Tooth wear due to dental attrition among 12-year-old adolescents / Desgaste dentário por atrição entre adolescentes de 12 anos de idade

Aim: To evaluate the prevalence and distribution of tooth wear due to dental attrition among 12-year-old adolescents according to their gender, reports of tooth grinding during sleep/while awake (bruxism), and sleep features related to sleep-disordered breathing. Methods: A cross-sectional study was conducted with 172 adolescents from southeast Brazil. Parents/caregivers answered questions about sociodemographic characteristics; reports of adolescents' tooth grinding during sleep, and sleep features (e.g. sleep duration and position, snoring, drooling on the pillow) in the previous two weeks. Adolescents self-reported the occurrence of tooth clenching/grinding while awake in the previous two weeks. Tooth wear due to dental attrition was assessed by a previously calibrated researcher, using a validated 5-point analogical ordinal occlusal/incisal tooth wear grading scale, with scores ranging from 0 (no wear) to 4 (loss of crown height ≥ 2/3), depending on tooth wear severity. Descriptive statistics and the Mann-Whitney test (p < 0.05) were performed to identify differences in tooth wear due to the distribution of dental attrition, according to adolescents' characteristics. Results: Most adolescents were female (58.0%) and 81.6% of the participants presented tooth wear due to dental attrition within the enamel. Adolescents who snored had a higher number of incisors with tooth wear due to dental attrition (p = 0.035). Females showed a higher number of canines with tooth wear due to dental attrition (p = 0.020). Adolescents whose parents reported tooth grinding during sleep presented a higher number of bicuspids with tooth wear due to dental attrition (p = 0.001). Conclusion:Tooth wear due to dental attrition within the enamel was observed in most adolescents. The distribution, depending on specific groups of teeth, was higher among female adolescents, adolescents' whose parents reported tooth grinding, and adolescents who snored during sleep.

Objetivos: Avaliar a prevalência e distribuição de DDA entre adolescentes de 12 anos de acordo com o sexo, relato de ranger de dentes durante o sono e vigília (bruxismo) e características relacionadas a desordens respiratórias do sono.Método: Desenvolveu-se um estudo transversal com 172 adolescentes do sudeste do Brasil. Seus pais/responsáveis responderam um questionário contendo informações sociodemográficas, relato sobre os filhos rangerem os dentes durante o sono e hábitos do sono dos filhos (duração do sono, posição que dorme, roncar, babar no travesseiro) nas duas últimas semanas. Adolescentes relataram ocorrência de ranger/apertar de dentes durante a vigília nas duas últimas semanas. DDA foi avaliado por um pesquisador previamente calibrado através de uma escala analógica ordinal de cinco pontos de desgaste dentário para faces oclusal/incisal previamente validada, com escores variando de 0 (sem desgaste) a 4 (perda da coroa em altura ≥ 2/3), dependendo da gravidade do desgaste. Análises descritivas e teste de Mann-Whitney (p < 0,05) foram realizados para identificar as diferenças na distribuição de DDA de acordo com as características dos adolescentes.Resultados: A maioria dos adolescentes eram meninas (58,0%) e 81,6% dos participantes apresentaram DDA em esmalte em algum elemento dentário. Adolescentes que rocavam apresentavam mais incisivos com DDA (p = 0.035). Meninas apresentaram maior número de caninos com DDA (p = 0.020). Adolescentes que rangiam os dentes durante a noite apresentaram maior número de pré-molares com DDA (p = 0.001).Conclusão: Desgaste dentário por atrição em esmalte foi observado na maioria dos adolescentes. A distribuição, dependendo de grupos de dentes específicos, foi maior entre meninas, adolescentes que roncavam durante o sono e que rangiam os dentes durante o sono.

A Etiologia da Lesão Cervical não Cariosa: Um Novo Desafio para o Cirurgião-Dentista do Século XXI / The Etiology of Noncarius Cervical Lesions: a New Challenge for the 21ST Century Dentist

O termo Lesões Cervicais Não Cariosas (LCNCs) refere-se à perda de tecido dentário duro na Junção Cemento-Esmalte (JCE), cuja etiologia não está relacionada com o envolvimento bacteriano. A origem e a progressão desses defeitos cervicais são consideradas multifatoriais, sendo atribuídas a três fatores principais, sendo eles: abfração, biocorrosão e abrasão. Tais fatores podem estar combinados e associados a eventos de força excessiva aplicada durante a escovação, juntamente com a abrasividade de dentifrícios, hábitos alimentares e/ou parafuncionais. Essas lesões podem ter morfologias diferentes de acordo com seu fator etiológico principal, podendo se apresentar em forma de cunha, oval ou arredondada. O objetivo deste trabalho foi realizar uma revisão de literatura a fim de apresentar os desafios do Cirurgião-Dentista na descoberta dos diferentes fatores etiológicos das LCNCs. O desafio em questão se dá pelo estudo da combinação desses diversos fatores, bem como a realização de um diagnóstico preciso, fazendo-se necessário o conhecimento adequado da etiologia a fim de prevenir futuras novas lesões, estagnar as existentes e assim, capacitar o Cirurgião-Dentista a realizar um tratamento eficaz e longínquo das LCNCs. No entanto, ainda existem muitas controvérsias na literatura, tornando necessária a elaboração de mais estudos para elucidar a etiologia das LCNCs

The term noncarious cervical lesions (NCCL) refers to the loss of hard tooth tissue at the Cemento-Enamel Junction (CEJ), whose etiology is not related to bacterial involvement. The origin and progression of these cervical defects are considered multifactorial, being attributed to three main factors: abfraction, biocorrosion and abrasion. Such factors may be combined and associated with excessive force events applied during brushing, along with the abrasiveness of dentifrices, eating and/or parafunctional habits. These lesions may have different morphologies according to their main etiological factor, and may be wedge-shaped, oval or rounded. Our aim in this paper was to perform a literature review in order to present the challenges of the dental surgeon in identifying the different etiological factors of NCCL. Such challenge regards the study of the combination of these factors, as well as the achievement of an accurate diagnosis, requiring adequate knowledge of the etiology in order to prevent future lesions, stagnate existing ones, thus enabling the Dental Surgeon to treat NCCL effectively in the long term. However, there are still many controversies in the literature, making it necessary to develop more studies to elucidate the etiology of NCCL

Application of biocopy function of temporary crown occlusal morphology in patients with severe attrition / 北京大学学报(医学版)

OBJECTIVE@#To explore the preliminary application of "biocopy function" in digital technology of temporary crown in severe tooth attrition, so as to reduce the difficulty of final restoration adjustment in severe tooth wear cases, and save clinical time.@*METHODS@#Twelve patients aged between 40 and 65 years with severe tooth attrition were recruited in this study. The experimental group (6 cases, 3 females and 3 males) used the method of digital copy of temporary restoration shape when making the final restoration, and the control group (6 cases, 3 females and 3 males) used the traditional method to make the final restoration. The mean time of central occlusal adjustment and protrusive and lateral occlusal adjustment of each crown, the number of follow-up visits of the patients were recorded and statistically analyzed. The occlusal comfort of the first and the third months after wearing the prosthesis was evaluated by the patients, and the difference of the occlusal comfort of the final prosthesis made by the two methods was compared (the full score was 10 points). The occlusal adjustment time and occlusal comfort score were used as measurement data. Single sample t test was used. The number of follow-up visits was count data. Rank sum test was used for non-normal continuous variables.@*RESULTS@#The mean occlusal time of each crown adjustment in the experimental group was significantly lower than that in the control group (P < 0.01), and the median number of follow-up visits in the experimental group was lower than that in the control group (P < 0.01). The average occlusal comfort score of the experimental group was higher than that of the control group at the first time (P < 0.01). After three months of crown wearing, the median occlusal comfort score of the experimental group was higher than that of the control group (P < 0.05).@*CONCLUSION@#In the case of severe tooth attrition, it is feasible to use the "biocopy function" in the design software to design the final prosthesis, which is conducive to reduce the difficulty of adjustment and achieve predictable functional and aesthetic effects, which is of great significance to save clinical time and improve the accuracy of restoration.

Analysis of enamel and material wear by digital microscope: an in-vitro study

Abstract: The objective of the study was to analyze the surface area (SA) of the wear caused by simulated chewing on human enamel and opposing restorative material, namely: composite resin (CR), porcelain fused to metal (PFM), lithium disilicate (LD), or monolithic zirconia (MZr). Forty-eight premolars were selected as enamel specimens and divided randomly into 4 groups (n = 48; n =12) used as antagonists in chewing simulation (250,000 loading cycles) against one of the four selected test materials. Enamel and material specimens were scanned and evaluated under digital microscope, and wear SA (mm2) were recorded. Descriptive statistics, paired t-test, one-way ANOVA, and post-hoc Tukey-HSD tests were used for statistics (p < 0.05). The smallest and largest SA were exhibited by enamel against LD (0.80 mm2) and PFM (1.74 mm2), respectively. PFM (3.48 mm2) showed the largest SA and CR (2.28 mm2) showed the smallest SA. Paired t-test for SA values showed significant difference (p < 0.05) in all wear comparisons between materials and enamel antagonists. The wear of materials were greater than that of their respective enamel antagonists (p < 0.05). One-way ANOVA of the logarithmic means of wear SA revealed significant differences (P<0.05). Post-hoc Tukey test revealed significance for PFM (p < 0.05) with other materials. Wear of all test materials was greater compared to the wear of enamel antagonists. PFM and LD caused the largest and the smallest enamel wear, respectively. CR, LD, and MZr are more resistant than PFM to wear after simulated chewing against enamel.

Influence of tobacco chewing on oral health: A hospital-based cross-sectional study in Odisha

Background: Smokeless tobacco use in the Indian subcontinent is a part of many religious and cultural rituals and has gained a degree of social acceptance. The deleterious effects of smokeless tobacco are not as well-known as those produced by smoking. Objectives: The study was carried out to assess the influence of tobacco chewing on the oral health of adult patients attending the dental outpatients department of Khordha district headquarter, Odisha. Methods: A hospital-based cross-sectional study was conducted among 25–64-year-old patients attending the dental outpatient department of Gopabandhu Khordha district headquarter hospital. A total of 512 study participants, who were age and sex matched, were stratified into four age groups such as 25–34 years, 35–44 years, 45–54 years, and 55–64 years old. Oral health status of the participants was assessed using modified WHO Oral Health Assessment Form (2013). Pearson's Chi-square test, binary and multinomial logistic regression was performed to determine the relationship between oral health problems and tobacco chewing. Results: Among the tobacco chewers, 59.8% had gingival bleeding, 40.6% had periodontal pockets, 30.1% had loss of attachment, 48.4% had attrition, and 4.3% had potentially malignant disorders. Compared to the nonchewers, these oral problems were significantly higher among the chewers. Whereas dental caries experience was significantly lower among the chewers (40.6%) compared to the nonchewers (54.7%). Compared to the nonchewers, chewers had 1.71 times increased odds for gingival bleeding, 1.71 times increased odds for periodontal pockets, 2.39 times increased odds for loss of attachment, and 2.49 times increased odds for attrition, which were statistically significant. Conclusion: Hence, the study revealed that tobacco chewing definitely had an influence on oral health, with statistically significant increase in oral health problems in chewers compared to nonchewers. Moreover, loss of attachment and potentially malignant disorders increased significantly with the frequency of tobacco chewing. Periodontal pockets, attrition, and loss of attachment significantly increased with the duration of the chewing habit.

Presencia de desgaste dental en la tribu nómada nukak makú del Guaviare: estudio preliminar / Tooth wear in Guaviare’s nomadic tribe nukak maku: preliminary study

Antecedentes: los nukaks makús son un grupo nómada que habita la zona del Guaviare (selva amazónica colombiana), cuya subsistencia se basa en la caza y la recolección, actividades que, como en otras tribus indígenas, pueden relacionarse con el desgaste dental. Hoy en día, esta población indígena está siendo afectada por enfermedades, violencia y el olvido de los gobiernos local y nacional. Objetivo: identificar la presencia de desgaste dental y determinar su localización y distribución de acuerdo con el sexo y la edad en la tribu. Métodos: la población blanco correspondió a 47 personas del asentamiento Barrancón en San José del Guaviare, 25 hombres y 22 mujeres, de los cuales 20 eran adultos y 27 niños. La muestra estuvo conformada por 17 sujetos. Por medio de exploración clínica y modelos de estudio, se clasificó el desgaste dental según la escala de Guerasimov-Zoubov. Resultados: se encontró desgaste dental generalizado, mayor en incisivos que en molares y en mayor grado de severidad en el grupo de edad más avanzada (35 a 45 años) y en la población femenina, donde predominó el desgaste grado 4. Conclusión: la muestra analizada mostró que todos los individuos presentaron desgaste dental probablemente asociado con sus costumbres y medios de subsistencia.

Background: The Nukak Maku is a nomadic group whose subsistence is based mainly on hunting and harvesting, activities that like in others indigenous tribes are related to tooth wear. They live in the area between the Guaviare and Inírida rivers, in the department of Guaviare (Colombian Amazon). Presently, they are severely affected by a combination of illness, violence and neglect by local and national governments. Purpose: Identify the presence of tooth ear, its severity and distribution regarding gender and age. Methods: The target population was 47 peasants living in the Barrancón indigenous shelter nearby the city of San José del Guaviare (25 males and 22 females, 20 adults and 27 children). The sample consisted of 17 of them. Clinical examination was performed and model casts were analyzed in order to determine tooth wear through the Guerasimov-Zoubov scale. Results: Generalized tooth wear was found, which was more severe among incisors than molars. The degree of severity was greater in the older group (35 to 45 years of age) and in the female population, where the grade 4 was more frequent. Conclusions: We believe that all the subjects show tooth wear likely related to their habits and living style.

Má oclusão Classe II, divisão 1, de Angle com discrepância ântero-posterior acentuada / Angle Class II malocclusion with severe anteroposterior disharmony

A má oclusão Classe II de Angle é caracterizada por uma discrepância dentária ântero-posterior, que pode ou não estar associada a alterações esqueléticas. Além do comprometimento estético, o fato de vir associada a um overjet acentuado faz com que o paciente fique mais exposto a traumas dentários. Este caso foi apresentado à Diretoria do Board Brasileiro de Ortodontia e Ortopedia Facial (BBO), representando a categoria 4, ou seja, uma má oclusão com discrepância ântero-posterior acentuada, Classe II com ANB maior ou igual a 5º, como parte dos requisitos para a obtenção do título de Diplomado pelo BBO. Possui uma característica incomum, que é a ausência congênita de um incisivo inferior.

Angle Class II malocclusion is characterized by an anteroposterior dental discrepancy which may or may not be accompanied by skeletal changes. In general, distressed by a significantly compromised facial aspect, patients tend to seek treatment. This case report was submitted to the Brazilian Board of Orthodontics and Facial Orthopedics (BBO) as part of the board certification process, as representative of Category 4, i.e., a Class II malocclusion with severe anteroposterior discrepancy and ANB Angle equal to or bigger than 5º (ANB > 5º). The case involves an unusual event - the congenital absence of one lower incisor tooth.

Age Estimation of Mummies by Dental Attrition: Application of Three-dimensional CT Images

BACKGROUND: Because of the rarity of mummies in Korea and the difficulty in obtaining samples from mummies, studies to determine the ages of mummies are uncommon in Korea. This study was performed to determine the ages of mummies using the information obtained by nondestructive methods to minimize damages to the mummies. METHODS: Three mummies excavated between 2002 and 2004 were used. Three-dimensional reconstructed images of the total teeth were obtained by CT scanning. The age at death was determined according to the 'Age Estimation Table of Dental Attrition' as developed by Takei. Three teeth were extracted from each of three mummies and examined grossly and microscopically by serial sections using the Gustafson-Johanson method. RESULTS: The ages at death of the three mummies estimated by the Takei method were 23.57 years (Yoon mummy), 51.01 years (Bong mummy), and 64.45 years (Black mummy). These results were similar to the ages determined by the Gustafson method. CONCLUSION: Age determination method using a CT scan and three-dimensional reconstruction may be a valuable method because it minimizes the damages to valuable mummies and it gives reliable data similar to that obtained by other standard methods.

Short-term and long-term effects of occlusal rehabilitation on the co-contractration patterns of the electromyography of masticatory muscles / 北京大学学报(医学版)

Objective:To investigate the short-term and long-term effects of occlusal rehabilitation on the co-contractration patterns of masticatory muscles of patients with extensive tooth wear.Methods: Twenty-nine patients with severe tooth wear were selected and conducted with occlusal rehabilitation.The surface electromyography(EMG) of masseter(MM),anterior temporalis(TA) and posterior temporalis(TP) at rest position,during clenching and chewing were separately recorded in the stage of pre-treatment,1 month after temporary restoration,1 month after permanent restoration and long-term observation(mean 3.5 years).The Asymmetry Indexes(AI) of bilateral muscles,Activity Indexes of MM/TA,MM/TP and TA/TP were compared in each stage.Results:(1) After occlusal rehabilitation,all the AIs of bilateral MM,TA and TP at rest position,during clenching and chewing showed obvious decrements.(2) In every stage of occlusal rehabilitation,all of the Activity Indexes of MM/TA at rest position,during clenching and chewing had no obvious changes.(3) The Activity Indexes of MM/TP and TA/TP during clenching and chewing significantly increased after occlusal rehabilitation.Conclusion: The treatment of occlusal rehabilitation can significantly improve the bilateral symmetry of masticatory muscles in patients with extensive tooth wear,and also change the coordinated EMG activity of different masticatory muscles.

Efficacy observation of occlusal rehabilitation in aged people with serious attrition / 医学研究生学报

Objective:To evaluate the efficacy of occlusal rehabilitation in old patients with decreased vertical dimensions caused by serious attrition.Methods:Sixty-five patients with decreased vertical dimension caused by serious attrition were divided into 3 groups according to the defect of dentition and/or TMD.Group A included 42 patients with serious attrition and defection of dentition.Group B had 15 patients with heavy tooth wear,defection of dentition and TMD.Group C included 8 patients with serious attrition and functional TMD.All patients were conducted occlusal rehabilitation at increased vertical dimensions in normal intercuspital position(ICP) by removable denture with occlusal pad and removable occlusal splints.The time of follow-up visit of these patients ranged from 1.5 months to 9 years. Results:The masticatory efficacy of the patients was obviously improved,and all the symptoms of TMD were relieved.Furthermore,the symptoms of TMD were not observed after the treatment in patients without TMD.Conclusion:The results achieved by removable occlusal rehabilitation to aged people with serious attrition and decreased vertical dimension are satisfactory,and suggest that the occlusal rehabilitation is necessary for them.Furthermore,the removable occlusal rehabilitation can be acted as a reference and transition to permanent fixed occlusal rehabilitation.

An own control study on the tooth attrition in natural tooth with cracked tooth syndrome patients / 实用口腔医学杂志

0.05).(2)The relative tooth attrition:significant differences between CTS and control group in upper premolar lingual cusp and lower first molar buccal cusp were found.(3)Tooth cracked direction:it was mesial-distal direction in 91.67% maxillary premolar and 88.89% maxillary second molar in CTS but no obvious direction taxis in first molar and mandibular second molar in CTS.Conclusion:There are close correlations between insufficient tooth attrition in maxillary premolar lingual cusp,mandibular first molar mesial buccal cusp and CTS.

Treatment of serious attrition with defect of dentition in old people / 实用口腔医学杂志

Objective:To summarize the expierence in the prostheti c treatment of serious attrition with defect of dentition in old people. Methods: Removable denture with occlusal pad was one timely prepa red for 32 people aged 58～80 years old with serious attrition and defect of de n tition. 6 of the patients had temporomandibular disturbance (TMD). The time of f ollow up visit of the patients ranged from 2.5 months to 5 years.Res ults: The masticatory function of the patients was improved obviousl y .Unilateral mastication was achieved. The symptom of articulation was all rel ieved.The occlusal relationship was not changed or occlusal vertical dimension ( OVD) was appropriately increased in the patients without TMD. The symptom of TMD did not appear after using denture in patiends with TMD.Conclu sions:During occlusal reconstruction in old people with serious attri tion and defect of dentition, the recovery of OVD and occlusal relationship is v ery important.

Surface electromyogrphy analysis of masticatory muscles in the cases with severe tooth wear / 实用口腔医学杂志

Objective: To study the masticatory muscles activity in the cases with severe tooth wear(TW) and the damaged display of masticatory muscles in different types of occlusal wear. Methods: The electromyography(EMG) of bilateral anterior temporalis(TA), masseter muscle(MM) and anterior digastric(DA) was taken in 15 elder patients aged 49～69 years old with TW, the EMG of the patients was compared with that of 8 healthy subjects aged 49～55 years old. Results: TW patients showed higher activity of TA,MM and DA in mandibular postural position than the controls (P

Nueva técnica de acceso cameral y localización de los conductos en molares permanentes

Se presenta una nueva técnica de acceso cameral y de localización de los conductos que utiliza un punto de referencia fijo para todos los molares desde el cual se retira el techo de la cámara pulpar mientras se localizan los conductos. Así se garantiza, con mayor rapidez, la exploración del 100 % del conducto mesiovestibular, incluso en molares difíciles y por personal poco adiestrado.

A cavity access and canal location technique is presented in this paper. It uses a fixed bench mark for all the molars from which the tegmen of the pulpar cavity is removed while canals are located. In this way, we guarantee a faster 100 % scanning of mesiovestibular canals, even in difficult molars, by a personnel with low level of training.