What is the relation between the presence of caries in the deciduous dentition and the chronology of the eruption of the permanent teeth?

Based on data obtained from a prospective epidemiological study in a random sample of 4468 Flemish children, accurate emergence ages for permanent teeth could be established. When data on permanent tooth emergence in different populations are compared, differences are most pronounced for premolars. Several authors hypothesised that this difference could be explained by a difference in caries experience in the primary molars. The purpose of this study was to quantify the effect of caries experience in a primary molar on the timing of emergence of its successor. The results indicate that the emergence of the premolars was accelerated by 2 to 8 months when its predecessor had been decayed and or filled but had not been extracted. Premature loss of maxillary primary molars resulted in a significant acceleration of the emergence of the premolars; this was not observed in the mandible. In conclusion, when considering permanent tooth emergence ages, caries experience in the primary dentition should be taken into account.     

Should teeth be extracted immediately in the presence of acute infection?

Immediate extraction of teeth in the setting of an acute infection has shown to be beneficial for many reasons. It results in faster resolution of the infection, decreased pain, and earlier return of function and oral intake. The risk of seeding the infection into deeper spaces by performing immediate extraction is low.     

Does the presence of maxillary midline diastema influence the perception of dentofacial esthetics in video analysis?

ObjectiveTo evaluate the influence of a midline diastema on dentofacial esthetic perceptions of orthodontists, restorative dental specialists or prosthodontists, and laypersons in a frontal facial evaluation performed by means of video.Materials and MethodsTwo individuals aged between 20 and 25 years, one of each gender, with presence of a midline diastema were selected. An acrylic resin mockup was made of the maxillary anterior region, simulating ideal conditions of smile esthetics. Four standardized frontal view videos of the complete face were filmed of each individual in the following situations: with the ideal smile (unchanged mockup) and with the presence of midline diastemas of 0.5, 1.0, and 1.5 mm created by the mockup. In all videos, the patient said a certain sentence and, at the end, simulated a posed smile. Dentofacial esthetic perceptions of all four videos of each individual were evaluated by 51 orthodontists, 51 restorative dental specialists or prosthodontists, and 51 laypersons by means of visual analog scales. Data were evaluated using analysis of variance and Tukey post hoc test, with the level of significance set at 5%.ResultsThe most attractive videos for all groups of examiners were those without diastema and with a diastema of 0.5 mm, for both the woman and the man. For a diastema of 1 mm or 1.5 mm, the dentofacial characteristics were considered unesthetic.ConclusionsDiastemas equal to or greater than 1 mm negatively influence dentofacial esthetics in a frontal facial evaluation performed by means of video.     

Does the presence of mandibular third molars increase the risk of angle fracture and simultaneously decrease the risk of condylar fracture?

Previous studies have shown that impacted mandibular third molars (M3s) increase the risk of mandibular angle fractures and decrease the risk of mandibular condylar fractures. This study attempted to verify these relationships and identify the influence of mechanism and cause of injury. The incidence of fractures was compared in 700 patients with and without impacted M3s. The results showed that patients with impacted M3s had a lower risk of condylar fracture and a higher risk of angle fracture than those without impacted M3s when injured by moderate trauma force. Such relationships could not have been identified when patients were injured by high trauma force. Patients with impacted M3s had a higher risk of angle fracture than those without impacted M3s no matter how they were injured (assault, fall, motor vehicle accident, other). When patients were injured by assault or in a motor vehicle accident, those with impacted M3s were less likely to have a condylar fracture. M3s were a dominant factor for developing a mandibular angle fracture and preventing condylar fracture. The risk of angle fracture was much more affected by impacted M3s than that of condylar fracture, when injury mechanism and cause were taken into consideration.     

Does the presence of an occlusal indicator product affect the contact forces between full dentitions?

Studies have explored occlusal marking interpretation, repeatability and accuracy. But, when an occlusion detection product is interposed between teeth, direct tooth–tooth occlusal contact relationships are replaced by tooth‐material‐tooth structures. Thus, the marks cannot reflect the original contacts. This has been shown for single tooth pair contacts. The purpose of this laboratory study was to similarly examine full dentitions. A dentiform was set into Class I centric occlusion with the mandible supported by a load cell. The maxillary arch was guided by precision slides. As the weighted (~52 N) upper assembly was lowered onto and raised off the mandibular arch, the loads on the mandible were measured. With and without (control) occlusal marking material, the steps were as follows: (cleaning – control 1 – material 1) … (cleaning – control 6 – material 6). The six materials were as follows: Accufilm I and II, Rudischhauser Thick and Thin, Hanel Articulating Silk and T‐Scan. Then, the six sets of (cleaning – control – material) measurements were repeated with the mandibular assembly shifted, in turn, by 0·1 mm in the Anterior, Posterior, Right and Left directions. The five (Centric and four 0·1 mm shifted) occlusal relationships produced grossly different tooth–tooth (control) load profiles. And, in general, these controls were affected, in different ways, by the marking products. Among the five conventional products, the Rudischhausers fared the worst and the electronic T‐Scan was an extreme outlier. Thus, in general, popular occlusal detection products alter the occlusal contact forces, and therefore, their markings cannot characterise the actual occlusion.     

Does the presence of maxillary central incisor edge asymmetry influence the perception of dentofacial esthetics in video analysis?

Objective:To investigate the influence of incisal edge asymmetry of the maxillary central incisors on dentofacial esthetics among orthodontists, prosthodontists, and laypersons using video analysis.Materials and Methods:Full-face films of a 52-year-old afro-descendant woman displaying various levels of incisal wear in the esthetic zone were captured. An acrylic resin mockup was made of the maxillary anterior region, enabling the reproduction of an attractive smile and restoring tooth wear. Four different levels of incisal asymmetry between the upper central incisors in 0.5 mm increments were prepared from this mockup. A film was made for each level of asymmetry (0.5, 1.0, 1.5, and 2.0) and one with no asymmetry, with the patient repeating a sentence, totaling five films. After a pilot study and sample calculation, the films were evaluated by 138 examiners: 46 orthodontists, 46 laypeople, and 46 prosthodontists. Each examiner evaluated the dentofacial esthetics of each film using visual analog scales. Data collected were statistically analyzed.Results:Highest scores were awarded to the film with no asymmetry between upper centrals and the one with 0.5 mm of asymmetry. The asymmetries of 1.5 mm and 2.0 mm had the lowest scores from all three groups.Conclusions:The results of this video analysis indicate that asymmetries equal to or greater than 1.0 mm between the upper central incisors edges jeopardize dentofacial esthetics.     

Is there a positive relationship between molar incisor hypomineralisations and the presence of dental caries?

International Journal of Paediatric Dentistry 2013; 23: 116–124 Objective This epidemiological study aimed to compare the caries experience in 10‐year‐olds with and without molar incisor hypomineralisation (MIH). Methods About 693 children from an ongoing birth cohort study (GINIplus10) were examined for caries lesions to determine the DMF index. Furthermore, enamel hypomineralisation (EH) was scored on all permanent teeth/surfaces, according to the criteria of the European Academy of Paediatric Dentistry. Children with EH were categorised into those with a minimum of one EH in the permanent dentition (MIH/1), with EH on at least one‐first permanent molar (MIH/1A), on at least one‐first permanent molar and permanent incisor (MIH/1B), and on other permanent teeth (MIH/1C). Results The mean caries experience was 0.4 (SD 0.9) DMFT. Existence of MIH/1, MIH/1A, MIH/1B, and MIH/1C was determined in 36.5%, 14.7%, 9.4%, and 21.8% of all children. The corresponding DMFT values were the following: no MIH: 0.3 (SD 0.8); MIH/1: 0.5 (SD 0.9); MIH/1A: 0.5 (SD 0.9); MIH/1B: 0.4 (SD 0.9); and MIH/1C: 0.4 (SD 0.9) DMFT. No significant differences were found between all groups. Conclusions There was no relationship between the presence of EH/MIH and caries in 10‐year‐olds. A ratio of one EH‐associated defect to two caries lesions indicates that both conditions are prevalent and influence the oral health status of 10‐year‐old children from Munich, Germany.     

Intraoral adenoid cystic carcinoma: is the presence of perineural invasion associated with the size of the primary tumour,local extension,surgical margins,distant metastases,and outcome?

Adenoid cystic carcinoma is the most common malignancy of the minor salivary glands, and its biological behaviour is characterised by slow and indolent growth; rare involvement of regional lymph nodes; a high propensity for perineural invasion; multiple or delayed recurrences, or both; and a high incidence of distant metastases. Our aim was to find out the relation between the presence of perineural invasion and these factors. Between 1 January1984 and 1 May 2008, 26 cases of adenoid cystic carcinoma of the intraoral salivary glands, which had initially been treated surgically, were reviewed retrospectively. The most common site was the palate, and perineural invasion was reported in 13 of the 26 resected specimens. There was no significant association between it and the size of the primary tumour (OR = 1.0; p = 1.00), invasion of the surgical margins (OR = 2.08; p = 0.4), the presence of distant metastases (OR = 3.43; p = 0.197), or local control (p = 0.76). It was exclusively present in patients with local extension, and was significantly associated with outcome (p = 0.04). Resection with clear margins is the gold standard of care for patients with intraoral adenoid cystic carcinoma, and the role of adjuvant irradiation remains controversial. Given its paradoxical and complex biological behaviour, large studies with long term follow-up are needed to define the clinicopathological and immunohistochemical variables associated with outcome, as well as the optimal treatment.