Gonial angle and late implant loss: A retrospective clinical study.

PURPOSE: Occlusal overload can cause late implant loss. However, whether the magnitude of the occlusal force is a risk factor for late implant loss remains unclear. Thus, this clinical study aimed to determine the relationship between the gonial angle (GoA), which is associated with the magnitude of occlusal force, and late implant loss. METHODS: All implants with fixed prostheses placed at the Niigata University Hospital between April 2006 and August 2019 were included in this retrospective study. The implants with and without late loss were compared. Relevant variables, including smoking habits, diabetes mellitus status, remaining dentition, implant length and diameter, prosthesis design, retention systems, splinting, and GoA were assessed. Log-rank test and Cox proportional hazards regression analysis were used to estimate the adjusted hazard ratio (aHR) and to calculate the corresponding 95% confidence intervals (CI) for late implant loss. RESULTS: A total of 919 patients (349 men and 570 women) with 2512 implants were included in this study. Cox proportional hazards regression analysis revealed that a 10° decrease in the GoA (aHR, 1.588; 95% CI, 1.115-1.766; P = 0.010), smoking habits (aHR, 3.909; 95% CI, 2.131-7.168; P < 0.001), and male sex (aHR, 2.584; 95% CI, 1.376-4.850; P = 0.003) were significantly associated with late implant loss. CONCLUSIONS: Within the limitations of this retrospective study of 2512 implants, smaller GoA, smoking habits, and male sex were risk factors for late implant loss.

Investigation of orthognathic surgery indicators-combination with index of orthognathic functional treatment needs (IOFTN) and maxillofacial morphometric analysis.

PURPOSE: The aim of this retrospective study was to determine orthognathic surgery indicators for Japanese patients with jaw deformities using both Index of Orthognathic Functional Treatment Needs (IOFTN) and maxillofacial morphometric analysis. SUBJECTS AND METHODS: The subjects were 89 patients treated with orthognathic surgery and 92 patients treated with orthodontic treatment alone, and were classified as class I, II, or III according to the ANB angle. Based on the results for IOFTN and the results of cephalometric analysis, the indication criteria for orthognathic surgery were examined. RESULTS: In IOFTN analysis, none of patients in the orthognathic surgery group were classified as category 1 or 2, while 48% of the patients in the orthodontic treatment group were classified as category 4 or 5. The results of the cephalometric analysis of patients in classified categories 4 and 5 showed that the orthognathic surgery group had significantly greater lateral mandibular deviation in Class I cases, significantly more severe degree of mandibular retrusion in Class II cases, and significantly more severe degree of mandibular prognathism in Class III cases. The results of the logistic regression analysis showed that IOFTN was a common variable as an indication criterion for orthognathic surgery, and several different variables were also selected from the cephalometric measurements in each group. CONCLUSION: IOFTN is a highly sensitive and useful indicator as a criterion for orthognathic surgery. However, in the choice of treatment strategy, maxillofacial morphometric analyses and the patient's desired goal are important.

Association of Hyper-Low-Density Lipoprotein and Hypo-High-Density Lipoprotein Cholesterolemia with Low Saliva Flow Rates in Japanese Community-Dwelling Elders

Abstract Introduction The associations of low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein (HDL-C) with reduced saliva flow rates have not been previously reported. Objective The present study aimed to assess the association of cholesterolemia with reduced saliva flow rates in community-dwelling elderly subjects. Methods The present study analyzed 342 participants (170 males and 172 females aged between 78 and 79 years old). Unstimulated salivary flow rate (USFR) was assessed using a cotton roll method. Low-USFR was defined as 0.10 g/30 seconds. Stimulated salivary flow rate (SSFR) was assessed by having the participants chew tasteless gum for 3minutes. Low-SSFR was defined as 1.0 mL/minute. Blood samples were collected for the measurement of LDL-C, HDL-C, rheumatoid factor, hemoglobin A1c, and creatinine. To assess depression, the General Health Questionnaire 30 was used. A standardized questionnaire was completed, covering the current and previous medications of the participants and smoking status. We stratified the serum LDL-C levels of the participants as normal, moderate or severe hyper-LDL cholesterolemia and serum HDL-C levels as normal or hypo-HDL cholesterolemia. Multivariate logistic regression models were established and low-USFR or low-SSFR were set as dependent variables in the aforementioned models. Results After controlling for the effects of the other variables, the odds ratios (ORs) (95% confidence intervals [CIs]) for low-USFR were 2.25 (1.10-4.61) for moderate and 5.69 (1.55-20.8) for severe hyper-LDL cholesterolemia, while that of hypo-HDL cholesterolemia was 3.40 (1.33-8.69). Severe hyper-LDL cholesterolemia was also associated with low-SSFR with an OR of 3.89 (1.39-10.88). Conclusion Elderly patients with cholesterolemia have a risk of reduced salivary flow rate.

Masseter muscle cross-sectional area and late implant failure: A case-control study.

INTRODUCTION: Occlusal overload is considered to be one of the causes of late implant failure. However, it is unclear whether the magnitude of the patient's occlusal force is a risk factor for late implant failure. PURPOSE: This case-control study aimed to clarify the association between the cross-sectional area (CSA) of the masseter muscle and late implant failure. METHODS: This case-control study was limited to implant-supported fixed prostheses. We compared cases with at least one late implant failure (n = 25 patients) to controls (n = 82 patients) without implant failure. Patients were matched by age, sex, year of surgery, jaw and tooth type, and bone graft. Log-rank and Cox proportional hazard regression analyses were used to identify possible risk factors for late implant failure. RESULTS: The incidence of late implant failure was significantly associated with masseter muscle CSA ≥504.5 mm2 (hazard ratio: 4.43; 95% CI: 1.82-10.79; p < 0.01). CONCLUSION: Higher masseter muscle CSA increases the risk of late implant failure.

Association of Hyper-Low-Density Lipoprotein and Hypo-High-Density Lipoprotein Cholesterolemia with Low Saliva Flow Rates in Japanese Community-Dwelling Elders.

Introduction The associations of low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein (HDL-C) with reduced saliva flow rates have not been previously reported. Objective The present study aimed to assess the association of cholesterolemia with reduced saliva flow rates in community-dwelling elderly subjects. Methods The present study analyzed 342 participants (170 males and 172 females aged between 78 and 79 years old). Unstimulated salivary flow rate (USFR) was assessed using a cotton roll method. Low-USFR was defined as 0.10 g/30 seconds. Stimulated salivary flow rate (SSFR) was assessed by having the participants chew tasteless gum for 3 minutes. Low-SSFR was defined as 1.0 mL/minute. Blood samples were collected for the measurement of LDL-C, HDL-C, rheumatoid factor, hemoglobin A1c, and creatinine. To assess depression, the General Health Questionnaire 30 was used. A standardized questionnaire was completed, covering the current and previous medications of the participants and smoking status. We stratified the serum LDL-C levels of the participants as normal, moderate or severe hyper-LDL cholesterolemia and serum HDL-C levels as normal or hypo-HDL cholesterolemia. Multivariate logistic regression models were established and low-USFR or low-SSFR were set as dependent variables in the aforementioned models. Results After controlling for the effects of the other variables, the odds ratios (ORs) (95% confidence intervals [CIs]) for low-USFR were 2.25 (1.10-4.61) for moderate and 5.69 (1.55-20.8) for severe hyper-LDL cholesterolemia, while that of hypo-HDL cholesterolemia was 3.40 (1.33-8.69). Severe hyper-LDL cholesterolemia was also associated with low-SSFR with an OR of 3.89 (1.39-10.88). Conclusion Elderly patients with cholesterolemia have a risk of reduced salivary flow rate.

Characteristics of medication-induced xerostomia and effect of treatment.

OBJECTIVE: Side-effects of medications cause xerostomia. There have been cases where a medication has been discontinued owing to its severe side-effects. Therefore, the xerostomia must be treated to ensure that the primary disease is managed effectively. This study analyzed the actual status of patients with medication-induced xerostomia and investigates factors associated with its improvement. METHODS: This study assessed 490 patients diagnosed with medication-induced xerostomia who had an unstimulated salivary flow of ≤0.1 mL/min and received treatment for xerostomia at a xerostomia clinic. Patient age, sex, medical history, medications used, disease duration of xerostomia, and psychological disorders were recorded. The anticholinergic burden was assessed using the Anticholinergic Cognitive Burden scale. The unstimulated salivary flow was measured by the spitting method. According to their symptoms and diagnoses, the patients were introduced to oral lubricants, instructed on how to perform massage, and prescribed Japanese herbal medicines, and sialogogues. Factors associated with the subjective improvement of xerostomia and objective changes in the salivary flow rate were recorded at six months. RESULTS: Xerostomia improved in 338 patients (75.3%). The improvement rate was significantly lower in patients with psychiatric disorders (63.6%) (P = 0.009). The improvement rate decreased as more anticholinergics were used (P = 0.018). However, xerostomia improved in approximately 60% of patients receiving three or more anticholinergics. The unstimulated salivary flow increased significantly more in patients who reported an improvement of xerostomia (0.033±0.053 mL/min) than in those who reported no improvement (0.013±0.02 mL/min) (P = 0.025). CONCLUSION: Xerostomia treatment improved oral dryness in 75.3% of patients receiving xerogenic medications in this study. If xerostomia due to side-effects of medications can be improved by treatment, it will greatly contribute to the quality of life of patients with xerogenic medications and may reduce the number of patients who discontinue medications.

Oral Health and Nutritional Intake in Community-Dwelling 90-Year-Old Japanese People: A Cross-Sectional Study.

INTRODUCTION: This study aimed to determine the relationship between dentition, mastication, salivation and nutritional intake in 90-year-old Japanese people. METHODS: This cross-sectional study included 84 participants (39 men and 45 women) aged 90 years. We used questionnaires to collect demographic information, smoking status, nutritional intake and higher-level functional capacity. Nutritional intake was assessed using the validated Brief-Type Self-Administered Diet History Questionnaire, and higher-level functional capacity was assessed using the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) questionnaire. Oral examinations, masticatory performance tests, stimulated salivary flow rate (SSF) tests, blood tests, blood pressure tests and body mass index (BMI) assessments were conducted. Univariable and multivariable linear regression analyses were performed. RESULTS: Multivariable linear regression analyses adjusted for sex, education, TMIG-IC and BMI ≤20 kg/m2 showed that participants with masticatory performance <173 mg/dL had lower intake of folic acid and vitamin A than those with masticatory performance ≥173 mg/dL. SSF was positively associated with intake of vitamin A. The number of teeth was positively associated with the intake of ß-carotene. With smaller effect sizes, masticatory performance, SSF and number of teeth were also associated with the intake of various micronutrients and carbohydrates. CONCLUSION: Lower masticatory performance, lower SSF and fewer teeth were associated with a lower intake of several micronutrients, such as vitamin A, ß-carotene and folic acids, in Japanese individuals of advanced age. Oral health practitioners should pay careful attention to the nutritional intake of older people with poor mastication, dry mouth and severe tooth loss.

Clinical and Microbial Evaluation of Dental Caries Status and Associated Factors Among Primary Schoolchildren in Myanmar: A Cross-Sectional Study.

The study aimed to investigate the prevalence and associated factors of dental caries on primary teeth and to evaluate the cariogenic bacteria in dental plaque and saliva among Myanmar schoolchildren. A cross-sectional study was undertaken among 264 schoolchildren from three primary schools in the urban area of Yangon city in 2019. Clinical oral examinations, caries risk tests, and questionnaire surveys were conducted. Overall caries prevalence was 84.1% with a mean decayed, missing, filled primary teeth (dmft) count of 5.84 ± 4.57. Children's caries experience and debris scores were significantly associated with their bacteria score level. Father's occupation was significantly associated with caries prevalence (P = .024) and dmft (P = .021). Father's occupation, snack types, habit of eating sweet food combinations, drink types, and debris score were five significant predictors of dental caries in our study. Dental caries is currently a public health problem among Myanmar children. Caries experience and oral hygiene status were strongly influenced by cariogenic bacteria.

Effects of Interval Walking Training on Oral Health Status in Middle-Aged and Older Adults: A Case-Control Study.

The purpose of this study was to determine the effect of walking training "Interval Walking Training (IWT)" on oral health status. Participants were divided into two groups: an exercise intervention group and a non-intervention group (control). The intervention group consisted of 59 subjects (20 males, 39 females) aged 50 years or older who participated in the IWT program in Matsumoto from 2019 to April 2022. The control group consisted of 33 subjects (14 males and 19 females) aged 50 years or older who have visited Niigata University Medical and Dental Hospital and agreed to participate in the study. The intervention group underwent walking training (interval walking training) for at least 5-6 months. The walking training consisted of five sets of fast walking above 70% peak aerobic capacity for walking (VO2peak) for 3 min, followed by 3 min of slow walking at ~40% VO2 peak per day for more than four days/week. The oral health status was evaluated for the number of teeth, occlusal force, salivary occult blood, masticatory performance, and tongue pressure. A total of 57 participants were analyzed in the intervention group (18 males and 39 females, age: 66.7 ± 0.8 (mean ± S.E.) years) and 33 participants in the control group (14 males and 19 females, age: 74.5 ± 1.1 (mean ± S.E.) years). There were no significant differences in gender, salivary occult blood, tongue pressure, masticatory performance, or occlusal force between the two groups at the start of the intervention (p = 0.36, p = 0.48, p = 0.42, p = 0.58, and p = 0.08, respectively by unpaired t-test or χ2 test). On the other hand, there were significant differences in age and BMI, with a trend toward lower age and higher BMI in the intervention group (p < 0.001 and p < 0.001, respectively, by unpaired t-test). In terms of rate of change, the intervention group showed a significant increase in occlusal force (F = 4.5, p = 0.04, ANCOVA) and a significant decrease in BMI (F = 7.3, p = 0.009, ANCOVA). No significant differences were observed in the other measured items. It was found that walking training in both middle-aged and older people does not only affect the physical aspect of weight loss but may help maintain and improve the occlusal force.

Examination of factors affecting condylar bone changes following surgical-orthodontic treatment.

OBJECTIVE: To identify factors affecting condylar bone changes following surgical-orthodontic treatment. METHODS: A total of 200 patients with dentofacial deformities were classified into skeletal Classes I, II, and skeletal Class III groups consisting of 61 and 139 subjects, respectively. Temporomandibular joints (TMJs) were evaluated using clinical findings and computed tomography images before treatment, immediately before surgery, and 6 months after surgery. RESULTS: Condylar bone changes occurred at a significantly higher rate after surgery in both groups. Factors related to condylar bone changes following surgical-orthodontic treatment included skeletal Class I or II, disc displacement, and condylar bone changes before treatment. There were three cases with condylar bone changes after surgery that were diagnosed with condylar resorption and skeletal Class II and anterior disc displacement before surgery. CONCLUSION: Condylar resorption could occur when the load on the condyle increases after orthognathic surgery and exceeds the permissible limit.

Effect of Locally Delivered Minocycline on the Profile of Subgingival Bacterial Genera in Patients with Periodontitis: A Prospective Pilot Study.

This prospective pilot study aimed to evaluate the effect of minocycline-HCl ointment (MO), locally delivered as an adjunct to scaling and root planing (SRP), on subgingival microflora. A total of 59 periodontitis patients received SRP as an initial periodontal therapy. In the selected periodontal pockets with probing depths (PD) of 6−9 mm, the sites that exhibited a positive reaction following a bacterial test using an immunochromatographic device were subsequently treated with MO (SRP + MO group, n = 25). No additional treatment was performed at sites showing a negative reaction (SRP group, n = 34). In addition to subgingival plaque sampling, measurement of clinical parameters including PD, clinical attachment level (CAL), bleeding on probing (BOP), plaque index and gingival index (GI) were performed at baseline and 4 weeks after the initial periodontal therapy. The subgingival microflora were assessed by terminal restriction fragment-length polymorphism analysis. Relative to baseline values, the mean scores for PD-, CAL-, BOP-, and GI-sampled sites were significantly decreased post treatment in both groups (p < 0.01). The intra-comparisons showed a significant decrease in the counts of the genera Eubacterium, Parvimonas, Filifactor, Veillonella, Fusobacterium, Porphyromonas, Prevotella, and unknown species in the SRP + MO group (p < 0.05). Inter-comparisons indicated a significant decrease in the genera Veillonella in the SRP + MO group (p = 0.01). Combination therapy of SRP and local MO induced a change in the subgingival microbial community: particularly, the number of Veillonella spp. was markedly reduced.

Anti-caries and Anti-microbial Effects of School-based Fluoride Programs in Myanmar Schoolchildren.

PURPOSE: To investigate the anti-caries effects of the school-based fluoride varnish (FV) application at 3-month intervals and ?weekly fluoride mouthrins?ing? (FMR) ?on primary teeth and to evaluate the anti-microbial effects of FV or FMR on cariogenic bacteria among Myanmar children. MATERIALS AND METHODS: A 6-month interventional study was conducted on 234 schoolchildren who were divided into three groups: group A received FV application at 3-month intervals, group B received weekly FMR,? and group C received no fluoride application. A clinical oral examination and caries risk tests were performed at baseline and the 6-month follow-up. RESULTS: Caries prevalence and ?the debris score did not change statistically significantly from baseline to the 6-month follow-up in all groups, whereas the dmfs score statistically significantly increased in group C (p = 0.001). The plaque and saliva scores of Dentocult SM statistically significantly decreased in group A (p = 0.049 and p = 0.006), but those scores statistically significantly increased in group C (p = 0.001 and p = 0.014) after six months. On the other hand, no statistically significant changes were observed in group B. Although the Cariostat scores decreased from baseline to the 6-month follow-up in group A and group B, but increased in group C, no statistically significant differences were observed in any of the groups. CONCLUSION: Better anti-microbial effects were obtained for children who received FV application than for those who received FMR, but no statistically significant difference existed between the anti-caries effects of these two approaches.

Factors associated with xerostomia in perimenopausal women.

OBJECTIVES: Various oral symptoms, including xerostomia and burning mouth syndrome, may occur in menopausal women. These symptoms reduce quality of life (QOL). However, the actual condition of xerostomia after menopause is not clear. The purpose of this study was to reveal the factors associated with xerostomia in perimenopausal women. METHODS: Participants included 118 outpatients (mean age, 49.9 ± 3.2 years; range, 45-55 years) at a department of gynecology in Japan. Information was collected concerning age, medical history, medications, menstrual status, and history of treatment for climacteric symptoms. Oral symptoms, including xerostomia were evaluated with a 3-point scale. The climacteric symptom checklist for Japanese women and 36-Item Short-Form Health were used to evaluate climacteric symptoms and QOL, respectively. In addition, the volume of unstimulated saliva, oral moisture, salivary α-amylase, chromogranin A, and 17-ß estradiol were measured. RESULTS: Higher age, the total number of medications, psychotropic drug, hormone replacement therapy, treatment for climacteric symptoms, sticky mouth, burning sensation of tongue, dryness of nose and 14 of the 21 climacteric symptoms significantly affected xerostomia. In addition, treatment for climacteric symptoms, fall asleep but often awake at night, headaches and dryness of nose were significantly associated with xerostomia. In conclusion, xerostomia is closely associated to factors such as treatment for climacteric symptoms and certain menopausal symptoms, and it may be related to QOL in perimenopausal women.

Efficacy of Erbium:YAG Laser for Regenerative Surgical Treatment of Peri-implantitis: Clinical, Microbiological, and Biomarker Analyses.

This paper reports on a study undertaken to ascertain the efficacy of the erbium:YAG laser (EYL) for peri-implantitis treatment. A total of 12 patients with bone loss resulting from peri-implantitis were involved in this study. The treatment protocol consisted of using the EYL for implant surface debridement and deproteinized bovine bone mineral (DBBM) for bone grafting. The following parameters were analyzed: probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), bone levels (BLs), and the lipopolysaccharide levels before and after debridement with the EYL. This study found a statistically significant improvement in PPD, CAL, BOP, and BL at 3 and 12 months postoperative. Furthermore, a statistically significant decrease in implant-surface LPS levels was observed following debridement with the EYL. These findings show that using the EYL for debridement in peri-implantitis cases is effective in decreasing LPS levels. Moreover, after partial reconstruction with DBBM grafting, BLs were restored for at least 12 months. It was shown in one case that BLs had remained stable over 6 years, which also attests to the efficacy of this treatment. The combined use of EYL and DBBM could be effective for regenerative surgical peri-implantitis treatment.

Interaction between and impact of IL-6 genotype and alpha-tocopherol levels on periodontal condition in aging individuals.

BACKGROUND AND OBJECTIVES: Few studies have assessed the possible interaction between and impact of IL-6 variants and serum α-tocopherol levels on periodontal condition in older individuals. Here, we assessed the relationship between IL-6 variants and serum α-tocopherol levels on periodontal condition by considering effect modification. MATERIAL AND METHODS: Among the study participants, 359 who were 71 years of age underwent a dental examination, biochemical analysis, and interview. After dividing the participants into tertiles based on serum α-tocopherol levels, we conducted Poisson regression analysis to compare the prevalence rate ratio (PRR) for periodontal disease markers with the IL-6 genotype (rs1800796) based on each tertile adjusted by the number of teeth present (offset). RESULTS: The PRRs of the IL-6 genotype for periodontal condition (probing pocket depth [PPD], clinical attachment level [CAL], and bleeding on probing [BOP]) which were adjusted by the number of teeth present (offset) were 1.17 (P < .001), 1.37 (P < .001), and 1.08 (P = .048), respectively. In addition, a significant association was found between the reciprocal number of PRRs of the IL-6 genotype and three serum α-tocopherol levels. The adjusted PRRs (± standard error) of the IL-6 genotypes for PPD were 0.48 (0.12) for the first group (P < .001), 1.54 (0.04) for the second group (P < .001), and 2.11 (0.03) for the third group (P < .001); similar tendencies were seen for CAL and BOP. CONCLUSION: The results of this study suggest a potential association between the IL-6 genotype and periodontal condition in relation to serum antioxidant concentrations.

Reducing bacterial counts around the abutment following professional mechanical plaque removal at the implant bridge: A randomized crossover comparison of removing or not removing the superstructure.

PURPOSE: The purpose of this study was to determine whether removing the superstructure of the implant bridge in cases of full-arch implant restorations for edentulous atrophic arches at the abutment level during professional mechanical plaque removal (PMPR) affects bacterial counts. METHODS: This crossover clinical trial included 20 patients who received screw-retained prostheses at the abutment level. Patients were randomly assigned to two groups and received PMPR with or without removal of the superstructure. After a three-month washout period, the type of treatment was reversed between the groups. Bacterial counts around the cylinder and abutment were measured and compared before and after PMPR. RESULTS: Bacterial numbers around the cylinder and abutment were significantly reduced after PMPR as compared with before PMPR regardless of whether the superstructure was removed (p <0.05). However the ratio of subjects with bacteria at 1.0 × 105 colony forming unit/ml (cfu/ml) or more after PMPR was significantly higher when the superstructure was not removed (p < 0.05). Among patients with bacterial counts of less than 10 × 105 cfu/ml, bacterial loads were reduced to less than 1.0 × 105 cfu/ml even when superstructures were not removed. Among patients with bacterial load of >10 × 105 cfu/ml, bacterial numbers were not reduced to <1.0 × 105 cfu/ml when PMPR was performed without removing the superstructure. CONCLUSIONS: Removal of the superstructure in cases of full-arch implant restorations for edentulous atrophic arches during PMPR reduces bacterial numbers around the implant bridge at the abutment level.

Radiological imaging features of the salivary glands in xerostomia induced by an immune checkpoint inhibitor.

The clinical features of xerostomia induced by immune checkpoint inhibitors (ICI) are similar to those of Sjögren's syndrome (SS), whereas the immunohistological and serological features are known to differ from those of SS. However, the radiologic imaging features of salivary glands are not yet well known. We report a case of a 56-year-old male patient diagnosed with ICI-induced xerostomia. The patient underwent various imaging examinations to investigate the condition of the salivary glands, which indicated the following: (1) less specific findings on contrast-enhanced computed tomography, (2) mixed with intermediate and low signal intensity on both T1-weighted and fat-suppressed T2-weighted magnetic resonance imaging and poor "salt and pepper" appearance on magnetic resonance sialography, and (3) multiple ovoid hypoechoic areas with hyperechoic bands without acute sialadenitis on ultrasound. These radiologic imaging findings suggested remarkable lymphocyte infiltration, which could be a characteristic of ICI-induced xerostomia.

Interaction between beta-3 adrenergic receptor genotype and environmental factors on periodontal progression.

OBJECTIVES: The purpose of this longitudinal study was to evaluate the relationship between beta-3 adrenergic receptor polymorphism and environmental factors such as smoking on periodontal disease by considering effect modification. MATERIALS AND METHODS: A total of 294 subjects who participated in all follow-up surveys over the 6-year study period were analysed. After dividing subjects into tertiles according to the number of years exposed to smoking, we conducted Poisson regression analysis to compare the incidence rate ratio (IRR) for periodontal disease events during the 6-year study period with beta-3 adrenergic receptor genotype (1: Arg allele carriers, 2: Arg allele non-carriers) for each tertile adjusted for other four variables. RESULTS: The number of years exposed to smoking (mean ± standard deviation) for the 1st, 2nd and 3rd tertiles was 0 ± 0, 20.1 ± 9.1 and 45.3 ± 7.7 years, respectively. The IRRs ± SE were 0.89 ± 0.08 (p = 0.218) for the 1st tertile, 1.93 ± 0.36 (p < 0.001) for the 2nd tertile and 2.56 ± 0.23 (p < 0.001) for the 3rd tertile. CONCLUSION: There was a clear dose-response relationship between beta-3 adrenergic receptor genotype and periodontal disease progression based on the number of years exposed to smoking.

Effectiveness of an erbium-doped: yttrium, aluminum and garnet laser for treatment of peri-implant disease: Clinical, microbiological, and biochemical marker analyses.

BACKGROUND: The effectiveness of an erbium-doped: yttrium, aluminum and garnet (Er: YAG) laser (EYL) for the treatment of peri-implant disease (PID) remains unclear. The aim of this study was to compare non-surgical EYL therapy for PID with locally delivered minocycline hydrochloride (MC) ointment therapy by evaluating clinical, microbiological, and biochemical markers. MATERIAL AND METHODS: Thirty-seven patients with PID were randomly assigned to either the EYL group (n = 18) or the MC group (n = 19). The clinical, microbiological, and biochemical markers at baseline and at 1 and 3 months after treatment were compared between the two groups. Subgingival plaque and peri-implant crevicular fluid (PICF) were collected from the diseased pockets. RESULTS: In the EYL group, probing pocket depth (PPD) was significantly decreased after treatment when compared with baseline. On the other hand, in the MC group, there was no significant decrease in PPD after treatment. Specific bacteria associated with PID were not determined. The counts of both Gram-positive and -negative species did not significantly decrease in the EYL group at 3 months after treatment. In the MC group, the counts of almost all bacterial species were significantly decreased after treatment. Biochemical marker analysis of PICF revealed significantly lower levels of metalloproteinase (MMP)-9 in the EYL group, as compared with the MC group at 3 months after treatment (p= 0.009). CONCLUSIONS: Non-surgical therapy with an EYL for PID was clinically effective, with decreased MMP-9 levels in PICF, which may lead to reduced peri-implant tissue destruction. Key words:Er: YAG laser; peri-implant disease; biomarker; peri-implant crevicular fluid.

Effects of Antimicrobial Photodynamic Therapy and Local Administration of Minocycline on Clinical, Microbiological, and Inflammatory Markers of Periodontal Pockets: A Pilot Study.

OBJECTIVE: We evaluated the efficacies of antimicrobial photodynamic therapy (aPDT) and minocycline ointment (MO) on clinical and bacteriological markers and the local host inflammatory response. MATERIALS AND METHODS: A total of 30 patients with chronic periodontitis were randomly assigned to two groups. Selected periodontal pockets (probing depth 5-7 mm with bleeding on probing) were treated with aPDT or MO. Measurements of clinical parameters and the collection of gingival crevicular fluid (GCF) and subgingival plaque were performed at baseline, and at 1 and 4 weeks after treatment. Quantification of periodontopathic bacteria in the sulcus and a multiplex bead immunoassay of ten inflammatory cytokines in the GCF were performed. RESULTS: Local MO administration exhibited a significant decrease in scores for clinical parameters (P < 0.01) and a significant reduction in bacterial counts (P < 0.01) and interleukin-1ß and interferon-γ levels at 1 and 4 weeks after treatment (P < 0.01). No significant changes were observed in the aPDT group, except in clinical parameters. CONCLUSIONS: Although our study had some limitations, we found that while local administration of MO may slightly help to improve clinical, microbiological, and crevicular cytokine levels in periodontal pockets, aPDT did not show any effects. This trial is registered with the UMIN Clinical Trials Registry UMIN000013376.