13例老年人髓室底穿通患牙治疗的临床报告

目的:探讨老年人髓室底穿通患牙的治疗效果.方法:对13例老年人髓室底穿通的病人进行临床分析,探讨临床治疗方法.结果:13例髓室底穿通患牙中,经平均2年随诊观察,3例拔除,10例使用良好.结论:老年人髓室底穿通患牙也可通过治疗保留,以恢复咀嚼功能.     

Age‐related changes in mastication

The paper reviews human mastication, focusing on its age‐related changes. The first part describes mastication adaptation in young healthy individuals. Adaptation to obtain a food bolus ready to be swallowed relies on variations in number of cycles, muscle strength and volume of emitted saliva. As a result, the food bolus displays granulometric and rheological properties, the values of which are maintained within the adaptive range of deglutition. The second part concerns healthy ageing. Some mastication parameters are slightly modified by age, but ageing itself does not impair mastication, as the adaptation possibilities remain operant. The third part reports on very aged subjects, who display frequent systemic or local diseases. Local and/or general diseases such as tooth loss, salivary defect, or motor impairment are then indistinguishably superimposed on the effects of very old age. The resulting impaired function increases the risk of aspiration and choking. Lastly, the consequences for eating behaviour and nutrition are evoked.     

Evaluation of sensitivity of teeth after mandibular fractures

The sensitivity of teeth anterior to a fracture between the mental and mandibular foramina has been tested and followed up until reinnervation or 3 years has passed. This study assessed the reinnervation period, the number of denervated teeth, and their clinical importance. Fifty patients and 459 teeth were examined. Two hundred and seventy-three teeth were affected and had potentially impaired innervation. Tests after injury showed non-responsive teeth in 81% of affected teeth. Six weeks after injury, 19% of teeth were reinnervated; by 1 year after injury, 92% of initially non-responsive teeth were reinnervated. Most teeth (34%) were reinnervated from 6 weeks to 3 months. All 23/186 initially non-responsive, unaffected, contralateral corresponding teeth were reinnervated within 6 weeks. A year after injury, 95% of incisors, 91% of canines, 94% of premolars, and 82% of molars were reinnervated. Three years after injury, 8% of teeth remain denervated. During the second and third years, no reinnervation occurred, but clinical signs of pulp devitalisation of denervated teeth occurred in 18% or 1% of the initially non-responsive affected teeth. The results revealed the stability of pulp 1 year after injury. Denervated teeth should not be treated if no clinical or radiological signs of devitalisation exist.     

Pulp calcifications in traumatized primary incisors A morphological and inductive analysis study

The purpose of this study was to investigate histopathological changes in primary teeth following trauma, and to look for possible correlations between the morphology of pulpal calcification and clinical findings. The material consisted of 123 primary teeth from 98 Danish children aged 9–108 months (mean age 33.5 ± 19.7 months) at the time of injury. The specimens were analyzed by means of light and scanning and transmission electron microscopy. Data from the clinical investigation and from predetermined ranked parameters from the histological analysis were processed in a computerized inductive analysis program. The results, describing patterns of co-variation, are presented as a decision tree. The most common diagnosis was intrusion luxation (54%). In 41% of all teeth, the degree of obliteration was less than 1/4 of the pulpal lumen. In most cases (79%), no denticles were visible. When present, 80% of the denticles had a bone-like appearance. Tissues occluding the pulpal lumen were either dentin-like (49%). bone-like (19%), or fibrotic (9%). It could be concluded that these varying responses could not be correlated with explicit clinical diagnoses. However, in certain combinations, histological parameters could be correlated to clinical findings.     

Radiological evaluation of the morphological changes of root canals shaped with ProTaper™ for hand use and the ProTaper™ and RaCe™ rotary instruments

This study evaluated, by means of the radiography examination, the occurrence of deviations in the apical third of root canals shaped with hand and rotary instruments. Sixty mandibular human molars were divided into three groups. The root canals in group 1 were instrumented with ProTaper? (Dentsply/Maillefer, Ballaigues, Switzerland) for hand use, group 2 with ProTaper? and group 3 with RaCe?. The images obtained by double superimposition of the pre‐ and postoperative radiographs were evaluated by two endodontists with the aid of a magnifier‐viewer and a fivefold magnifier. Statistical analysis was performed using the Fisher‐Freeman‐Halton. The instrumentation using the ProTaper? for hand use showed 25% of the canals with a deviation in the apical third, as did the ProTaper?, while the corresponding figure for the RaCe? (FKG Dentaire, La‐Chaux‐de‐Fonds, Switzerland) was 20%, but these results were not statistically significant. There was no correlation between the occurrence of deviations in the apical third and the systems used.     

Influence of the mineral content and morphological pattern of artificial root caries lesion on composite resin bond strength

Dentine substrates with different mineral contents and morphological patterns were created by submitting root slabs to the following treatments: (A) immersion in artificial saliva during the experimental period (control), (B) demineralization for 32 h to induce caries lesion (demineralized group), and (C) demineralization for 32 h followed by remineralization for 8 d (remineralized group). The slabs were longitudinally sectioned, the mineral content was determined by cross-sectional microhardness, and the bond strength of an adhesive system/composite resin was assessed using a microtensile bond strength test. The dentine morphology after the treatments as well as the failure pattern of the debonded specimens was examined by scanning electron microscopy. Statistically significant differences were found in mineral content. Morphological analysis showed marked differences between the patterns of demineralized and remineralized substrates. The bond strength mean value of the control A did not differ from the group B, but was statistically higher than the group C. Since no linear relationship was found between dentine mineral content and bond strength values, it could be suggested that the morphological pattern may be more relevant than the mineral content to explain the bond strength of composite resin to dentine.     

Effect of luxation injuries on permanent teeth

Abstract Trauma to the supporting tissues of the teeth are among the most common dental injuries, leading to such complications as pulp canal obliteration, necrosis and root resorption. The aim of this investigation was to study the outcome for young permanent teeth subjected to luxation injuries. From 108 dental records 171 teeth with injuries to the supporting tissue were selected. The material comprised 130 subluxated, 15 extruded, 9 intruded, 15 exarticulated and 6 laterally luxated teeth in children aged 6–19 years. Apart from luxation, 59 teeth (35%) had additional crown and root fractures. 65% of the teeth recovered without complications. 78% of the subluxated teeth and 24% of the luxated teeth showed uneventful posttraumatic healing. Concomitant uncomplicated crown fractures or root fractures without displacement of the coronal fragment did not interfere with the healing. Of 60 teeth with healing complications, 52 (87%) were subsequently recorded as healed, the remaining 8 were extracted or had progressive root resorption. Loss of pulp vitality and external root resorptions were the most often recorded complications (28% and 17% of the total material respectively). Pulp canal obliteration was noted in 3% of the cases. Extent of injury and degree of tooth maturity were found to be related to healing compliations.     

Adjustment of the M-component of the DMFS index for prevalence studies of older adults

Abstract Cross-sectional studies of caries in older adults report a substantial number of missing teeth, making it difficult to estimate caries experience accurately. The goal of this study was to improve the method of estimating caries experience as expressed by the DMFS index in population groups with missing teeth. The adjustment was demonstrated with reference to the Piedmont 65+ Dental Study conducted on a random sample of 363 community-dwelling older adults in North Carolina who were followed for 5 years. These older dentate adults had a mean (±SE) of 11.7±0.5 teeth missing at baseline, 56.1±2.5 missing surfaces and a DMFS of 86.7±2.0. A predicted caries prevalence was determined from the DFS at 5 yrs plus the 5-yr DFS incidence and the baseline DFS of teeth lost during the study period. Then a formula was developed that would estimate the predicted caries prevalence as a function of the observed 5-yr DMFS. This formula provided a good estimation of caries prevalence at 5 yrs (DMFS_adj) when compared with the predicted prevalence (paired t-test, p>0.05), while prevalence was underestimated by the DFS and greatly overestimated by the traditional DMFS index. Subgroup analyses by race, sex. and periodontal status also indicated that the DMFS_adj resulted in patterns of estimates similar to the predicted prevalence, while the DFS and the DMFS were likely to result in different findings. The DMFS from the time of tooth eruption also was adjusted using this formula. The resulting analyses of subgroup differences in caries were not different from the previous estimates based on the 5-yr historical data, indicating that the adjustment of all M surfaces avoids the biases inherent in the traditional DMFS and DFS indices. This study showed that predicted caries prevalence could be estimated by adjusting the M component of the DMFS. It appears that this adjustment formula can be used without obvious bias, but additional studies are needed to provide adjustment figures for populations with different caries prevalences.     

Prevalence and interrelationships of root surface caries in Lufa, Papua New Guinea

abstract This survey of 222 adults aged 18 years and over, in highland communities near Lufa, Papua New Guinea, has revealed that: (1) the prevalence of root caries is much higher than that of coronal caries in persons aged 30 to 39 years; (2) periodontal disease and root caries are statistically strongly associated. These findings confirm one of the study hypotheses that, under certain combinations of etiologic and environmental influences, the prevalence of root caries may equal or exceed the prevalence of coronal caries, and furthermore, they strongly support the other study hypothesis that certain dietobacterial plaque infections are not conducive to highly active coronal lesions but are associated with periodontal lesions and radicular cavitation.     

Clinical outcomes for permanent incisor luxations in a pediatric population. III. Lateral luxations

Abstract –  A longitudinal outcome study was designed to identify variables that influenced tooth survival as well as pulpal and periodontal outcomes of laterally luxated permanent maxillary incisors of children and adolescents. All cases were treated between June 1988 and June 1998 in a teaching hospital clinic. Clinical and radiographic data were collected for 42 patients (26 males, 16 females) that represented 58 permanent maxillary incisors. Mean age at the time of injury was 11.4 years (range: 6.3–17.8 years). Mean follow-up time was 1460 days (range: 183–3905 days). In the entire sample ( n  = 58), no incisors required extraction. Survival analysis and logistic regression were used to identify variables significantly related to the survival and healing outcomes of these incisors. Pulp necrosis (PN) (40%) and pulp canal obliteration (PCO) (40%) were common healing complications. Proportional hazards (Cox) regression showed that PN develops within the first year. Logistic regression demonstrated that root development ( P  = 0.3, PN; P  = 0.8, PCO) and extent of lateral luxation ( P  = 0.5, PN; P  = 0.9, PCO) were not significantly related to PN and PCO. This study provides the first report of incisor survival in children and adolescents following lateral luxation injuries.     

Treatment preferences of deep carious lesions in mature teeth: Questionnaire study among dentists in Northern Norway

Abstract

Objective. To investigate preferred treatment methods of deep carious lesions in mature permanent teeth among dentists in Northern Norway. Materials and methods. The survey included all 437 general dental practitioners in Northern Norway working in the private or the public dental health service. The participants received an invitation with a radiograph and a clinical picture of a deep carious lesion in a mature permanent tooth and a questionnaire asking about demographic characteristics and their preferred treatment methods related to different clinical deep caries diagnoses. Results. The response rate was 56%. There was an over-representation of publicly employed dentists among the respondents; otherwise no systematic bias related to non-responders was detected. In the absence of carious exposure and no symptoms, total caries excavation was the preferred treatment method (49%) followed by stepwise excavation (45%). In cases of deep caries and no exposure with symptoms, the preferences were equally distributed between root canal treatment (39%) and stepwise excavation (38%). In the presence of carious exposure but no symptoms, the preferred treatment method was direct pulp capping (51%) and in carious exposure with symptoms root canal treatment was the preferred treatment method (91%). Conclusions. There is no uniform treatment method of deep carious lesions among dentists in Northern Norway.     

Descriptors of permanent teeth with cariously exposed pulp in patients presenting at a Nigerian hospital

Abstract

Aim. To describe the pattern of presentation of carious permanent teeth with pulp exposure and to determine factors associated with choice of treatment for such teeth. Materials and methods. All patients presenting at the oral diagnosis clinic of Lagos University Teaching Hospital Dental centre between January 2009 and June 2009 were examined and those with carious lesion involving the pulp were included in the study. The history and character of pain from teeth, extent of tooth structure lost, proposed treatment and reason for proposed treatment was recorded. Results. The tooth most affected by pulp exposure due to caries is the lower first molar (17.5%). Extraction was the treatment of choice for many patients due to the following reasons: obliterated root canals (30%), patients' preference (30%) and non-restorable teeth (22%). Conclusion. Extraction was the predominant treatment chosen for cariously exposed permanent teeth due to the condition of the tooth.     

Partial pulpotomy in young permanent teeth with deep carious lesions

Abstract The material comprised 37 young posterior teeth with deep carious lesions and exposed pulps, treated with partial pulpotomy and dressed with calcium hydroxide. The teeth were divided into two groups. Group 1 consisted of 31 teeth with no clinical or radiographic symptoms before treatment, Group 2 of 6 teeth with temporary pain, widened periodontal space periapically and/or productive osteitis, i.e. increased density of the surrounding alveolar bone. After an observation time of 24 to 140 months (x?= 56 months), healing had occurred in 29 of 31 teeth in Group 1 (93.5%) and in 4 of 6 teeth in Group 2. It was concluded that the present, as well as previously reported results indicate that partial pulpotomy may be an adequate treatment for young permanent molars with a carious exposure, although more studies are needed before the treatment can be recommended for routine clinical use.     

Age‐related changes in elastic properties and moisture content of lower labial mucosa

Summary The purpose of this study was to clarify age‐related changes in the elastic properties and moisture content of the lower labial mucosa. Elastic properties and moisture content were also compared between the lower labial mucosa and skin. A total of 85 adults aged 20–82 took part in the study. Elastic properties (distensibility and elasticity) and moisture content of lower labial mucosa and skin were determined in each participant. Measurements for the oral mucosa were taken at the midline of the lower labial mucosa; for the skin, they were taken at the midpoint of the right anterior surface of the forearm. Pearson’s correlation coefficient and the Mann–Whitney U test were used for the statistical analysis. A stepwise multiple linear regression analysis was also performed, with age as the dependent variable and sex, distensibility, elasticity and moisture content of the lower labial mucosa as independent variables. A negative correlation was found between age and distensibility of the lower labial mucosa. No correlation was observed between age and elasticity of the lower labial mucosa. A negative correlation was observed between age and moisture content of the lower labial mucosa. A significant difference was observed in moisture content between the 20‐ to 39‐year‐old group and the over 40‐year‐old group. Stepwise analysis indentified distensibility and moisture content of the lower labial mucosa as predictive factors of age. The results indicate that distensibility and moisture content of the lower labial mucosa decrease with age. Moisture content in the over 40‐year‐old group, in particular, was lower than in the 20‐ to –30‐year‐old group.     

Tooth and root conditions in the middle-aged and the elderly in Hong Kong

Abstract In an oral health survey of Hong Kong Chinese conducted in 1991, a sample of 372 35–44-yr-olds and 537 noninstitutionalized 65–74-yr-olds were interviewed and clinically examined. The examination procedures, instruments, and diagnostic criteria used to detect coronal caries followed those recommended by the World Health Organization (1987). The diagnostic criteria used to assess root-surface caries were based on those used in a national oral health survey of US employed adults (National Institute of Denial Research. 1987). Calibration of examiners was conducted before the survey and the interexaminer reliability was found to be very high; the kappa statistics were 0.93 and 0.91 for the younger and older age groups, respectively. None of the 35–44-yr-olds were edentulous and 96% had 21 teeth or more. The prevalence of edentulousness among the elderly was 12%. The DMFT indices of the younger and older age groups were 8.7 and 18.9, respectively. In both age groups, MT was the major component of the DMFT index, and female subjects had a slightly higher score. The prevalences of decayed/filled roots were 7% and 26%i for the 35–44- and 65–74-yr-olds, respectively. As compared with previous surveys conducted in Hong Kong, there has been a 40% reduction in the DMFT index of the 35–44-yr-olds since 1968, but little change in the tooth and root conditions was noted between 1984 and 1991.     

深龋基牙固定修复后发生牙髓病变的危险性分析

目的：探讨深龋基牙固定修复后发生牙髓病变的危险性。方法：选择2002年1月至2004年12月,在口腔中心就诊患深龋且治疗成功又作为固定冠、桥修复基牙的患者510例,男272例,女238例,年龄19-72岁。将这些患者中的深龋基牙542颗作为深龋组;正常牙体基牙312颗为对照组。观察2组基牙固定冠桥修复后牙髓状况,深龋组进一步分析牙髓病变与牙位的关系。421例患者661颗基牙成功回访。结果：2年内深龋组397颗基牙中41颗出现牙髓病变,发生率10．33％;对照组264颗基牙3颗出现牙髓病变,发生率1．14％,2组间有显著的统计学差异。发生牙髓病变多在修复后的半年内。深龋下颌前牙牙髓病变率23．08％;下颌双尖牙牙髓病变率17．31％。结论：深龋基牙固定修复后发生牙髓病变的危险性显著高于牙体正常牙。固定修复尤其对患深龋的下颌前牙、下颌双尖牙牙髓健康影响较大,临床在选做冠桥修复的基牙时应谨慎。     

Pulpal blood flow in immature permanent dog teeth after replantation

Abstract – Pulpal blood flow (PBF) was measured by H₂-gas clearance in 35 replanted (incisors and premolars) and 22 contralateral control dog teeth. The PBF measurements were taken 6, 10, 16, 21 and 28 days after replantation. At 6, 10 and 16 days after replantation there was no measurable blood flow in the coronal pulp of either replanted incisors or premolars. 21 days after replantation a considerable reduction in PBF was measured in all replanted teeth. On average, PBF was reduced to about one fifth of PBF in the simultaneously measured contralateral controls. Four weeks after replantation, a more than threefold increase in PBF was measured in premolars with two roots, while PBF in premolars with one root and incisors was consistently reduced to an average of 40% of the controls. The vascular pattern of the teeth 4 wk after replantation was identified with perfusion of silicon rubber. The measurements suggest that replanted multirooted teeth revascularize more easily than single-rooted teeth, and that pulpal repair is restored by a gradual replacement and proliferation of new tissue.