Additional File 1 Summary of Primary and Additional Outcomes of All Included Studies

Additional file 1 – Summary of primary and additional outcomes of all included studies CS = cross-sectional study; LT = longitudinal study; CO = cohort study; VA = validation. 1, 2 same numbers indicate same sample. First author, Population/sample Subject of the study Main outcomes concerning Other outcomes/conclusions year n (% females) missing teeth

OHIP-49 (Oral Health Impact Profile)

Bae, 2007VA Korean elderly OHIP validation for Number of missing teeth Perceived treatment need also [22] elderly associated with OHRQoL associated with OHRQoL n =128 (51) impairment. impairment.

Hassel, German Dental and non-dental No difference in OHRQoL Fewer teeth in static occlusion 2006CS [23] institutionalized factors on OHRQoL between dentate and associated with OHRQoL impairment elderly of institutionalized edentulous subject.s (bivariate analysis). elderly n = 159 (81) Non-dental factors had a striking effect on OHRQoL. The model with variables education, general pain status, denture retention, age of denture and kind of denture, explained 34% of the variance in OHIP total scores.

Ide, 2004VA Japanese employees OHIP validation for Number of missing teeth Outcome independent of gender, age, [12] young and middle- associated with OHRQoL and denture wearing. n = 6079 (25) aged adults impairment.

Locker, Canadian older Clinical and Number of missing teeth Non-dental factors (general health, 1994LT [29] adults subjective indicators associated with OHRQoL life stress, dental insurance, of oral health status impairment. household income and age) explained n = 312 (54) and OHRQoL almost as much variance in OHIP scores as the number of missing teeth (14, respectively 18%).

Mason, British middle aged Risk factors, Number of retained teeth OHRQoL in men mostly explained 2006CO [30] adults lifecourse and more impact on OHRQoL in by ‘early-life’ factors. OHRQoL woman; impact for men n = 281 (57) almost absent.

Walter, Canadian rural Clinical and socio- Number of present natural Missing anterior teeth associated with 2007CS [48] adults demographic variables teeth was not a significant OHRQoL impairment. and OHRQoL variable in OHRQoL. n = 140 (64) OHRQoL positively related to molar pairs occluding, anterior pairs occluding, premolar pairs occluding and total number of occluding pairs.

Gender and normative endodontic treatment need also effected OHRQoL.

OHIP-14 (Oral Health Impact Profile short version) de Oliveira, Brazilian Validation of the Tooth loss associated with Perceived and normative dental 2005VA [39] postpartum women Brazilian OHIP-14 OHRQoL impairmen.t treatment needs, self-rating oral health, pattern of dental attendance n = 504 (100) and untreated dental caries also associated with OHRQoL impairment.

Ekanayake, Sinhalese elderly Oral health status and Weak association between Wearing dentures and halitosis were 2004CS [10] oral impacts in elderly number of missing teeth and significant predictors of OHRQoL n = 235 (60) OHRQoL impairment. impairment.

Lahti, 2008CS Finish adults aged Prevalence and Subjects with more missing Subjects with 20 or more teeth [25] over 30 yrs severity of oral health teeth have higher prevalence wearing RPD more likely to report impacts of, and more severe impact oral impacts than those with 20 or n = 5897 (53) on OHRQoL. more teeth without RPD. Young subjects with low educational level had higher and more impacts.

Lawrence, 32-year old New Dental and non-dental Tooth loss associated with Clinical oral health status indicators 2008CO [26] Zealanders factors on OHRQoL OHRQoL impairment. associated with OHRQoL in a birth cohort impairment, independent of gender n = 924 (49) and SES.

Mariño, Australian older Self-reported and Number of missing teeth Male subjects, subjects with fewer 2008CS [4] adult migrants clinically determined associated with OHRQoL reported oral health treatment need oral health status impairment. and subjects that did not need to sip n = 603 (64) aspredictors of liquid to swallow food had less OHRQoL OHRQoL impairment.

Pallegredara, Sinhalese elderly Tooth loss, denture Number of missing teeth Anterior spaces more impact on 2008CS [40] status and OHRQoL most significant predictor of OHRQoL than posterior spaces. n = 630 (54) OHRQoL.