ABSTRACT
The purpose of this study was to evaluate whether the cranial and circumaxillary sutures react differently to maxillary expansion (ME) and alternate maxillary expansions and constrictions (Alt-MEC) in a rat model. Twenty-two male Sprague-Dawley rats (6 weeks old) were used and divided into three groups. In ME group (n=9), an expander was activated for 5 days. In Alt-MEC group (9 animals), an alternate expansion and constriction protocol (5-day expansion and 5-day constriction for one cycle) was conducted for 2.5 cycles (25 days total). The control group comprised 4 animals with no appliances used, each of two sacrificed on day 5 and day 25 respectively. Midpalatal suture expansion or constriction levels were assessed qualitatively and quantitatively by bite-wing X-rays and cast models. Distances between two central incisors and two maxillary first molars were measured on cast models after each activation. Circumaxillary sutures (midpalatal, maxillopalatine, premaxillary, zygomaticotemporal and frontonasal suture) in each group were characterized histologically. Results showed that midpalatal suture was widened and restored after each expansion and constriction. At the end of activation, the widths between both central incisors and first molars in Alt-MEC group were significantly larger than those in ME group (P<0.05). Histologically, all five circumaxillary sutures studied were widened in multiple zones in Alt-MEC group. However, only midpalatal suture was expanded with cellular fibrous tissue filling in ME group. Significant osteoclast hyperplasia was observed in all circumaxillary sutures after alternate expansions and constrictions, but osteoclast count increase was only observed in midpalatal suture in ME group. These results suggested that cranial and circumaxillary sutures were actively reconstructed after Alt-MEC, while only midpalatal suture had active reaction after ME.
ABSTRACT
The purpose of this study was to evaluate whether the cranial and circumaxillary sutures react differently to maxillary expansion (ME) and alternate maxillary expansions and constrictions (Alt-MEC) in a rat model. Twenty-two male Sprague-Dawley rats (6 weeks old) were used and divided into three groups. In ME group (n=9), an expander was activated for 5 days. In Alt-MEC group (9 animals), an alternate expansion and constriction protocol (5-day expansion and 5-day constriction for one cycle) was conducted for 2.5 cycles (25 days total). The control group comprised 4 animals with no appliances used, each of two sacrificed on day 5 and day 25 respectively. Midpalatal suture expansion or constriction levels were assessed qualitatively and quantitatively by bite-wing X-rays and cast models. Distances between two central incisors and two maxillary first molars were measured on cast models after each activation. Circumaxillary sutures (midpalatal, maxillopalatine, premaxillary, zygomaticotemporal and frontonasal suture) in each group were characterized histologically. Results showed that midpalatal suture was widened and restored after each expansion and constriction. At the end of activation, the widths between both central incisors and first molars in Alt-MEC group were significantly larger than those in ME group (P<0.05). Histologically, all five circumaxillary sutures studied were widened in multiple zones in Alt-MEC group. However, only midpalatal suture was expanded with cellular fibrous tissue filling in ME group. Significant osteoclast hyperplasia was observed in all circumaxillary sutures after alternate expansions and constrictions, but osteoclast count increase was only observed in midpalatal suture in ME group. These results suggested that cranial and circumaxillary sutures were actively reconstructed after Alt-MEC, while only midpalatal suture had active reaction after ME.
Subject(s)
Animals , Male , Rats , Mandible , Physiology , Masticatory Muscles , Physiology , Maxilla , Physiology , Range of Motion, Articular , Physiology , Rats, Sprague-DawleyABSTRACT
The aim of this retrospective study was to quantitatively evaluate the treatment effects of intrusion of overerupted maxillary molars using miniscrew implant anchorage and to investigate the apical root resorption after molar intrusion. The subjects included 30 patients whose average ages were 35.5±9.0 years. All patients had received intrusion treatments for overerupted maxillary molars with miniscrew anchorage. There were 38 maxillary first molars and 26 maxillary second molars to be intruded. Two miniscrews were inserted in the buccal and palatal alveolar bone mesial to the overerupted molar. Force of 100-150 g was applied by the elastic chains between screw head and attachment on each side. Lateral cephalograms and panoramic radiographs taken before and after intrusion were used to evaluate dental changes and root resorption of molars. Only 6 of the 128 miniscrews failed. The first and second molars were significantly intruded by averages of 3.4 mm and 3.1 mm respectively (P<0.001). The average intrusion time was more than 6 months. The crown of the molars mesially tilted by averages of 3.1 degrees and 3.3 degrees (P<0.001) for first and second molars. The amounts of root resorption were 0.2-0.4 mm on average. The intrusion treatment of overerupted molars with miniscrew anchorages could be used as an efficient and reliable method to recover lost restoration space for prosthesis. Radiographically speaking, root resorption of molars was not clinically significant after application of intrusive forces of 200 to 300 g.
ABSTRACT
The aim of this retrospective study was to quantitatively evaluate the treatment effects of intrusion of overerupted maxillary molars using miniscrew implant anchorage and to investigate the apical root resorption after molar intrusion. The subjects included 30 patients whose average ages were 35.5±9.0 years. All patients had received intrusion treatments for overerupted maxillary molars with miniscrew anchorage. There were 38 maxillary first molars and 26 maxillary second molars to be intruded. Two miniscrews were inserted in the buccal and palatal alveolar bone mesial to the overerupted molar. Force of 100-150 g was applied by the elastic chains between screw head and attachment on each side. Lateral cephalograms and panoramic radiographs taken before and after intrusion were used to evaluate dental changes and root resorption of molars. Only 6 of the 128 miniscrews failed. The first and second molars were significantly intruded by averages of 3.4 mm and 3.1 mm respectively (P<0.001). The average intrusion time was more than 6 months. The crown of the molars mesially tilted by averages of 3.1 degrees and 3.3 degrees (P<0.001) for first and second molars. The amounts of root resorption were 0.2-0.4 mm on average. The intrusion treatment of overerupted molars with miniscrew anchorages could be used as an efficient and reliable method to recover lost restoration space for prosthesis. Radiographically speaking, root resorption of molars was not clinically significant after application of intrusive forces of 200 to 300 g.
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Young Adult , Bone Screws , Cephalometry , Dental Implantation , Maxilla , Molar , Diagnostic Imaging , General Surgery , Orthodontic Anchorage Procedures , Methods , Radiography, Dental , Methods , Retrospective Studies , Root Resorption , Diagnostic Imaging , General Surgery , Tooth Movement Techniques , MethodsABSTRACT
<p><b>BACKGROUND</b>The prevalence of malocclusion in modern population is higher than that in the excavated samples from the ancient times. Presently, the prevalence of juvenile malocclusion in the early stage of permanent teeth is as high as 72.92% in China. This study aimed to observe and evaluate the prevalence and severity of malocclusions in a sample of Xia Dynasty in China, and to compare these findings with the modern Chinese population.</p><p><b>METHODS</b>The material consisted of 38 male and 18 female protohistoric skulls of Xia Dynasty 4000 years ago. Of 86 dental arches, 29 cases had the jaw relationships. Tooth crowding, diastema, individual tooth malposition and malocclusion were studied.</p><p><b>RESULTS</b>Of the samples, 23.3% showed tooth alignment problems including crowding (8.1%), diastema (9.3%), and individual tooth malposition (5.8%). The prevalence of malocclusion was 27.6%, mainly presented as Angle Class I.</p><p><b>CONCLUSIONS</b>It is indicated that over thousands of years from Neolithic Age (6000 - 7000 years ago) to Xia Dynasty (4000 years ago), the prevalence of malocclusion did not change significantly. The prevalence of malocclusion of Xia Dynasty samples was much lower than that of modern population.</p>
Subject(s)
Female , Humans , Male , China , Epidemiology , Diastema , History, Ancient , Malocclusion , Epidemiology , HistoryABSTRACT
<p><b>OBJECTIVE</b>To observe the changes of blood flow volume in mental artery of dog before and after osteocompression.</p><p><b>METHODS</b>16 adult dogs were selected and the osteocompressors were fixed on the right buccal side of the mandible. The osteocompressor was used to compress the mandible 1.0 mm per 3 days for totally 15 days. On the 1st, 15th, 45th and 90th day after osteocompression, the 4 MHz prober of color Doppler flow imaging machine was put on the surface of the mucosa below which there was the mental artery. The color Doppler flow imaging was used to measure the blood flow volume in the mental artery of both experimental and control sides.</p><p><b>RESULTS</b>1) The blood flow value in the mental artery was the lowest on the 15th day after osteocompression, however there was not significantly different before and after osteocompression. 2) Compared with the control, the blood flow value of the mental artery on the 1st day after experiment was significantly decreased. 3) Compared with the data before experiment, the deduction of the blood flow values between experimental side and control on the 1st, 15th and 45th day after osteocompression had significant differences. On the 90th day, the deduction of the blood flow value was similar to normal.</p><p><b>CONCLUSION</b>The osteocompression influences blood flow volume in mental artery temporarily, however, the influence is reversible and can be recovered by times after osteocompression.</p>
Subject(s)
Animals , Dogs , Arteries , Blood Flow Velocity , Head , MandibleABSTRACT
<p><b>OBJECTIVE</b>To investigate the morphology characters of upper airway and its surrounding tissues in different age non-snoring males.</p><p><b>METHODS</b>Total of 114 non-snoring males, with age-range from 22 to 78 year old, were included in this study. They were divided into 3 groups: 30 in younger group (22-29 years old), 57 in middle-aged group (36-57 years old), and 31 in aged group (70-78 years old). All subjects had magnetic resonance imaging scanning.</p><p><b>RESULTS</b>(1) The nasopharynx in aged group was statistically different from that of the younger group and the middle aged group. The volume of nasopharynx in aged group (7.81 +/- 1.59) cm3 (x +/- s, same herein after) is greater than that in younger group (4.89 +/- 1.20) cm3 and middle aged groups (6.06 +/- 2.07) cm3. (2) The AP diameter/transverse diameter of velopharynx, glossopharynx and laryngopharynx in the aged group tended to be smaller. The average value of AP diameter/transverse diameter of velopharynx in aged group is 0.46 +/- 0.14, while the value is 0.59 +/- 0.14 and 0.57 +/- 0.14 in middle and young groups respectively, compared with that of the aged group, there is statistical difference (P < 0.01). Further more, the min/max section area of velopharynx, glossopharynx, laryngopharynx in aged group are smaller than that of young group and midlife groups. (3) The aged group had the thinnest thickness of posterior and lateral velopharyngeal walls, but the largest volume of soft palate and fat pads among all groups.</p><p><b>CONCLUSIONS</b>In non-snoring males, there is more fat deposition around the upper airway with aging. While the large nasopharynx and large transverse diameter of upper airway seem to balance the disadvantaged changes and to benefit the their sleep respiration.</p>
Subject(s)
Adult , Aged , Humans , Male , Middle Aged , Young Adult , Aging , Magnetic Resonance Imaging , Nasopharynx , PharynxABSTRACT
<p><b>OBJECTIVE</b>To approach the correlation of upper airway and surrounding tissues with body mass index (BMI) of non-apnea aged males.</p><p><b>METHODS</b>Thirty-one non-apnea aged from 70 years to 84 years males (all were inspected by polysomnography and apnea hyponea index < 10 times/hour) had magnetic resonance imaging scanned. In images of MRI, the upper airway was divided into four sections, including nasopharynx, velopharynx, glossopharynx and laryn-gopharynx. The sizes, forms and surrounding tissues were measured and correlation analysis of duality vaniable about upper airway and surrounding tissues with BMI were carried out.</p><p><b>RESULTS</b>(1) The volume of nasopharynx had negative correlation with body mass(P < 0.05). (2) The min anterior-posterior diameter of velopharynx had positive correlation with body mass and BMI. The max value of anterior-posterior diameter/transverse diameter of velopharynx had positive correlation with body mass. The mi value of distance of fatpads had negative correlation with body mass and BMI. The min and average value of distance of ascending ramus had positive correlation with body mass and BMI. The mn value of distance of fatpads/distance of ascending ramus had negative correlation with body mass and BMI. The transverse diameter/lateral velopharyngeal wall of velopharynx had positive correlation with BMI. All of above results had statistic significance (P < 0.05). (3)The volume of soft palate, tongue and fatpads had no correlation with body mass and BMI (P > 0.05).</p><p><b>CONCLUSION</b>The forms of sectional areas of velopharynx are subjected to body mass, and with the increasing of body mass they tend to round. In non-apnea aged males, the distance of fatpads and ascending rami have intimate relationship with body mass and BMI. The volume of soft palate, tongue, tatpads and velopharyngeal walls has little things with hody mass and BMI.</p>
Subject(s)
Humans , Male , Apnea , Body Mass Index , Magnetic Resonance Imaging , Palate, Soft , Polysomnography , Sleep Apnea, Obstructive , TongueABSTRACT
Z2 appliance is the pre-adjusted appliance designed for Chinese orthodontic patients. The prescription of the appliance is based on Chinese normal occlusion, which is much different from the West in the first and the second orders as well as the third one. The appliance routinely includes 20 brackets and 8 molar buccal tubers with 3 standard arch forms. Clinically, continued light force is used in whole treatment. The side-effects such as forward tipping of incisors, bite deepening and loss of molar anchorage are reduced further due to fewer tips built into the anterior brackets as well as lower friction elastometric modules used during aligning and leveling. In condition of arch are leveled completely, 0.48 mm x 0.64 mm stainless steel archwire with 1.47 N retraction force is the best combination for sliding mechanics, which is proved by 3D nonlinear finite element study. Self drilling micro-screw is used for maximum anchorage. In finishing stage 0.53 mm x 0.64 mm NT arch wire is added in order to get full torque expressing. The research of Chinese pre-adjusted appliance has been lasted for more than 10 years in the department and clinical studies on Z2 appliance show that with minimal wire bending, treatment is more efficient and result is high quality and more consistent for Chinese orthodontic patients.
Subject(s)
Humans , Dental Occlusion , Friction , Incisor , Molar , Orthodontic Appliance Design , Orthodontic Brackets , Orthodontic Wires , Stainless SteelABSTRACT
<p><b>OBJECTIVE</b>To evaluate the effect of the preadjusted appliance (Z1 appliance) based on Chinese normal occlusion.</p><p><b>METHODS</b>Thirty non-extraction patients were treated with Z1 appliance. No wire bending was made during treatment. The results of these 30 cases had been evaluated by five senior orthodontists. Models were analysed quantitatively to testify and evaluate the efficiency of the appliance.</p><p><b>RESULTS</b>The average score for post-treatment models was 91.2 (total score was 100). The model measurements indicated that average projective distance on occlusal plane between proximal contact points of adjacent teeth was less than 0.3 mm, which demonstrated good alignment. The prominence of crowns was almost coincident with the data of Chinese normal occlusion. For the average tip of most teeth, there was no statistical difference between the study group and the normal control group. The crown torque variation tendency from anterior to posterior was similar to that in the subjects with normal occlusion. However, the cases treated with Z1 appliance achieved more negative torque in the lower posterior segment.</p><p><b>CONCLUSIONS</b>The result of the non-extraction patients treated with Z1 appliance was quite satisfied. Wire bending could be reduced during treatment. It was necessary to adjust the crown torque values for lower posterior teeth.</p>
Subject(s)
Adolescent , Child , Female , Humans , Male , Young Adult , Asian People , Dental Occlusion , Orthodontic Appliance Design , Orthodontic Appliances , Orthodontics, Corrective , MethodsABSTRACT
<p><b>OBJECTIVE</b>To study the ancient teeth helped us to acquaint with the evolution of oral diseases.</p><p><b>METHODS</b>Teeth and jaws excavated in Erlitou, Henan province and Youyao, Shanxi province were observed clinically with care. The total specimens included 56 individuals (38 males and 18 females, including 894 permanent teeth and 86 dental arches). The dental caries were observed. The incidence of dental caries was calculated.</p><p><b>RESULTS</b>The rate of dental caries was 6.9% in 894 observed teeth. The prevalence was 39% among individuals.</p><p><b>CONCLUSIONS</b>The rate of dental caries in ancient Chinese in Xia Dynasty was lower than that in modem people. There were more caries in elderly people while no sex difference was found in Chinese in Xia Dynasty, which was similar to the situation in modern society. Cervical caries was more common than occlusal caries. The second molars and the third molars were frequently involved, which was different from the phenomenon nowadays.</p>
Subject(s)
Adult , Female , Humans , Male , Archaeology , Asian People , Dental Caries , Epidemiology , PrevalenceABSTRACT
<p><b>OBJECTIVE</b>To investigate the changes in the disc-condyle-fossa relationship following mandibular advancement.</p><p><b>METHODS</b>Twenty-five patients (10 boys and 15 girls, 11.1 +/- 1.1 years) with class II division 1 malocclusions were treated with Activator. The average treatment time was 10.9 months. Parasagittal MRIs in closed mouth position were analyzed before and after Activator treatment by means of the pair-t test.</p><p><b>RESULTS</b>Ca-Tm value [(-0.1 +/- 1.5) mm and (-0.6 +/- 0.9) mm] of the left temporomandibular joint (TMJ) and Ca-Ca' value [(2.3 +/- 0.8) mm and (1.8 +/- 0.5) mm] of the right TMJ were changed significantly after Activator treatment (P < 0.05). This indicated that the condyle was located anteriorly in the fossa. No significant changes were found in the disc-fossa relationship and disc-condyle relationship (P > 0.05).</p><p><b>CONCLUSIONS</b>Activator could promote the growth of the mandible and at the same time, it had no apparent negative influence on TMJ function.</p>
Subject(s)
Adolescent , Child , Female , Humans , Male , Malocclusion, Angle Class II , Pathology , Therapeutics , Mandibular Advancement , Postoperative Period , Temporomandibular Joint , PathologyABSTRACT
<p><b>OBJECTIVE</b>To describe the morphology of upper airway in non-apnea males aged seventy years or over.</p><p><b>METHODS</b>Thirty-one non-apnea males aged 70 years or over [diagnosed by whole-night polysomnography (PSG), apnea and hypopnea index (AHI) < 10 per hour] had been taken magnetic resonance imaging (MRI) scanning.</p><p><b>RESULTS</b>The narrowest point of upper airway was at velopharynx. The mean and the minimum section areas were (190.9 +/- 67.1) mm(2) and (112.1 +/- 47.7) mm(2), respectively. Each sagittal/transverse ratio was between 0.22 and 0.89. It showed an ellipse-like cross-section of upper airway, while velopharynx was the most "slender" segment (sagittal/transverse-caliber was 0.22 - 0.71). The min/max section area of upper airway was between 0.38 and 0.62. It demonstrated that each airway segment was a "cone-like" form, while the velopharynx was the steepest segment.</p><p><b>CONCLUSIONS</b>In the non-apnea elderly males aged seventy years or over, the velopharynx was most likely to collapse.</p>
Subject(s)
Aged , Aged, 80 and over , Humans , Male , Magnetic Resonance Imaging , Palate, Soft , Pharynx , Polysomnography , Sleep Apnea, Obstructive , Surveys and Questionnaires , TongueABSTRACT
<p><b>OBJECTIVE</b>To observe the morphologic changes of inferior alveolar nerve before and after osteocompression on dog's mandible.</p><p><b>METHODS</b>8 dogs were selected and divided into 4 groups, 2 dogs per group. The osteocompressor was fixed on the right buccal side of the mandibule. Crew the compressor to compress the mandible 1.0 mm per 3 days for totally 15 days. On the 1st day, 15th day, 45th day and 90th day after osteocompression, the dogs of different groups were killed respectively. Get the inferior alveolar nerve and HE staining was carried on.</p><p><b>RESULTS</b>(1) On the 1st, 15th and 45th day after osteocompression, the fiber of the inferior alveolar nerve was obviously injured. (2) On the 90th day after osteocompression, the injured nerve was almost recovered to normal.</p><p><b>CONCLUSION</b>The osteocompression could cause temporary injury on the inferior alveolar nerve, but the injury was reversible and might recovere by times after osteocompression.</p>
Subject(s)
Animals , Dogs , Mandible , Mandibular NerveABSTRACT
<p><b>OBJECTIVE</b>To investigate the frequency, sex differences and location of impacted maxillary canine in orthodontic patients.</p><p><b>METHODS</b>Two hundred and fifteen patients (77 males and 138 females) with maxillary canine impaction were included in the study. The experimental group was gathered from the Department of Orthodontics, Peking University School and Hospital of Stomatology. CT scan images were evaluated. Chi-square test was used in the analysis.</p><p><b>RESULTS</b>The prevalence of maxillary canine impaction among Chinese orthodontic patients was 2.05%. The ratio between male and female was 1.8:1 and the ratio between buccal and palatal location was 2.1:1. Surgical exposure and orthodontic alignment had been predominant in such conditions. There was significant deference in the treatment between palatally impacted canine and buccally impacted one. More palatally impacted canines were extracted than buccally impacted ones.</p><p><b>CONCLUSIONS</b>There was significant difference in the treatment of maxillary canine impaction. More buccally impacted canines were found in Chinese patients, especially in female patients.</p>
Subject(s)
Adolescent , Adult , Child , Female , Humans , Male , Young Adult , Cuspid , Pathology , Maxilla , Orthodontics, Corrective , Sex Factors , Tooth, Impacted , Epidemiology , TherapeuticsABSTRACT
<p><b>OBJECTIVE</b>To investigate three-dimensional changes of maxilla after rapid maxillary expansion (RME).</p><p><b>METHODS</b>Ten patients treated with RME were included in the study. Spiral CT images were used to evaluate three-dimensional changes of the maxilla. A three-dimensional reference frame was set up.</p><p><b>RESULTS</b>(1) ANS, PNS' and PNS displaced downward and forward. ANS-PNS plane rotated clockwise in the mid-sagittal plane. ANS-PNS' plane, which represents the real position of maxilla, was not changed in the mid-sagittal plane. The palatal suture was expanded in taper shape and two halves of the maxilla rotated in the frontal plane. (2) The maxillary suture was opened wider in the middle and narrower at both ends, which was like a spindle.</p><p><b>CONCLUSIONS</b>Three-dimensional changes were found after RME treatment. Spiral CT was useful in the three-dimensional evaluation of maxilla.</p>
Subject(s)
Adolescent , Child , Female , Humans , Male , Maxilla , Diagnostic Imaging , Palatal Expansion Technique , Tomography, Spiral Computed , MethodsABSTRACT
<p><b>OBJECTIVE</b>To investigate the correlation between airflow ratio and craniofacial, airway and dental morphology.</p><p><b>METHODS</b>Seventy-two subjects aged 11 to 14 years were selected. The airflow ratio was measured by the system for the simultaneous measurement of oral and nasal respiration. Eighty-six variables of craniofacial, airway and dental morphology were acquired based on cephalometric films and models, from which 16 significant variables were selected. Multiple regression analysis (backward) and linear regression analysis were carried out in order to acquire morphological variables that had closer correlation with the airflow ratio.</p><p><b>RESULTS</b>Four variables were found to have closer correlated association with the airflow ratio (P < 0.05), which were ANS-Me/N-Me, Ar-Go-Me, P-T, SHJK orderly and the coefficients were 3.359, 0.012, -0.013 and -0.021, respectively.</p><p><b>CONCLUSIONS</b>Craniofacial morphology was related to the respiratory mode.</p>
Subject(s)
Adolescent , Child , Female , Humans , Male , Cephalometry , Facial Bones , Malocclusion , Diagnostic Imaging , Mouth , Mouth Breathing , Diagnostic Imaging , Pharynx , Radiography , ToothABSTRACT
<p><b>OBJECTIVE</b>To introduce a new modified twin-block advancement appliance and investigate the effects on respiratory variables in patients with OSAS.</p><p><b>METHODS</b>29 patients with OSAS participated in the study and were fitted with modified twin-block appliances to hold the mandible in an anterior and inferior position. Polysomnography was performed with and without appliance insertion. And questionnaires were used for registration of patients subjective symptoms. Pair-t analysis was used to evaluate the effects of appliances in patients with OSAS.</p><p><b>RESULTS</b>26 patients responded to the appliance therapy. Apnea-hypopnea index, apnea index and hypopnea index were reduced significantly (P < 0.01). Lowest arterial oxygen saturation improved significantly (P < 0.01). Discomfort with mandibular advancement disappeared within one week.</p><p><b>CONCLUSIONS</b>Modified twin-block advancement appliance is a conservative, successful treatment alternative that could benefit patients suffered from OSAS.</p>
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Orthodontic Appliance Design , Orthodontic Appliances, Removable , Sleep Apnea, Obstructive , Therapeutics , Treatment OutcomeABSTRACT
<p><b>OBJECTIVE</b>The research tended to approach applying of adjustable appliance in the treatment of obstructive sleep apnea-hypopnea syndrome (OSAHS).</p><p><b>METHODS</b>30 OSAHS patients (24 males and 6 females) participated in the adjustable group, with a mean age of (49.9 +/- 9.9) years old. AHI was (33.1 +/- 22.7) per hour. The control group consisted of 30 OSAHS patients wearing ordinary mandibular advancing appliance in the corresponding period, with age, weight and AHI at the same level. Monoblind way was designed to obtain and analyze the therapy differences. Differences in changes of upper airway, mandible and hyoid bone were also analyzed among the doctor-experience position, final adjusted position and original position.</p><p><b>RESULTS</b>AHI decreased by 85.5% in the adjustable appliance group. The change in AHI was greater significantly (P = 0.025) in the adjustable group than in the control group. In the final adjusted position, the amount of mandibular advancement was (5.8 +/- 1.4) mm [(71 +/- 26)% of the maximum range of protrusion] and that of bite opening (the distance between upper and lower incisor edges) was (4.6 +/- 1.1) mm.</p><p><b>CONCLUSIONS</b>The adjustable appliance had shown better therapy effect in OSAHS patients. The final adjusted position provided useful information on determining mandibular position using other appliances.</p>
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Mandibular Advancement , Single-Blind Method , Sleep Apnea, Obstructive , Therapeutics , Treatment OutcomeABSTRACT
<p><b>OBJECTIVE</b>To investigate the expression and the localization of Cathepsin K and IL-6 mRNA in root-resorbing tissue and to elucidate the molecular changes and mechanism of root resorption induced by tooth movement.</p><p><b>METHODS</b>Rats were subject to experimental tooth movement to induce root resorption. In situ hybridization was performed to identify the cells in root-resorbing tissue that produced Cathepsin K or IL-6 the difference of CK mRNA or IL-6 mRNA expression between root resorption group and control group was calculated by t-test.</p><p><b>RESULTS</b>Cathepsin K mRNA was highly and selectively expressed in multinuclear odontoclast and IL-6 mRNA expressed in fibroblast, osteoblast, osteocyte and cementoblast. The expression of Cathepsin K mRNA and IL-6 mRNA in root-resorbing tissue increased evidently compared with the normal periodontium.</p><p><b>CONCLUSIONS</b>Odontoclast in the root-resorbing tissue expresses Cathepsin K mRNA that participates in proteolysis during root resorption. IL-6 plays a very important role in the root resorption as a multifunctional cytokine.</p>