Periodontal health in children with diabetes mellitus type 1 in Montenegro

Summary Introduction Separation of instruments in the root canal is one of the challenges in endodontic treatment. More specifically, nickel-titanium (NiTi) rotary instruments usually separate without previous deformation. The aim of this pilot study was to assess the effect of torsional stress on endodontic NiTi rotary instruments separation in simulated clinical conditions. Materials and methods Research was conducted on a sample of 20 human teeth in laboratory conditions. Experimental procedure consisted of determining canal curvatures for each root on digital radiographs and root canal treatment using endodontic NiTi rotary instruments. Out of 20 teeth (60 canals), two groups were formed with similar root canal curvatures (10 pairs of teeth) and instrumented using NiTi rotary instrument with or without torque control. Results Wilcoxon matched pair test showed no statistically significant difference in average number of instruments use with or without torque control (p>0.05). Conclusion Even though there is no statistical significance in instrument separation when instruments were used with or without torque, there is tendency to experience sudden fracture of instruments after work without torsional control even after only few uses in clinical work.


INTRODUCTION
Diabetes mellitus (DM) is systemic metabolic disorder characterized by hyperglycemia (a persistent increase in blood glucose level) resulting from insulin secretion disorder, disturbance of its function or both [1,2]. It is one of the most common endocrine disorders, with prevalence in the constant rise especially in developed countries. This is due to the modern lifestyle and increase in the number of external etiological factors, among which obesity is particularly noticeable. DM is most common in older age as a result of general degenerative and sclerotic changes in the body (which also involve pancreas) while in children it may be due to genetic disorders or pancreas damage in certain infectious diseases [1,2].
The incidence of DM in childhood is constantly increasing. The number of children with DM doubles every other decade. Every ten seconds in the world one person dies of diabetes, and two new ones get sick. Children in 98% of cases experience unstable, ketosis-related, insulin-dependent diabetes mellitus (type 1), which is most commonly diagnosed in puberty [2,3]. Like all systemic diseases, DM gives many complications. The significant impact of this disease is on oral health.
Large number of studies has shown that prevalence, progression and severity of periodontal diseases have been significantly increased in patients with DM. The on-set and progression of periodontitis in patients with DM is probably caused by diabetic microangiopathy, impaired immune response and reduced resistance to infection. In patients with DM, periodontal disease occurs at younger age compared to healthy population. In children with DM, periodontal damage is usually manifested in adolescence, and very often earlier [4,5].
The aim of this study was to determine whether periodontal health of children with type 1 diabetes mellitus was different from healthy children.

METHODS
Ethical Committee of the Clinical Center in Podgorica, Montenegro approved this research. One dentist performed all examinations. Kappa values evaluated after the study for inter-rater agreement amounted to 0.94.
The study included 87 children of both genders, aged 10-15 years, suffering from Type 1 diabetes mellitus (DMT1) from all over Montenegro. These children were treated at the Institute of Child Diseases in the Clinical Center of Montenegro. Only those children whose parents had given their consent were included in the examinations. Data about history of disease, including the type of DM and values of glycosylated hemoglobin (HbA1c) not older than six months, were obtained from the medical records of patients. These children were included in one group (DMT1).
The control group included 90 healthy children of both genders; age 10-15 years, selected by random sampling method, and attending elementary school in the area of Podgorica municipality. Their parents also signed informed consent. All children who participated in the study were examined with standard dental diagnostic tools on dry teeth, with artificial lighting in dental chair.
The condition of oral hygiene was determined by Green-Vermilion plaque index, which determines the absence or the presence, quantity and distribution of dental plaque and other soft deposits on representative permanent teeth [6]. Loe-Silness gingival index was used for the clinical assessment of gingival tissue health on vestibular, oral, mesial and distal surfaces of each tooth [7]. Community Periodontal Index [8] was used to assess the condition of periodontal tissue according to the recommendations of the British Association for Periodontology and the British Association for Pediatric Dentistry (Guidelines for Periodontal Screening and Management of Children and Adolescents Under 18 Years of Age) [9]. For this purpose, special periodontal probe marked at 1, 2, 3, 5, 7, 9 and 10 mm, with 0.5 mm diameter ball at the end was used. This graduated probe was adapted for precise measurement of the clinical attachment level or periodontal pockets.
During examination, with slight pressure, the probe was introduced into the space between the teeth and gingiva, with the anatomical configuration of the teeth being monitored. The pressure at this measurement was 15-20 g and much lighter than the pressure used in usual probing of periodontal pockets [8]. For this purpose, the following representative teeth were examined: upper and lower first permanent molars, upper right first permanent incisor and lower left first incisor. For each tooth the following four measurements were conducted: mesiobucal, bucal, distal and oral. Depending on the clinical finding, each quadrant received appropriate score. The scoring was done as follows: Score 0 -healthy periodontal tissue; Score 1 -gingival bleeding after probing; Score 2 -the presence of solid deposits on teeth (supra and subgingival calculus) or the existence of prominent edges of the fillings; Score 3 -shallow periodontal pockets 4 -5 mm; Score 4 -deep periodontal pockets (6 mm or more). Out of these four, the finding indicating the worst condition of periodontal tissue was recorded. For each quadrant, only one digit 0 -4 was determined, which represented the worst condition in that quadrant. If some of the representative teeth were missing, that quadrant was not taken into account. Thus, for each respondent, the individual maximum value of this index was determined and it indicated the need for and type of necessary treatment.
It should be emphasized that it is not recommended to measure the pockets depth in children 7 to 11 years old. In children under 12 years of age, periodontal health was determined based on the clinical state of gingiva and presence of solid deposits [9].
In our study, children under the age of 12 also did not have CAL measured, while for children older than 11 years the same teeth were used as for CPI index [9]. The measurement was performed by graduated dental probe with a ball on the top, in the middle of the vestibular surface and at the connection of mesial and vestibular surface. The probe was placed in the sulcus parallel to the longitudinal tooth axis [9]. The measurement results were given for each representative tooth.
For descriptions of parameters and depending on their nature, the descriptive statistics were used: mean value, standard deviation (SD) and percentage. To test statistical significance of average values between two independent samples, Student's t-test and Mann-Whitney test were used. P values of less than 0.05 were considered statistically significant. Statistical data processing was done in SPSS v.11.5 for Windows.

RESULTS
A total of 177 children aged 10-15 years participated in the study. The average age of children suffering from DMT1 was 12.7 ± 1.6, while the average age of children from the control group was 12.8 ± 1.6.
In the sample of children with DM, the mean PI was 1.31 ± 0.55, while the average value of this indicator in the control group of children was 1.03 ± 0.51. Children with diabetes had significantly higher average plaque index values compared to healthy children (Table 1). Of the total number of children in the group DMT1, healthy gingiva was found in 6.8%, mild inflammation in 17.2%, moderate inflammation in 58.6%, and severe inflammation in 17.2% of children. In the control group, healthy gingiva had 26.7% of children, mild inflammation 43.3%, moderate inflammation 22.2% and severe 7.8%. Respondents from the DMT1 group had the highest percentage of moderate and severe gingival inflammation while subjects in the control group had more healthy gingiva and mild inflammation ( Table 2). There was significant difference in gingival health between control and DMT1 group (p < 0.05; Mann-Whitney test).
Significantly higher percentage of children with healthy periodontal tissue was registered in the control group 55.6% (p <0.05; Mann-Whitney test). On the other hand, in children with DM, the highest percentage of children had gingival bleeding (36.7%) which was statistically significant (p <0.05; Mann-Whitney test). Healthy periodontal tissue in DMT1 group was recorded in 24.1% of children, while the presence of solid deposits was registered in 17.2%. The presence of periodontal pockets of 4-5mm was found in 21.8%. Respondents from the control group had bleeding after probing in 31.1%, solid deposits in 7.8%, and 4-5 mm pockets in 5.6% of examined children (Table 3). Children with DM compared to children in the control group had significantly worse periodontal disease (p <0.05; Mann-Whitney test). The score 4 for CPI index value was not registered in any group.
The average value of CPI index in the DMT1 group was 1.36 ± 1.12 and it was significantly higher (t = 5.58; p = 0.000) compared to members of the healthy group (0.59 ± 0.84) ( Table 1).
The mean value of CAL in children with DMT1 was 1.33 ± 0.60 while in healthy children it was 0.66 ± 0.53 (Table 1). Healthy children had significantly lower clinical attachment level than children with DM (t = 5.58; p = 0.000).

DISCUSSION
The results of studies found in literature indicated that children with DMT1 had poorer oral hygiene, higher incidence and severity of gingivitis compared to healthy children. Likewise, we found that healthy children had more often healthy periodontal tissues. Gingival bleeding after probing was more common in the group of DMT1. Most studies concluded that the incidence of gingivitis in patients with DMT1 was significantly higher than in healthy population and increased with age [10]. In her research, Dakovic found that children with DMT1 in Serbia had more dental plaque, gingivitis and periodontal destruction, which is in agreement with the results of our study [11]. In large Brazilian study, it was found that children with DM had higher percentage of gingivitis and periodontitis compared to healthy children [12]. Children with DMT1 in Lithuania and Turkey had more dental plaque and worse gingival health than healthy children, which is in correlation with the results of our study [13,14]. Increased glucose levels in gingival fluid and blood and decreased salivary secretion in patients with DM changes micro flora causing qualitative changes in bacteria that are responsible for the occurrence of periodontal problems [13,15]. Karjalainen et al. noted that unbalanced glucose metabolism in diabetic patients is in direct correlation with the degree of gingival inflammation [16]. The pronounced gingival bleeding due to hyperglycemia can be explained by immunological changes occurring due to reduced resistance to organic deposits in dental plaque. Periodontal disease is reported as the sixth complication of diabetes mellitus [4]. The prevalence, severity and progression of periodontal disease are higher in these patients compared to healthy subjects [10,[17][18][19][20][21]. Dakovic et al. obtained similar results in children with DMT1 in Serbia [11]. Also, the study of Lalla et al. confirmed higher periodontal destruction in children with DMT1 than in healthy children [17]. Nevertheless, the results of certain studies have not found significant difference in periodontal disease between children with well-controlled DM and healthy children [19,22]. Oral hygiene habits play an important role in preservation and health of periodontal tissues and prevalence of this disease varies depending on the health habits of each person.
Periodontal disorders begin very early in these children, with tendency to deteriorate periodontal tissues in adolescence. DMT1 adolescents develop earlier and advanced inflammatory reaction of gingiva compared to similar bacterial challenge in healthy children. In addition, it has been shown that severe damage of periodontal tissue occurs more frequently in patients with DM who ere poorly metabolically regulated [10,11,17,18,19]. Therefore, programs for prevention of disease and promotion of periodontal health should be available as soon as possible to this population group [10,11,23].
DM is chronic metabolic disease that affects the entire body, as well as oral health. Health habits are very important in the prevention of oral diseases. Dentists should be focused on promoting good health and oral habits, performing periodic dental examinations and ensuring good oral hygiene in this population group. Dentists must minimize the risk factors for the occurrence of periodontal tissue diseases caries and other soft tissue disorders, as well as to carry out continuous health work and motivation of these patients with regards to oral hygiene [13].

CONCLUSION
The results of the current study indicate that children with type 1 diabetes mellitus in Montenegro have more dental plaque, more gingivitis and periodontal disorders than healthy children. It is necessary to propose a plan of preventive activities aimed to educate and implement prophylactic measures related to reduction of dental plaque and dental calculus.