Results of treatment of cancer of the lip

A study was carried out in Sancti Spiritus Province in the 1984-1986 period about the results of the treatment of lip cancer. Male patients were the most affected by lip cancer (CIE 8-140) in our series. The place of the tumor was predominantly the lower lip (p less than or equal to 0.001). Surgical treatment was used in 96.8% of the cases and the cuneiform (wedge-shaped) exeresis was the most commonly used method in the early stages of the disease (T1 y T2). Casta?ón keloplasty was the reconstructive procedure used in 18.7% of the patients. Local sepsis was present in 31.2% of the patients undergoing surgery, occurring most frequently in upper lip tumors.     

口底癌34例临床分析

目的探讨口底癌的临床特性、治疗方法及预后。方法对我院自1992—2002年住院治疗的34例口底癌患者进行回顾性分析。结果34例口底癌患者中,男28例(82.4%),女6例(17.6%),男女比为4.7∶1,平均发病年龄58岁。发病部位:前口底22例(64.7%),后口底12例(35.3%)。淋巴结转移率41.2%。单纯手术组、化疗加手术组、放疗加手术组、化疗加手术加放疗组的5年生存率分别为45.5%、60.0%、50.0%、62.5%。结论口底癌以中老年患者好发,男性居多。易发生淋巴结转移,综合疗法疗效较好。     

Evidence of the validity of a model of determinants of quality of restorative dental care

A model describing the relationship between self-reported quality of restorative dentistry and dentist characteristics for 119 Montana general dentists is presented. The best predictors formed a significant model explaining 22% of the variance of the quality measure. Results are contrasted with a previous estimation of the model for 102 Washington general practitioners. Evidence for the external validity of the model is presented.     

平阳霉素对血管内皮细胞急性损伤后酶活性变化的实验研究

目的：探讨平阳霉素损伤血管内皮细胞的机制,为临床应用提供组织学依据。方法：选用成年Wistar大白鼠42只（其中6只为正常对照）,经肠系膜静脉分别注入平骒霉素（24只）或鱼肝油酸钠（12只）后,分别于注药后0．5,1,2,4,8,24h,切取肝脏组织,通过酶组化染色法测定肝窦内皮细胞的5’－核苷酸酶,肝细胞的琥珀酸脱氢酶（SDH）及乳酸脱氢酶（LDH）活性,结果：注入药液后,肝窦内皮细胞的5’－核苷酸酶,肝细胞的SDH和LDH活性随时间逐渐下降,其中平阳霉素组下降较轻微,结论：平阳霉素和鱼肝油酸钠都可对血管内皮细胞产生损伤,损伤的性质一样,均为非特异性,但平阳霉素损伤程度轻微,而鱼肝油酸钠严重。     

Design of clinical trials of traditional therapies of periodontitis

The present paper on the design of clinical trials of periodontal therapy first addresses the issue of the etiology of periodontal disease. It is suggested that most if not all forms of destructive periodontal disease are caused by microorganisms and that there are different forms of disease with different microbial etiologies. The progressive nature of destructive periodontal disease is subsequently discussed and it is emphasized that, in a given patient, periodontal sites which show signs of inflammation and attachment loss may not over a period of several months and years show further sign of attachment loss. The present methods of assessing periodontal disease do not allow us to discriminate between potentially active and inactive sites in untreated patients. The significance and variability of indicators of periodontal disease such as bleeding on probing, probing pocket depth and probing attachment level measurements are discussed. The errors inherent in the various measurements are analyzed and suggestions are presented describing how alterations in any of the above parameters could be identified and presented in a clinical trial. Of concern for the statistical analysis of clinical data of periodontal disease is the definition of the "experimental unit". For a number of years, the "experimental unit" in periodontal trials was the patient. It is clear, however, that different sites within the same individual show different patterns of disease progression and lesion morphology and often respond differently to periodontal therapy. Statistical analyses must consequently be designed which recognize differences in site-to-site infection and lesion morphology within a common host. Until such analyses are available, the investigator should be wary of pooling data within the same individual, since such pooling may obscure meaningful alternatives which may take place in individual periodontal sites. Some goals of periodontal therapy are subsequently identified. 4 goals are discussed more in detail, namely: to establish conditions which will allow the patient to maintain a dentition without further breakdown of the periodontium; to reduce pocket depth to establish an anatomy in the dentogingival region which with proper maintainance care will prevent the re-establishment of the subgingival infection; to gain attachment as a result of treatment; to assess the effect of a certain chemotherapeutic agent on periodontal disease.     

Comparative analysis of results of mathematical simulation of stressed deformed status of pin dentures of different design

A computer study of 99 types of mathematical models of teeth armed with stump pin insertions widely used in dentistry (group 1--anchor pins and group 2--cast pin insertions suggested by the authors). Tooth models differed by shape, size, and properties of the design material. The shape and parameters of stump pin insertion were proven to be more significant than the properties of design material. The choice of pin design is determined by the clinical situation, topography and anatomy of tooth crown destruction, and maxillodental disease.     

Experimental evidence of formation of imines in the course of reduction of hydrazones

The reduction of hydrazones is generally suggested to proceed through a reductive cleavage of the nitrogen–nitrogen bond followed by a reduction of the carbon–nitrogen bond. This sequence of reduction processes is here supported for fluorenone (V) and benzophenone (VI) hydrazones as well as by a comparison of the reduction of fluorenone and benzophenone hydrazonium ions (I,III) with corresponding imines (II,IV). Another proof of the presence of imines as intermediates is the splitting of four-electron waves of hydrazones V and VI and hydrazonium ions I and VIII into two waves at pH < 2. This has been interpreted as due to differences in slopes dE_1/2/dpH and pK_a-values of protonated hydrazine derivatives on one side and corresponding imines on the other. In this pH-range imines formed in reductions of VI and VIII are reduced in a single two-electron wave, those of I and V in two one-electron steps. Fluorenone imine (II) is sufficiently stable to allow recording of time-independent current–voltage curves between pH 6 and 11. In this pH-range the imine (II) is reduced in two one-electron steps. Benzophenone imine (IV) has been found stable between pH 4.6 and 12. At pH 4.6–8 the reduction of the imine IV takes place in a single two-electron step, at pH 8–12 in two one-electron steps. Final proof of the initial cleavage of the N–N bond is presented by comparison with the reduction of nitrones.     

A comparison of four modes of evaluating depth of cure of light-activated composites

Four commonly used methods for evaluating depth of cure in light-activated composites were compared. Optical and scraping methods correlate well, but severely overestimate depth of cure as compared with hardness testing or degree of conversion analysis. Degree of conversion appears to be the most sensitive test of depth of cure.     

Electrodeposition of bilayers of dithiols

We report an electrochemical method to form a bilayer of dithiol. The cyclic voltammogram of the oxidative deposition of an aromatic dithiol on gold from an alkaline aqueous solution reveals two current peaks separated by more than 400 mV. The integrated charge of the oxidative current peak (B) at the most positive potential is twice that of the other oxidative current peak (A). These two oxidative current peaks were characterized by differential capacitance and electrochemical quartz crystal microbalance (EQCM) measurements. A decrease of the capacity by a factor of two, and an increase of the EQCM frequency change by a factor of two were observed when the potential was scanned from a value where only the first oxidative peak (A) is obtained, to a potential where both oxidative current peaks (A and B) are obtained. Infrared spectra show that the aromatic dithiols adsorb vertically at potentials corresponding to the current peak A and they become tilted for potentials corresponding to the current peak B. The simple relationships between the properties of the two oxidative current peaks are found to be compatible with a step-wise oxidative deposition of a bilayer of dithiol.     

舌前腺囊肿的治疗总结

目的：比较2种手术方法治疗舌前腺囊肿的临床效果，为舌前腺囊肿选择合理的手术方法提供依据。方法：41例舌前腺囊肿患者，均采用手术治疗，随机为两分组，A组19例采用常规小黏液腺囊肿摘除术，B组22例采用患侧舌前腺及囊肿一并摘除的术式。术后随访6个月。结果：A组7例复发，B组1例复发。结论：对于治疗舌前腺囊肿，采用舌前腺及囊肿一并摘除的术式效果确切。     

A profile of organizational characteristics of colleges of dentistry

This study investigated the organizational characteristics of colleges of dentistry as perceived by their deans, associate deans, and department chairs. Likert's Profile of Organizational Characteristics is used to describe the administrative structures of the colleges on a continuum from exploitive/authoritative through benevolent/authoritative and consultative to participatory. In addition, administrators were asked to evaluate their colleges' effectiveness in adapting to an environment of change. The results indicate a relatively low level of participation in administration in contrast to a high desire for participation, and that administrators believe their colleges are only marginally effective in adapting to change.     

Evaluation of Effects of Application of a Citroxain-Containing Dentifrice

The benefits to the patient of the removal of tooth deposits is well documented. Should such removal provide the additional effect of "whitening" the tooth surface, an additional cosmetic benefit would be provided. This study documents that a Citroxain-containing dentifrice provides all of these benefits.     

Assessment of reliability of cineradiographic recording of temporomandibular joint movements

As part of a cineradiographic study of temporomandibular joint movements, the reliability of the apparatus and techniques has been assessed. The areas of concern were the radiographic procedure, tracing apparatus and tracing technique. To assess the accuracy of the radiographic procedure, anatomical and radiographic measurements of mandibular condyles were compared. A range of variation of 0-46--0-8 mm was found, which compared favourably to the only previously published investigation. The use of mechanical devices simulating the fundamentals of mandibular movements suggested that the cineradiographic record showed paths of opening and closing separated more widely than occurred in vivo. The reliability of the tracing apparatus was assessed by calculated misalignments and found to be acceptable. The subjective error in tracing cineradiographic films by a regular observer was investigated by a point location error method. The error was found to be small and within acceptable limits.     

Knowledge of oral health professionals of treatment of avulsed teeth

Abstract –  The management and immediate treatment of an avulsed permanent tooth will determine the long-term survival of the tooth. The aim of this study was to evaluate the knowledge of oral health professionals on the new guidelines for emergency treatment of avulsed teeth. A 12-item questionnaire was distributed among general dentists, specialists, dental hygienists and dental assistants attending Continuing Education courses at the School of Dentistry, University of Southern California, between 2003 and 2004. This study reports only on the general practitioners who comprised 83% of the participants. The results revealed an uneven pattern of knowledge among them regarding the emergency management of an avulsed tooth. Statistically significant associations were related to the participants' previous dental trauma education and their age. In conclusion, there is a need to improve the knowledge of general dentists in the current guidelines for emergency treatment of avulsed teeth.     

The effects of oral administration of chlorhexidine on the rate of regeneration of epithelia of the oral mucosa and skin of mice

Using injection of tritiated thymidine and autoradiography, the labelling index, rate of migration of labelled cells and width of epithelia of the oral mucosa and skin of mice was examined after either (a) 2 % chlorhexidine solution or (b) distilled water, was instilled twice daily for 7 days into the oral cavity. A small but consistent reduction in the rate of regeneration of epithelia in chlorhexidine-treated animals was attributed to the added stress to which the experimental group was exposed. It was anticipated that a direct irritant effect of chlorhexidine on the oral mucosa would produce a locally increased rate of epithelial regeneration: no such change was observed. No change in the labelling index of the liver or in the rate of gain of weight in experimental animals was detected during the experimental period.     

正常青年Monson球面半径的测量研究

目的测量正常青年Monson球面半径。方法选择60名(男30名,女30名)正常青年制取全口印模,应用立体摄影成像的原理与方法对Monson球面半径进行测量和统计学处理。结果Monson球面的半径平均为10.173 cm,大于理论值10.160 cm,差异有显著性(P<0.01);男、女性球面半径差异无显著性。结论本实验所得到的数据可作为全口义齿修复中记录颌位关系的一个参量。     

Development of a specific indicator of the well-being of wearers of removable dentures

Montero J, Bravo M, López‐Valverde A. Development of a specific indicator of the well‐being of wearers of removable dentures. Community Dent Oral Epidemiol 2011; 39: 515–524. © 2011 John Wiley & Sons A/S Abstract – Objectives: Bearers of removable prostheses have certain particular characteristics that require the inclusion of items able to detect the specific effect on their oral functions (derived from the presence of such prostheses). We aimed to develop and validate a specific indicator for the assessment of oral health–related quality of life in bearers of dentures. Methods: A panel of experts compiled a questionnaire addressing oral health–related quality of life (11 items) to assess the degree of well‐being afforded by removable dentures. After a pilot trial in patients bearing prostheses (n = 36), a consecutive sampling of denture wearers (n = 123) was conducted among patients not requesting odontological treatment and accompanying persons, attending their respective health centres in the City of Granada and its metropolitan area. The subjects were classified as RPP1 (removable partial prosthesis on one of the arches, RPP2 (on both) and complete prosthesis (CP on both arches). Results: The questionnaire was consistent (Cronbach alpha 0.814) and proved to have suitable validity. Factor analysis revealed three factors termed physical, psychological and social well‐being, which coherently supported the interrelationship among the 11 items. The prevalence of impact was significantly higher in the CP individuals (97.1%) and in that of the RPP2 group (92.1%) than in the RPP1 subjects (80.7%). Prosthetic fit, aesthetics and self‐confidence were significantly discrepant among the prosthetic groups, although the total prosthetic quality of life score was not able to differentiate them. The main prosthetic impact in all the prosthesis‐wearing groups was attributed to ‘food impaction’, although all the groups were essentially satisfied with their mouth. Conclusions: The prosthetic quality of life (PQL) questionnaire is a valid and reliable indicator of the specific well‐being of partial or complete denture wearers.     

钴铬合金表面粗糙度与细菌黏附

目的：了解临床用软质钴铬合金表面粗糙度与细菌黏附的关系。方法：用Talysurf/S5-CD型表面形貌仪测定六组软质钴铬合金试片表面粗糙度。采用体外黏附试验，了解变形链球菌在软质钴铬合金表面的黏附量受表面粗糙度影响的状况。结果：随着研磨和抛光程序的进行，钴铬合金表面粗糙度逐渐减低，其表面的细菌黏附量也不断减少。其中橡皮轮组和抛光膏组之间的表面粗糙度均值和细菌黏附量无显性差异，其余各组间表面粗糙度均值和细菌黏附量均有显性差异。结论：为减少菌斑附着，制作钴铬合金冠修复体后要重视磨光。     

Estimating the location of the center of resistance of canines

Objective:To develop a method to quickly estimate the location of center of resistance (CR) in mesial-distal (MD) and buccal-lingual (BL) directions from the tooth''s image.Materials and Methods:The maxillary cone-beam computed tomography (CBCT) scans of 18 patients were used. Finite element (FE) models of the canines and their surrounding tissues were built based on their CBCT scans to calculate the locations of CR. Root length, centroid of the contact surface (CCS), and centroid of projection of the contact surface (CPCS) were also obtained from the images. The CCS and CPCS locations were projected on the tooth''s long axis, which were represented as percentages of the root length measured from the root''s apex.Results:Using the FE results as the standards, the errors of using CCS or CPCS to estimate CR were calculated. The average location of CR calculated using the FE method was 60.2% measured from the root’s apex in the MD direction and 58.4% in the BL direction. The location of the CCS was 60.9%. The difference in CR was 0.7% in the MD direction and 2.5% in the BL direction. The location of CPCS was 60.2% in the MD direction and 59.1% in the BL direction, which resulted in a 0.1% and 0.8% difference with the reference CR, respectively. The average difference of CR in the MD and BL directions was small but statistically significant (P < .05).Conclusion:The locations of the CR of a human canine in the MD and BL directions can be estimated by finding the CPCSs in those directions.     

Correlation of types of orbital fracture and occurrence of enophthalmos

We sought to investigate the correlation between type of orbital fracture and occurrence of traumatic enophthalmos. The 119 patients with orbital fractures were divided into the enophthalmos group (71 cases) and the nonenophthalmos group (48 cases). The 2 groups were compared by location and type of orbital fracture based on observation of computed tomography scans. We found the incidence of medial wall fractures significantly higher in the enophthalmos group (76.06%) than in the nonenophthalmos group (22.92%, χ(2) = 32.63, P < 0.05). The incidence of combined medial-inferior wall fractures was also significantly higher in the enophthalmos group (52.93%) than in the nonenophthalmos group (12.5%, χ(2) = 23.21, P < 0.05). However, the incidence of lateral-inferior wall fractures was significantly lower in the enophthalmos group (36.62%) than in the other group (58.33%, χ(2) = 4.11, P < 0.05). In most cases of lateral-inferior orbital wall fracture in the enophthalmos group, the zygomatic complex was displaced toward the lateral-posterior direction. The combined medial-inferior wall fracture is likely the primary type of multiple wall fracture leading to traumatic enophthalmos. Enophthalmos caused by a combined lateral-inferior fracture may be correlated with lateral-posterior displacement of the zygomatic complex.