or prospective, method unclear and vague; severe risk of bias and imprecision | Very low |
| Santos et al. (1993) | Case series of DB SMs Six months observation Loss of primary first or second molar |
Limited quality due to study type, some lack of detail in reporting however not severe risk of bias so not downgraded | Low |