INTRODUCTION

Addressing the health problems of prison inmates is a major challenge for public administrations, which are responsible for ensuring that necessary provisions are made to deal with them.

The prison population presents a set of unique social and medical characteristics that should be taken into account when considering healthcare options:

All these factors may be linked or lead to a deterioration in oral health, which should be treated in the prison setting.

The aim of this study is to describe the chronic pathologies of prison inmates, including their risk factors and epidemiological considerations. We also set out to assess the oral symptoms of these pathologies and the consequences for the oral health of this population. We conclude by considering the possible needs for oral treatment that should be provided for and guaranteed in prisons.

GENERAL PATHOLOGY IN THE PRISON POPULATION

The world's prison population has greatly increased in recent years and there has been a parallel increase in the age of inmates. This latter point is important in clinical terms since there are likely to be a larger number of chronic pathologies.

The four main non-communicable chronic diseased identified by the World Health Organisation (WHO) are cardiovascular diseases, diabetes, cancer and chronic respiratoria pathology¹, which are also related to high mortality levels. Although such diseases affect individuals of all social levels, there is a higher incidence of them in more disadvantaged strata, where many inmates often come from.

A study by Vera Remartínez et al. on a total of 1,077 subjects interviewed in nine Spanish prisons established a prevalence of dyslipidaemia of 34.8%, high blood pressure of 17.8%, diabetes of 5.3%, asthma of 4,6%, COPD of 2.2%, coronary heart disease of 1.8% and cardiovascular diseases of 1.5%. The most notable risk factors included smoking amongst 70.4% of the inmates and cocaine consumption amongst 30.5%; while overweight, obesity and sedentarism was found in 39.6% (12.3% and 38.5% respectively)².

Wright et al. carried out a study in the UK on a total of 199 participants in 2019. The most common diseases were anxiety and depression (34%), followed by respiratory pathology (17%) and high blood pressure (10%); heart disease, stroke, cancer and diabetes presented a similar prevalence, at 2% each. 27% of the subjects had a record of drug abuse and 16% of alcoholism, while 83% of the participants smoked. 19% did no physical exercise during their stay in prison³. A systematic review and meta-analysis by Manna S et al. in India showed that the prevalence of depression amongst inmates stood at 48.78%, making it the most common mental illness in the prison population, which matches the data for prevalence provided by another meta-analysis conducted in Ethiopia, where 44.45% of the population suffered from this disease⁴.

Infectious pathologies are also a major issue in the prison setting. A study carried out in Mexico by Arredondo et al. on the epidemiology of communicable diseases amongst a sample of 17,000 inmates showed the following figures for prevalence: HIV 0.7%; syphilis (Anti-TP+/VDRL+) 2%; Hepatitis B (HBcAc 2.8%, HBsAg 0.15%); Anti-HCV 3.2%⁵.

TBC is often highly prevalent in prisons, especially in developing countries. A meta-analysis by Ferreira on the epidemiology of this infectious disease showed figures for prevalence of active TBC of 3,13% in countries with a low-medium economic level, while this figure dropped to 2.25% in more developed countries⁶.

ORAL SYMPTOMS OF GENERAL PATHOLOGIES

The oral repercussions of these highly prevalent diseases are many and varied; either as a direct result of the disease itself or because of the treatments used. These repercussions are summarised in Table 1.

ORAL DISEASES

As explained above, many of the systemic pathologies described above will have an effect on the pathogenesis of the most prevalent oral diseases: caries and periodontal disease. Table 2 shows the values for the prevalence of caries and the DMFT index recorded in the reviewed publications.

Some studies have highlighted a higher prevalence of both pathologies amongst inmates when compared to the general public. In a study published in 1985, M.A. Cunninghan et al. compared the prevalence of oral disease in a prison population (99 males, from 18-30 years of age) compared to a group of 101 males of the same age group who were not inmates: they found statistically significant differences between both groups in each of the DMFT components (Index of cavities, D-lost due to cavities, M-filled, F), with figures for cavities (3.0) and losses from cavities (1.7) that were much higher in the first group than in the non-inmate sample (0.8 and 0.6 respectively); on the other hand, the figures for filled teeth were much higher in the second group (9.0 compared to 5.6)¹⁰.

M. E Salive et al. carried out a study on prevalence at a prison in the USA in 1989 on a sample of 178 males. They found a mean of the DMFT index of 10.5 in the 18-29 age group, 17.1 in the 30-44 group and 22.4 amongst inmates over 44 years of age. These figures are very high, and are even higher when they are compared to those of the general public, who have fewer teeth lost due to caries and fewer uncovered treatment needs¹¹. Another American study published in 2002 by Heng and Morse showed a DMFT index of 16.8 when analysing a group of 500 female inmates at a prison in Connecticut¹².

Reddy et al. carried out a study that analysed the state of oral health and treatment needs amongst the population of seven prisons in India, in a sample of 800 inmates (722 men and 78 women). The prevalence of caries was 92.5% with a DMFT index of 5.26; deficient oral hygiene was observed in 66.3% of the subjects, 39.3% had a CPI (community periodontal index) of 2 (presence of calculus) and 48.6% had a CPI of 3 or 4 (bags of 4-5 mm. or more)¹³.

Balkrishna et al. published figures about caries after examining a total of 573 inmates (534 men and 39 women). They determined a prevalence of 77%; in this case the DMFT index was similar to the previous one, 5.40 ± 6.49, although they observed a significantly high mean score (p = 0.002) amongst women (5.77 ± 6.188). Furthermore, they found a significant difference when the mean score of this index was compared to the period of imprisonment, where the highest mean score was 6.97 ± 7.69 for 5-10 years¹⁴.

A similar trend was observed by Kumar in a study on a sample of 532 inmates, who were grouped according to the length of stay in prison (less than 3 years, 3 to 6 years, 6-10 years). In this case, the mean DMFT was 7.18 ± 3.93, and this index was seen to increase from a value of 6.34 ± 4.04 in the first group to 8.03 ± 3.78 in the third¹⁵.

On the other hand, Clare observed that there was a major reduction in dental caries (46.3%) amongst individuals who spent more than three years in prison, with a decrease in the component “D: carious” from 6.7 to 3.6. He considered that this was due to filling carious teeth, the extraction of teeth that could not be recovered and availability and access to dental services in prison¹⁶.

Cavalcanti, et al. published a study in Brazil after analysing 127 male prisoners. They recorded a DMFT index of 19.72 ± 6.9, the value of which increased in line with age. The component “D: carious” was the largest one of the index, while component “F: filling” had a mean value of 1.46 ± 2.45, which shows the lack of importance in conservative treatment strategies¹⁷.

Bukhari et al. compared the DMFT index and its components between a group of 82 male inmates at two prisons in Saudi Arabia and a control group made up of 79 individuals of a similar age, gender and educational level. They saw that the percentages of carious teeth (component D) (90.2%) or lost due to caries (component M) (80.5%) were much higher in the study group than in the control subjects (D: 57%, M: 60.8%). On the other hand, the percentage of filled teeth (component F) was considerably lower in the group of inmates (31.7% compared to 50.60%)¹⁸.

Soares et al. carried out a study in Portugal on a sample of 103 male inmates with an average age of 41.58 ± 8.94 years. They found a DMFT index of 17.17 ± 8.23, basically caused by lost teeth, while the average for filled teeth was 1.86 ± 2.48, which likewise highlights the reduced level of treatment received. No significant relationship was found between caries lesions and drug abuse. Of the 96 patients who had teeth, 41.7% suffered from periodontitis, 32.3% from gingivitis, while only 26% were periodontally healthy. In this case there was a statistically significant relationship with tobacco consumption¹⁹.

Akaji and Ashiwaju carried out a study to determine the oral health of 230 inmates (224 men and 6 women) in a prison in Nigeria. One notable finding was that only 5.2% of the participants had a CPI = 0, while 94.8% had some kind of periodontal issue; to a lesser degree amongst those who practiced some form of correct oral hygiene²⁰. Along the same lines, Vainionpää et al. in a study on 100 subjects at a prison in Finland found that 93% had a CPI of 2 or more²¹.

It can be seen then that periodontal disease constitutes a global problem amongst inmates, especially those with a record of drug abuse, who present higher figures for periodontitis²².

As regards diseases of the oral mucosa, Reddy et al. found in their study that 20.5% of inmates presented lesions of the oral mucosa: oral submucosa fibrosis (9.9%), ulcers (9.9%) and leukoplakia (1.1%)¹³. Kondratyev, in a study of 305 inmates (175 men and 130 women) observed a prevalence of bitten mucosa of 53.1%, stomatitis nicotina of the palate (28.8%), leukoplakia (82%), hyperplastic lesions (6.8%), while lingual pathologies and candidiasis were present in 21.9% and 4.9% of the cases respectively. It should also be noted that a sizeable number of these pathologies had smoking as the main aetiological factor²³.

Rawlani et al., carried out a study in India on the prevalence of premalignant lesions of the oral mucosa. They found mean figures of 34.28%, with 25.43% of the inmates diagnosed with oral submucosa fibrosis, and 7.422% with leukoplakia. They felt, as did other authors, that such high levels of oral lesions could be attributed to smoking, although in this case betel nut was also a common factor in this country²⁴.

TREATMENT NEEDS

There are many challenges when providing dental services in the prison setting. These may be due to a number of causes: the negative attitude of many inmates to dental care and health, the lack of available dental care resources in prisons and the difficulties involved in gaining access to external dental services.

The information about risk factors for the most prevalent chronic disease mentioned by Vera Remartínez² and its relationship to different oral diseases, means that it is essential to invest resources: firstly, in health education for prisons; inmates need to know that controlling such risk factors will not only benefit their overall health, but also their oral health. Secondly, it is necessary to implement preventive, corrective and suppressive measures for such factors. These include:

Furthermore, given the awareness of the repercussions of this general pathology on oral health, early diagnosis programmes for these potential consequences should be established (secondary prevention), with regular checkups of the oral cavity and all its structures. Another equally important tool at this stage would be preventive measures (primary prevention) to stop such pathologies from appearing. The following measures are especially important:

As the studies mentioned above indicate, one important factor in treatment needs is that the value of component “F: filled” of the DMFT index is much lower amongst inmates than it is in the general public, which indicates a poor degree of dental care; as is the case with periodontal disease.

Reddy found that 57.1% of inmates had lost one or more teeth due to the lack of dental services. With a prevalence of caries of 92.5% and a DMFT of 5.26, 97.4% of the subjects required correct instructions for oral hygiene, 87.6% needed fillings, 59.2% required pulp treatment, 62.1% needed to have a tooth extracted and 32.2% the repositioning of a tooth lost via a prosthesis¹³.

Korkosz et al. carried out a retrospective study on the needs for dental treatment of a group of 86 inmates compared to a control group made up of 106 men who lived outside prison. They found that the need for endodontic treatment was significantly higher in the study group and that endodontic therapy was significantly less frequent (19 subjects compared to 54) amongst inmates. There were no statistically significant differences between both groups in the quality of treatment, or in the presence of periapical changes or symptoms associated with treatment failure²⁵.

As mentioned above, Vainionpää et al. examined a sample made up of 100 inmates (89 men and 11 women) and determined a CPI of 2 or more in 93% of the individuals, in which 67.7% of those under 30 years of age presented calculus and therefore required scaling, while 29.4% (with a CPI of 3 or 4) required periodontal treatment. In cases over 30 years of age, 49.9% had calculus that needed to be removed with scaling, while 34.4% needed periodontal treatment²¹.

Kumar assessed the need for prosthetic treatment in a sample of 532 inmates. 11.3% required a single crown in the upper or maxillary arch, 6.2% needed several crowns or a fixed prosthesis of several units, 1.3% needed a mixed prosthesis and 0.6% a complete one. In the lower or mandibular arch, 12.2% needed a single crown, 7.5% several crowns or a fixed prosthesis, 2.3% a combined crown and fixed prosthesis and 0.8% a complete lower prosthesis¹⁵.

CONCLUSIONS

The important consequences of chronic disease on oral health and the high prevalence of related oral diseases make it necessary to establish a series of interventions to improve dental care for inmates.