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1.
Abstract. The aim of this study was to compare changes in periodontal status in a Swedish poplation over a period of 20 years. Cross-sectional studies were carried out in Jönköping County in 1973, 1983, and 1993. Individuals were randomly selected from the following age groups: 20, 30, 40, 50, 60, and 70 years. A total of 600 individuals were examined in 1973, 597 in 1983, and 584 in 1993. The number of dentate individuals was 537 in 1973, 550 in 1983, and 552 in 1993. Based on clinical data and full mouth intra-oral radiographs, all individuals were classified into 5 groups according to the severity of the periodontal disease experience. Individuals were classified as having a healthy periodontium (group 1). gingivitis without signs of alveolar bone loss (group 2), moderate alveolar bone loss not exceeding 1/3 of the normal alveolar bone height (group 3), severe alveolar bone loss ranging between 1/3 and 2/3 of the normal alveolar bone height (group 4), or alveolar bone loss exceeding 2/3 of the normal bone height and angular bony defects and/or furcation defects (group 5). During these 20 years, the number of individuals in groups 1 and 2 increased from 49%. in 1973 to 60% in 1993. In addition, there was a decrease in the number of individuals in group 3, the group with moderate periodontal bone loss. Groups 4 and 5 comprised 13% of the population and showed no change in general between 1983 and 1993. The individuals comprising these groups in 1993, however, had more teeth than those who comprised these groups in 1983; on the average, the individuals in disease group 4 had 4 more teeth and those in disease group 5, 2 more teeth per subject. ID 1973, these 2 groups were considerably smaller, probably because of wider indications for tooth extractions and fewer possibilities for periodontal care which meant that many of these individuals had become edentulous and were not placed in a group. Individuals in groups 3, 4, and 5 were subdivided according to the number of surfaces (%) with gingivitis and periodontal pockets (≥4 mm). In 1993, 20%, 42%, and 67% of the individuals m groups 3, 4, and 5 respectively were classified as diseased and in need of periodontal therapy with >20% bleeding sites and >10% sites with periodontal pockets ≥4 mm. In conclusion, an increase in the number of individuals with no marginal bone loss and a decrease in the number of individuals with moderate alveolar bone loss can be seen. The prevalence of individuals in the severe periodontal disease groups (4, 5) was unchanged during the last 10 years; however, the number of teeth per subject increased.  相似文献   

2.
The aim of the present retrospective study was to evaluate alterations of the alveolar bone level over a 10-year period at tooth sites with "angular" and "even" patterns of bone loss, in subjects who were not exposed to systematic periodontal therapy. A further objective was to evaluate whether the presence of an angular defect can serve as a predictor of additional bone loss. 201 subjects in ages 25-70 years were examined radiographically on 2 occasions 10 years apart. 194 were dentate on the 2nd examination. The radiographic bone height at the mesial and distal aspect of all teeth was assessed by measuring the distance between the cemento-enamel junction and the bone crest. The morphologic pattern of alveolar bone loss at baseline was assessed for each tooth site. Angular defects were classified as degree 1, 2 and 3, according to increasing defect depth. The change in periodontal bone height over the 10-year period was calculated for each site. The results demonstrated an increased frequency of tooth loss among teeth showing presence of an angular bony defect at baseline; whereas 13% of the teeth with an even pattern of bone loss were lost between the 2 examinations, this proportion was 22%, 46% and 68% for teeth with an angular defect of degree 1, degree 2 and degree 3, respectively. Longitudinal bone loss of greater than or equal to 2 mm occurred more often among sites showing an angular defect when compared to sites with an even alveolar bone morphology.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
The present retrospective study was performed to evaluate some long-term alterations of the alveolar bone level at periodontal sites with angular and even ("horizontal") patterns of bone loss. The investigation included 48 patients who, following treatment for advanced periodontal disease, were placed in a maintenance care program which included recall appointments every 3-6 months for a period of 5 to 16 years. The material of the study comprised all teeth at which angular osseous defects (test sites) could be detected in a full-mouth series of radiographs obtained at the end of the active treatment phase. Alterations in the position of the marginal alveolar bone crest and the base of the osseous defect which took place during the maintenance period were assessed by comparing the post-treatment radiographs with a 2nd set of radiographs obtained at the final examination. In the same patients, an equal number of contralateral or neighboring teeth at which bone loss in the radiographs had an even or "horizontal" character were included as controls. The results from the assessments demonstrated that periodontal sites which, following active therapy displayed either angular or "horizontal" patterns of alveolar bone loss underwent, during a 5-16 year period of maintenance, only minor bone level alterations. Additional loss of supporting bone occurred equally frequently at sites with "horizontal" and angular patterns of bone loss. Thus, the findings reported failed to show up sites with angular bony defects as being particularly susceptible to recurrent destructive periodontitis.  相似文献   

4.
The purpose of this investigation was to examine the regeneration of alveolar bone following surgical and non-surgical periodontal treatment. A total of 16 patients who had advanced periodontitis and demonstrated angular bony defects on radiographs participated in the study. After the initial examination, they received instruction in oral hygiene and had their teeth thoroughly scaled. When the individual patient at 2 succeeding appointments had plaque on less than 20% of the tooth surfaces, one maxillary and one mandibular quadrant was treated with the modified Widman flap procedure while one of the remaining quadrants was treated with the reverse bevel flap procedure. The last quadrant was treated with root planing under local anesthesia. None of these procedures included bone contouring. Following treatment, the patients were recalled every 2 weeks for professional tooth cleaning. Radiographs taken 12 months following treatment revealed that only minor changes in the bone level had occurred in areas with horizontal bone loss following the various treatment modalities. Following the modified Widman flap procedure, however, a statistically significant coronal regrowth of bone (0.5 mm) had occurred in angular bony defects. The majority of the angular bony defects persisted following all 3 treatment modalities.  相似文献   

5.
Abstract The present study used radiographic assessments to evaluate the pattern of destructive periodontal disease in a rural and an urban sample of 25—64 year old Greek adults. The rural sample (A) comprised 190 subjects and the urban sample (B) 400 subjects. 13% of the subjects in sample A and 8% in sample B were edentulous. Full-mouth intraoral radiographs were obtained from the 503 dentate subjects and were examined with respect to (i) number and type of teeth present, and (ii) alveolar bone level (ABL), i.e., the distance between the cementoenamel junction and the alveolar bone crest at the approximal tooth surfaces. The results revealed that alveolar bone loss was ubiquitous in both samples. Pronounced bone loss, however, (i.e., a subject mean ABL of >6 mm) affected 18% (sample A) and 8% (sample B) of the individuals. Although an ABL of >6 mm was scored at 7.2 sites/subject in sample A and at 4.5 sites/subject in sample B, more than 10 such sites were found in 23% (A) and 11% (B) of the examined subjects. 25%) of the subjects in the rural sample (A) and 12% in the urban sample (B) accounted for 75% of the total number of tooth sites with pronounced bone loss. Multiple regression revealed that age and number of remaining teeth were the parameters most strongly correlated with the amount of bone loss on both the individual subject and the tooth site level. The present findings (i) demonstrated a high prevalence and severity of destructive periodontal disease in these 2 samples, and (ii) confirmed the skewed distribution of advanced disease in the population.  相似文献   

6.
Abstract The present investigation was performed in the Rhesus monkey to determine the effect of the modified Widman flap procedure on the level of the connective tissue attachment and supporting alveolar bone. Two adult male Rhesus monkeys were used. Eighteen contralateral pairs of periodontal pockets were produced in a standardized manner. Surgical treatment of the pockets was performed around experimental teeth and the contra-lateral teeth were used as the unoperated controls. Twelve months following treatment the animals were sacrificed and histological sections obtained. Using the cemento-enamel junction (CEJ) as a fixed reference point, linear measurements along the. root surface were made to the most apical cells of the junctional epithelium (JE), to the crest of the inter-proximal alveolar bone (CR), and to the apical extent of angular bony defects (AAD). These measurements from operated and unoperated pockets were then compared. The data revealed that treatment of periodontal pockets using the modified Widman flap procedure produced no gain in connective tissue attachment and no increase in crestal bone height. In angular bony defects a certain degree “bone fill” was noted. This bone repair was never accompanied by new connective tissue attachment.  相似文献   

7.
Mineral status of skeleton and advanced periodontal disease   总被引:3,自引:0,他引:3  
Abstract Studies of the effect of general bone loss on periodontal condition and on development of periodontal pockets suggest that there is no clear correlation between periodontal health or number of teeth and the general mineral status of the skeleton. In some reports, however, deep periodontal pockets have been correlated with good mineral status in the jawbones and skeleton. The purpose of this study of 227 healthy postmenopausal women aged 48 to 56 years was to determine whether advanced alveolar bone loss, diagnosed by panoramic radiographs, and periodontal probing depths or number of remaining teeth were correlated with the bone mineral status of the skeleton and cortical bone in the mandible. The results suggest that individuals with high mineral values in the skeleton seem to retain their teeth with deep periodontal pockets more easily than those with osteoporosis. This finding may especially motivate treatment of persons suffering from advanced periodontal disease but having good mineral status.  相似文献   

8.
The present study was undertaken since conflicting evidence exists regarding the effect of such tooth movement on levels of connective tissue attachment. Localized intrabony pockets were produced around isolated incisors in four rhesus monkeys. The root surfaces were planned to the level of the bone at the base of the angular bony defects. An oral hygiene regime was begun and continued for the remainder of the study. The experimental teeth were moved orthodontically into, and through, the original area of the intrabony defect. Two months after cessation of active tooth movement, block specimens were removed for histologic analysis. Control specimens comprised those teeth with induced periodontal defects, but without tooth movement. In specimens not subjected to tooth movement, angular bony defects were present and epithelium lined the root surface to the apical extent of instrumentation. The alveolar bone adjacent to the orthodontically moved teeth no longer had angular defect morphology. On the pressure side, epithelium lined the root surface, was interposed between root surface and bone and terminated at the apical limit of root instrumentation. On the tension side, the crest of the bone was located apical to the level of root planing, and epithelium lined the instrumented portion of the root surface. It was concluded that orthodontic tooth movement into intrabony periodontal defects was without effect upon the levels of connective tissue attachment.  相似文献   

9.
Abstract The aim of this investigation was to study the periodontal status at the ages of 15 and 20 years in the same individuals. Gingival and periodontal data from 100 adolescents in 1973 constituted the basic material. Eighty subjects could rereexamined in 1978. The mean number of teeth per subject was 27.1 both in 1973 and in 1978. Three individuals in 1973 and two in 1978 had no bleeding gingival units. There was a decrease between 1973 and 1978 in the number of subjects with a high number of inflamed gingival units. The buccal and lingual surfaces also showed lower prevalence of gingivitis, while the proximal surfaces showed a slight increase in prevalence. The prevalence of surfaces with plaque in 1978 was decreased for buccal and lingual surfaces but slightly increased for proximal surfaces. Sixty-six individuals in 1973 and 71 in 1978 had no pocketing. Altogether 75 tooth surfaces with pocketing were diagnosed in 1973 and 21 in 1978. Most of the pockets were located at the proximal surfaces of the molars. Four individuals with infra bony defects in one to two sites were found in 1973 and five in 1978. No progression of the bony defects found in 1973 seemed to have occurred during the 5-year period. In spite o(the frequent proximal areas with gingivitis, very few 20-year-olds showed signs of marginal bone loss, which indicates that gingivitis does not necessarily lead to destructive periodontitis in young people.  相似文献   

10.
Abstract. The present study was carried out in a private periodontal practice. 8 clinical criteria were chosen to select patients for microbiological examination. These criteria characterize prominent features of disease which at the start, during, or in the maintenance phase of treatment suggest difficulties in the progress of the periodontal therapy. Based on these clinical characteristics, an inventory was made of the prevalence of the 3 putative periodontal pathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia. Out of 320 referred patients 91 patients did meet 1 of the clinical criteria and consequently were selected for microbiological examination. Results showed that young patients (19–30 years) with periodontitis demonstrated the presence of A. actinomycetemcomitans more often (69%: p (0.005) compared to older age cohorts. A. actinomycetemcomitans was found more often when localized breakdown (in particular in the 1 st molar and incisor region) was observed and in patient who responded poorly to scaling and rootplaning. P. gingivalis and P. intermedia were most frequently recovered in patients showing primarily a bone loss pattern of angular defects of 5 mm. Retrospectively, these patients were further categorized, based on full mouth radiographs, in (1) patients with primarily horizontal bone loss and (2) patients with primarily angular bony defects. Results showed that A. actinomycetemcomitans occurred less frequently in patients showing horizontal bone loss ( p (0.05).  相似文献   

11.
The combined effects of plaque and physical stress on periodontal tissues   总被引:1,自引:0,他引:1  
Experiments have been performed in beagle dogs in attempts to evaluate the effect of orthodontic- and jiggling-type trauma on the supporting structures of premolars. The results reported have unanimously demonstrated that in situations where orthodontic or jiggling forces were inflicted on teeth with a normal periodontium, or on teeth with overt signs of gingivitis, the periodontal ligament tissue reacted by transitory signs of inflammation. These phenomena occurred without a concomitant loss of connective tissue attachment and development of pathologically deepened periodontal pockets. If the jiggling trauma was inflicted on teeth with an ongoing plaque-associated, destructive periodontitis, the resulting inflammatory reactions caused enhanced loss of attachment and angular bony defects. Furthermore, orthodontic tilting movements of teeth (intrusion) in a plaque-infected dentition may shift a supragingivally located plaque into a subgingival position resulting in periodontal tissue breakdown.  相似文献   

12.
Objectives: This retrospective study described the pattern of bone loss around teeth with endodontic posts in periodontitis patients, and compared it with contra-lateral teeth without posts.
Material and Methods: From full-mouth radiographic surveys of 146 periodontitis patients (35 years), 194 roots with endodontic posts and contra-laterals without posts were selected. Upper molars, pre-molars with two posts and roots of lower molars with two posts were excluded. Technical parameters of the post space preparation, endodontic and restorative status were evaluated. The level of alveolar bone measured in millimetre from the cemento-enamel junction (CEJ)/restoration margin and the pattern of bone loss (angular/horizontal) were evaluated on both mesial and distal aspects of roots with posts and contra-laterals, but not on the furcal areas of lower molars.
Results: The distance from the bone level to the CEJ/restoration margin was similar for teeth with posts and contra-laterals. However, teeth with posts had more angular defects mesially (18.8% versus 7.3%) as compared with their contra-laterals without posts. The defects around teeth with posts appeared to be typical in the sense that their apical level approximated the tip of the endodontic post.
Conclusion: In periodontitis patients, teeth restored by an endodontic post had angular bony defects on the mesial aspect more frequently in comparison with their contra-laterals.  相似文献   

13.
A clinical trial was undertaken to study the healing capacity of the periodontal tissues following different modes of periodontal surgery in patients whose oral hygiene was professionally maintained at an optimal level. Fifty patients, distributed into five groups, participated in the study. Following an initial examination and presurgical treatment, the various patient groups were subjected to one of the following surgical procedures: 1) the apically repositioned flap operation including elimination of bony defects, 2) the apically repositioned flap operation including curettage of the bony defects but without removal of bone, 3) the "Widman flap" technique including elimination of bony defects, 4) the "Widman flap" technique including curettage of the bony defects but without removal of bone, 5) gingivectomy including curettage of the bony defects but without removal of bone. After surgery, all patients received oral hygiene instruction and professional cleaning of the teeth once every 2 weeks during a 2-year period. The results showed that periodontal disease can be cured and further destruction of the periodontal tissues avoided irrespective of the surgical technique utilized for pocket elimination. Different surgical techniques, however, promoted varying degrees of regeneration of the supporting tissues. The most favourable healing was obtained when resection of bone was avoided and when complete coverage of the alveolar bone was ensured.  相似文献   

14.

Objectives

The objective of this study is to develop a new approach for radiographically measuring circumferential periodontal bone level using cone beam CT (CBCT) data. Accuracy and precision were assessed using direct probe measurements on a human skull as a reference.

Materials and methods

Digital quantification of circumferential periodontal bone levels was conducted considering bone level measurements, infrabony crater, and furcation detection. For this purpose, a human bony cadaver skull with a restoration free dentition was used, showing periodontal bony defects of teeth 15-17,25-27,35-37,45-47 (FDI classification). Image datasets were acquired using a Promax 3D CBCT device (Planmeca Oy, Helsinki, Finland) at 80 kV and 8 mA, 160 μm voxel size. Circumferential radiographic measurements between cemento-enamel junction and the alveolar crest for the mesial, central, and distal bone levels on the oral and vestibular sides of the examined teeth were carried out based on a prototype of specifically developed software. The measurements were performed by an expert panel of three independent, calibrated, and blinded observers. Manual probe measurements of the periodontal bone loss served as reference standard.

Results

The adopted software allowed the quantification of periodontal bone loss at all examined teeth. Overall deviation between radiographic and manual measurements of the observers ranged between 0.36 and 0.69 mm; hereby, 83 % of all results were <0.5 mm. Comparing overall accuracy between the ten turns of radiological measurements, accuracy for all observers ranged from 0.29 to 0.46 mm. The present study design showed a 100 % detection of furcation involvement for radiographic evaluation.

Conclusions

The adoption of a special measurement procedure in terms of a 3D coordinate system, which is placed through and perpendicular to the long axis of the tooth, allows consistent measurement positions of the mesial, central, and distal bone levels both for the oral and vestibular sides of the alveolar crest. In this way, reliable and reproducible quantification of circumferential periodontal bone loss using CBCT data with standardized resolution of 160 μm can be performed in all three dimensions.

Clinical relevance

This new approach of radiographically assessing circumferential periodontal bone level using CBCT data shows a first promising attempt of accurate detection of periodontal bony defects. Yet, possible negative impact of further clinical parameters in terms of artifact occurrence will have to be furthermore carefully investigated.  相似文献   

15.
目的 :回顾分析配合引导性组织再生术 (guidedtissueregeneration ,GTR)治疗对伴牙槽骨缺损的脱位再植牙的临床疗效的影响 ,为引导牙周组织再生的进一步研究提供经验。方法 :收集 1996年~ 2 0 0 3年间伴牙槽骨缺损、再植术中配合了GTR术治疗的完整病历资料 ,对其临床治疗情况及近远期疗效作回顾性研究分析。结果 :共收集到 2 3份符合条件的病历 (6 4颗再植牙 ) ,疗效分析结果表明 ,患牙术后 12个月探诊深度均显著减少 ,附着水平均显著获得 ;无论脱位时间长短 ,术后牙松动、牙根吸收和失牙的发生率均较高。伤后 6h内就诊脱位牙直接再植后 ,牙髓坏死率 77.5 % ,牙根吸收和失牙率与伤后就诊超过 6h组有显著性差异 (P <0 .0 1)。结论 :伤后就诊时间影响再植牙治疗效果 ,配合单纯GTR治疗 ,伴牙槽骨缺损的脱位再植牙的远期疗效仍然较差 ,利用GTR技术促进牙周组织再生特别是促进牙周缺损的再生需要进一步的基础与临床研究。  相似文献   

16.
This study radiographically evaluated the correlation between the changes in alveolar bone level occurring in bony defects after periodontal therapy and the corresponding pretreatment defect angles. The defect angle was defined by the bony defect surface and the root surface. The changes were determined from identically exposed and processed radiographs obtained just prior to surgery and 15 to 18 months later. The defect angle was clearly correlated to the radiographic changes in alveolar bone level. Most defects with an angle less than 45 degree showed a gain of bone while defects with the largest defect angles showed a loss. In addition, defects on root surfaces without furcations showed better healing than defects associated with furcations.  相似文献   

17.
ABSTRACT: Alveolar bone augmentation for dental implant rehabilitation is one of the greatest challenges for oral and maxillofacial surgeons. Bringing out an inadequate quantity of vertical bone during augmentation compromises correct implant positioning and the resulting prosthetic restoration. Alveolar distraction osteogenesis is now generally used in correcting alveolar ridge atrophy due to trauma, congenital defects, or periodontal defects. Onlay block grafting is a suitable method for restoring the alveolar bony defects. However, it sometimes can become a complicated procedure to repair the horizontal defect accompanying a vertical defect using only bone blocks. This clinical report presents a successful reconstruction of a severe anterior mandibular alveolar bony defect as a result of impacted teeth extraction and periodontal problem in a 50-year-old healthy female patient. The defect was reconstructed with symphysis graft and platelet-rich fibrin in the first step. Vertical alveolar distraction was performed on the grafted site to maintain the suitable bony height 3 months later. Grafted bony segment distraction and the treatment options in similar cases were also discussed in this clinical report among with the literature.  相似文献   

18.
The aim of this study was to compare changes in periodontal status of a Swedish population over a 10-year period expressed as frequency distributions of individuals according to severity of periodontal disease experience. The study involved 600 randomly selected individuals evenly distributed into age groups 20, 30, 40, 50, 60 and 70 years, examined in 1973 and another randomly selected group of 597 individuals similarly age distributed and examined in 1983. Based on clinical data and full mouth intraoral radiographs all individuals were classified into 5 groups according to severity of periodontal disease experience. In 1983, 23% of the individuals were classified as having healthy periodontal tissues, group 1, compared to 8% in 1973. The changes were most pronounced in the age groups 20 and 30 years, among whom 58% and 35%, respectively, were registered as having healthy periodontium in 1983. The prevalence of individuals with gingivitis without signs of lowered periodontal bone level, group 2, was 22% in 1983 compared to 41% in 1973. In all, 49% of the dentate population in 1973 and 45% in 1983 showed no marginal alveolar bone loss. Moderate periodontal bone loss, group 3, was found in 41% of the population in 1983 compared to 47% in 1973. Among 30-, 40-, and 50-year-olds, there were more, and among 60- and 70-year-olds, fewer individuals in this group in 1983 compared to 1973. 96% of the dentate population were classified as belonging to groups 1, 2 or 3 in 1973 compared to 86% in 1983.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
Extraction of teeth with severe attachment loss ("hopeless" teeth) is common practice in the dental office. Recent evidence questions the validity of this approach. The purpose of the present study was to examine the alveolar bone changes adjacent to "hopeless" teeth with and without extraction. A total of 145 teeth from 129 patients were included in this retrospective study. Teeth were defined as "hopeless" when Class III furcation involvement was present, or when alveolar bone loss exceeded 50%. Patients were pooled into two groups: A, 82 "hopeless" teeth (71 patients) that were retained throughout the experimental period, and B, 63 "hopeless" teeth (58 patients) that were extracted. The average observation period was 4 years with a minimum of 2 years. Alveolar bone changes were measured as a percentage of the anatomic root (radiographic apex-CEJ) using a Schei ruler. Results revealed significantly greater bone loss adjacent to teeth flanking retained "hopeless" teeth, 3.12% per year, at a rate 10 times that of the 0.23% annual bone loss in teeth flanking "hopeless" teeth that were extracted (P less than 0.0001). This study confirms that without periodontal treatment, the retention of teeth with severe periodontal breakdown has a negative effect on the adjacent teeth.  相似文献   

20.
Abstract. Studies have shown that <20% of the US population has periodontal disease. Studies of radiographs have shown that alveolar bone loss increases with age. Bone loss assessed from intraoral radiographs describing 10,282 teeth from 416 subjects seeking dental care during a 3 month period at the University of Washington were studied. The mean age of the subjects was 47.2 years (SD±15.2). The youngest subjects (15–24) had on average 29.6 teeth (SD±2.2) and the oldest subjects (75–94) 19.3 teeth (SD±6.6). This difference was statistically significant ( F =16.57. p <0.00l). No association was found between alveolar bone loss (CEJ-ABC). and TMD symptoms. Smoking was significantly associated with both general bone loss (CEJ-ABC) ( x 2=114.9. p <0.0001), and vertical bone defects (angular) ( x 2= 101.8. p <0.0001). In this study population (15–94 years), alveolar bone loss progressed as defined by the slope (β=0.29) between age 15–34, but was almost flat from age 50 years (β=0.04). The data suggested an overall rate of alveolar bone loss of 0.02 mm per year. Stepwise multiple regression analysis showed that smoking was the primary factor in bone loss ( t =7.7, p <0.0001), followed by age ( t =7.0. p<0.001) and gender ( t =3.0. p <0.01). TMD symptoms could not explain the presence and severity of horizontal or vertical defects. If the CEJ-ABC distance above the mean plus 2× the SD was used as the cutoff value to define abnormal bone levels. 10.9% of the younger (15–45 years), and 10.7%) of the older subjects (50–94) had significant alveolar bone loss. 73.9% of the younger and 100% of the older subjects with such extent of alveolar bone loss were smokers.  相似文献   

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