[Hora est. The relationship between stress, salivary proteins and caries experience in children]. / Serie: Hora est. De relatie tussen stress, speekseleiwitten en cariëservaring bij kinderen.

Dental caries is a major public health problem and untreated caries has serious consequences for children. Psychosocial factors have multiple consequences, among others on the composition of saliva. Therefore, this study investigated whether stress and various salivary protein levels are associated with dental caries experience in children. The activity of the Matrix Metalloproteinases MMP-8 and MMP-9 and the total proteolytic activity in saliva turned out to be indicators for the caries experience. Salivary Alpha-Amylase seems to be a protector and was a strong indicator for caries experience. In cases where children were exposed to two different dental treatments, the level of salivary cortisol- and alpha-amylase increased, in which a distinction could be made between non-invasive and invasive treatment. The results of the study emphasise the need for further research into the way stress and salivary protein concentrations can affect the caries experience and how different dental treatments can influence the behaviour and stress levels in children.

Human adult dental pulp CD117/c-kit-positive networks of stromal cells.

Dental pulp tissue was collected from 6 healthy adult patients, prior to prosthetic treatments, in order to evaluate the in situ phenotype of dental pulp stromal cells and compare with that of dental pulp stem cells. A CD34-/CD44+/CD105-/CD117+/CD146-/nestin- phenotype of stromal cells in the dental pulp core was found. Cells with a similar phenotype, but CD44-, were found in the cell richzone. Dental pulp stromal networks (DPSNs) were found CD117+/CD44+ in the pulp core, but CD117+/CD44- in the cell rich zone. The c-kit-positive DPSNs were contacting pulp nerves and were, in this regard only, comparable to interstitial Cajal cells. Stromal signalling in dental pulp needs further evaluation, in normal tissue as well as a possible cause of persisting pain after endodontic treatments.

Investigation of six selected bacterial species in endo-periodontal lesions.

AIM: To investigate and determine possible associations of six tested bacteria belonging to 'orange' and 'green' complexes, in endo-periodontal lesions: Parvimonas micra, Fusobacterium nucleatum, Campylobacter rectus, Eubacterium nodatum, Eikenella corrodens and Capnocytophaga sputigena. METHODOLOGY: Forty-six patients presenting with different types of endo-periodontal lesions were investigated. Clinical examinations, periapical radiographs and microbiological sampling from the canal system (endo) and periodontal pockets (perio) were performed. Qualitative and semiquantitative evaluation of bacteria was performed by polymerase chain reaction (PCR) and DNA-DNA hybridization (micro-IDent plus; Hain Lifescience, Germany). RESULTS: Extremely high bacterial loads in endodontic samples were recorded for P. micra, F. nucleatum and C. sputigena, while periodontal samples were often colonized by the same species, plus C. rectus. Significant association was recorded between F. nucleatum-endo and P. micra-endo (P = 0.03, Fisher's exact test). There was marginal evidence of associations between: (i) C. sputigena-endo and C. sputigena-perio (P = 0.06, Fisher's exact test); (ii) P. micra-endo and P. micra-perio (P = 0.05, Fisher's exact test). Sensitivity to percussion was associated with an increased chance of cases with P. micra-endo (P = 0.03, Pearson chi-square test). CONCLUSION: The findings suggest that F. nucleatum, P. micra and C. sputigena may play a role in the pathogenesis of endo-periodontal lesions.

The extramandibular inferior alveolar nerve in cases with severely atrophic lower jaws.

There are very few evidences on the extramandibular course (EMC) of the inferior alveolar nerve (IAN). We report here two such cases. The first one was encountered at dissection, in a human adult female cadaver where the right IAN terminal division was identified in the premolar region, above a severely atrophied mandibular body. The second case was a patient evaluated by cone-beam CT, who presented with an extremely atrophic mandible with bilateral extramandibular courses of the IANs. Such severe atrophy of the mandible may be considered as residual ridge class 7 along with the existing Atwood classes. EMCs of the IAN may not only occur in extreme mandibular atrophy, but also in dentate mandibles. In edentulous mandibles, an extramandibular IAN may complicate local surgical procedures or hamper denture wearing.

Immunohistochemical expression of non-collagenous extracellular matrix molecules involved in tertiary dentinogenesis following direct pulp capping: a systematic review.

BACKGROUND: Extracellular matrix molecules (ECMM) expression during tertiary dentinogenesis provides useful information for regenerative applications and efficacy of pulp capping materials. AIM: To identify and review the expression and roles of non-collagenous ECMM after successful direct pulp capping (DPC), following mechanical pulp exposures, via immunohistochemistry (IHC). The study addressed the question of where will successful DPC impact the IHC expression of these molecules. DATA SOURCES: In vivo animal and human original clinical studies reporting on ECMM in relation to different follow-up periods were screened and evaluated via descriptive analysis. The electronic literature search was carried out in three databases (MEDLINE/PubMed, Web of Science, Scopus), followed by manual screening of relevant journals and cross-referencing, up to December 2018. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS, AND INTERVENTIONS: Randomized and non-randomized controlled trials, conducted in humans and animals, were selected. Histological evidence for tertiary dentine formation was a prerequisite for IHC evaluation. STUDY APPRAISAL AND SYNTHESIS METHODS: The methodological quality of the included articles was independently assessed using the Systematic Review Centre for Laboratory animal Experimentation (SYRCLE) and the Cochrane risk of bias tool (RoB 1), respectively. RESULTS: From a total of 1534 identified studies, 18 were included. Thirteen papers evaluated animal subjects and five studies were carried out on humans. In animals and humans, fibronectin and tenascin expressions were detected in pulp and odontoblast-like cells (OLC); dentine sialoprotein was expressed in both soft and newly-formed mineralized tissue. In animals, bone sialoprotein was early expressed, in association with OLC and predentin; the immunoreactivity for dentine sialophosphoprotein and dentine matrix protein-1 was associated with the OLC and dentine bridge; osteopontin was expressed in OLC, predentine and reparative dentine. A considerable heterogeneity was found in the methodologies of the included studies, as well as interspecies variability of results in terms of time. CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: Within the limited scientific evidence, all non-collagenous ECMM expressions during tertiary dentinogenesis are active and related to soft and hard tissues. There is a shortage of human studies, and future research directions should focus more on them. PROSPERO Protocol: CRD42019121304.