Effect of Fetal Sex Hormone on the Development of Alzheimer’s Disease in Woman:A Cross-Sectional Study Using 2D/4D Digit Length Ratio

Objective@#The purpose of this study is to investigate an association between sex-hormone exposure during fetal period and the development of Alzheimer’s disease (AD). @*Methods@#Twenty four AD patients and 25 normal controls were included from Memory Impairment Clinic of Pusan National University Hospital in Korea. Subjects are measured the ratio of the length of the second to the fourth digit (2D/4D) to estimate fetal sex-hormone exposure. Analysis of covariance was used to investigate an association between fetal sex-hormone exposure and the development of AD after adjusting age, education level, Korean Mini-Mental Status Examination and head circumference. @*Results@#We found that the females with AD had significantly lower 2D/4D ratios than the female controls. In the females withAD, the 2D/4D ratios in the left hand was 0.021 and 0.017 in the right hand compared with the controls. @*Conclusion@#Our findings suggest that the development of AD in female may be related with higher testosterone and lower es-trogen exposure during fetal period.

Effect of Amyloid Deposition in PET on Hippocampal Metabolism in Amnestic-Mild Cognitive Impairment : Pilot Study / 생물치료정신의학

OBJECTIVES: Most studies of hippocampal metabolism(HM) in amnestic mild cognitive impairment(aMCI) gave inconsistent results. Our objective was to evaluate the effect of amyloid-beta(Aβ) status on hippocampal metabolism in aMCI.METHODS: Overall, 23 aMCI underwent three-dimensional magnetic resonance imaging(MRI), ¹⁸F-fluorodeoxyglucose-positron emission tomography(¹⁸FDG-PET) and ¹⁸F-Fluorbetaben amyloid positron emission tomography (amyloid-PET). According to Aβ status on amyloid PET, 23 aMCI were classified as either Aβ+aMCI(N=13) or Aβ−aMCI(N=10). The primary outcome was HM using ¹⁸FDG-PET and we investigate the difference on HM between Aβ+aMCI and Aβ−aMCI using analysis of variance(ANOVA) model, after controlling hippocampal volume.RESULTS: We found that HM was more decreased in Aβ+aMCI than Aβ−aMCI. This result was not changed after controlling hippocampal volume.CONCLUSION: Our findings suggest that Aβ+ is associated with decreased HM, regardless of hippocampal volume, in aMCI.

Hippocampal Atrophy and Psychotic Symptoms in Patients with Alzheimer's Disease / 신경정신의학

OBJECTIVES: This study examined the difference in the volume or thickness of the medial temporal lobe between Alzheimer's disease patients with psychosis (AD+P) and those without psychosis (AD−P). METHODS: Overall, 31 AD+P patients and 29 AD−P patients were included from the Memory impairment clinics of Pusan National University Hospital in Korea. AD+P was diagnosed according to Jeste and Finkel's proposed diagnostic criteria for psychosis of Alzheimer's disease. AD−P included AD patients with no psychotic symptoms during a 5-year follow-up period. Medial temporal volume or thickness was measured by 3-tesla MRI and freesufer analysis. Analysis of variance was used to examine the difference in the volume or thickness of medial temporal lobe between AP+P and AD−P after controlling for age, gender, education years, Clinical Dementia Rating scale-Sum of Box, and total intracranial volume. RESULTS: The hippocampal volume in AD+P was smaller than that in AD−P. CONCLUSION: These findings suggest that AD+P is associated with a reduced hippocampal volume.

Association of Temporal Lobe Atrophy and Psychosis in Patients with Alzheimer's Disease

OBJECTIVE: The purpose of this study is to investigate the difference on regional volume in temporal lobe between Alzheimer's disease patients with psychosis (AD+P) and Alzheimer's disease patients without psychosis (AD-P). METHODS: Altogether, 24 AD+P and 25 AD-P matched age, gender, and clinical dementia rating sum of box (CDR-SOB) were include from a Memory impairment clinics of Pusan National University Hospital in Korea. AD+P were diagnosed according to Jeste and Finkel's proposed diagnostic criteria for psychosis of Alzheimer's disease. Grey matter volume of temporal lobe was measured with 3-tesla magnetic resonance imaging and freesufer analysis. Analysis of variance was used to investigate the association between temporal lobe and AD+P after controlling age, gender, education years, CDR-SOB and total intracranial volume. RESULTS: We found an association between AD+P and reduced grey matter volume in total temporal lobe as well as in specific temporal regions such as left middle temporal lobe, left inferior temporal lobe, both hippocampus and both fusiform. CONCLUSION: Our findings suggest that AD+P are associated with reduced grey matter volume of temporal lobe.

Neurobiological Mechanism of Memory

Memory is one of the most important mental mechanisms which is crucial for us to adapt to environmental surroundings and to maintain our identity. The neurobiological mechanisms for memory are based upon the synaptic plasticity that involve both functional and structural changes at the synapses in the neural circuits participating in learning and memory. Memory is not a single process but has two forms of short-term and long-term memory that are two independent but overlapping processes that blend into one another. The short-term memory depends upon the functional change of synaptic strength but the long-term memory requires anatomic changes of synapses in the neural circuit. Memory storage seems to use elements of a common genetic switch, involving cyclic adenosine monophospate (cAMP)-dependent protein kinase, mitogen activated protein kinase, and cAMP response element-binding protein, to convert short-term memory into long-term memory.

Reduced Cortical Thickness in Patients with Late Life Depression without Cerebral Vascular Disease

OBJECTIVES: The aim of this study is to compare cortical thickness in late life major depression patients without cerebral vascular disease (CVD) with that of non-depressed normal comparison subjects using magnetic resonance imaging (MRI). METHODS: Altogether, 47 subjects were finally recruited from the Memory impairment clinics of Pusan National University Hospital in Korea. All subjects (late life major depression patients without CVD : n=21, matched non-depressed normal comparison subjects : n=26) underwent 3-tesla MRI. RESULTS: Late life major depression patients without CVD showed reduced cortical thickness in left precuneus, left inferior temporal gyrus, and left cuneus compared with non-depressed normal comparison subjects. CONCLUSION: Our findings suggest that late life major depression without CVD is associated with reduced cortical thickness.

Erratum: Neuroanatomical Correlation of Agitation/Aggression in Alzheimer's Disease

We found an error in our published article.

A Pilot Study for Discovering Candidate Genes of Chromosome 18q21 in Methamphetamine Abusers: Case-control Association Study

OBJECTIVE: It was previously suggested that the malic enzyme 2 (ME2) as the candidate gene for psychosis in fine mapping of chromosome 18q21. Chromosome 18q21 is also one of the possible regions that can contribute to addiction. METHODS: We performed a pilot study for discovering candidate gene of chromosome 18q21 in the methamphetamine abusers for elucidating the candidate gene for methamphetamine addiction leading to psychosis. We have selected 30 unrelated controls (16 males, 14 females; age=59.8+/-10.4) and 37 male methamphetamine abusers (age=43.3+/-7.8). We analyzed 20 single nucleotide polymorphisms (SNPs) of 7 neuronal genes in chromosome 18q21 for DNA samples that was checked for the data quality and genotype error. The association between the case-control status and each individual SNP was measured using multiple logistic regression models (adjusting for age and sex as covariates). And we controlled false discovery rate (FDR) to deal with multiple testing problem. RESULTS: We found 3 significant SNPs of 2 genes in chromosome 18q21 (p-value<0.05; adjusting for age as covariate) in methamphetamine abusers compared to controls. We also found 2 significant SNPs of 1 gene (p-value<0.05; adjusting for age and sex as covariates) (rs3794899, rs3794901:MAPK4). Two SNPs in MAPK4 gene were significant in both statistical groups. CONCLUSION: MAPK4, the gene for mitogen-activated protein kinase 4, is one of the final 6 candidate genes including ME2 in 18q12-21 in our previous finemapping for psychosis. Our results suggest that MAPK4 can be a candidate gene that contribute to the methamphetamine addiction leading to psychosis.

Neuroanatomical Correlation of Agitation/Aggression in Alzheimer's Disease

OBJECTIVES: The aim of this study is to identify the association between agitation/aggression and atrophy in specific brain areas in Alzheimer's disease (AD). METHODS: Fifty six patients with mild or moderate AD participated in this study. Cognitive function was measured using the Korean version of the Mini-Mental State Examination (K-MMSE), and Clinical Dementia Rating (CDR). Agitation/aggression symptoms were measured using the Korean version of the Neuropsychiatric Inventory (K-NPI). Atrophies of brain were analyzed using Voxel Based Morphometry (VBM). RESULTS: Higher scores of agitation/aggression were correlated with the atrophy of left middle temporal, left fusiform, right middle temporal, left inferior temporal, right inferior temporal, left superior temporal, left middle occipital, right orbitofrontal, right superior frontal, left angular and right middle frontal gyrus (p<0.001, uncorrected for multiple comparisons, extent threshold=200 voxel). CONCLUSION: Agitation/aggression was correlated with specific neuroanatomical changes in mild or moderate AD.

Transpedicular Curettage and Drainage of Infective Lumbar Spondylodiscitis: Technique and Clinical Results

BACKGROUND: Infective spondylodiscitis usually occurs in patients of older age, immunocompromisation, co-morbidity, and individuals suffering from an overall poor general condition unable to undergo reconstructive anterior and posterior surgeries. Therefore, an alternative, less aggressive surgical method is needed for these select cases of infective spondylodiscitis. This retrospective clinical case series reports our novel surgical technique for the treatment of infective spondylodiscitis. METHODS: Between January 2005 and July 2011, among 48 patients who were diagnosed with pyogenic lumbar spondylodiscitis or tuberculosis lumbar spondylodiscitis, 10 patients (7 males and 3 females; 68 years and 48 to 78 years, respectively) underwent transpedicular curettage and drainage. The mean postoperative follow-up period was 29 months (range, 7 to 61 months). The pedicle screws were inserted to the adjacent healthy vertebrae in the usual manner. After insertion of pedicle screws, the drainage pedicle holes were made through pedicles of infected vertebra(e) in order to prevent possible seeding of infective emboli to the healthy vertebra, as the same instruments and utensils are used for both pedicle screws and the drainage holes. A minimum of 15,000 mL of sterilized normal saline was used for continuous irrigation through the pedicular pathways until the drained fluid looked clear. RESULTS: All patients' symptoms and inflammatory markers significantly improved clinically between postoperative 2 weeks and postoperative 3 months, and they were satisfied with their clinical results. Radiologically, all patients reached the spontaneous fusion between infected vertebrae and 3 patients had the screw pulled-out but they were clinically tolerable. CONCLUSIONS: We suggest that our method of transpedicular curettage and drainage is a useful technique in regards to the treatment of infectious spondylodiscitic patients, who could not tolerate conventional combined anterior and posterior surgery due to multiple co-morbidities, multiple level infectious lesions and poor general condition.

A Case of Right Cerebellopontine-Angle Lesion: Psychotic Symptoms and Magnetic Resonance Imaging Findings

Here, we report psychotic symptoms together with a right cerebellopontine-angle lesion. A37-year-old female patient presented with a trigeminal Schwannoma occupying the right cerebellopontine angle. Her psychotic symptoms included auditory hallucinations and delusions of persecution. T1- and T2-weighted images on magnetic resonance imaging (MRI) revealed hyperintense and hypointense areas in the right cerebellopontine angle, respectively. The clinical and neuroimaging reviews in this case suggest that sudden onset of psychotic symptoms at a mature age may be associated with a right cerebellopontine-angle lesion and that MRI should be used to evaluate possible organic bases in patients that present with psychosis.

Association of the Neuronal Cell Adhesion Molecule (NrCAM) Gene Variants with Personality Traits and Addictive Symptoms in Methamphetamine Use Disorder

OBJECTIVE: 1) To investigate the relationship between NrCAM polymorphisms and methamphetamine abuse in an ethnically homogenous Korean population. 2) To further support our findings by investigating the association among NrCAM gene variants, certain personality traits, and addictive symptoms of methamphetamine abusers. METHODS: Thirty-seven male methamphetamine abusers (age=43.3+/-7.8) and30 non-users (16 men, 14 women; age=59.8+/-10.4) were recruited. Ten single nucleotide polymorphisms (SNPs) in the NrCAM gene were assayed to compare genotype distributions between the 2 groups. Personality characteristics were measured using the Temperament and Character Inventory (TCI) and the NEO Personality Inventory, Revised (NEO PI-R). Addictive symptoms were assessed using the Diagnostic Interview for Genetic Studies (DIGS) and reviews of the subject's medical records. RESULTS: Among the 10 SNPs in the NrCAM gene, the frequency of the TA genotype at rs1990162 was significantly lower in methamphetamine abusers compared to non-users (p=0.042). In the 3 NrCAM gene SNPs (rs381318, rs2072546, and rs6954366), the distribution of genotypes and alleles were significantly associated with some traits in the TCI and NEO PI-R. Genotypes and alleles at 5 gene SNPs (rs2142325, rs381318, rs1269621, rs1269634, and rs1990162) were associated with certain addictive symptom dimensions in the patients. CONCLUSION: These findings support the idea that NrCAM is associated with genetic susceptibility of methamphetamine abuse and is also associated with certain personality characteristics that may increase disturbed addictive behavior.

The Prevalence of Osteoporosis or Degenerative Osteoarthritis of Knee in Female Patients with Lumbar Spinal Stenosis Over 50 Years

OBJECTIVE: To evaluate the prevalence of osteoporosis and degenerative knee osteoarthritis (OA) in female patients over 50 years, who were surgically indicated for lumbar spinal stenosis (LSS). METHODS: The study subjects were 76 female patients who underwent spinal surgery for LSS between January and December 2006. Radiographs of thoracolumbar spine, hip and knee were taken. Osteoporotic profiles including lumbar and hip bone mineral density (BMD) measurements and proper treatment of osteoporosis were investigated. RESULTS: The mean age was 65.1 (50~86) years old. Seven-teen patients (22.4%) and nine-teen patients (25.0%) had spine and hip BMD below a T score of -2.5. Thirty-two patients (48.0%) and four patients (5.2%) had knee and hip OA of K-L grade III and IV each. Old thoracolumbar osteoporotic compression fractures were confirmed in 6 patients (7.8%). Forty-eight percent (48.0%) of enrolled patients had hypovitaminosis D. According to osteoporosis guidelines from the Korean Society of Bone Metabolism, 31 patients (40.7%) qualified to be candidates of intensive osteoporosis treatments. CONCLUSION: The prevalence of osteoporosis and knee OA in LSS patients was 25.0% and 42.1%. Based on checking up BMD and knee OA in female patient with LSS, proper treatments of osteoporosis and degenerative knee OA should be considered.

Depressive Symptom-Related Factors in Patients with Breast Cancer / 한국유방암학회지

PURPOSE: Patients with breast cancer are at risk for developing psychological distress and psychiatric disorders such as depression. The aim of this study was to assess the depressive symptom related factors in women with breast cancer. METHODS: A total of 211 patients with breast cancer who had undergone an operation within 5 years participated in this survey with consent. Depressive symptoms in patients were measured using the 21-item Beck Depression Inventory (BDI) questionnaire in the outpatient clinic and sociodemographic, clinicopathologic factors of the patients were analyzed with a BDI score. The patients were divided into group A (BDI or =16, n=65). RESULTS: The mean age of the patients was 49.2 years and the mean follow-up period was 22 months. In the univariate analyses, postmenopausal status (p=0.014), tumor size (p=0.023) and presence of progesterone receptor (p=0.012) were significantly associated with depressive symptom. In multivariate analysis, only postmenopause (p=0.021) and tumor size (p=0.018) were related with depressive symptom. CONCLUSION: Depressive symptom is common in patients with breast cancer and a screening test for depression is needed in breast cancer patient who experienced menopause or has bigger tumor size.

Pulsed Electromagnetic Field Stimulates Cellular Proliferation in Human Intervertebral Disc Cells

PURPOSE: The purpose of this study is to investigate the mechanism of cellular proliferation of electromagnetic field (EMF) on human intervertebral disc (IVD) cells. MATERIALS AND METHODS: Human IVD cells were cultured three-dimensionally in alginate beads. EMF was exposed to IVD cells with 650Omega, 1.8 millitesla magnetic flux density, 60 Hz sinusoidal wave. Cultures were divided into a control and EMF group. Cytotoxicity, DNA synthesis and proteoglycan synthesis were measured by MTT assay, [3H]-thymidine, and [35S]-sulfate incorporation. To detect phenotypical expression, reverse transcription-polymerase chain reactions (RT-PCR) were performed for aggrecan, collagen type I, and type II mRNA expression. To assess action mechanism of EMF, IVD cells were exposed to EMF with NG-Monomethyl-L-arginine (NMMA) and acetylsalicylic acid (ASA). RESULTS: There was no cytotoxicity in IVD cells with the EMF group in MTT assay. Cellular proliferation was observed in the EMF group (p < 0.05). There was no difference in newly synthesized proteoglycan normalized by DNA synthesis between the EMF group and the control. Cultures with EMF showed no significant change in the expression of aggrecan, type I, and type II collagen mRNA compared to the control group. Cultures with NMMA (blocker of nitric oxide) or ASA (blocker of prostaglandin E2) exposed to EMF demonstrated decreased DNA synthesis compared to control cultures without NMMA or ASA (p < 0.05). CONCLUSION: EMF stimulated DNA synthesis in human IVD cells while no significant effect on proteoglycan synthesis and chondrogenic phenotype expressions. DNA synthesis was partially mediated by nitric oxide and prostaglandin E2. EMF can be utilized to stimulate proliferation of IVD cells, which may provide efficient cell amplification in cell therapy to degenerative disc disease.

A retrospective statistical analysis of dental implants / 대한치과보철학회지

STATEMENT OF PROBLEM: The number of edentulous patients is increasing due to an aging society, which leads to increased demands and interests on implant restorations. Implant restorations are an effective treatment method for both complete and partially edentulous patients, and the success rate has been reported to be high. But because of the increased use of implants in various situations have resulted in frequent reports of failures on implant restorations. Various efforts to overcome these failures have been made. PURPOSE: The aim of this study was to investigate the statistic survival rate of dental implants on patients who were treated at Dankook University Dental Hospital during the past 10 years based on their charts. Materials and methods :The research was made for two different periods of time; The first investigation was for patients from August, 1998 to August, 2003 and the second was for patients from September, 2003 to April, 2007. Information on the number of implants placed, the location and distribution of implants, the duration between the first and second surgery, and the survival rate of implants were investigated from the patients' charts. RESULTS: 1. According to the first investigation, 1680 implants were placed on 612 patients and the second investigation showed 2438 implants placed on 933 patients. Thus a total of 4118 implants on 1545 patients. 2. Among the 1545 patients, 884 patients were male (57.2%) and 661 patients were female (42.8%). Out of 4118 implants, 1739 implants (42.2%) were placed on the maxilla, and 2379 implants (57.8%) on the mandible. Implants were placed most frequently in the posterior region of the mandible. A total of 2043 implants (53.2%) were placed in this region. 3. According to the first investigation, 57 out of 1680, implants failed, while from the second investigation, 17 out of 2438 implants were reported as failure. In total, 74 implants failed, which results in a 98.2% survival rate. 4. The average duration between the first and the second surgeries in maxillas decreased from 7.4 months to 6.8 months. The duration also decreased from 5.6 months to 5.0 months in mandibles. CONCLUSION: As shown in the results, the number of placed implants and the survival rate of implants were higher in the second investigation than that of the first investigation. And the time spent after the first surgery to the second surgery was less in the second investigation. Consequently, it can be presumed that the demand and consumption of dental implants as well as the survival rate will increase in the future.

Lamotrigine Augmentation in Patients with Treatment-Resistant Major Depressive Disorder: A Naturalistic Study / 대한정신약물학회지

OBJECTIVE: Lamotrigine's possible efficacy in the treatment of depressive disorders has been suggested. This naturalistic study investigated clinical response to lamotrigine augmentation in patients with treatment-resistant depression. Characteristics of the lamotrigine-responders were also explored. METHODS: Clinical data from 40 lamotrigine- treated patients with treatment-resistant unipolar depression were analyzed. The subjects were diagnosed with DSM-IV major depressive disorder and resistant to at least 2 antidepressants. Efficacy of lamotrigine treatment was measured by the changes in mean scores of the Clinical Global Impression Severity subscale (CGI-S), which were extracted from the prospective mood chart and structured interviews. Response was defined as a decrease of at least 2 or more from baseline on the CGI-S. Untoward effects associated with lamotrigine treatment were also assessed through medical records. RESULTS: Significant reduction in the CGI-S mean score was observed from baseline through 8 week lamotrigine augmentation in 40 patients with treatment-resistant unipolar depression (t=5.7, df=39, p<.01), and the magnitude of treatment effect was large (r(effect size)=0.68). Drop-outs were mainly attributable to lamotrigine-associated rash (N=5). Greater rate of improvement was associated with responder group (N=14) compared to non-responder group (N=17) from week 3 onward. CONCLUSION: The results of current study lend support to the potential benefit of lamotrigine augmentation in a subpopulation of patients with treatmentresistant unipolar depression. Continuation of lamotrigine add-on for more than 3 weeks may be needed to assess clinical outcome. Lamotrigine augmentation was generally well-tolerated. Large scale, double-blind studies are necessary to confirm its use as an augmentation agent.

Differences of Glucose and Lipid Metabolism among the Type of Antipsychotic Drugs in Schizophrenia Patients with Long-Term Use of Antipsychotic Drugs / 대한정신약물학회지

OBJECTIVE: The development of metabolic disorders including diabetes mellitus and hyperlipidemia has been reported among schizophrenia patients treated with atypical antipsychotic drugs. The role of antipsychotic drugs in the development of this condition has not been proven yet. This study was conducted to investigate whether antipsychotic drugs that often induce weight gain influence glucose and lipid metabolism including insulin resistance and serum leptin level. METHODS: The study population consisted of 63 patients (all meeting DSM-IV criteria for schizophrenia), who were divided into 3 treatment groups: haloperidol (N=21), risperidone (N=21), and olanzapine (N=21) monotherapy, and 31 healthy control subjects. Fasting blood samples for glucose, insulin, leptin and lipids were analysed. In addition, insulin resistance (IR) was calculated through the homeostatic model assessment (HOMA) and body mass index (BMI) was also calculated. RESULTS: In patients receiving olanzapine, significant increases in BMI (p<0.01) and lipid profiles including LDL-cholesterol (p<0.05), triglyceride (p<0.01) and leptin levels (p<0.001) were found in comparison with the normal control group. A significantly higher degree of IR, as measured with the HOMA index, was found in patients receiving olanzapine than in patients receiving haloperidol (p<0.01) and risperidone (p<0.05), and in the normal control group (p<0.01). After removal of the impacts of BMI on the degree of HOMA-IR and serum leptin levels, the degree of HOMA-IR (p<0.05) and serum leptin levels (p<0.001) was also higher in patients receiving olanzapine than in the normal control group. CONCLUSION: The results of this study suggest that olanzapine has more significant influence on metabolic complications than haloperidol and risperidone and the characteristics of antipsychotic drug per se may be involved in the development of metabolic complication as well as weight change.

Genetic and Neurobiological Etiologies of Alcohol Dependence / 신경정신의학

The etiologies of alcohol dependence may be divided into three factors:biological, psychological, and social factors. Among these, many of the current articles deal with the genetic factors, due to rapid developments in methodology and so on. Because of these reasons, it is thought that it would be worthful to review the articles related to the genetic etiologies and other neurobiological etiologies of alcohol dependence at this point. Because alcohol dependence is a complicated and heterogenous disease, it is not likely to be associated with a single gene polymorphism. And as it is still early times in identifying its genetic etiology, I think it is not easy to make conclusion in this field now. However, I believe that many recent studies using endophenotype and haplotype will give us more promising results. The fact that unlike other substances, alcohol dose not act on only one or two neurotransmitter receptors makes neurobiological research to be not easy one. It is interesting that some of the articles reported in this fields recently dose not confined to brain reward system but extended to CRF or molecular biology.

A STUDY ON THE HEAT GENERATION OF BONE DRILLING BURS ACCORDING TO IRRIGATION DURING IMPLANTATION OF DENTAL IMPLANT / 대한치과보철학회지

There are a lot of elements affecting the success of implant prosthesis. The quality of surgical procedure is considered as one of the key factors. To avoid the excess heat generation is an important element of successful osseointegration and it can be achieved by using a gentle surgical technique with a sharp instrument in bone drilling. This study was performed to measure and analyze comparatively the heat transmitted to surrounding bone at a distance of 0.5mm from the periphery of the drill hole in each drilling stage. The results were as follows. In standard system, the temperature of surrounding bone tissue ranged from 29.2degrees Cto 48.3degrees C with irrigation and from 34.6degrees C to 84.3degrees C without irrigation. And in wide system, the temperature of surrounding bone tissue ranged from 29.5degrees C to 52.5degrees C with irrigation and from 34.8degrees C to 87.8degrees C without irrigation. And the temperature ranges exceeded the threshold without irrigation, while showing less than the threshold by the cooling effect of irrigation. In comparing standard system with wide system, although there was no significant difference, 4.3mm pilot and 4.3mm twist drill of wide system showed high value and wide system showed slightly high elevation of temperature in all depth in fixture installation In the finite element analysis, the calculated value by the Fourier's cooling law were applied to the bone drilling surface. And through analysis using different irrigation temperatures at 28degrees C, 15degrees C and 5degrees C, and according to the time. The result was that the cooling water at least below 15degrees C was required to maintain the temperature of surrounding bone less than threshold in bone drilling, the cooling water below 5degrees C was required to gain more sufficient cooling effect, and cooling over 5 seconds was needed after bone drilling for sufficient effect.