DA-9805, a Herbal Mixture, Restores Motor Manifestations in 6-Hydroxydopamine-induced Parkinson's Disease Mouse Model by Regulating Striatal Dopamine and Acetylcholine Levels.

Loss of dopamine (DA) is one of the primary features of Parkinson's disease (PD); however, imbalances of non-dopaminergic neurotransmitters significantly contribute to the disabilities noted in advanced PD patients. DA-9805 is the ethanolic extraction of the root bark of Paeonia × suffruticosa Andrews (Paeoniaceae), the root of Angelica dahurica (Hoffm.) Benth. and Hook.f. ex Franch. and Sav. (Apiaceae) and the root of Bupleurum falcatum L. (Apiaceae), which have been widely utilized as an enhancer of motor function in East Asia. This study aimed to investigate whether DA-9805 modified motor dysfunctions and imbalances associated with DA and other neurotransmitters in a 6-hydroxydopamine-induced PD mouse. We confirmed the expressions of proteins related with neurotransmissions in the striatum. In addition, we measured the striatal neurotransmitters using HPLC and analyzed their correlation. DA-9805 significantly improved motor impairments and restored the altered levels of neurotransmitters in the striatum. Moreover, DA-9805 improved the altered expressions of tyrosine hydroxylase (TH), DA transporter, and choline acetyltransferase (ChAT) in the ipsilateral part of mouse striatum or SNpc, which implies the neuroprotection. We also found that the level of striatal acetylcholine (Ach) has the moderate negative correlation with motor functions and TH expression in the SNpc. This study indicates that DA-9805 restores motor dysfunctions by normalizing the increased levels of striatal Ach via modulating DA transmission and ChAT expressions as well as its neuroprotective effects.

Improved Attitude and Heading Accuracy with Double Quaternion Parameters Estimation and Magnetic Disturbance Rejection.

The use of unmanned aerial vehicle (UAV) applications has grown rapidly over the past decade with the introduction of low-cost microelectromechanical system (MEMS)-based sensors that measure angular velocity, gravity, and magnetic field, which are important for an object orientation determination. However, the use of low-cost sensors has also been limited because their readings are easily distorted by unwanted internal and/or external noise signals such as environmental magnetic disturbance, which lead to errors in attitude and heading estimation results. In an extended Kalman filter (EKF) process, this study proposes a method for mitigating the effect of magnetic disturbance on attitude determination by using a double quaternion parameters for representation of orientation states, which decouples the magnetometer from attitude computation. Additionally, an online measurement error covariance matrix tuning system was implemented to reject the impact of magnetic disturbance on the heading estimation. Simulation and experimental tests were conducted to verify the performance of the proposed methods in resolving the magnetic noise effect on attitude and heading. The results showed that the proposed method performed better than complimentary, gradient descent, and single quaternion-based EKF.

Protective effects of DA-9805 on dopaminergic neurons against 6-hydroxydopamine-induced neurotoxicity in the models of Parkinson's disease.

With the elderly population rapidly growing, the prevalence of Parkinson's disease (PD) is quickly increasing because neurodegenerative disorders are usually late-onset. Herbal medicines and formula are adjuvant therapies of conventional PD agents, which result in serious side effects with long-term use. This study evaluated the neuroprotective effects of DA-9805, a standardized herbal formula that consists of an ethanolic extract of Moutan Cortex Radix, Angelica Dahuricae Radix, and Bupleuri Radix against 6-hydroxydopamine (6-OHDA)-induced cytotoxicity in vitro and in vivo. In PC12 cells, DA-9805 at concentrations of 1 and 10 µg/mL ameliorated cell viability, which was reduced by 6-OHDA. In addition, DA-9805 activated the extracellular-regulated kinase-nuclear transcription factor-erythroid 2-related factor 2 pathway, subsequently stimulating antioxidative enzymes such as NAD(P)H:quinone oxidoreductase 1 and catalase and suppressing apoptosis. Furthermore, DA-9805 prevented 6-OHDA-induced movement impairment, as well as a decrease of dopaminergic neurons and dopamine transmission in rodents. Taken together, these results suggest that the mixed herbal formula DA-9805 may be a pharmaceutical agent for preventing or improving PD.

Triple herbal extract DA-9805 exerts a neuroprotective effect via amelioration of mitochondrial damage in experimental models of Parkinson's disease.

Moutan cortex, Angelica Dahurica root, and Bupleurum root are traditional herbal medicines used in Asian countries to treat various diseases caused by oxidative stress or inflammation. Parkinson's disease (PD) has been associated with mitochondrial dysfunction, but no effective treatment for mitochondrial dysfunction has yet been identified. In this study we investigated the neuroprotective effects of the triple herbal extract DA-9805 in experimental models of PD. DA-9805 was prepared by extracting three dried plant materials (Moutan cortex, Angelica Dahurica root, and Bupleurum root in a 1:1:1 mixture) with 90% ethanol on a stirring plate for 24 h at room temperature and fingerprinted using high-performance liquid chromatography. 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and its active metabolite 1-methyl-4-phenylpyridinium (MPP+), which both exert neurotoxic effects on dopaminergic neurons by inhibiting mitochondrial oxidative phosphorylation (OXPHOS) complex I, were used to make experimental models of PD. In MPP+-treated SH-SY5Y cells, DA-9805 ameliorated the suppression of tyrosine hydroxylase expression and mitochondrial damage on OXPHOS complex 1 activity, mitochondrial membrane potential, reactive oxygen species (ROS) generation, and oxygen consumption rate. In the MPTP-induced subacute PD model mice, oral administration of DA-9805 recovered dopamine content as well as bradykinesia, as determined by the rotarod test. DA-9805 protected against neuronal damage in the substantia nigra pars compacta (SNpc) and striatum. In both in vitro and in vivo models of PD, DA-9805 normalized the phosphorylation of AKT at S473 and T308 on the insulin signaling pathway and the expression of mitochondria-related genes. These results demonstrate that the triple herbal extract DA-9805 showed neuroprotective effects via alleviating mitochondria damage in experimental models of PD. We propose that DA-9805 may be a suitable candidate for disease-modifying therapeutics for PD.

Pharmacokinetics and Brain Distribution of the Active Components of DA-9805, Saikosaponin A, Paeonol, and Imperatorin in Rats.

DA-9805 is a botanical anti-Parkinson's drug candidate formulated from ethanol extracts of the root of Bupleurum falcatum, the root cortex of Paeonia suffruticosa, and the root of Angelica dahurica. The pharmacokinetics (PKs) and brain distribution of active/representative ingredients of DA-9805, Saikosaponin a (SSa; 1.1⁻4.6 mg/kg), Paeonol (PA; 14.8⁻59.2 mg/kg), and Imperatorin (IMP; 1.4⁻11.5 mg/kg) were evaluated following the intravenous or oral administration of each pure component and the equivalent dose of DA-9805 in rats. All three components had greater dose-normalized areas under the plasma concentration-time curve (AUC) and slower clearance with higher doses, following intravenous administration. By contrast, dose-proportional AUC values of SSa, PA, and IMP were observed following the oral administration of each pure component (with the exception of IMP at the highest dose) or DA-9805. Compared to oral administration of each pure compound, DA-9805 administration showed an increase in the AUC of SSa (by 96.1⁻163%) and PA (by 155⁻164%), possibly due to inhibition of their metabolism by IMP or other component(s) in DA-9805. A delay in the absorption of PA and IMP was observed when they were administered as DA-9805. All three components of DA-9805 showed greater binding values in brain homogenates than in plasma, possibly explaining why the brain-to-plasma ratios were greater than unity following multiple oral administrations of DA-9805. By contrast, their levels in cerebrospinal fluid were negligible. Our results further our understanding of the comprehensive PK characteristics of SSa, PA, and IMP in rats and the comparative PKs between each pure component and DA-9805.

Muscle echogenicity ratio can indicate severity of carpal tunnel syndrome.

INTRODUCTION: The purpose of this study was to investigate the usefulness of the echogenicity (EI) ratio of the thenar to hypothenar muscle measured using ultrasonography in assessing the severity of carpal tunnel syndrome (CTS). METHODS: Fifty-nine hands of 30 patients electrodiagnostically confirmed as having CTS were classified into 3 subgroups (mild, moderate, and severe). The EI of the thenar and hypothenar muscles was measured with ultrasonography, and the EI ratio was calculated in the patients and 13 normal participants (26 hands). RESULTS: The average EI ratio was higher in the CTS group than in the control group. We also found a positive correlation between the severity of CTS and a high EI ratio measured with ultrasonography. DISCUSSION: The EI ratio of the thenar to hypothenar muscle is a useful parameter that can indicate the severity of CTS. Muscle Nerve 58: 304-306, 2018.

Simultaneous determination of saikosaponin a, paeonol, and imperatorin, components of DA-9805, in rat plasma by LC-MS/MS and application to a pharmacokinetic study.

DA-9805 is a new botanical antiparkinson drug candidate formulated using an ethanolic extract of the root of Bupleurum falcatum, the root cortex of Paeonia suffruticosa, and the root of Angelica dahurica. In this study, a sensitive and rapid LC-MS/MS method was developed to simultaneously determine, saikosaponin a, paeonol, and imperatorin, three active/representative ingredients of DA-9805, in rat plasma. Plasma was extracted by mixture of ethyl acetate and methyl tertiary butyl ether. Chromatographic separation was carried out using a C18 column and a gradient elution of mobile phases consisting of 5mM formic acid in water and acetonitrile. Total chromatographic run time was 10.5min. Multiple reaction monitoring mode was used for mass spectrometry; the transitions were m/z 779.5→617.2 for saikosaponin a in negative-ion mode, m/z 167→149 for paeonol and m/z 271.1→203 for imperatorin in positive-ion mode. Calibration curves were constructed in the range of 0.5-1000ng/mL for saikosaponin a, 20-10000ng/mL for paeonol, and 0.2-1000ng/mL for imperatorin. All the validation data, including the selectivity, linearity, precision, accuracy, recovery, matrix effect, and stability satisfied the acceptance requirements. The method was successfully applied in a pharmacokinetic study of saikosaponin a, paeonol, and imperatorin following oral administration of DA-9805.

Alterations of papilla dimensions after orthodontic closure of the maxillary midline diastema: a retrospective longitudinal study.

PURPOSE: The aim of this study was to evaluate alterations of papilla dimensions after orthodontic closure of the diastema between maxillary central incisors. METHODS: Sixty patients who had a visible diastema between maxillary central incisors that had been closed by orthodontic approximation were selected for this study. Various papilla dimensions were assessed on clinical photographs and study models before the orthodontic treatment and at the follow-up examination after closure of the diastema. Influences of the variables assessed before orthodontic treatment on the alterations of papilla height (PH) and papilla base thickness (PBT) were evaluated by univariate regression analysis. To analyze potential influences of the 3-dimensional papilla dimensions before orthodontic treatment on the alterations of PH and PBT, a multiple regression model was formulated including the 3-dimensional papilla dimensions as predictor variables. RESULTS: On average, PH decreased by 0.80 mm and PBT increased after orthodontic closure of the diastema (P<0.01). Univariate regression analysis revealed that the PH (P=0.002) and PBT (P=0.047) before orthodontic treatment influenced the alteration of PH. With respect to the alteration of PBT, the diastema width (P=0.045) and PBT (P=0.000) were found to be influential factors. PBT before the orthodontic treatment significantly influenced the alteration of PBT in the multiple regression model. CONCLUSIONS: PH decreased but PBT increased after orthodontic closure of the diastema. The papilla dimensions before orthodontic treatment influenced the alterations of PH and PBT after closure of the diastema. The PBT increased more when the diastema width before the orthodontic treatment was larger.

Food Impaction and Periodontal/Peri-Implant Tissue Conditions in Relation to the Embrasure Dimensions Between Implant-Supported Fixed Dental Prostheses and Adjacent Teeth: A Cross-Sectional Study.

BACKGROUND: Food impaction and periodontal/peri-implant tissue conditions were evaluated in relation to the embrasure dimensions between implant-supported fixed dental prostheses (FDPs) and adjacent teeth. METHODS: A total of 215 embrasures of 150 FDPs in 100 patients (55 males and 45 females, aged 27 to 83 years; mean age: 56 years) were included in the study. Clinical assessments of the periodontal/peri-implant mucosal conditions, radiographic assessments of embrasure dimensions, and overall patient satisfaction were used as explanatory variables for the food impaction and periodontal/peri-implant tissue conditions adjacent to implant-supported FDPs in the generalized estimating equation (GEE) analysis. RESULTS: Food impaction was reported in 96 (44.7%) of 215 embrasures between implant-supported FDPs and adjacent teeth. Food impaction was reported more frequently in the embrasures with proximal contact loss than in those with tight contact (P = 0.009). Overall patient satisfaction was influenced negatively by food impaction in the proximal embrasures (P = 0.01). Among embrasure dimensions, only the embrasure surface area (ESA) significantly influenced food impaction (P = 0.03). Significant influences of various embrasure dimensions on the periodontal/peri-implant mucosal conditions and bone level at the implant were found in the univariate and multivariate GEE analyses. CONCLUSIONS: Food impaction between implant-supported FDPs and adjacent teeth occurred more frequently when proximal contact was lost and ESA increased. Food impaction negatively affected overall patient satisfaction. Embrasure dimensions influenced the periodontal/peri-implant mucosal conditions and bone level at the implant.

Pharmacokinetics and brain distribution of tetrahydropalmatine and tetrahydroberberine after oral administration of DA-9701, a new botanical gastroprokinetic agent, in rats.

DA-9701, a new botanical gastroprokinetic agent, has potential for the management of delayed gastric emptying in Parkinson's disease if it has no central anti-dopaminergic activity. Therefore, we examined the pharmacokinetics of DA-9701 components having dopamine D2 receptor antagonizing activity, tetrahydropalmatine (THP) and tetrahydroberberine (THB), following various oral doses (80-328 mg/kg) of DA-9701. The distribution of THP and THB to the brain and/or other tissues was also evaluated after single or multiple oral administrations of DA-9701. Oral administration of DA-9701 yielded dose-proportional area under the plasma concentration-time curve (AUC0-8 h) and maximum plasma concentration (Cmax) values for THP and THB, indicating linear pharmacokinetics (except for THB at the lowest dose). THP and THB's large tissue-to-plasma concentration ratios indicated considerable tissue distribution. High concentrations of THP and THB in the stomach and small intestine suggest an explanation for DA-9701's potent gastroprokinetic activity. The maximum concentrations of THP and THB in brain following multiple oral DA-9701 for 7 d (150 mg/kg/d) was observed at 30 min after the last oral DA-9701 treatment: 131±67.7 ng/g for THP and 6.97±4.03 ng/g for THB. Although both THP and THB pass through the blood-brain barrier, as indicated by brain-to-plasma concentration ratios greater than unity (approximately 2-4), oral administration of DA-9701 at the effective dose in humans is not expected to lead to sufficient brain concentrations to exert central dopamine D2 receptor antagonism.

Gender differences in corydaline pharmacokinetics in rats.

1. Corydaline, an isoquinoline alkaloid, is one of the major active constituents in a new prokinetic botanical agent, DA-9701. It has been recommended that preclinical pharmacokinetic studies of natural medicines include both genders. Therefore, in this study, the pharmacokinetics of corydaline in male and female rats was evaluated following intravenous and oral administration of pure corydaline or DA-9701. 2. After intravenous administration of corydaline, the area under the plasma concentration-time curve (AUC) was significantly greater (by 46.4%) in female rats compared to male rats due to a 29.3% reduction in non-renal clearance in female rats. The gender difference in corydaline hepatic metabolic clearance was supported by a significantly slower metabolism of corydaline in hepatic microsomes of female rats mediated via male-specific (CYP2C11 and CYP3A2) or male-dominant (CYP3A1) CYP isozymes. 3. Following oral administration of pure corydaline or DA-9701, the AUC and Cmax values of corydaline in female rats were significantly greater (by 793% and 466% increase for corydaline administration or by 501% and 143% increase for DA-9701 administration) than in male rats. Greater F values of corydaline in female rats could be due to smaller hepatic first-pass extraction as a result of slower hepatic metabolism of corydaline. 4. However, we observed a comparable disappearance of corydaline in male and female human liver microsomes, consistent with little gender difference in CYP2C9 and CYP3A activities in humans compared to that in rats. Thus, gender differences in corydaline metabolism are not expected to occur in humans.

Pharmacokinetics of chlorogenic acid and corydaline in DA-9701, a new botanical gastroprokinetic agent, in rats.

1.Few studies describing the pharmacokinetic properties of chlorogenic acid (CA) and corydaline (CRD) which are marker compounds of a new prokinetic botanical agent, DA-9701, have been reported. The aim of the present study is to evaluate the pharmacokinetic properties CA and CRD following intravenous and oral administration of pure CA (1-8 mg/kg) or CRD (1.1-4.5 mg/kg) and their equivalent dose of DA-9701 to rats. 2. Dose-proportional AUC and dose-independent clearance (10.3-12.1 ml/min/kg) of CA were observed following its administration. Oral administration of CA as DA-9701 did not influence the oral pharmacokinetic parameters of CA. Incomplete absorption of CA, its decomposition in the gastrointestinal tract, and/or pre-systemic metabolism resulted in extremely low oral bioavailability (F) of CA (0.478-0.899%). 3. CRD showed greater dose-normalized AUC in the higher dose group than that in lower dose group(s) after its administration due to saturation of its metabolism via decreased non-renal clearance (by 51.3%) and first-pass extraction. As a result, the F of CRD following 4.5 mg/kg oral CRD (21.1%) was considerably greater than those of the lower dose groups (9.10 and 13.8%). However, oral administration of CRD as DA-9701 showed linear pharmacokinetics as a result of increased AUC and F in lower-dose groups (by 182% and 78.5%, respectively) compared to those of pure CRD. The greater oral AUC of CRD for DA-9701 than for pure CRD could be due to decreased hepatic and/or GI first-pass extraction of CRD by other components in DA-9701.

Relationship among serum taurine, serum adipokines, and body composition during 8-week human body weight control program.

Human adipose tissue is not only a storage organ but also an active endocrine organ to release adipokines. This study was conducted to investigate the relationship among serum taurine and adipokine levels, and body composition during 8-week human body weight control program in obese female college students. The program consisted of diet therapy, exercise, and behavior modification. After the program, body weight, body fat mass, percent body fat, and body mass index (BMI) were significantly decreased. Serum triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) levels were significantly decreased. Also serum adiponectin level was significantly increased and serum leptin level was significantly decreased. There were no differences in serum taurine and homocysteine levels. The change of serum adiponectin level was positively correlated with change of body fat mass and percent body fat. These results may suggest that body fat loss by human body weight control program is associated with an increase in serum adiponectin in obese female college students. Therefore, further study such as taurine intervention study is needed to know more exact correlation between dietary taurine intake and serum adipokines or body composition.

Carpal tunnel syndrome: Clinical, electrophysiological, and ultrasonographic ratio after surgery.

INTRODUCTION: The aim of this study was to improve our understanding of the pathophysiology of carpal tunnel syndrome (CTS) and to highlight the ultrasonographic cross-sectional area (CSA) ratio as a tool for assessing outcomes by investigating postoperative changes. METHODS: Twenty-four individuals with CTS were evaluated using the Boston questionnaire, nerve conduction studies, and ultrasound, preoperatively and at 3 weeks and 3 months postoperatively. RESULTS: Improved symptom scores, decreased CSA, and decreased CSA ratio were observed in the first 3 weeks, but functional improvement was also observed after 3 weeks postoperatively. The ratios between the CSA at the sites of enlargement and unaffected areas correlated significantly with the Padua classification, although the coefficient was not superior to the coefficient of CSA at the maximal swelling site. CONCLUSIONS: Symptoms improved more rapidly than function after surgery. Measurement of the ultrasonographic CSA ratio may provide clinicians with a useful assessment tool after surgery.

Avoiding false-negative nerve conduction study in ulnar neuropathy at the elbow.

INTRODUCTION: Ulnar nerve displacement at the elbow causes overestimation of nerve conduction velocity. We hypothesized that this overestimation may cause false-negative results when the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) diagnostic criteria are used. METHODS: We investigated 9 cases of ulnar neuropathy at the elbow, all having ulnar nerve displacement confirmed by ultrasonography and meeting none or just one of the AANEM criteria with distance measurement by anatomic landmarks. First, the distance across the elbow segment was measured by anatomic landmarks, and then it was re-estimated by ultrasonography. RESULTS: Overestimated ulnar conduction velocity was corrected by 7.9 m/s. Three cases met none of the AANEM criteria before correction. After correction of overestimation, all cases met two of the AANEM criteria. CONCLUSION: This study highlights the importance of using ultrasonography to confirm the possibility of ulnar nerve displacement, especially when electrodiagnostic findings do not meet AANEM criteria in patients with suspected UNE.

Usefulness of ultrasonography to predict response to injection therapy in carpal tunnel syndrome.

OBJECTIVE: To verify the feasibility of initial parameters of ultrasonography or electromyography for the prediction of effect after steroid injection therapy in a carpal tunnel syndrome (CTS) patient. METHOD: We recruited individuals with clinical and electrodiagnostic evidence of CTS. Results from the Boston self-assessment questionnaire, median motor and sensory nerve conduction studies, and median nerve ultrasonography were evaluated at baseline, 1 month, and 6 months after injection. Evaluation of median nerve ultrasonography parameters included measurements taken at the maximal swelling point (MS), 2 cm proximal from MS (2MS), and 12 cm proximal from MS (12MS), and its ratio (MS/12MS, 2MS/12MS) was calculated. The correlation between improvement of the symptom score after treatment and baseline parameters was estimated. RESULTS: Fourteen individuals (14 women, mean age 53.8 years) with 22 affected wrists were enrolled. After steroid injection therapy, clinical and electromyographic parameters showed significant improvements at 1 month or 6 months after injection, and ultrasonographic parameters showed significant changes in maximal area and area ratio (MS/12MS) of the median nerve. Symptom score improvement showed a positive correlation in the initial 2MS and ratio of 2MS/12MS after 6 months (p<0.05). CONCLUSION: Most of the improvements occurred during the first month after injection and lasted up to 6 months. The initial median nerve swelling and its ratio may be a useful predictor of response after steroid injection.

Effect of taurine chloramine on the production of matrix metalloproteinases (MMPs) in adiponectin- or IL-1beta-stimulated fibroblast-like synoviocytes.

BACKGROUND: Adiponectin greatly stimulated the expression of matrix metalloproteinases (MMPs) in fibroblast-like synoviocytes (FLSs) as did IL-1beta. We wondered whether taurine chloramine (TauCl) inhibits the production of MMPs stimulated by adiponectin in the same pattern as by IL-1beta stimulation in vitro METHODS: Synovial cells from rheumatoid arthritis (RA) patients were treated with adiponectin or interleukin (IL)-1beta for 24 hr in the presence or absence of TauCl. The culture supernatant was collected and the levels of MMPs were measured by enzyme-linked immunosorbent assay (ELISA). The IkappaB signaling pathways stimulated by adiponectin were studied and the levels of NF-kappaB in the nuclei of the cells were analyzed by ELISA. RESULTS: TauCl (600 microM) inhibited MMP-13, but not MMP-1, expression in IL-1beta-stimulated RA FLSs. However, TauCl at the same concentration significantly inhibited the production of both adiponectin-stimulated MMP-1 and MMP-13 expression. TauCl inhibited the degradation of IkappaB-alpha stimulated by adiponectin, but not by IL-1beta. Similarly, the level of NF-kappaB in the nucleus was increased by adiponectin stimulation and was inhibited by 600 microM TauCl. However, the levels of NF-kappaB increased by IL-1beta stimulation were not inhibited by 600 microM TauCl. CONCLUSIONS: TauCl more effectively inhibited MMPs expression induced by adiponectin than that by IL-1beta in RA FLS, suggesting that TauCl plays an important role in down-regulating the expression of MMPs in arthritic joints.

Relationship of occlusion and gingival recession / 대한치주과학회지

Many factors have been implicated in the etiology of gingival recession, including faulty toothbrushing, the position of the tooth in the arch(malalignment), the presence of inflammation, frenal attachment, impingement of restoration margins, orthodontic treatment and trauma from occlusion. Among the many factors, this study was to evaluate the relationship of occlusion and gingival recession. 640 teeth without other etiologic factors of gingival recession were evaluated in 40 subjects aged 21-59 years. Only 1st, 2nd premolar and molar were included in this study. We recorded nonworking contacts, working contacts, cervical abrasion, sex, gingival recession and evaluated that relation of occlusion and gingival recession. The results of this study were as follows; 1. Teeth with nonworking contacts were significantly more gingival recession than teeth without nonworking contacts.(p0.01)

Study on tooth mortality after periodontal therapy / 대한치주과학회지

The main goal of periodontal treatment is the long-term maintenance of teeth. Periodic maintenance program is need to prevent periodontal disease and maintain healthy periodontium. Hirschfeld and Wasserman(1978) studied 600 treated periodontal patients. This study categorized periodontal patients using well-maintained, downhill, extreme downhill groups. The purpose of our study is to evaluate effect of periodontal treatment and analyse tooth loss after periodontal treatment using this classification. The study population of 59 patients had been treated and maintained for mean 5.8 years. All patients were on a periodic maintenance program at 2-, 3-, 4-, or 6-month intervals. The average age of the patients at the time of original therapy was 49.6 years. To analyse tooth loss, modified classification was used on the basis of response to therapy using by Hirschfeld and Wasserman in 1978. The results were as follows: 1. 59 treated patients were lost mean 1.42 teeth per patient for 5.8 years of maintenance period. 2. Maxillary first molars were most frequently lost but mandibular lateral incisors were lost no tooth during maintenance period. 3. Tooth mortality received surgical treatment had similar to received nonsurgical treatment. 4. Tooth loss was more frequent in maxillary teeth than mandibular teeth, and posterior teeth than anterior teeth, and more frequent tendency in male than female.