Do traditional techniques produce better conventional complete dentures than simplified techniques? A 10-year follow-up of a randomized clinical trial.

OBJECTIVES: The use of a simplified method (S) of fabricating complete dentures has been shown to be more cost-efficient than the traditional method (T), and there are no negative consequences that detract from the cost savings in the short term. However, it is not clear whether this remains constant over a decade. The objective of this study was to clarify patients' perspectives and determine any differences between the dentures fabricated with these two different techniques after a decade of use. MATERIAL AND METHODS: Edentate individuals participated in a randomized controlled clinical trial and completed a 6-month follow-up from 2001 to 2003 (T group n = 50; S group n = 54). For this 10-year follow-up, they were interviewed by telephone. The assessment included whether the denture was still in use or replaced, the condition of the dentures, patient satisfaction and oral health-related quality of life (OHRQoL). Between and within-group differences and the factors that cause deterioration of oral health-related quality of life (OHRQoL) were determined. RESULTS: Among 54 responders (25 T and 29 S), 14T and 21S kept the original dentures. Both groups were similar in ratings of satisfaction and OHRQoL (maxilla T: 80.0 S: 86.0, p = 0.36; mandibular; T: 66.1 S: 72.3, p = 0.48; OHRQoL T: 111.1 S: 108.5, p = 0.46). Irrespective of fabrication method, discomfort, chewing difficulty and esthetics were the factors that deteriorate OHRQoL (adjusted r = 0.76, p < 0.001). CONCLUSION: The results indicate that the simplified method remains more cost-efficient than the traditional method over a 10-year period. (IRB approval: A09-E71-12 B McGill University, trial registry: ClinicalTrial.org; NCT02289443).

Effect of a dietary supplement on peri-implant bone strength in a rat model of osteoporosis.

PURPOSE: Osteoporosis contributes to impaired bone regeneration and remodeling through an imbalance of osteoblastic and osteoclastic activity, and can delay peri-implant bone formation after dental implant surgery, resulting in a prolonged treatment period. It poses several difficulties for individuals with large edentulous areas, and decreases their quality of life. Consequently, prompt postoperative placement of the final prosthesis is very important clinically. Peri-implant bone formation may be enhanced by systemic approaches, such as the use of osteoporosis supplements, to promote bone metabolism. We aimed to confirm whether intake of synthetic bone mineral (SBM), a supplement developed for osteoporosis, could effectively accelerate peri-implant bone formation in a rat model of osteoporosis. METHODS: Thirty-six 7-week-old ovariectomized female Wistar rats were randomly assigned to receive a standardized diet with or without SBM (Diet with SBM group and Diet without SBM group, respectively; n=18 for both). The rats underwent implant surgery at 9 weeks of age under general anesthesia. The main outcome measures, bone mineral density (BMD) and pull-out strength of the implant from the femur, were compared at 2 and 4 weeks after implantation using the Mann-Whitney U test. RESULTS: Pull-out strength and BMD in the Diet with SBM group were significantly greater than those in the Diet without SBM group at 2 and 4 weeks after implantation. CONCLUSIONS: This study demonstrated that SBM could be effective in accelerating peri-implant bone formation in osteoporosis.

Improved Bone Micro Architecture Healing Time after Implant Surgery in an Ovariectomized Rat.

The present animal study investigated whether oral intake of synthetic bone mineral (SBM) improves peri-implant bone formation and bone micro architecture (BMA). SBM was used as an intervention experimental diet and AIN-93M was used as a control. The SBM was prepared by mixing dicalcium phosphate dihydrate (CaHPO4·2H2O) and magnesium and zinc chlorides (MgCl2 and ZnCl2, respectively), and hydrolyzed in double-distilled water containing dissolved potassium carbonate and sodium fluoride. All rats were randomly allocated into one of two groups: a control group was fed without SBM (n = 18) or an experimental group was fed with SBM (n = 18), at seven weeks old. At 9 weeks old, all rats underwent implant surgery on their femurs under general anesthesia. The implant was inserted into the insertion socket prepared at rats' femur to a depth of 2.5 mm by using a drill at 500 rpm. Nine rats in each group were randomly selected and euthanized at 2 weeks after implantation. The remaining nine rats in each group continued their diets, and were euthanized in the same manner at 4 weeks after implantation. The femur, including the implant, was removed from the body and implant was pulled out by an Instron universal testing machine. After the implant removal, BMA was evaluated by bone surface ratio (BS/BV), bone volume fraction (BV/TV), trabecular thickness (TbTh), trabecular number (TbN), trabecular star volume (Vtr), and micro-CT images. BS/BV, BV/TV, TbTh and Vtr were significantly greater in the rats were fed with SBM than those were fed without SBM at 2 and 4 weeks after implantation (P < 0.05). The present results revealed that SBM improves the peri-implant formation and BMA, prominent with trabecular bone structure. The effect of SBM to improve secondary stability of the implant, and shortening the treatment period should be investigated in the future study.