Faculty Profiles - KUBOKI Takuo

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実際の患者の問題点に基づく少数歯欠損機能回復法に関するチュートリアル教育の試み

窪木拓男, 園山亘, 荒川光, 鈴木康司, 藤沢拓生, 小島俊司, 笠井昭夫, 上原淳二, 杉山英樹, 前川賢治, 矢谷博文

日本補綴歯科学会雑誌 46 ( 5 ) 812 - 812 2002.12

CTGF/Hcs24, a hypertrophic chondrocyte specific gene product, stimulates the proliferation and expression of the cartilage phenotype but not hypertrophy or calcification or articular cartilage in culture.

Nishida T, Kubota S, Nakanishi T, Kuboki T, Yosimichi G, Kondo S, Takigawa M

J Cell Physiol 192, 55 - 63 2002

Correlation of the near-infrared spectroscopy signals with signal intensity in T<inf>2</inf>-weighted magnetic resonance imaging of the human masseter muscle Reviewed

Takuo Kuboki, Koji Suzuki, Kenji Maekawa, Mami Inoue-Minakuchi, Claver O. Acero, Yoshinobu Yanagi, Toru Wakasa, Kanji Kishi, Hirofumi Yatani, Glenn T. Clark

Archives of Oral Biology 46 721 - 727 2001.7

The purpose of this study was to compare and contrast blood volume changes transcutaneously measured using near-infrared (NIR) spectroscopy against water signal intensity changes taken from a transverse T2-weighted MR image of the masseter muscle in healthy human subjects before, during and after contraction. Eight healthy non-smoking males with no history of chronic muscle pain or vascular headaches participated (mean age: 23.9 ± 0.6 years). The MRI data were gathered using a turbo spin echo sequence (TR: 2300 ms; TE: 90 ms; FOV: 188 × 300 mm; scanning time: 30 s; slice thickness: 10 mm) and the slice level was set at the mid-point between the origin and insertion of the masseter. Intramuscular haemoglobin (Hb) levels and water content of the right masseter muscle were continuously monitored for 2 min before, 30 s during and 15 min after a maximum voluntary clenching (MVC) task. Both the near-infrared and MRI data were baseline-corrected and normalized and mean levels were established and plotted. Plots of the data showed that both near-infrared-based total Hb and T2-weighted MRI-based signal-intensity levels clearly decreased during contraction and a clear post-contraction rebound response was evident after the contraction. The near-infrared data were found to be highly correlated with MRI-based signal-intensity data (Pearson's r = 0.909, P < 0.0001). In conclusion, these data provide powerful evidence that near-infrared data (total Hb), transcutaneously taken from the masseter muscle in humans, will reflect the intramuscular water signal intensity changes seen using a T2-weighted MRI imaging method. © 2001 Elsevier Science Ltd.

DOI： 10.1016/S0003-9969(01)00030-9

一般歯科医院の受診患者における顎関節症の症状と徴候の変動 Reviewed

西村真紀, 景山正登, Yoshizo Matsuka, 畑中乾志, 吉田栄介, 水口一, 窪木拓男, 矢谷博文

The Journal of the Japan Association of Cranio-Mandibular Orthopedics Vol.14 ( No.1 ) 23 - 31 2001

Biomechanical calculation of human TM joint loading with jaw opening Reviewed

T Kuboki, Y Takenami, K Maekawa, M Shinoda, A Yamashita, GT Clark

JOURNAL OF ORAL REHABILITATION 27 ( 11 ) 940 - 951 2000.11

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-BLACKWELL

A three-dimensional, static mathematical calculation of the stomatognathic system was done to predict total temporomandibular joint (TMJ) loading at different levels of jaw opening. The model assumed that muscle forces acting on the mandible could be simulated by a combination of contractile components (CCs) and elastic components (ECs) and that static equilibrium existed within the body of the mandible. The model also imposed the constraint that any generated joint reaction force would act on the centre of the condyle. The results of the model demonstrated that under all conditions of opening and for all values of the elastic modulus selected, the forces between the TMJ condyle and the articular eminence were compressive in nature. The compressive force magnitude increased from 2 .7 to 27 .6 N incrementally as the jaw opened from 10 to 40 mm. Overall data in this study indicated that the TMJ tissues undergo low levels of compression at open positions up to 40mm. Finally, the condition of trismus (increased jaw closing activation with opening) was simulated, the Joint reaction force at 20 mm opening increased from 7 .7 to 64 .9 N with only a 20% activation of the dosers.

超音波形成と音波形成の違いによるピンブリッジのピンホール形成精度について

吉本彰夫, 山下敦, 大西栄史, 窪木拓男, 矢谷博文

日本補綴歯科学会雑誌 44 ( 3 ) 457 - 457 2000.6

Four-Year Longitudinal Course of TMD Symptoms in an Adult Population and the Estimation of Risk Factors in Relation to Symptoms

Manabu Kamisaka, Hirofumi Yatani, Takuo Kuboki, Yoshizo Matsuka, Hajime Minakuchi

Journal of Orofacial Pain 14 ( 3 ) 224 - 232 2000

Language：English Publishing type：Research paper (scientific journal)

Aims: To investigate the natural course of symptoms of temporomandibular disorders (TMD) in a non-patient population and to estimate the strength of the relationship between several hypothesized risk factors and precipitation and perpetuation of the symptoms. Methods: A total of 672 randomly selected citizens of Okayama City was requested to answer the same self-administered questionnaire that they had answered 4 years earlier. The mailed questionnaire failed to reach 58 subjects at the second survey, and 367 of the remaining subjects (59.8%) responded. The fluctuation of TMD symptoms was assessed by comparison of 6 pairs of answers for questions regarding temporomandibular joint (TMJ) pain, limitation of mouth opening, TMJ noise, headache, neck pain, and shoulder stiffness. Six factors (age under 40, female, clenching habit, history of extrinsic trauma, sleep disturbance, and family history of TMD) were tested for their relative risk in precipitating and perpetuating each TMD symptom by the use of its confidence interval to define significance. Results: The incidence of TMD symptoms ranged from 6.1% (TMJ pain) to 12.9% (TMJ noise). More than half of the subjects who had reported TMJ and neck pain at the initial survey no longer reported these symptoms at the second survey, whereas TMJ noise and shoulder stiffness remained in more than 70% of the subjects. Individuals under 40 years old had a 3.3:1 increased risk of precipitating TMJ noise (P &lt
0.01), individuals with a history of extrinsic trauma had a 2.85:1 increased risk of precipitating limited mouth opening (P &lt
0.01), and females had a 2.81:1 increased risk of perpetuating TMJ pain (P &lt
0.01). Conclusion: The possible etiologic significance of these factors in TMD should be validated hv future research.

Haemodynamic responses in chronically painful, human trapezius muscle to cold pressor stimulation

Claver O. Acero Jr, Takuo Kuboki, Kenji Maekawa, Atsushi Yamashita, Glenn T. Clark

Archives of Oral Biology 44 ( 10 ) 805 - 812 1999.10

Language：English Publishing type：Research paper (scientific journal)

The aim was to compare haemodynamic responses in trapezius muscles to cold pressor stimulation in individuals with localized trapezius myalgia and asymptomatic controls. Nine males with chronic localized pain in the trapezius (mean age, 23.2 years) and nine male controls (mean age, 24.6 years) who had no medical history of migraine, hypertension or sustained pain in the trapezius region were investigated. Two experimental (cold pressor and mock) trials were performed in a randomly assigned sequence. In the cold pressor trial the participant's left foot and ankle were immersed in 4°C cold water for 2 min
the mock trial was done without that stimulus. Blood volume was continuously recorded 1 min before, 2 min during, and 5 min after cold pressor stimulation using near-infrared spectroscopy. Each participant's blood-volume data were baseline-corrected and submitted to statistical analysis. Results showed that the individuals with muscle pain exhibited a significantly lower mean blood volume than the controls during cold pressor stimulation (p = 0.0367). Upon withdrawal of that stimulation, the mean blood volume in both groups fell below the baseline. These results suggest that individuals with chronic regional trapezius myalgia have less capacity to vasodilate this muscle during cold pressor stimulation than those without such myalgia. It is not yet known if this difference in the haemodynamic response is a cause or an effect of the myalgia.

DOI： 10.1016/S0003-9969(99)00082-5

Direct adenovirus-mediated gene delivery to the temporomandibular joint in guinea-pigs

Takuo Kuboki, Tohru Nakanishi, Manabu Kanyama, Wataru Sonoyama, Takuo Fujisawa, Kappei Kobayashi, Takumi Ikeda, Toshikazu Kubo, Atsushi Yamashita, Masaharu Takigawa

Archives of Oral Biology 44 ( 9 ) 701 - 709 1999.9

Language：English Publishing type：Research paper (scientific journal)

Adenovirus vector system is expected to be useful for direct gene therapy for joint disease. This study first sought to confirm that foreign genes can be transferred to articular chondrocytes in primary culture. Next, recombinant adenovirus vectors harbouring β-galactosidase gene (LacZ) was injected directly into the temporomandibular joints of Hartley guinea-pigs to clarify the in vivo transfer availability of the adenovirus vectors. Specifically, recombinant adenovirus harbouring LacZ gene (Ax1CALacZ) was injected into the upper joint cavities of both mandibular joints of four male 6-week-old Hartley guinea-pigs. Either the same amount of recombinant adenovirus without LacZ gene (Ax1w) suspension (placebo) or the same amount of phosphate-buffered saline solution (control) were injected into the upper joint cavities of both joints of another four male guinea-pigs. At 1, 2, 3 and 4 weeks after injection, the joints were dissected and the expression of delivered LacZ was examined by 5-bromo-4-chloro-3-indolyl-β-D- galactopyranoside (X-gal) staining and reverse transcriptase-polymerase chain reaction (RT-PCR). To investigate the expression of transferred gene in other organs, total RNA was extracted from liver, kidney, heart and brain and the expression of Latz mRNA and 18 S ribosomal RNA were analysed by RT-PCR. Clear expression of LacZ was observed in the articular surfaces of the temporal tubercle, articular disc and synovium of the temporomandibular joints even 4 weeks after injection in the Ax1CALacZ-injected group, while no expression was detected in placebo and control groups. Histological examination confirmed that LacZ activity was clearly detected in a few cell layers of the articular surface tissues, which is much more efficient than in a previously study of the knee joint. In the other organs, expression of the delivered transgene was not observed. Based on these findings, direct gene delivery into the articular surface of the temporomandibular joint using the adenovirus vector is feasible as an effective in vivo method.

DOI： 10.1016/S0003-9969(99)00069-2

Effect of intravenous infusion of a β-adrenergic blocking agent on the haemodynamic changes in human masseter muscle induced by cold-pressor stimulation

Kenji Maekawa, Takuo Kuboki, Takuya Miyawaki, Masahiko Shimada, Atsushi Yamashita, Glenn T. Clark

Archives of Oral Biology 44 ( 6 ) 475 - 483 1999.6

Language：English Publishing type：Research paper (scientific journal)

Eight healthy non-smoking males (mean age: 24.1 ± 1.1 years) without any history of chronic muscle pain and migraine participated in this study. Haemoglobin (Hb) and oxygen (O2) saturation in the right masseter muscle were continuously recorded with a non-invasive near-infrared spectroscopic device. Heart rate and blood pressure were also recorded. The experiment had three phases: a placebo drug (physiological saline) with cold-pressor trial, a 30-sec maximal voluntary clenching (MVC) trial, and a propranolol with cold-pressor trial. The saline and drug trials each involved continuous recording for 1 min before, 2 min during and 5 min after the cold-pressor stimulation (4°C). Physiological saline (20 ml) or propranolol hydrochloride (20 ml) were infused at the rate of 2 ml/min. This infusion was begun 20 min before the baseline recording and participants did not know which solution (saline or propranolol) was being infused. For the MVC trial, each participant was asked to perform a 30-sec clench of their jaw-closing muscles. There was a rest period of 15 min between each trial. The individual Hb and O2 data were normalized so that the baseline at the beginning of the experiment was equal to zero, and the Hb and O2 data were normalized as a percentage of the individual's own highest absolute Hb and O2 after and during the MVC, respectively. The results showed that the mean baseline Hb 1 min before cold-pressor stimulation was significantly lower in the β- blocker trial than in the placebo trial (p=0.035). The mean change in Hb from baseline during cold-pressor stimulation in the β-blocker trial was also significantly less than in the placebo trial (p = 0.035). The mean Hb rebound change after the cold-pressor stimulation in the β-blocker trial was significantly higher than in the placebo trial, and no significant heart- rate differences were observed in the period after cold-pressor stimulation. Overall, the mean heart rate before and during that stimulation was significantly lower in the β-blocker trial than the placebo trial (p &lt
0.001). There was no significant mean blood-pressure difference between placebo and β-blocker trials at any time. These results suggest that β- adrenoceptor blocking decreases the blood volume in the resting masseter, suppresses the incremental blood-volume change during cold-pressor stimulation, and discloses a hidden vasoconstrictive effect after that stimulation.

DOI： 10.1016/S0003-9969(99)00028-X

周期的な機械的ストレスを培養軟骨細胞に加え続けると,MMP及びIL-1の発現が誘導され,細胞外マトリックスの分解が引き起こされる

ピンブリッジ法の予後調査と新しい超音波形成器によるピンホール形成の試み

吉本彰夫, 山下敦, 窪木拓男, 白井知恵子, 今井誠

日本補綴歯科学会雑誌 43 ( 101回特別 ) 193 - 193 1999.5

Fujisawa Takuo, Hattori Takako, Takahashi Kojiro, Kuboki Takuo, Yamashita Atsushi, Takigawa Masaharu

The Journal of Biochemistry 125 ( 5 ) 966 - 975 1999.5

Language：English Publisher：(公社)日本生化学会

機械的刺激による軟骨の分解について調べた.Flexercell strain unitを用いて周期的張力(CTF)を培養軟骨細胞に加えたところ,5kPa及び15kPaの高頻度CTFにより,DNA合成,プロテオグリカン合成,コラーゲン合成の低下が見られた.15kPaの高頻度CTFではIL-1,matrix metalloproteinase-2(MMP-2),MMP-9のmRNAの発現と活性型MMP-9の産生が増加した.この時,プロテオグリカンの分解が促進したが,MMPの阻害剤の存在下では分解の促進が抑えられた.張力を小さくすると,軟骨の分解に関わる遺伝子の発現誘導は見られなかった.強度の高頻度CTFはIL-1,MMP-2,MMP-9のmRNAの発現,及び活性型MMP-9の産生を増大させることから,周期的な機械的ストレスが軟骨の分解を引き起こすと考えられる

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Specific antibodies against human cultured chondrosarcoma (HCS-2/8)and osteosarcoma(Saos-2)cells detected in the serum of the TMJ osteoarthritis patients.(共著)

Takuo Kuboki, Takako Hattori, Tsunehisa Mizushima, Manabu Kanyama, Takuo Fujisawa, Atsushi Yamashita, Masaharu Takigawa

Archs Oral Biol 44 ( 5 ) 403 - 414 1999.5

Publishing type：Research paper (scientific journal)

To find specific humoral antibodies in sera from patients with temporomandibular joint (TMJ) osteoarthritis (OA), an immortal human chondrocyte (HCS-2/8) and osteoblast (Saos-2) cell line derived from a chondrosarcoma and an osteosarcoma, respectively, were used as source proteins of human antigens. Patients with chronically painful TMJ OA (n = 18) but no other joints symptoms were selected from a consecutive series of patients with temperomandibular disorders and sex-matched asymptomatic controls (n = 8) were also recruited. Cellular proteins of the HCS-2/8 and Saos-2 cells were subjected to Western blotting with the OA and control sera as probes. Band-recognition frequency and the peak optical density of the band were compared between groups by χ2 and t-tests. OA sera recognized various bands for the chondrocytes, and one of these (47-kDa) was specific for the OA sera. In two OA patients whose treatment outcome was less favorable, the reactivity against the 47-kDa protein was relatively high. In addition, the OA sera clearly cross-reacted with recombinant HSP47. Based on these findings, an autoimmune reaction against chondrocytes could be one of the exaggerating and/or perpetuating mechanisms in the pathophysiology of osteoarthritic TMJs, and the humoral antibody titre against the HSP47-like protein derived from the chondrocytes could be one of the possible markers for the prognosis of the joint pathology.

DOI： 10.1016/S0003-9969(99)00009-6

Effect of intravenous infusion of an α-adrenergic blocking agent on the haemodynamic changes in human masseter muscle induced by cold pressor stimulation

Kenji Maekawa, Takuo Kuboki, Takuya Miyawaki, Masahiko Shimada, Atsushi Yamashita, Glenn T. Clark

Archives of Oral Biology 44 ( 4 ) 319 - 327 1999.4

Language：English Publishing type：Research paper (scientific journal)

This study evaluated the effect of intravenous infusion of a non- selective α-adrenergic blocking agent on masseter muscle haemodynamics induced by 4°C cold pressor stimulation (CPS) of the right foot and ankle, which reportedly evokes a rapidly increasing sympathetic nerve activity in human skeletal muscle. Nine healthy non-smoking males (mean age 23.7±2.1 year) with no history of chronic muscle pain or migraine participated. The haemoglobin (Hb) concentration in the right masseter was continuously recorded by non-invasive, near-infrared spectroscopy. Heart rate and blood pressure were also recorded. The experiment involved the following sequence: (1) a placebo (physiological saline) with a CPS trial
(2) a 30-sec maximal voluntary clenching (MVC)-only trial
and (3) an α-adrenergic blocking agent with a CPS trial. The saline and drug trials each involved continuous recording for 1 min before, 2 min during and 5 min after the CPS. Physiological saline (20 ml) or phentolamine mesylate (20 ml) were infused at the rate of 2 ml/min. This infusion was begun 15 min before baseline recording and participants were not aware which solution (saline or phentolamine) was being infused. For the MVC trial, each participant performed a 30-sec MVC of his jaw-closing muscles followed by a 15-min rest between, each trial. The individual Hb data were adjusted so that the baseline at the beginning of the experiment was equal to zero and all data were normalized as a percentage of the individual's highest absolute Hb change seen after the MVC. The mean baseline Hb concentrations 1 min before CPS were significantly higher in the α-blocker trial (83.6%) than in the placebo saline trial (P &lt
0.001). The change in mean Hb concentration from baseline during CPS in the α-blocker trial was significantly less than in the placebo trial (P = 0.006). Mean heart rate before CPS was also significantly higher in the α-blocker trial (85.2 beats/min) than in the placebo trial (69.6 beats/min) (P &lt
0.001). There were no significant differences in the mean systolic and diastolic blood pressures between the placebo and α-blocker trials in any time period. The results suggest that non-selective α-adrenoceptor blockade increases the blood volume in the masseter muscle. This change might be due to a combination of peripheral vasodilation and an increase in cardiac output.

DOI： 10.1016/S0003-9969(98)00127-7

Haemodynamic response to cold pressor stimulation on chronically painful trapezius muscle Reviewed

C.O.Acero, Jr, T.Kuboki, K.Maekawa, A.Yamashita, G.T.Clark

Arch Oral Biol 1999

Connective tissue growth factor induces the proliferation, migration, and tube formation of vascular endothelial cells in vitro, and angiogenesis in vivo

Tsuyoshi Shimo, Tohru Nakanishi, Takashi Nishida, Masahiro Asano, Manabu Kanyama, Takuo Kuboki, Takuya Tamatani, Katsunari Tezuka, Motohide Takemura, Tomohiro Matsumura, Masaharu Takigawa

Journal of Biochemistry 126 ( 1 ) 137 - 145 1999

Language：English Publishing type：Research paper (scientific journal) Publisher：Japanese Biochemical Society

Connective tissue growth factor (CTGF) is a novel cysteine-rich, secreted protein. Recently, we found that inhibition of the endogenous expression of CTGF by its antisense oligonucleotide and antisense RNA suppresses the proliferation and migration of vascular endothelial cells. In the present study, the following observations demonstrated the angiogenic function of CTGF in vitro and in vivo: (i) purified recombinant CTGF (rCTGF) promoted the adhesion, proliferation and migration of vascular endothelial cells in a dose-dependent manner under serum-free conditions, and these effects were inhibited by anti-CTGF antibodies
(ii) rCTGF markedly induced the tube formation of vascular endothelial cells, and this effect was stronger than that of basic fibroblast growth factor or vascular endothelial growth factor
(iii) application of rCTGF to the chicken chorioallantoic membrane resulted in a gross angiogenic response, and this effect was also inhibited by anti-CTGF antibodies. (iv) rCTGF injected with collagen gel into the backs of mice induced strong angiogenesis in vivo. These findings indicate that CTGF is a novel, potent angiogenesis factor which functions in multi-stages in this process.

DOI： 10.1093/oxfordjournals.jbchem.a022414

Cyclic mechanical stress induces extracellular matrix degradation in cultured chondrocytes via gene expression of matrix metalloproteinases and interleukin-1

Takuo Fujisawa, Takako Hattori, Kojiro Takahashi, Takuo Kuboki, Atsushi Yamashita, Masaharu Takigawa

Journal of Biochemistry 125 ( 5 ) 966 - 975 1999

Language：English Publishing type：Research paper (scientific journal) Publisher：Japanese Biochemical Society

To clarify the mechanism of cartilage degradation induced by mechanical stress, we investigated the influence of cyclic tension force (CTF) on the metabolism of cultured chondrocytes. The chondrocytes were exposed to CTF using a Flexercell strain unit. Five or 15 kPa of high frequency CTF significantly inhibited the syntheses of DNA, proteoglycan, collagen, and protein. Fifteen kPa of high frequency CTF induced the expression of interleukin-1 (IL-1), matrix metalloproteinase (MMP)-2 and -9 mRNA, and increased the production of pro- and active-MMP-9. The degradation of proteoglycan was inhibited by and MMP inhibitor, indicating that MMPs are involved in the degradation of proteoglycans induced by high frequency CTF. Moreover, reducing the frequency of CTF from high to low decreased the inhibition of proteoglycan synthesis. These findings suggest that the CTF frequency is one of the key determinants of chondrocyte metabolism. Low magnitude CTF, whether high or low frequency, did not cause the gene expression of cartilage degradation factors, suggesting that this CTF magnitude causes only minor changes in the cartilage matrix. High magnitude and frequency CTF caused the gene expression of IL-1 and MMP-9, followed by increases in the production of MMP-2 and -9 proteins, suggesting that excessive and continuous cyclic mechanical stress induces the production of IL-1 and MMP-9, resulting in cartilage degradation.

DOI： 10.1093/oxfordjournals.jbchem.a022376

The effects of sustained incisal clenching on the temporomandibular joint space

Y. Takenami, T. Kuboki, C. O. Acero Jr., K. Maekawa, A. Yamashita, Y. Azuma

Dentomaxillofacial Radiology 28 ( 4 ) 214 - 218 1999

Language：English Publishing type：Research paper (scientific journal) Publisher：Nature Publishing Group

Objective: To determine the effect of sustained incisai clenching on the width of the temporomandibular joint space. Methods: Nine normal subjects clenched on an anterior appliance for 10 min at 49 N. Sagittal tomograms were obtained during comfortable closure in the intercuspal position (ICP) (ICP- Before), comfortable closure on bite force transducer without clenching (BFT-Before), start of clenching (BFT-0), end of 5 min clenching (BFT-5), end of 10 min clenching (BFT-10), comfortable closure on the bite force transducer immediately after clenching (BFT-After) and comfortable closure in ICP after clenching (ICP-After). Joint space dimensions were automatically measured by a computerized image analysis system. Results: The minimum joint space dimension was significantly reduced at BFT-5 (P = 0.0381), BFT-10 (P = 0.0019) and BFT-After (P = 0.0053) in relation to BFT-Before. The condylar position was also significantly shifted upward at BFT-0 (P = 0.0422), BFT-5 (P = 0.0005), BFT- 10 (P = 0.0001), and BFT-After (P = 0.0004) in relation to BFT-Before. Conclusion: Sustained incisai clenching at 49 N causes significant anterior joint space reduction. We believe this is due to marked compression of the articular cartilage and disc.

DOI： 10.1038/sj.dmfr.4600443

Effect of Occlusal Appliances and Clenching on the Internally Deranged TMJ Space

Takuo Kuboki, Yasushi Takenami, Maria G. Orsini, Kenji Maekawa, Atsushi Yamashita, Yoshiharu Azuma, Glenn T. Clark

Journal of Orofacial Pain 13 ( 1 ) 38 - 48 1999

Language：English Publishing type：Research paper (scientific journal)

Aims: Stabilization appliances and mandibular anterior repositioning appliances have been used to treat patients with internal derangement of the temporomandibular joint (TMJ) based on the assumption that these appliances work by decompressing the TMJ. The purpose of this study was to indirectly test this assumption. Methods: Bilateral TMJ tomograms of 7 subjects with unilateral anterior disc displacement without reduction (ADDwor) were taken during comfortable closure and during maximum clenching in maximum intercuspation
tomograms were also taken with the 2 types of occlusal appliances in use. Outlines of the condyle and the temporal fossa were automatically determined by an edgedetection protocol, and the minimum joint space dimension of the joints with and without ADDwor was automatically measured for each experimental condition as the outcome variable. Results: Upon comfortable closure and maximum clenching, the minimum joint space dimensions of the ipsilateral and contralateral joints with the use of stabilization appliances and mandibular anterior repositioning appliances were not significantly different from those seen in maximum intercuspation. Conclusion: These findings do not indicate that these appliances induce an increase in joint space during closing and clenching in joints with ADDwor.