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dental implants have been used in edentulous jaws to improve the retention and 
 stability of complete dentures .
attachment to the implants improves the stability 
 and function of the prostheses and increases patient satisfaction [ 1 - 4 ] . 

the implant connection also improves neuromuscular activity and adaptation and thereby 
 substantially improves masticatory function in edentulous patients [ 5 - 12 ] . 

implant treatment nearly doubles maximum bite forces compared with those achieved 
 with conventional complete dentures , and jaw muscles are used in a more efficient 
 way .
quality of life is affected in some way by oral health in the majority of people 
 [ 14 - 16 ] .
the 
 type and quality of prosthetic constructions , and nowadays more often implant - supported 
 prostheses , can be considered one aspect of oral health in elderly patients .
the 
 oral health impact profile index ( ohip-14 )  
 has been used as a shortened 14-item questionnaire to evaluate the impact of oral 
 health on the quality of life .
the index measures people 's perception of the social 
 impact of oral disorders on their well - being .
the ohip-14 captures only negative 
 impacts , whereas some other oral health - dependent quality of life instruments capture 
 both positive and negative impacts .
however , the ohip is the most frequently used 
 and best - documented instrument nowadays . 
 
the aim of our retrospective study was to gather information about the outcome 
 of treatment with implant - supported mandibular overdentures from the patients ' perceptions 
 by using the oral health impact profile index ( ohip-14 ) and to compare the attachment 
 systems used .
the research hypothesis was that implant connection in complete dentures 
 results in a favourable assessment of patients ' oral health - related quality of life .
altogether 112 patients treated with implant - supported mandibular overdentures 
 between 1985 and 2004 were invited to the follow - up . 

patients were referred to specialist care to the department of oral and maxillofacial 
 surgery in oulu university hospital being very demanding cases .
main indications 
 for implant treatment of these patients were severe retention problems of conventional 
 prostheses , recurrent mucosal pain and sore spots and problems with chewing related 
 to advanced alveolar bone resorption . the number of patients who took no contact and did not attend was 22 .
fourteen 
 patients had no possibility to come or said they did n't want to come and 18 patients 
 had died . in all , 58 ( 51.8% ) of the invited patients 46 female and 12 male ) attended 
 the examination ; 33/58 of the patients were treated during 1985 - 1994 and 25/58 
 during 1995 - 2004 .
there were 6 persons with 1 missing answer and 2 persons with more than 2 missing 
 answers .
the mean age of the patients examined was 55.2 years ( range 37 to 78 ) at the 
 time of the implantation procedure and 69 years ( range 56 to 90 ) at the time of 
 the follow - up , the mean follow - up time was 13.7 years ( range 3.3 to 21.9 ) .
the total number of implants installed and still in use was 197 ( average number 
 3 implants/ overdenture , range 2 to 4 ) , mean length 12 mm ( range 8 to 21 mm ) .
there 
 were altogether 48 overdentures with a bar connection and 10 with a ball connection . 

fifty - three patients had a conventional complete denture in the opposite jaw , 2 
 patients had an implant - retained overdenture , 1 patient had an implant - supported 
 fixed partial denture , 1 patient had a removable partial denture and 1 patient had 
 his own teeth .
the questionnaire ( ohip-14 ) was filled in by the patients before 
 the clinical examination .
every 7 dimension includes two items , yielding altogether 14 ( ohip 1 - 14 ) .
the 
 seven dimensions are functional limitation , physical pain , psychological discomfort , 
 physical disability , psychological disability , social disability and handicap .
the 
 five categories of response for each item are never (= 0 ) , hardly ever (= 1 ) , occasionally 
 (= 2 ) , fairly often (= 3 ) and very often (= 4 ) .
higher ohip scores indicate worse , 
 and lower ohip scores indicate better oral health - related quality of life .  
this study of 58 patients was approved by the ethical committee of the northern 
 ostrobothnia hospital district .
the average values for the ohip-14 were calculated using non - missing score values 
 and the results were analyzed using anova and student 's t - test .
spss software ( spss , 
 version 16.0 , spss , chicago , il , usa ) was used to perform the statistical analyses 
 of the data . a significant level of p < 0.05 was used .
the frequencies of the seven different ohip dimensions are presented in 
 figure 1a - g. the distribution of the patient 's 
 responses was uniform in all seven ohip-14 dimensions except in the dimension of 
 ' physical pain ' , where fewer ' never ' answers i.e. more complaints were reported 
 by the patients ( figure 1b ) . according to the questionnaire , it was seen that most of the patients were satisfied 
 with their oral health and prostheses and there were no statistically significant 
 differences between women and men ( p > 0.05 ) .
patients ' perceptions of the social impact of oral disorders on their well - being 
 according to the questionnaire ( ohip-14 ) .
the five categories of response for each 
 item are never (= 0 ) , hardly ever (= 1 ) , occasionally (= 2 ) , fairly often (= 3 ) 
 and very often (= 4 ) . a = functional limitation ( ' trouble pronouncing words because 
 of problems with teeth , mouth or dentures ' ( ohip 1 ) and ' sense of taste has worsened 
 because of problems with teeth , mouth or dentures ' ( ohip 2 ) ) .
b = physical pain 
 ( ' painful aching in the mouth ' ( ohip 3 ) and ' uncomfortable to eat any foods because 
 of problems with teeth , mouth or dentures ' ( ohip 4 ) ) .
c = psychological discomfort 
 ( ' have been self - conscious because of teeth , mouth or dentures ' ( ohip 5 ) and ' have 
 felt tense because of problems with teeth , mouth or dentures ' ( ohip 6 ) ) .
d = physical 
 disability ( ' diet has been unsatisfactory because of problems with teeth , mouth 
 or dentures ' ( ohip 7 ) and ' have had to interrupt meals because of problems with 
 teeth , mouth or dentures ' ( ohip 8) ) .
e = psychological disability ( ' difficult to 
 relax because of problems with teeth , mouth or dentures ' ( ohip 9 ) and ' have been 
 a bit embarrassed because of problems with teeth , mouth or dentures ' ( ohip 10 ) ) .
f = social disability ( ' have been a bit irritable with other people because of problems 
 with teeth , mouth or dentures ' ( ohip 11 ) and ' have had difficulty doing usual jobs 
 because of problems with teeth , mouth or dentures ' ( ohip 12 ) ) .
g = handicap ( ' have 
 felt that life in general is less satisfying because of problems with teeth , mouth 
 or dentures ' ( ohip 13 ) and ' have been totally unable to function because of problems 
 with teeth , mouth or dentures ' ( ohip 14 ) ) .
the youngest age group ( patients under 65 years of age ) seemed to differ 
 from the older ones , who usually had fewer complaints in the dimensions of the 
 ohip-14 ( figure 2 ) .
the older patients 
 reported ' never ' answers more often than the patients under 65 years of age , 
 whereas the patients under 65 years of age more often reported ' very often ' 
 or ' fairly often ' answers in the ohip-14 questionnaire .
the subjects under 65 
 years of age seemed to be more dissatisfied with their quality of life , especially 
 in terms of psychological discomfort and disability .
they had been self - conscious 
 and had felt tense because of their dentures and more often had had difficulty 
 relaxing and more often had been embarrassed because of problems with their 
 teeth , mouth or dentures .
for example , 87% of the subjects in the older age 
 groups , reported never having difficulty relaxing .
the number of implants supporting the overdenture as well as the connection 
 type ( bar or ball connection ) did not have a statistically significant influence 
 on the ohip-14 values ( p > 0.05 ) ( figure 3 ) . 

it can be seen , however , that patients with two implants and an overdenture 
 reported higher ohip-14 values , but not significantly , which means more dissatisfaction 
 with ohrqol compared with patients with four implants and an overdenture .
slightly 
 higher ohip-14 values , but not significantly , i.e. more dissatisfaction , were 
 also noted with a ball connection than with bars ( figure 
 4 ) .
when comparing the patient groups according to the time elapsed since 
 completion of the prosthetic treatment ( follow - up time 3 to 12 years and 13 
 to 22 years ) , no statistical differences were found in the ohip-14 values .
no statistically 
 significant difference was found between the groups ( p > 0.05 ) .
no statistically significant 
 difference was found between the groups ( p > 0.05 ) .
according to the results of the present study , it can be seen that patients treated 
 with implant - supported mandibular overdentures were satisfied with the outcome of 
 the treatment when evaluated using the ohip-14 questionnaire .
the clinical situation 
 recorded to be good , the prostheses functioned well and only few breakages were 
 recorded in the prosthetic constructions as reported earlier . 

it must be noted that in some cases the follow - up time was over 20 years , and 67% 
 of the patients examined still had their original overdenture in use . 
 in five cases
long implants had been used in mandible , one patient having even 21 
 mm long implants , which was common in the 80 ' to achieve bicortical anchorage to 
 implants .
no statistically significant difference was foundbetween the number of implants 
 supporting an overdenture or the attachment system used when evaluated with the 
 ohip-14 .
older patients were even more satisfied in the aspects of psychological discomfort 
 and disability when compared with patients under 65 years of age .
the people in 
 the youngest age group were usually still involved in working life and had to cope 
 with different social situations , and the demands of oral status might have been 
 higher than in the older age groups .
it has been confirmed that older people often 
 lack the facility to adapt to changes in edentulousness .
the degree of adaptive capacity can be expected to influence the quality of life 
 . on the other hand
, it has 
 been noted that older people are even satisfied with less than ideal oral health 
 and they have less unrealistic expectations of the treatment than younger patients . 

less complaints about oral conditions among the elderly have been noted in several 
 studies , for instance in the uk and the usa , with lower impact rankings in qol reports , 
 that is to say the impact of oral health problems on the quality of life decreases 
 with increasing age .
this study was retrospective and information given by the patients concerning 
 their oral health - related quality of life with the aid of ohip-14 questionnaire 
 was not available before implant treatment .
every patient , however , had a history 
 of severe problems related to use of conventional mandibular dentures . according 
 to the present study , treatment outcome with implant - supported mandibular overdentures 

was found to be good and successful when evaluated with the oral health impact profile 
 ( ohip-14 ) .
the results of this retrospective study show that patients treated with implant - supported 
 mandibular overdentures were satisfied with their oral health - related quality of 
 life .
differences in age groups show that older patients were even more satisfied 
 than younger ones .
gender as well as attachment type or the amount of connecting 
 implants did not seem to be especially significant in this study .
abstractobjectivesthe purpose of this study was to evaluate the oral health - related quality of 
 life of patients treated with implant - supported mandibular overdentures and to compare 
 the attachment systems used.material and methodsaltogether 112 patients treated with implant - supported mandibular overdentures 
 in 1985 - 2004 were invited to the follow - up ; 58 of them attended and replied to 
 the oral health impact profile ( ohip-14 ) -questionnaire . 
 there were 48 overdentures 
 with a bar connection and 10 with a ball connection , the total number of implants 
 installed and still in use was 197 . 
 the mean follow - up time was 13.7 years . 
 the 
 associations between the ohip-14 variables and the patient 's age , gender as well 
 as the number of implants supporting the overdenture and the type of attachment 
 used were assessed.resultsthe results showed that patients with implant - supported mandibular overdentures 
 were satisfied with their oral health - related quality of life ( ohrqol ) . 
 older patients 
 were more satisfied than younger ones in both genders . 
 neither the implant connection 
 type nor the number of supporting implants seemed to have a significant influence 
 on the ohrqol.conclusionsespecially older patients with mandibular implant - supported overdentures were 
 satisfied with their oral health - related quality of life . 
 attachment type or the 
 number of supporting implants did not have a significant influence on the oral health - related 
 quality of life .