Oral Health Status in Adult Population in Chile ( Decayed , Missing , Filled and Permanent Tooth ) : Clinical Observation at National Level

Objectives: The aim of this study was to establish the differences in the oral health status of adult population between women and men by the clinical status of the permanent first molar. Methods: The data were obtained in a non-random sample of 132,174 patients from a large cohort who were under dental treatment nationwide in Chile during 2011. Results: The results show a greater frequency of “filled and not decayed” (45.6%), “decayed” (18.8%) and followed by “missing by decay” (15.4%). Moreover, an association is established between the “filled and decayed” condition to the female gender and the condition “decayed” and “missing by decay” to the male gender (Significance level α ≤ 0.05). Conclusions: This study concluded that there was a dependent association between gender and the oral health status of permanent first molars in adult patients.


Introduction
The study of damage related to dental caries in adults at a global level is scarce, and in recent years is an epidemiological concern because it drives us to the needs of dental treatment.There are a few studies that account for the oral health status of Chilean adults [1]- [3] and according to the Health Ministry of the Government of Chile, the population older than 20 years old are the most affected in the perception of their quality of life [4].National studies carried out by the Chilean Ministry of Health, and by the National Health Survey in 2003 [5] involved 3308 people over 17 years old, based on the presence of decay teeth, remaining teeth, and dental prosthesis use, this examination was carried out at home by a calibrated nurse.The studies are mainly based on the use of ranges of damage by the index: D:decay, F: filled, M: missing, T: permanent tooth (DFMT), which has been used for 70 years, originally aimed to children, but today efforts involve the older adult population [6].In 2007, a study of 12 years old population, supported it by the government of Chile, showed an increased prevalence of caries-free teeth in men and greater DMFT index on women [3].Recent studies on oral health status in adults made in South Vietnam [7] (n = 2965), Bulgaria [8] (n = 2531), China [9] (n = 1588) and Tanzania [10] (n = 5532), conclude that the molar teeth have an increased risk of carious lesion or being missing than the anterior teeth and premolars, but the association of gender with DFMT index and its components is variable.For studies conducted in South Vietnam [7] and China [9], females had increased risk of caries lesions, greater chance for sealed and lower risk to being missing, in Bulgaria females had greater risk for missing teeth and filled teeth.The study in South Australia [11] (n= 709) found that males had fewer risk for missing teeth, unlike Brazil study [12] (n = 1159) where males had a greater risk for missing teeth and increased risk of carious lesions.The benefits in the oral health are directly reflected in better chewing ability of the adult population when the molars are presented [13].In view of the above, the objective of this study was to establish the association of oral health status by gender in adult patients undergoing dental treatment in Chile through the clinical examination of the permanent first molars.

Material and Method
This study is not experimental, exploratory and transversal [14].It was approved by the Research Ethics Committee of the Universidad Finis Terrae before starting.The encoded data, impossible to identify participants, was obtained from the records contained in electronic medical record and correspond to the total number of cases admitted into private oral health centers from a nationwide network in 2011.The demographic characteristics of the study population have been described in a previous paper [15].The study population was 648, 235 cases, the sample (n = 132, 174) was not randomized.From the observed data of the complete medical records of adults patients, aged 20-64, the conditions of the permanent first molar was studied (3P, 14P, 19P and 30P: according to FDI nomenclature (World Dental Federation), were estimated frequency, and cumulative percentage of each conditions relating to the dental status of the permanent first molars, these being: decay, filled and decay, white spot, sealant and varnish, filled and not decay, crowned, missing by caries, missing by other reason, unerupted and unexamined.Subsequently, there was calculated the association between the condition of each molar with patient gender by χ 2 test (chi square test) in the form of contingency tables.The level of significance in all cases was α ≤ 0.05.
Table 2 shows that from 127, 875 cases, 56.46% are women.The highest frequency of dental conditions of teeth 16 in men and women were "filled and not decay" followed by "missing by caries" and "decay".The χ 2 test was highly significant (p < 0.0001) (Table 2), which means that the condition of the tooth is associated with the patient gender.Specifically, the masculine gender showed the strongest association with the conditions "decay" and "missing by caries" (observed frequencies higher than expected), while women are associated with the conditions "filled and decay" and "crowned" (observed frequencies higher than expected).
Table 3 shows the results of frequencies, percentages and cumulative percentage of dental conditions studied in the teeth 14P (upper left first permanent molars).These indicators behaved in the same way as the teeth 3P.The χ 2 test was highly significant (p < 0.0001) (Table 4), which means that the condition of the tooth is  associated with the gender.Specifically, the male gender showed the strongest association to "decay" and "missing by caries", while the female gender is associated with "filled and decay", "filled and not decay" and "crowned".Table 5 shows the results of frequencies, percentages and cumulative percentage of dental conditions studied in the teeth 19P (lower right first permanent molars).The highest frequency is "filled and not decay" (38, 9%) as the same in teeth 14P, followed by "missing by caries" (20.8%), "decay" (16.3%), "filled and decay" (6.3%), "sealant or varnish" (0.8%) and "white spot" (0.2%).The χ 2 test was highly significant (p < 0.001) (Table 6), which means that the condition of the tooth is associated with the gender.Specifically, the male gender showed the strongest association to "decay" and "white spot", while the female gender is associated with the condition of "filled and decay", "filled and not decay", "crowned", and "missing by caries".
Table 7 shows the results of frequencies, percentages and cumulative percentage of dental conditions studied in the teeth 30P (lower left first permanent molars).These indicators behave in the same way as in the teeth 19P.The χ 2 test was highly significant (p < 0.0001) (Table 8), which means that the condition of the tooth  is associated with gender.Specifically, the male gender showed the strongest association to "decay" and "white spot", while the female is associated with the condition of "filled and decay", "filled and not decay", "crowned", "missing by caries" and "missing by other reason".

Discussion
This national multicenter study represents a diagnostic reality of oral health status, that establish treatment needs for the permanent first molar, in a large sample (n = 132,174) of the adult population who seek dental treatment in Chile.As a limitation, another network of public or private dental services is not considered.The DFMT index has the significance of being the most used index in epidemiological studies, but does not consider other conditions that may be present and should give more detail to the current state and history of tooth caries, such as "filled and decay "missing by caries", and "missing by another reason".The study results reveal a high presence of healthy filled molars (45.6%), molars with carious lesions (18.8%) and molars missing by caries (15.4%).Specifically, this study demonstrates that gender is associated with the condition of the first molars in women differently than men.The finding of an independent association of gender was "healthy filled" condition.The results of this study are consistent with previous national studies, the National Health Interview Survey (NHIS) conducted in 2003 by the Ministry of Health, Government of Chile [5], which significantly demonstrates that men have more caveated caries lesions (decay) than women (n = 3308, mean 2.97 vs 2.08 injuries respectively) and higher caries rate (69.7 vs 63.0), also showed that the age group most affected with caries was between 25 to 44 years old, meanwhile this study showed significant differences between men and woman, where the condition with highest rate in men was "decay", while in women was "filled and decayed", is also consistent the rate of caries lesions found in this study with outcomes of NHIS, represented in "filled and decay" and "decay" both reach 64.4% versus 66.0% respectively.In light of the results obtained and given that the presence of caries lesions have the greatest impact on quality of life related to oral health, according to studies in India [16] (n = 1200), issues that require attention are raised in oral health of adults referred to damage by caries, e.g. the need for preventive measures and minimally invasive dental treatment for primary caries lesions in men and caries lesions to restoration in women, the need for prosthetic replacement of missing teeth both in women and men, and greater emphasis on the need for prevention and support therapy in oral health.

Conclusion
The gender is associated with oral health status in adults (p < 0.05).The conditions of the permanent first molars with higher association in women were "filled and decay" and "missing by caries", in men were "decay" and "missing by caries".Due to the limitations of the present study, new multicenter studies are suggested to cover the whole dentition in adults, both in private and public network, in order to understand the damage in a broad context and estimate the real needs of treatment in adults.

Table 1 .
Results of the estimated frequency, percentage of affected persons and accumulated percentage in the upper right first permanent molar (3P).

Table 2 .
Results of association between dental conditions and gender in the upper right first permanent molar (3P).Note: 93 cases lost by lack of information on the gender of the subject under review.

Table 3 .
Results of the estimated frequency, percentage of affected persons and accumulated percentage in the upper left first permanent molar (14P).

Table 4 .
Results of association between dental conditions and gender in the upper left permanent molar (14P).

Table 5 .
Results of the estimated frequency and percentage of affected persons in the lower right first permanent molar (19P).Results of association between dental conditions and gender in the lower right first permanent molar (19P).

Table 7 .
Results of the estimated frequency and percentage of affected persons in the lower left first permanent molar (30P).

Table 8 .
Results of association between dental conditions and gender in the lower left first permanent molar (30P).