GAP Australasian-Dentist-May June 2019

Category 68 AustrAlAsiAn Dentist serum level of vitamin D was 25.5 (±13.2; median 24; range 8–55; and 95% Ci, 20.6– 30.4). statistical analysis reported a rather low incidence of early failures (2.2%) in patients with blood vitamin D levels >30 ng/ml. the incidence of early failure was almost double in patients with insufficient serum levels of vitamin D (10–30 ng/ml) and became even higher (9.0%) in patients with serious vitamin D deficiency. Although the statistical analysis revealed a trend toward an increased incidence of failure in patients with severe vitamin D deficiency, the analysis did not reveal a statistically significant difference ( P = 0.15) in the incidence of early implant failure in these three groups of patients. similar results ( P = 0.14) were obtained comparing the incidence of failures in the group of severely deficient patients (2/22: 9.0%) with the incidence of failures in all other patients (25/800: 3.1%). Finally, the statistical analysis did not reveal a significant difference ( P = 0.13) when comparing the incidence of failures in the group of patients with serum vitamin D levels >30 ng/ml (9/394: 2.2%) with the incidence of failures in all other patients (18/428: 4.2%). the details of early failure were reported in table 2. 4. Discussion A relatively small number of experimental studies has attempted to investigate the effects of vitaminDon the osseointegration of dental implants [24–32].the majority of these studies would appear to indicate a positive effect of vitamin D on 3. Results Of the 915 patients originally evaluated for enrolment in this study, 93 presented with conditions corresponding to the exclusion criteria and were therefore excluded from the assessment. By contrast, 822 patients (mean age 57.3 ± 14.2 years; median age 58; range 18–90; and 95% Ci, 56.3–58.2), receiving 1625 implants, did not have any of the conditions contained in the exclusion criteria and were therefore enrolled into this retrospective study. the distribution of patients by groups, with relative incidence of failures, was reported in table 1. in total, 27 early failures were recorded (19 due to failure of osseointegration and 8 due to periimplant tissue infection), with an overall incidence of 3.2%. no differences were observed in the incidence of early failures between males and females ( P = 0.97) nor according to age at time of surgery ( P = 0.98). Although the percentage of early failures in smokers was slightly higher than that detected in nonsmokers, there was no statistically significant difference ( P = 0.56) between these two groups of patients. the same was true for patients with a history of periodontal disease; they displayed a slightly higher incidence of early failures than patients who had not been affected by periodontitis, but this difference was not significant ( P = 0.73). the average serum level of vitamin D in the general population was 29.9 ng/ml (±12.1; median 29; range 5–73; and 95% Ci, 29.1–30.7). in patients in whom early implant failure occurred, the average spreadsheet (excel, Microsoft Office, redmond,MA,usA)whichwasusedforthe descriptive, qualitative, and quantitative analyses. the mean, standard deviation, median, and confidence intervals were calculated for the quantitative variables (e.g., patients’ age and vitamin D levels in serum). A patient-based technique was used to calculate implant survival. in this analysis, the “event” was implant failure: thus in patients receiving more than one implant, the occurrence of even a single implant failure led to the patient being classified as a “failure.” the influence of different variables on implant survival was taken into consideration: gender (male or female), age at time of surgery (three age groups were examined: <40, 40–60 years, and >60 years), smoking habits (regardless of the actual number of cigarettes smoked), a history of chronic periodontitis [36], and serum levels of vitamin D. in the analysis of serum levels of vitamin D, three classes of patients were considered: severely deficient patients (serum vitamin D <10 ng/ml), patients with low levels (serum vitamin D between 10 and 30 ng/ml), and patients with adequate levels (serum vitamin D >30 ng/ml). the influence of each of these variables on implant survival was calculated using the Chi square test. the significance level was set at 0.05. the overall implant survival, the survival within the different groups, and the analysis of the influence of the different variables on survival were all made using dedicated statistical analysis software (sPss 17.0, sPss inc., Chicago, il, usA). lInICal Table 1: Distribution of patients (by gender, age at surgery, smoking habit, history of periodontal disease, and vitamin D levels in serum), related failures, survival rate within groups, and differences between groups (Chi square test).