Abstract
Aims and objectives: To investigate the pattern and causes of tooth loss in patients among eastern part of Libya. Materials and methods: This study carried out at Faculty of Dentistry, Garyounis University, Benghazi, Libya. The out patients undergoing extractions at the Oral Surgery Department were randomly selected for this study between Jan 2007 and March 2008 where a total of 9,570 extractions were performed on 8,514 patients. The incidence and reasons for tooth extraction, their distribution according to age and sex were studied. Results: Males had more teeth extracted than females. Forty patients had one or more systemic illnesses, 34 were on regular medication. The study revealed two major causes of tooth loss: dental caries (55.90%) and periodontal diseases (34.42%). Other important causes were trauma (3.76%), impaction (1.83%), prosthodontic reasons (2.19%), and orthodontic reasons (1.30%) and others which included extraction where the tooth was associated with a tumour, cyst or supernumerary tooth (1.61%). Dental caries was the main causes of tooth loss during the 2nd, 3rd and 4th decades. While periodontal diseases were the prevalent aetiological factor during the 4th, 5th, 6th and 7th decades of life. The posterior teeth most frequently extracted due to dental caries were lower first molars (43.92%). Whereas anterior teeth were more frequently extracted due to periodontal diseases (28%) with the remaining posterior teeth also being extracted (7%).
Key words: Dental caries, periodontal disease, tooth extraction
INTRODUCTION
Loss of permanent teeth can result from various events, either teeth are extracted by oral care providers or they are lost spontaneously due to progression of periodontal diseases or other events such as dental trauma1. Dental caries and periodontal diseases are the main reasons for tooth extractions, socio-economic-, behavioural- and attitudinal characteristics tend to influence the tooth retention profile of populations2., 3., 4., 5., 6., 7..
The causes of tooth loss have been studied in various countries, including the USA8, Canada9, East Germany, Australia10 and others11., 12.. WHO set oral health goals, objectives and targets in Global Goals for Oral health 202013, one of which regarding tooth loss is to increase the number of individuals with functional dentitions.
Information on the patterns of tooth loss in a population is important for the planning of dental health services, since mortality of the dentition is not only a gauge of the success of curative measures, but also an important indicator of the type and extent of interventions that may be required in a given population. In order for a rational basis for such interventions to be developed, it is important that the reasons for the loss of teeth be identified. Current concepts about the pattern of dental diseases in developing countries are that periodontal diseases are generally severe and widespread, and that the prevalence of dental caries, although until recently low, has been on the increase13. Recent information about dental caries in East Africa indicates that the level of caries tends to be relatively low by international standards14., 15., and there appears to be little evidence of any increase during the last decade16. Depending on how periodontal diseases are defined in epidemiological studies, the reports on the prevalence and severity of these diseases tend to vary considerably among populations17.
The pattern of periodontal breakdown appears to be such that periodontal diseases may not be the major cause of tooth loss in Africans17., 18., 19. and in inhabitants of other developing countries16. In order to obtain convincing data on the relative role of dental diseases in causing mortality of the dentition, one must be able to identify a population which has minimal interference from formal dental services and is representative of the general life-styles and socioeconomic conditions prevailing in the country. In Libya no such studies have been undertaken so far to our knowledge.
Therefore, the aim of this paper is to report on the pattern and reasons for tooth loss and their distribution according to age and sex of the patient in a random sample.
MATERIAL AND METHODS
This study took place at the Faculty of Dentistry, Garyounis University, Benghazi, Libya. The Faculty is the only single institute for the people living in the eastern part of Libya. Out-patients undergoing extractions at the Oral Surgery Department were randomly selected for this study between Jan 2007 and March 2008 where a total of 9,570 extractions were performed on 8,514 patients. The age of the patients ranged from 10 to 80 years. Diagnostic procedures were carried out, and indications for dental extractions noted for each case. Other information such as age, sex, past and current medical history were noted.
Inclusion of all those cases with the age ranging between 10 and 80 years was selected. Cases not requiring an extraction or who refused treatment were excluded. Ethical approval was given by the ethical committee, Information and Review Board and informed consent was sought from each patient who underwent extraction.
RESULTS
A total of 9,570 dental extractions were carried out on 8,514 patients, an average of 1.12 teeth lost per patient. The major causes of tooth loss fall into seven categories (Table 1). Dental caries and periodontal diseases accounted for more than 89% of all teeth lost. Loss due to dental caries was highest in the first three decades of life; however this percentage tapered off in subsequent decades (Table 2). Loss due to periodontal disease was seen at an age as early as 20 years old and rapidly increased with age. However there was no loss due to periodontal disease in the first 10 years of life.
Table 1.
Major causes of tooth loss
| Major causes | Number of teeth lost (%) |
|---|---|
| Dental caries | 5350 (55.90) |
| Periodontal diseases | 3294 (34.42) |
| Trauma | 260 (3.76) |
| Impacted teeth | 176 (1.83) |
| Prosthodontic problems | 210 (2.19) |
| Orthodontic problems | 125 (1.30) |
| Other causes | 155 (1.61) |
| Total | 9570 |
Table 2.
Teeth most frequently extracted due to Dental caries (n = 5350)
| Teeth | Number (n = 5350) (%) |
|---|---|
| 1st Molar upper | 2350 (43.92) |
| 1st Molar lower | 1750 (32.71) |
| 2nd Molar upper | 550 (10.28) |
| 2nd Molar lower | 375 (7) |
| 3rd Molar upper | 125 (2.33) |
| 3rd Molar lower | 5 (0.093) |
| Premolar Upper | 55 (1.02) |
| Premolar Lower | 65 (1.21) |
| Anterior teeth Upper (Central, Lateral and Canine) | 45 (0.84) |
| Anterior teeth Lower (Central, Lateral and Canine) | 30 (0.56) |
Age and sex distribution
Tooth mortality was highest in the 2nd, 3rd, 4th and 5th decades of life (Table 2); 68% of total tooth loss occurred during these four decades of life. Males outnumbered females in the average tooth loss per patient; accounting for 64.69% extractions compared with females patients at 35.41%.
Dental caries
Tooth loss due to dental caries constituted 56% of the total loss seen in this study. The teeth most frequently affected were the molars, whose loss accounted for 53.86% of all extractions due to dental caries (first molars 76% second molars 18% and third molars 4%). Anterior tooth loss due to dental caries amounted to only 2%, while the corresponding premolar loss was 2.23% (Table 3). Teeth lost due to extensive gross caries accounted for 58.99%, proximal caries 20.89%, occlusal caries 13% and cervical and root caries 7.12% from all carious teeth lost.
Table 3.
Causes of tooth loss in relation to age group and Sex of the patient
| Dental caries (%) | Periodontal diseases (%) | Trauma (%) | Impacted teeth (%) | Prosthodontic problems (%) | Orthodontic problems (%) | Other causes (%) | Total | |
|---|---|---|---|---|---|---|---|---|
| Sex | ||||||||
| Male | 3785 (61.13) | 1795 (28.99) | 175 (2.82) | 126 (2.03) | 184 (2.97) | 51 (0.82) | 75 (1.21) | 6191 |
| Female | 1565 (46.17) | 1499 (44.23) | 85 (2.5) | 50 (1.47) | 36 (0.1) | 74 (2.18) | 80 (2.36) | 3389 |
| Age in years | ||||||||
| 10–20 | 1695 (31.68) | 0 | 157 (60.38) | 25 (14.20) | 0 | 30 (24) | 16 (10.32) | 1923 (20.09%) |
| 21–30 | 1760 (32.89) | 80 (2.39) | 65 (25) | 76 (43.1) | 16 (7.61) | 95 (76) | 34 (21.93) | 2126 (22.21%) |
| 31–40 | 580 (10.84) | 95 (2.84) | 28 (10.76) | 30 (17.04) | 34 (16.19) | 30 (919.35) | 797 (8.32%) | |
| 41–50 | 564 (10.54) | 1185 (35.5) | 10 (3.84) | 25 (14.2) | 75 (35.71) | 25 (16.12) | 1884 (19.68%) | |
| 51–60 | 395 (7.38) | 1224 (37.15) | 20(911.36) | 45 (21.42) | 15 (9.67) | 1699 (17.75%) | ||
| 61–70 | 339 (6.33) | 450 (13.49) | 34 (16.19) | 20 (12.90) | 843 (8.80%) | |||
| 71–80 | 17 (0.31) | 260 (7.79) | 6 (2.85) | 15 (9.67) | 298 (3.11%) | |||
| Total | 5350 (55.90) | 3294 (34.42) | 260 (3.76) | 176 (1.83) | 210 (2.19) | 125 (1.30) | 155 (1.61) | 9570 |
Periodontal diseases
Periodontal disease was responsible for the loss of 34.42% of all teeth in this study. Here again the molars were the most affected; 52.33% (20.31% first, 18.70% second and 34.65% third molars). Anterior tooth loss amounted to 34.65% with central incisors more frequently lost than other anterior teeth. Premolar losses were 13.02%, while dental caries was the most prevalent aetiological factor for tooth loss during the first four decades of life among Libyans; periodontal disease was found to be the primary factor for tooth loss after the fourth decade of life.
Trauma
Tooth loss due to trauma constituted 3.76% of the total, with the vast majority of teeth lost during the first 10 years. Anterior teeth were the commonest teeth extracted due to trauma.
Loss of teeth due to impaction, prosthodontic and orthodontic problems
These three aetiological factors were responsible for only 5.32% of tooth loss. Tooth impaction involved largely the lower 3rd molar (63.60%) followed by upper 3rd molars (22.96%) and then upper cuspids (8.83%), prosthodontic-related extractions occurred mostly during 3rd, 4th, 5th and 6th decades and molars were the most affected teeth (89.51%). Extractions carried out for orthodontic purposes affected mostly premolars (76%), and usually during the 2nd decades of life.
Other causes of tooth loss
All other causes of tooth loss included hypoplasia, supernumerary teeth, cysts and attrition accounted for 1.61%.
DISCUSSION
The present study indicated that causes of tooth loss among Eastern Libyans can be divided into major and minor causes. Dental caries and periodontal diseases constitute the major causes, while trauma, impaction, prosthodontic, orthodontic and other reasons (hypoplasia, supernumerary teeth, attrition and cystic lesions) constitute minor causes. The majority of the impacted teeth were third molars.
The present study clearly demonstrates that dental caries is the principal cause of tooth loss in all ages up to 65 years in a population in which there is minimal access to formal dental care. Though this finding is in conflict with the traditional view that periodontal diseases are the major cause of tooth loss beyond the age of 40 years20, it is in accordance with more recent findings in Tanzania19., 21., Finland22, the Netherlands23., 24. and Sri Lanka25.
Our data suggest, moreover, that over the age of 30 years periodontal diseases are a significant cause of tooth loss. Moreover, the finding that the number of teeth indicated for extraction for caries (55.90%) far exceeded those indicated for extraction for periodontal diseases (34.42%).
Not surprisingly, molars accounted for the majority of teeth that had been extracted or were indicated for extraction in all age groups. The principal cause of the loss of these teeth was caries. Periodontal diseases were the principal cause of loss of incisors in the older age groups, and this pattern was broadly similar to that reported for Tanzanian populations21. However, a greater proportion of maxillary incisors had been extracted for periodontal diseases. More than one-third of the teeth were extracted for dental caries (34.4%) and the reading was less compared to the present study although teeth extracted due to periodontal disease26 were (33.1%) which is similar to our study. Caries and its sequelae (63.2%) was the major reason for extractions followed by recurrent pericoronitis (26.3%) and periodontitis (9.2%)27.
Caries was the main reason for extraction in patients under 50 years, whereas periodontal disease was the most common reason in the over-50 age group28. The results obtained similar to our study. The first and second molars and the premolars were extracted most often because of caries; more than half of the incisors and the canines were extracted for periodontal reasons. Patients who had their teeth removed for caries were significantly younger than those who had them extracted for periodontitis (P = 0.000). The third molar was the most frequently extracted tooth and 41.3% were removed due to reasons of impaction, in particular from the mandible, which was a higher reading compared to our study28.
The majority of the teeth removed for prosthetic reasons, 57.1%, were incisors and canines, especially in the mandible; whereas in our study the teeth extracted for the above mentioned reason was around 2.19%. Of the teeth extracted for orthodontic reasons, 47.4% were first and second premolars, whereas in our study the teeth extracted represented 1.30%. The prevalence of subjects with at least one tooth extracted for dental caries and for periodontal disease were respectively significantly higher than other reasons28.
Ong et al.29 showed that caries and periodontal disease were of equal importance but the majority of their sample was aged <40 years. In 1999, caries with its sequelae was the most important reason for extraction and accounted for 54.7% of all extractions, reflecting its very high prevalence in Scotland. Only in Finland22 in 1984 has a higher figure been recorded. With caries such a dominant risk factor for tooth loss, extractions caused by periodontal disease were much less frequent.
Many teeth could be lost to caries in young adults before they could be threatened by periodontal disease. Many of those teeth remaining would be so severely compromised by caries and restorations that they would be at great risk of extraction caused by later endodontic or other restorative problems. There were proportionately more extractions for caries in males than in females. This could mean that males have more caries, are less likely to maintain restorations or are more likely to opt for extraction than restoration.
Caries (and its sequelae) was the major reason for extraction in all age groups over 20 years. Extractions for periodontal disease peaked in the 41–50 year age group but were still less than for caries. It may be that extractions caused by caries are happening later in the disease process, perhaps following initial attempts to treat the tooth. In other words if more teeth are restored rather than extracted then extractions will be deferred to an older age group. Thus the continuing high frequency of extractions for caries may reflect an increase in restoration prior to extraction rather than a high incidence of caries in older people. The subjects investigated in this study experienced tooth loss similar to that observed decades ago in Tanzania and Kenya16., 21.. It contrasts markedly with findings of much more extensive tooth loss in Sri Lanka, USA and Brazil25., 30., 31..
The mean tooth loss of 0.35 teeth estimated in our study compares with 5.9 teeth for Tanzanians (61–69 year olds); recent surveys of the USA and Brazilian populations have reported means of 13.2 and 18.1 teeth lost in comparable age groups30., 31.. A previous survey of the Tanzanian population revealed a figure for tooth loss due to caries was higher (83%) than the present study (56%) 21. Sarita et al.32 reported a higher frequency of tooth loss among Tanzanian adults than what was obtained in this study.
The presence of a positive relationship between age and tooth loss is in agreement with some investigations, but at variance with others6. Consistent with results from previous studies, the present one revealed that caries was the major cause of tooth loss across the age groups investigated16., 21., 30.. Greater tooth loss in women than in men has been reported in many countries, although the reason for this gradient is still unclear2., 31. which was in contrast to our studies. Thus, the greater number of teeth lost due to caries in men appears to be related to dental caries experience and use of dental care services. Other studies have implicated periodontal disease as the leading cause of tooth loss as well as a higher prevalence of edentulous subjects in males compared to females5.
Findings from previous studies suggest that subjects of higher education and greater economic status tend to have the lowest risk for tooth mortality1., 33., 34., 35.. It is probable that wealthy people afford preventive dental check-ups and conservative treatment that contribute to the retention of their teeth. In the present study, subjects who confirmed dental attendance frequently and when having problems had a higher frequency of tooth loss due to dental caries. For emergency oral health care, extraction of teeth was the treatment offered for dental caries almost on a routine basis36. Studies in Tanzania have reported on few teeth with increased mobility even in individuals with extensive loss of supporting bone and on a relatively low frequency of teeth lost due to periodontal breakdown37.
Examining the distribution of dental caries within the dentition revealed however, a closer resemblance with the distribution of tooth loss due to caries than with the distribution of tooth loss due to other reasons across all age groups investigated21.
Baelum reported mandibular incisors to be among the teeth most affected with loss of attachment. As shown previously in Tanzania and elsewhere, anterior teeth predominated among teeth lost due to other reasons, whereas posterior teeth predominated as teeth lost due to caries16., 21., 31..
CONCLUSION
Benghazi, the second city in Socialists Public Libyan Arab Jamahariya has made free dental treatment available to everyone and the people are encouraged to take advantage of this. This study can help in designing and implementing dental public health programmes which can be aimed at reducing the impact of oro-dental diseases on society’s well being. Information on the reasons for extraction of permanent teeth and characteristics of patients can help the dental fraternity to provide appropriate public health strategies for prevention and treatment of oral disease.
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