Oral function of implant-assisted removable partial dentures with magnetic attachments using short implants: A prospective study.

OBJECTIVES: This prospective study aimed to compare the oral functions of removable partial dentures (RPDs) with those of implant-assisted removable partial dentures (IARPDs) with short implants and magnetic attachments in patients with mandibular Kennedy class I and II. MATERIAL AND METHODS: Thirty participants with mandibular Kennedy class I or II and at least three distal missing teeth were recruited. Oral functions, including mixing ability, comminuting ability, maximum bite force, and occlusal contact area, were assessed for RPDs (stage 0), IARPDs with healing caps (stage 1), and IARPDs with magnetic attachments (stage 2). The implants were loaded with occlusal force in stages 1 and 2. Finally, the data of the 27 participants who completed the evaluation at stage 2 were analyzed. The Wilcoxon signed-rank test with Bonferroni correction was used to assess the differences in the oral functions among the different stages. RESULTS: The implant survival rate was 93.8%. There were significant differences in the comminuting ability and occlusal contact area between stages 0 and 2 (p < .001 and p = .036, respectively) and stages 1 and 2 (p = .003 and p = .015, respectively). Regarding the maximum bite force, there was a significant difference between stages 1 and 2 (p = .018). However, there was no significant difference in the mixing ability between the three stages. CONCLUSIONS: Within the limitations of this study, it was concluded that IARPDs in the mandible with short implants and magnetic attachments may improve oral functions.

Effect of gum-chewing exercise on maintaining and improving oral function in older adults: A pilot randomized controlled trial.

Background/purpose: Gum chewing has been found to improve oral function. Nevertheless, few randomized controlled trials have investigated the effects of gum-chewing exercises on oral function in older adults. This study aimed to examine the effect of gum-chewing exercises on oral function in older adults. Materials and methods: This was a single-blind, randomized controlled trial, conducted from November 2021 to January 2022. A total of 130 participants were divided randomly into the intervention and control groups. The intervention group was told to chew experimental gums for one month, while the control group was instructed to chew experimental tablets for one month. Maximum bite force, occlusal contact areas, oral dryness, tongue pressure, tongue and lip functions (number of times each of the following syllables is pronounced per second:/pa/,/ta/, and/ka/), masticatory function, subjective masticatory function, and gum-chewing time were measured at baseline and one month following intervention to assess outcomes. Results: One month following the intervention, tongue pressure was significantly higher in the intervention group than in the control group (P = 0.027). In the within-group comparisons, maximum bite force (P < 0.001), unstimulated saliva flow (P < 0.001), tongue and lip functions (/pa/: P < 0.001;/ta/: P < 0.001;/ka/: P < 0.001), color scale value (P = 0.019), and ΔE value (P = 0.024) were significantly increased in the intervention group. Conclusion: The results suggest that gum-chewing exercises can improve oral functions in older adults, although additional increases in masticatory load may be necessary to establish a more effective oral function training method using gum-chewing exercises in older adults.

The effect of single-implant overdentures on cognitive function in older adults: A 3-year follow-up report.

OBJECTIVE: To investigate the occurrence of mild cognitive impairment in edentulous patients up to 3 years after they received single-implant overdentures (1-IODs). METHODS: This was a follow-up study for a crossover randomized controlled trial comparing 1-IODs and conventional complete dentures, with patient satisfaction as the primary outcome. In the present study, the cognitive function of the patients, measured with the Japanese version of the Montreal cognitive assessment (MoCA-J), was evaluated as the secondary outcome at baseline and 2 months, 1 year, 2 years, and 3 years after 1-IOD placement. The total and domain (memory, executive function, visuospatial skills, language, attention, and orientation) MoCA-J scores of the patients at each timepoint were analyzed and compared. RESULTS: Twenty-two patients with edentulous mandibles received 1-IODs. Within-group comparisons revealed that the total MoCA-J scores at 1 year and 3 years after 1-IOD placement were significantly increased compared with baseline scores. Additionally, the memory domain scores at all timepoint were significantly increased compared with the baseline scores, and the executive function domain scores at the 2-month, 2-year and 3-year timepoint were significantly increased compared with the baseline scores. CONCLUSION: Patients with edentulous mandibles who underwent 1-IOD placement showed significantly improved total scores of MoCA-J after 1 year and 3 years of wearing 1-IODs. In addition, they showed significantly improved memory domain scores at 2 months, 1 year, 2 years, and 3 years after 1-IOD placement and executive function domain scores at 2 months, 2 years, and 3 years after 1-IOD placement. CLINICAL SIGNIFICANCE: The results of this study suggest that 1-IOD treatment for older adults, especially those with edentulous mandibles, may prevent cognitive decline regardless of the condition of the maxilla.

Comparison of general satisfaction, oral health-related quality of life, and patient's self-assessment between mandibular single-implant overdentures and experimental removable complete dentures: A randomized crossover clinical trial.

Objective Patient satisfaction with single-implant overdentures (1-IODs) is unclear. This randomized crossover trial aimed to compare the general satisfaction, oral health-related quality of life, and patients' self-assessment between mandibular 1-IODs and experimental removable complete dentures (eRCDs). Methods New mandibular RCDs were fabricated for 22 patients with edentulous mandibles. After adapting to the RCDs, one implant was inserted in the mandibular midline. The participants were then randomly classified into groups 1 and 2. Group 1 received IODs for the first 2 months, while group 2 used eRCDs with a non-loaded implant in the midline. After 2 months, the treatment was switched. Four validated, patient-reported dental outcome measures were assessed: general satisfaction, Japanese version of the Oral Health Impact Profile for edentulous subjects (OHIP EDENT-J), General Oral Health Assessment Index (GOHAI), and Patient's Denture Assessment (PDA). The assessments were performed at the end of the IOD- and eRCD- use periods. Results General satisfaction was significantly higher during the IOD period (p = 0.002). Significant differences were observed in all domains of the OHIP, except orofacial pain (p = 0.084). Further, the total score (p<0.001) and the scores of the physical (p<0.001) and psychosocial functioning (p = 0.001) domains of the GOHAI differed significantly. The total PDA score (p = 0.001) and the scores of the function (p = 0.004), lower denture (p = 0.002), esthetics and speech (p = 0.026), and importance (p = 0.009) domains were significantly higher during the IOD period than during the eRCD period. Conclusion General satisfaction, oral health-related quality of life, and patient self-assessment scores were significantly higher for 1-IODs than for eRCDs. Clinical significance Within the limitations of this study, we found that mandibular single-implant overdentures may be an efficient alternative to mandibular experimental removable complete dentures due to higher general satisfaction, oral health-related quality of life, and patient self-assessment scores of dentures.

In vitro study of the effect of implant position and attachment type on stress distribution of implant-assisted removable partial dentures.

Background/purpose: Implant assisted removable partial dentures (IARPDs) improved biomechanical behavior of removable partial dentures (RPDs), but information of the effect of attachment type and implant position is limited. This study aimed to investigate the effect of implant position and attachment type on the stress distribution of IARPDs. Material and methods: Four implants, 10 mm in length and 4.1 mm in diameter, were bilaterally placed close to first premolar and second molar regions of a mandibular Kennedy class I model having artificial dentition from canine to canine, vertical to the occlusal plane. Five IARPDs were fabricated to accommodate locator and magnetic attachments. Strain gauges were placed on the model surface to measure the strain around implants during loading. Unilateral vertical loading was applied to the right first molar area with magnitude of 120 N and crosshead speed of 10 mm/min. Measurements were recorded under following conditions: premolar IARPDs with locator or magnetic attachments, molar IARPDs with locator or magnetic attachments. Two-way multiple analysis of variance was performed to compare the maximum principal strain (MPS) around the implants with a significance level of 0.05. Results: Implant position had significant effect on the MPS of IARPD on loading and nonloading sides while attachment type only significant on nonloading side. Molar implants showed larger MPS than premolar implants with both locator and magnetic attachments during unilateral loading. Conclusion: The stress distribution of the IARPD is significantly affected by implant position wherein anteriorly placed implants exhibit lower MPS than relatively posteriorly placed implants.

Masticatory performances and maximum occlusal forces of immediate and conventional loaded two-implant supported overdentures retained by magnetic attachments: preliminary study of randomized controlled clinical trial.

BACKGROUND: The appropriate loading protocol to improve masticatory performance (MP) is still unclear in elderly patients and two-implant overdentures (2-IODs) wearers. This study aimed to compare the long-term MP and maximum occlusal force of immediate loading (IL) and conventional loading (CL) of 2-IODs retained by magnetic attachments. Nineteen edentulous patients were randomly assigned to either an IL (n=10) or CL group (n = 9). In the IL group, the implant was loaded on the same day as insertion, whereas it was loaded 3 months after insertion in the CL group. Magnetic attachments were used to retain all overdentures to the implants. MP, measured by a piece of color-changeable chewing gum and a gummy jelly test, and maximum occlusal force, measured using an occlusal force measuring device, were assessed in both groups at baseline and at 3-, 4-, and 5-year follow-ups. RESULTS: No significant differences were observed in the MP and the maximum occlusal force between the IL and CL groups at any time point. However, a significantly higher MP was observed at the 3-year time point in the IL group (P = 0.036). The maximum occlusal force revealed a significant correlation with MP, both with the color-changeable chewing gum and gummy jelly at 5 years. CONCLUSION: After long-term observation, no significant differences in MP and maximum occlusal force were observed between the IL and CL groups. However, compared to pre-implant insertion of the complete denture, the MP in the IL group significantly improved at 3 years. Furthermore, the maximum occlusal force was significantly correlated with MP at 5 years. TRIAL REGISTRATION: UMIN, UMIN000009889 . Registered on 28 January 2013.

Study of sustained blood pressure-lowering effect of azelnidipine guided by self-measured morning and evening home blood pressure: subgroup analysis of the At-HOME study.

BACKGROUND: Morning hypertension is a risk factor for cardiovascular and cerebrovascular events, and consequently diagnosis and control of morning hypertension are considered very important. We previously reported the results of the Azelnidipine Treatment for Hypertension Open-label Monitoring in the Early morning (At-HOME) Study, which indicated that azelnidipine effectively controlled morning hypertension. OBJECTIVES: The objective of this At-HOME subgroup analysis was to evaluate the sustained blood pressure (BP)-lowering effect of azelnidipine, using mean morning and evening systolic BP [ME average] and morning systolic BP minus evening systolic BP (ME difference). METHODS: We analyzed the self-measured home BP data (measured in the morning and at bedtime) from this 16-week prospective observational study to clarify the effect of morning dosing of azelnidipine (mean [± standard deviation] maximum dose 14.3 ± 3.6 mg/day). A subgroup of patients from the At-HOME Study who had an evening home BP measurement within 28 days prior to the baseline date were used for efficacy analysis (n = 2,546; mean age, 65.1 years; female, 53.6 %). RESULTS: Home systolic BP/diastolic BP levels in the morning and evening were significantly lowered (p < 0.0001) by -19.4 ± 17.1/-10.3 ± 10.6 and -16.9 ± 17.0/-9.4 ± 10.6 mmHg, respectively. Home pulse rates in the morning and evening were also significantly lowered (p < 0.0001) by -3.5 ± 7.8 and -3.5 ± 7.3 beats/min, respectively. At baseline, patients whose ME average was ≥135 mmHg and whose ME difference was ≥15 mmHg (defined as morning-predominant hypertension) accounted for 20.4 % of the study population. However, at the end of the study, the number of such patients was significantly reduced to 7.9 % (p < 0.0001). Patients whose ME average was ≥135 mmHg and whose ME difference was <15 mmHg (defined as sustained hypertension) accounted for 71.1 % of the study population at baseline. This was reduced significantly to 42.8 % at the end of the study (p < 0.0001). ME average decreased significantly from 153.8 ± 15.5 mmHg to 135.6 ± 11.9 mmHg, and ME difference also decreased significantly from 6.7 ± 13.1 mmHg to 4.7 ± 10.8 mmHg (both p < 0.0001). CONCLUSION: These results suggest that azelnidipine improved morning hypertension with its sustained BP-lowering effect.