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1.
Abstract. The purpose of this study was to document and characterize epithelial remnants (EPRs) of the crestal periodontium of the deciduous dentition of a diphyodont and compare them with EPR units found in the corresponding area of the permanent dentition. 7 beagle dogs were used. At the age of 10 weeks (deciduous dentition) and 15 months (permanent dentition), respectively, a 6-week plaque control period was initiated. At the end of each plaque control period, biopsies were obtained from the mandibular 02P, 03P (deciduous dentition) and P3, P4 (permanent dentition) premolar regions and prepared for histologic analysis. 2 regions, (1) the supracrestal region and (2) the periodontal ligament region, were identified. The supracrestal region was divided into 4 compartments of equal height. The histologic parameters studied included the (i) EPR frequency: number of EPRs/mm of root length, (ii) EPR size, (iii) EPR-root distance, (iv) EPR-bone distance and (v) cell area. No differences were observed between the 2 dentitions with respect to the number, size and relative location of EPR units in the supracrestal regions or the periodontal ligament regions. Epithelial remnants of the supracrestal region in both dentitions tended to be more frequent, larger and positioned further from the root surface than the EPRs of the periodontal ligament region. EPR units of the periodontal ligament region were located significantly further from the bone in the deciduous dentition than in the permanent dentition. The cell area of EPRs did not differ between the 2 dentitions. It was concluded that EPRs are a normal component of the crestal periodontal tissues of the deciduous dentitions of the diphyodont beagle dog and they appear to be similar to those found in the permanent dentition of young dogs.  相似文献   

2.
Lately, it has been questioned whether localized juvenile periodontitis (LJP) is restricted to the permanent dentition, or if it sometimes might have a prepubertal onset, involving the primary dentition. To clarify this question, 17 patients with LJP, together with 17 non-LJP matched controls, were retrospectively examined for radiographic signs of alveolar bone destruction in their primary dentitions. All LJP subjects but one showed localized marginal bone loss, whereas no bone loss was observed among the controls. The results suggest that at least some cases of LJP start in the primary dentition prior to the involvement of the permanent teeth.  相似文献   

3.
Of 49,380 male naval recruits who were screened for juvenile periodontitis (JP), 270 were clinically diagnosed as having the disease. Full-mouth radiographs identified 182 of these 270 patients as having JP with extensive bone loss on permanent first molars and/or incisors. These 182 patients, 137 (75.3%) of whom were black, were further classified into Type I: bone loss involving first molars and/or incisors and up to two additional teeth; Type II: involvement of first molars/incisors and several additional teeth; and Type III: generalized involvement (more than 14 teeth) but with bone loss notably more extensive on the first molars and/or incisors. Of the 182 patients, 129 (70.9%) were Type I; 43 (23.6%) were Type II, and 10 (5.5%) were Type III. The molars were involved more frequently than the incisors; more than one molar was always involved, with or without incisor involvement. Most cases had minimal or no radiographic caries, and 46% had demonstrable calculus. Of the remaining 88 cases from the 270 with the initial diagnosis of JP, 63 demonstrated severe bone loss on more than 14 teeth, with many of the teeth being involved to the same degree. These cases were termed rapidly progressive periodontitis. Six of the 88 cases had bone loss on only one tooth surface of the dentition. These cases were termed acute localized destruction of alveolar bone. The status of the other 19 cases could not be determined.  相似文献   

4.
We studied the periodontal disease progression and the relationship between some forms of destructive periodontitis in a group of Brazilian adolescents with high prevalence of periodontal destruction, and evaluated the adequacy of reducing data by limiting the measurement of disease to first molars and by aggregating and pooling site-scores into subject-level scores. Over a period of 3 years 222 adolescents were examined annually by bite-wing radiographs. Individuals displaying arc-shaped bone lesions adjacent to greater than or equal to 2 first molars were diagnosed as juvenile periodontitis (JP) patients, while those with greater than or equal to 1 first molars showing vertical lesions were regarded as periodontal risk subjects. Teenagers with greater than or equal to 2 first molars exhibiting longitudinal bone loss were defined as high-risk patients. At the ages of 13 and 16 years, 3 (1.3%) and 4 (1.8%) subjects had JP, while 12 (5.4%) and 28 (12.6%) were regarded as periodontal risks; 8 (3.6%) subjects were assigned to the high-risk group; 4 (1.8%) 13-year olds had greater than or equal to 1 first molars missing; hence, no loss of posterior teeth occurred over a period of 3 years. Analyzing the data at the site-level revealed progressive loss and little fluctuation in the alveolar bone height in the high-risk group, and a more pronounced bone loss at the mesial than at the distal surfaces. Simpler data sets were constructed by aggregating some of the site-scores or by pooling these into subject-level scores.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
The purpose of this study was to describe the changes in the molar relationship from the deciduous dentition to the permanent dentition in 121 subjects from the Iowa Longitudinal Growth Study. In addition, an attempt was made to determine the association between the various dentofacial variables and the changes in the molar relationship in 55 persons (33 male and 22 female subjects) with normal occlusion. All subjects were evaluated at three stages of dental development: stage I, completion of the deciduous dentition (means age = 4.94 years); stage II, when permanent first molars initially erupt into occlusion (means age = 6.91 years); and stage III, at the completion of eruption of the permanent dentition excluding third molars (means age = 13.01 years). The following sets of variables were evaluated: molar relationship, mesiodistal crown diameters of single and groups of deciduous and permanent teeth, dental arch widths, arch lengths, and various cephalometric dentofacial variables. Correlation coefficients and regression analyses were used to assess the relationships between these measurements and the changes in the molar relationship from the deciduous to the permanent dentition. The findings indicate that of the 242 sides evaluated in the deciduous dentition, 61.6% developed into a Class I molar relationship, 34.3% into Class II, and 4.1% into Class III. Those sides that started with a distal step in the deciduous dentition proceeded to develop into a Class II molar relationship in the permanent dentition. Of the sides with a flush terminal plane relationship in the deciduous dentition, 56% progressed to a Class I molar relationship and 44% to Class II in the permanent dentition. The presence of a mesial step in the deciduous dentition indicates a greater probability for a Class I molar relationship and a lesser probability for a Class II molar relationship. In the 55 subjects who achieved normal occlusion, the magnitude of change in the molar relationship was 1.91 mm in male subjects and 1.64 mm in female subjects. On the average, these cases had a mesial step in the deciduous dentition of 0.8 mm in male subjects and 1.0 mm in female subjects. There was a favorable difference between the maxillary and mandibular leeway spaces of 1.3 mm in male subjects and 1.1 mm in female subjects. There was also a favorable decrease in the Wits appraisal of 1.2 mm in male subjects and 0.6 mm in female subjects.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

6.
The need to accurately determine the prevalence of a disease is important especially in establishing treatment needs for particular population groups. Reported prevalences for juvenile periodontitis (JP) have varied from less than 0.1% to 17%. The use of overall prevalence values to determine treatment needs in populations which include various ethnic groups is not reliable since there is evidence that the prevalence in different groups is unequal. The purpose of this study was to determine the prevalence and sex ratio of JP in a large group of military recruits and to compare these values between the different racial populations. Thirty-eight cases of JP were diagnosed from a group of 5,013 young male and female recruits of varying ethnic origin. The overall prevalence was 0.76% and the female:male ratio 1.1:1.0. These findings raise questions as to the continued quotation of a female:male ratio of 3:1, and provide additional evidence for an overall ratio closer to 1:1. In addition, prevalences of JP varied considerably between racial groups. Blacks had a much higher JP prevalence (2.1%) than caucasians (0.09%). Black males had a higher prevalence (3.81%) than black females (1.99%). For black recruits the F:M ratio was 0.52:1. For caucasian recruits the F:M trend is opposite (4.3:1), although the number of cases diagnosed in the caucasian group was too low to compute a true ratio. The data support studies which show that in the blacks, the disease is less prevalent in females than in males. Caution must be exercised in interpreting results in any study in which the sample population is not categorized.  相似文献   

7.
OBJECTIVES: To investigate the prevalence of alveolar bone loss around the first permanent molars, and first and second deciduous molars in Australian school-aged children attending the Royal Dental Hospital of Melbourne. METHOD: Nine hundred and ninety-five records were examined for useable bitewing radiographs. From these, radiographs of 542 Australian school children aged 5-12 years were used. The cervical-enamel junction (CEJ) to the alveolar bone crest (ABC) distance was measured using the transparent ruler on the magnifier. Each inter-dental site that was readable was scored as one for the following categories: not available (NA); no bone loss (NBL)- the CEJ-ABC was < or =2 mm; questionable bone loss (QBL): the distance from the CEJ-ABC was >2 and <3 mm; and definite bone loss (DBL): the distance from the CEJ to ABC was > or =3 mm. RESULTS: Seventy-one children (13.0%) were found to have 83 DBL sites, as determined by bone levels >3.0 mm from the CEJ. Seventy children had QBL lesions only, 50 children had DBL only and 21 children had both. The overall prevalence of bone loss was 26%. Second deciduous molars were found to be the most affected teeth with almost 75% lesions being distal. These teeth comprised 50% of the DBL lesions. Children of Asian-Far Eastern origin had a higher percentage of sites with bone loss compared with children of Caucasian origin, being 29.5% and 19.7%, respectively, but lower than that of children of Middle-Eastern origin (35.2%). When the data were analysed with relation to age, there was no relationship between age and prevalence of bone loss. CONCLUSION: In the population studied, there was an overall prevalence of periodontal bone loss of 26% and DBL of 13% in an Australian school-aged group. Calculus was detected infrequently and, where present, was associated with bone loss.  相似文献   

8.
Over 80 per cent of the subjects showed some form of the character in the deciduous dentition, about 10 per cent having cusps; in the permanent dentition, about 70 per cent of the subjects had the character, 20 per cent showing cusps. Sexual dimorphism was not evident in the deciduous dentition but, in the permanent dentition, the character was more common in males who also showed a higher degree of expression than females. Generally, the trait occurred bilaterally with symmetrical expression in both dentitions. Although the character was present in the deciduous dentition but not the permanent in a number of subjects, the reverse situation was rare. Comparisons between siblings of individuals with the character and siblings of individuals from the general population provided some evidence of a genetic basis to the character, but its heritability is probably low. Variations in phenotypic trait expression between sides, sexes and dentitions probably reflect the interplay between environmental influences and the timing of developmental processes.  相似文献   

9.
Abstract 118 patients with juvenile periodontitis (JP), diagnosed when the patients were 13–19 years old, were studied retrospectively with respect to radio-graphic marginal bone loss in the primary dentition, experienced when the patients were 5–12 years old. 168 other 13–19 year old patients without any signs of bone Joss in the permanent teeth were used as a reference group. The JP patients were classified into 2 groups according to the number of sites with bone loss in the permanent dentition: JP group I having 1 site with bone loss (n=45) and JP group II having 2 sites with bone loss (n=73). It was found that 35 patients (52%) of JP group II displayed 1 or more sites with bone loss in the primary dentition during the age of 5–12 years. The corresponding numbers for JP group I and the reference group were 9 (20%) and 8 (5%) respectively. These findings indicate that juvenile periodontitis, at least in some individuals, may have its onset already in the primary dentition.  相似文献   

10.
OBJECTIVE: To evaluate the prevalence of enamel alterations affecting the deciduous and permanent central maxillary incisors of children with complete unilateral cleft lip and palate and to verify their characteristics. DESIGN: Cross-sectional. SETTING: Hospital for Rehabilitation of Craniofacial Anomalies-University of S?o Paulo, Bauru, S?o Paulo, Brazil. PATIENTS: A sample of 90 patients attending the Hospital for Rehabilitation of Craniofacial Anomalies, presenting with complete cleft lip and palate, of both genders, ages 2 to 11 years old. METHODOLOGY: The buccal surfaces of the maxillary central incisors of patients were analyzed for observation of the presence of enamel defects, their type, number, and location. The prevalence of defects was compared between deciduous and permanent teeth and between the incisors at the cleft and noncleft sides. RESULTS: There was a higher frequency of defects among incisors on the cleft side for both deciduous and permanent dentitions compared with the noncleft side (p < .05); the permanent central incisor was more frequently affected than the deciduous. Evaluation of the types of defects for both incisors in both dentitions demonstrated a homogeneous distribution, except for a lower proportion of yellow opacity in the permanent dentition on the cleft side. In general, the most affected area in all dentitions was the incisal third. CONCLUSION: The prevalence of enamel alterations affecting incisors adjacent to the cleft was higher than for incisors on the noncleft side. This difference also was present in the permanent dentition.  相似文献   

11.
Periodontal disease progression was studied on bitewing radiographs taken at baseline and after 1 year for a group of 422 teenagers who had no access to preventive or therapeutic dental services. Subjects exhibiting one or more proximal surfaces of 1st molars with longitudinal bone loss and/or with vertical bone defects at the 2nd examination were regarded as periodontal risk patients. This group then underwent a further examination in which periapical radiographs of the anterior teeth were taken and the clinical loss of attachment at the proximal surfaces of all teeth was assessed. Subsequently, the radiographic and clinical states of the risk group were compared. Most sites exhibiting bone loss during the study period displayed vertical bone defects and were largely confined to mesial surfaces of first molars. 24% of sites showing alveolar bone loss at baseline demonstrated further loss 1 year later. Girls exhibited significantly higher prevalence and incidence of sites showing bone loss than did boys. 24 children (5.7%) were regarded as periodontal risk patients. The radiographs significantly underestimated the prevalence of periodontal destruction in the risk group as compared to clinical measurements. It was concluded that using 2 bitewing radiographs is adequate for the identification of risk subjects, and that periodontal progression in adolescence occurs mainly in the first molar region and may affect girls more often than boys.  相似文献   

12.
Hypophosphatasia is an inherited disorder characterized by defective bone mineralization, deficiency of alkaline phosphatase (ALP) activity, increased excretion of phosphoethanolamine (PEA) in the urine and premature loss of the deciduous teeth. A male hypophosphatasia patient aged 15 years 6 months, with premature exfoliation of the deciduous teeth and manifesting severe periodontal destruction in the permanent dentition, was examined. Antibody titers against seven strains by the enzyme-linked immunosorbent assay (ELISA), monocyte and neutrophil chemotaxis studies and cellular immunity tests were performed. Low levels of ALP in serum and PEA in the urine were found. Radiographic examination showed a similar pattern of alveolar bone loss to that of the localized juvenile periodontitis. Suppressed monocyte and neutrophil chemotaxis were not detected. Slightly depressed CD2+, CD3+ and CD4+ and slightly elevated activity of NK cells were found. An elevated level of antibody to Porphyromonas gingivalis was observed and this antibody titer was decreased by periodontal treatments. The affected sites of the patient showed resistance to conventional periodontal therapy. P. gingivalis was estimated to associate as an important pathogen in the etiology of periodontal destruction in this hypophosphatasia patient in addition to the dental abnormalities such as abnormal enamel, dentin, or cementum formation.  相似文献   

13.
The present radiographic and clinical survey was performed to study the prevalence of "incipient juvenile periodontitis" in a population of 16-year old adolescents in Switzerland. The subjects to be screened were selected on the basis of the population distribution in the year 1980 in the territory of Switzerland. 7% of all 16-year old adolescents proportionally distributed into the different ethnic groups of Switzerland were incorporated in the study. From the school dental systems, a total of 7604 pairs of bite-wing radiographs were obtained and evaluated for fillings and iatrogenic factors, gross amounts of calculus, resorption of alveolar bone. A diagnosis of "incipient juveline periodontitis" was given if the clinical criteria of this disorder proposed by Baer were met. In 7142 pairs of bite-wing radiographs, such a diagnosis was attributed to 7 female and 12 male patients. Subsequently, they were asked if they would be examined at the University of Berne School of Dental Medicine. On the basis of history, a complete periodontal chart and full mouth radiographs, the diagnosis was confirmed or refuted. 8 patients (4 female and 4 male) were definitely diagnosed as "incipient juvenile periodontitis". This resulted in a prevalence of 0.1% with a ratio of female to male of 1:1 in the country of Switzerland at age 16. As in other industrialized countries, this prevalence seems not to be a major public health problem.  相似文献   

14.
Aim: To look for clinical signs of periodontal disease in young adults who exhibited radiographic bone loss and detectable numbers of Aggregatibacter actinomycetemcomitans in their primary dentition.
Material and methods: Periodontal status and radiographic bone loss were examined in each of the subjects 16 years after the baseline observations. Techniques for anaerobic and selective culture, and checkerboard, were used to detect periodontitis-associated bacterial species. The isolated A. actinomycetemcomitans strains were characterized by polymerase chain reaction.
Results: Signs of localized attachment loss were found in three out of the 13 examined subjects. A. actinomycetemcomitans was recovered from six of these subjects and two of these samples were from sites with deepened probing depths and attachment loss. Among the isolated A. actinomycetemcomitans strains, serotypes a–c and e, but not d or f, were found. None of the isolated strains belonged to the highly leucotoxic JP2 clone, and one strain lacked genes for the cytolethal distending toxin.
Conclusions: This study indicates that the presence of A. actinomycetemcomitans and early bone loss in the primary dentition does not necessarily predispose the individual to periodontal attachment loss in the permanent dentition.  相似文献   

15.
AIM: The purpose of this report is to present two cases of totally impacted maxillary deciduous molars, considered a rarity in dental practice. BACKGROUND: Primary tooth impaction is quite rare during the development of primary dentition. Various factors contribute to the impaction of a deciduous tooth, including anklyosis, congenitally missing permanent teeth, defects in the periodontal membrane, trauma, injury of the periodontal ligament, precocious eruption of the first permanent molar, defective eruptive force, or a combination of these factors. REPORTS: Case #1: An 18-year-old male presented with a complaint of spontaneous repetitious pain in the maxillary right premolar region. The maxillary right second premolar was clinically absent. Panoramic and periapical radiographs revealed an impacted second premolar close to the inferior wall of the maxillary sinus and an impacted deciduous molar deeply embedded in bone within the maxillary sinus. Case #2: A 14-year-old girl presented with a complaint of crowding of the maxillary teeth. The maxillary right second premolar and the maxillary permanent canines were clinically absent. A panoramic radiograph revealed an impacted maxillary right second premolar and an impacted deciduous molar embedded within bone close to the inferior wall of the maxillary sinus. SUMMARY: The total impactation of deciduous teeth is a rare condition, and few cases have been reported in the literature. The condition generally affects the mandibular second deciduous molar and the maxillary first deciduous least often. In this paper, two cases of totally impacted maxillary deciduous molars are reported.  相似文献   

16.
Objective:  To determine the prevalence of oral pathologic findings in an ancient culture that inhabited the Atacama Desert.
Materials and methods:  A systematic examination was performed on the remains of 83 individuals unearthed from a prehistoric burial ground. A total of 57 skeletal remains achieved appropriate inclusion criteria, from which estimated age at death, gender, ante- and postmortem tooth loss, prevalence and location of caries, apical periodontitis sequela, alveolar bone resorption and attrition were recorded.
Results:  From the analyzed skeletal remains (13 male, 22 female and 22 not identifiable), the mean age estimated was 29.9 ± 13.8 years. A total of 89.4% of them presented permanent dentition with a mean ante-mortem tooth loss of 9.0 teeth and a postmortem mean tooth loss of 14.4 teeth per subject. In all, 46.4% of the postmortem remaining permanent teeth ( n  = 237) showed caries lesions. Interproximal caries was most frequently observed (31.5%), followed by occlusal (25.9%) and cervical caries (19.4%). Root remnants were found in 23.1% of the cases. In addition, 58.0% of the adults presented attrition, 26.0% signs of apical periodontitis and 44.0% loss of alveolar bone support >5 mm.
Conclusion:  The remains of jaws and teeth of the individuals examined in this study presented sequelae of severe oral health damage due to caries and periodontal disease.  相似文献   

17.
Papillon-Lefévre syndrome (PLS) is characterized by severe periodontal disease extending to destruction of the alveolar bone surrounding deciduous teeth and palmoplantar hyperkeratosis of the skin. Increased susceptibility to infection has been reported among individuals with the cathepsin C (CTSC) gene mutation. This article reports a 7-year-old Japanese girl who presented with deciduous tooth mobility and was diagnosed as having PLS. Radiographic examination revealed loosening of deciduous incisors and the right second molar of the maxilla, and destruction of the alveolar bone around the residual deciduous dentition. However, there was no destruction of the alveolar bone around the permanent molars. The patient did not show the typical signs of CTSC polymorphism, which almost always negatively impacts certain activating enzymes. With respect to immune function, analysis of the patient's leukocytes indicated that H(2)O(2), chemotactic and phagocytotic functions were within the normal range. However, the special precautions normally applied to prevent infections in PLS patients undergoing dental treatment were taken.  相似文献   

18.
The aim of this epidemiological survey was to analyze the periodontal conditions of 19-year old individuals in an urban area of Sweden, with special reference to gender and socioeconomic factors. A randomized sample of 272 individuals living in G?teborg, Sweden, was clinically examined with regard to oral hygiene, gingivitis, periodontal pockets, probing attachment loss (PAL) and gingival recession. Bitewing radiographs were used for assessments of alveolar bone level (ABL) and dental calculus. A questionnaire-based interview regarding oral hygiene habits was included. Data were analyzed with regard to differences between gender and socioeconomic grouping. The subjects showed a mean plaque score of 59% and a gingivitis score of 44%. 70% of the adolescents had a plaque score of > or = 50%, whereas corresponding figure for gingivitis was 37%. 27% of the subjects had at least one tooth with gingival recession. The mean prevalence of sites with probing depth of > or = 6 mm was 0.5, and the prevalence of PAL > or = 2 mm was 0.7. A radiographic bone level of > or = 2 mm was observed at on average 0.8 teeth per subject. Females had significantly less plaque and gingivitis than males and significantly higher number of teeth with gingival recession. There were no clinically significant differences in periodontal conditions between socioeconomic groups. In conclusion,the survey revealed higher prevalence of plaque and gingivitis among male than female adolescents but no differences between socioeconomic groups.  相似文献   

19.
BACKGROUND: Papillon-Lefèvre syndrome (PLS) is an autosomal recessive disease characterized by hyperkeratosis of the palms and soles combined with premature loss of the primary and permanent dentition. Several treatment regimens have been recommended in the literature; however, a definitive treatment protocol has not been established. This case report evaluates the success of combined therapy in managing a patient with PLS. METHODS: A 6-year-old girl diagnosed with PLS presented with aggressive periodontal destruction of her primary and permanent dentitions. After extraction of periodontally affected teeth, the edentate region was rehabilitated with different temporary dentures until her skeletal growth was complete. At the same time, her orthodontic treatment was performed. The early loss of her incisors resulted in inadequate alveolar bone height and width for esthetic-advanced prosthetic rehabilitation. Alveolar bone augmentation was performed, and 6 months later, two intraosseous dental implants were placed into the central incisor zone. RESULTS: After 13 years of treatment and follow-up, the patient had periodontally healthy permanent dentition. She had practiced meticulous oral hygiene, and the orthodontic treatment was successful and without incident. Alveolar ridge augmentation and placement of an intraosseous implant with guided bone regeneration were performed successfully. CONCLUSIONS: This case report demonstrates that individually developed treatment protocols can provide long-term dental/periodontal success in patients with PLS. A multidisciplinary approach with advanced periodontal surgery, orthodontic and prosthetic treatment, and implant therapy may be an appropriate treatment modality for dental rehabilitation in patients with PLS.  相似文献   

20.
Periodontal status in relation to age and tooth type   总被引:2,自引:0,他引:2  
The purpose of the present study was to assess by radiographic means the pattern of destructive periodontal disease within the dentition of individuals of different ages. Full-mouth series of intra-oral radiographs from 531 dentate individuals aged 25-75 years were examined with respect to number and type of remaining teeth, location of the alveolar bone in relation to the cemento-enamel junction and presence of angular bony defects. The assessments of alveolar bone levels and angular bony defects were performed at the approximal surfaces of all teeth present. The results showed that although most individuals had experienced a reduction in alveolar bone height with age, only a small number of subjects had developed advanced breakdown of the periodontium. Hence, pronounced bone loss was observed in only 11% of the subjects and was non-existent in ages below 35 years. 23% of the individuals accounted for 3/4 of the total number of sites with bone level values (bone loss) of greater than or equal to 6 mm. Out of the total number of tooth sites examined, 28% showed no bone loss, while 13% demonstrated pronounced periodontal tissue breakdown. Angular bony defects were found at 8% of all teeth examined and were most frequent at the maxillary first premolars. Teeth in the incisor regions consistently showed the highest frequency of advanced alveolar bone loss and the lowest frequency of normal tissue support, while corresponding figures for teeth in the molar regions were found to be the opposite. However, molars were the most frequently missing teeth.  相似文献   

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