Selective excavation and ozone therapy: new frontier of mini-invasive caries treatment in MIH paediatric patients. A case report.

BACKGROUND: The term hypomineralisation of molars and incisors (MIH), introduced in 2001 by Weerheijm et al., describes a clinical state of hypomineralisation of permanent molars with frequent involvement of the incisors. MIH is considered a global dental problem with a prevalence ranging from 2.4% to 40.2% in the entire world paediatric population. The continuous increase in the prevalence of enamel anomalies, including MIH, indicates the need to define new intervention protocols based on the technological advances that are revolutionising paediatric dentistry. The use of ozone associated with the selective and minimally invasive excavation of the dental tissue combines the antibacterial properties of the gas with an ultra-conservative approach aimed at the maximum conservation of the dental tissue. The operative protocol described can be an important tool in the prevention and treatment of MIH. The aim of this work is to illustrate an operative clinical protocol based on the combined use of selective excavation and ozone for the treatment of carious lesions in paediatric patients with MIH.

Exploring late Paleolithic and Mesolithic diet in the Eastern Alpine region of Italy through multiple proxies.

OBJECTIVES: The analysis of prehistoric human dietary habits is key for understanding the effects of paleoenvironmental changes on the evolution of cultural and social human behaviors. In this study, we compare results from zooarchaeological, stable isotope and dental calculus analyses as well as lower second molar macrowear patterns to gain a broader understanding of the diet of three individuals who lived between the end of the Late Pleistocene and the Early Holocene (ca., 17-8 ky cal BP) in the Eastern Alpine region of Italy. MATERIALS AND METHODS: We analyze individuals buried at the sites of Riparo Tagliente (Verona), Riparo Villabruna, and Mondeval de Sora (Belluno). The three burials provide a unique dataset for diachronically exploring the influence of climatic changes on human subsistence strategies. RESULTS: Isotopic results indicate that all individuals likely relied on both terrestrial and freshwater animal proteins. Even though dental calculus analysis was, in part, hindered by the amount of mineral deposit available on the teeth, tooth macrowear study suggests that the dietary habits of the individuals included plant foods. Moreover, differences in macrowear patterns of lower second molars have been documented between Neanderthals and modern humans in the present sample, due to a prevalence of Buccal wear among the former as opposed to higher values of Lingual wear in modern human teeth. DISCUSSION: Isotopic analyses have emphasized the contribution of animal proteins in the diet of the three foragers from the Eastern Alpine region. The possible intake of carbohydrate-rich plant foods, suggested by the retrieval of plant remains in dental calculus, is supported by the signal of macrowear analysis. Moreover, the latter method indicates that the distribution of macrowear in lower second molars (M2 s) allows us to discriminate between Neanderthals and modern humans within the present reference sample. Overall, our results show these three prehistoric hunter-gatherers were well adapted to the environment in which they lived exploiting many natural resources.

Effectiveness of the ozone application in two-visit indirect pulp therapy of permanent molars with deep carious lesion: a randomized clinical trial.

OBJECTIVES: The aim of this randomized, three-arm parallel, single-blinded clinical trial was to evaluate the clinical and microbiological effectiveness of the ozone application in two-visit indirect pulp therapy. MATERIALS AND METHODS: One hundred five lower first molar teeth with deep caries lesion were included and randomly assigned three groups to apply the two-visit indirect pulp therapy. Treatment procedure was applied without any disinfectant (control), with 60-s 2% chlorhexidine digluconate (CHX) or 60-s ozone application. In four different stages (after initial excavation, ozone/CHX application before the temporary restoration, 4 months later immediately after removing temporary restoration, and final excavation), dentin humidity, consistency, and color properties were recorded to evaluate the clinical characteristics of the tissue, and standard dentin samples were collected for the microbiological analysis of mutans streptococci, lactobacilli, and the total number of colony-forming units. The data were analyzed by using Mann-Whitney U test for multiple comparisons. RESULTS: The remaining dentin became harder, drier, and darker after 4 months in all groups. However, CHX and ozone application were statistically better than the control group (p < 0.05). There was a gradual decrease in the total number of microorganisms in all groups. While cavity disinfectant applications were improved the antibacterial efficacy (control, 79.11%; CHX, 98.39%; ozone, 93.33%), CHX application exhibited a greater significant reduction than both groups (p = 0.000). CONCLUSION: The two-visit indirect pulp therapy yielded successful results for all study groups. However, CHX would be conveniently preferable due to improving the treatment success. CLINICAL RELEVANCE: The two-visit indirect pulp therapy applied with cavity disinfectant is a proper alternative treatment procedure in deep carious lesions, instead of conventional technique.

Immunoprotective effects of a hemin-binding peptide derived from hemagglutinin-2 against infection with Porphyromonas gingivalis.

The principal etiologic agent in periodontal disease, Porphyromonas gingivalis, generates cysteine proteases that bind heme with domains such as hemagglutinin-2 (HA2). High-affinity HA2-hemin binding supplies the porphyrin and ferric iron needed for growth and virulence. The DHYAVMISK peptide, recently identified at the hemin-binding site of HA2, inhibits hemin binding. We now evaluate the protective effect of vaccination with DGFPGDHYAVMISK (termed DK) against P. gingivalis using a rat infection model. Rats immunized with DK generated anti-peptide serum IgGs and salivary sIgAs (as measured by ELISA). In a subcutaneous abscess model, the protective effect of immunization was then investigated by measuring abscess size following subcutaneous injection with P. gingivalis. In an oral infection model, a ligature inoculated with P. gingivalis was used to induce periodontitis. The degree of bone erosion, ordinarily provoked by infection, was then evaluated by micro-computed tomography. We found that anti-peptide antibody titers of serum IgGs and salivary sIgAs for rats immunized with DK and adjuvant were significantly higher than for sham-immunized rats (injected with adjuvant/PBS alone; P < .05). In the subcutaneous abscess model, the DK + adjuvant-vaccinated rats recovered faster than sham-vaccinated animals, with their abscess sizes significantly smaller (P < .05). Further, in the experimental periodontitis model, bone loss at the molar palatal side for DK + adjuvant-vaccinated rats was significantly lower than for sham-vaccinated animals (P < .05). Collectively, these data demonstrate the potential of (DK) peptide immunization in terms of eliciting an immunoprotective effect against infection with P. gingivalis.

Curcumin photodynamic effect in the treatment of the induced periodontitis in rats.

This study assessed the effect of curcumin as a photosensitizer in antimicrobial photodynamic therapy (aPDT) for the treatment of induced periodontitis in rats. Periodontitis was induced via a ligature around the mandibular first molar on the left side of 96 rats. The ligature was removed 7 days later, and the animals were randomized into four groups: NT, no local treatment; CUR, irrigation with curcumin solution (40 µM); LED, irradiation with a light-emitting diode (LED, InGaN, 465-485 nm, 200 mW/cm2, 60 s); and aPDT, irrigation with curcumin solution (40 µM) followed by irradiation with LED. Eight animals from each group were euthanized at 7, 15, and 30 days post-treatment. Treatments were assessed using alveolar bone loss (ABL) in the furcation region using histological, histometric, and immunohistochemical analyses. Rats treated with aPDT exhibited less ABL at 7 days compared to the NT group, moderate pattern immunolabeling for osteoprotegerin at 30 days, and a pattern of immunolabeling for RANKL from moderate to low. Treatments resulted in smaller numbers of TRAP-positive cells compared to the NT group. aPDT as monotherapy using curcumin as a photosensitizer and LED as the light source was effective in the treatment of induced periodontitis in rats.

Evaluation of Apically Extruded Debris using Two Niti Systems Associated with Two Irrigation Techniques in Primary Teeth.

PURPOSE: The aim of this study was to compare the effects of 2 NiTi file systems [Twisted File Adaptive (TFA) and Reciproc (RP)] and 2 irrigation techniques [Conventional needle irrigation (CNI) and Laser activated irrigation (LAI)] on the amount of apically extruded debris in primary maxillary molars. STUDY DESIGN: Sixty extracted primary maxillary molars were randomly divided into 4 groups. The mesio-buccal roots of teeth in 4 groups were instrumented using TFA with LAI, RP with LAI, TFA with CNI and RP with CNI respectively. Debris extruded during instrumentation was collected into Eppendorf tubes and amounts were determined. The data were analyzed using two-way ANOVA test at 0.05 level of significance. RESULTS: The results indicated all instrumentation and irrigation systems caused a measurable apical extrusion of debris. However, no statistically significant difference in debris extrusion was observed between irrigation techniques or instrumentation systems (P > 0.05). The total amount of debris extruded apically by LAI was greater than that by CNI. CONCLUSIONS: All instrumentation and irrigation techniques caused debris extrusion. However, the optimal laser activation time and power settings should be investigated to ensure minimal extrusion of debris and irrigant due to cavitation and pressure during LAI in root canal treatment.

Adjunct Antimicrobial Therapy and Periodontal Surgery to Treat Generalized Aggressive Periodontitis: A Case Report.

Here we report a case of generalized aggressive periodontitis treated with periodontal therapy including adjunct antimicrobial therapy and periodontal surgery. The patient was a 22-year-old woman who presented with the chief complaint of gingival recession. Baseline examination revealed generalized plaque deposition and gingival inflammation. Thirty-nine percent of the sites had a probing depth (PD) of 4-6 mm and 2% a PD of ≥7 mm; 63% exhibited bleeding on probing (BOP). Radiographic examination revealed vertical bone loss in the molars and horizontal bone loss in other teeth. Microbiological examination of subgingival plaque revealed the presence of Aggregatibacter actinomycetemcomitans and Tannerella forsythia. Oral health-related quality of life was assessed as a measure of patient-reported outcome. Based on a clinical diagnosis of generalized aggressive periodontitis, initial periodontal therapy and adjunct antimicrobial therapy were implemented. After reducing inflammation and subgingival bacteria, open flap debridement was performed for teeth with a PD of ≥4 mm. Reevaluation showed no sites with a PD of ≥5 mm, a minimal level of BOP, and a marked reduction in the level of the targeted periodontal pathogens. The patient's oral health-related quality of life was slightly worsened during supportive periodontal therapy (SPT). Implementation of adjunct antimicrobial therapy targeting periodontal pathogens and subsequent periodontal surgery resulted in improvement in periodontal and microbiological parameters. This improvement has been adequately maintained over a 2-year period. However, additional care is necessary to further improve the patient's oral health-related quality of life during SPT.

Tratamiento con pasta 3 Mix-MP en molares primarios no vitales: estudio preliminar / Treatment of nonvital primary molars with 2 Mix-MP paste: a preliminary study

Estimar la frecuencia de éxito clínico-radiográfico del tratamiento endodóntico no instrumentado con pasta 3Mix-MP en molares primarios con diagnóstico de necrosis pulpar. Materiales y métodos: estudio experimental, prospectivo y longitudinal, realizado en la Cátedra de Odontología Integral Niños de la FOUBA (agosto 2014 - agosto 2015). Formaron parte de la investigación 44 molares primarios con diagnóstico de necrosis pulpar, de 36 niños (6,07 +/- 1,63 años), sin compromiso inmunológico ni metabólico y que junto con sus responsables legales brindaron el consentimiento informado. Se realizó el tratamiento endodóntico no instrumentado con pasta 3Mix-MP (metronidazol, minociclina, ciprofloxacina 1:1:1 y vehículos macrogol, propilenglicol 1:1) y restauración definitiva con corona de acero. Los molares fueron evaluados por dos examinadores al mes, 3, 6 y 12 meses. Se calcularon porcentajes con sus intervalos de confianza del 95 por ciento. Resultados: al mes, la tasa de éxito clínico fue de 97.72 por ciento (87.96-99.97) y la de éxito radiográfico de 93.18 por ciento (81.31-98.61). Fue posible el seguimiento del 65.85 por ciento de la muestra a los 3 meses, del 34.14 por ciento a los 6 meses y del 24.39 por ciento a los 12 meses, revelando un 100 por ciento de éxito clínico-radiográfico en los tratamientos evaluados. Conclusión: en los casos y períodos estudiados, esta terapéutica mostró un buen comportamiento clínico y radiográfico. Son necesarios estudios con mayor tamaño muestral y mayor período de seguimiento para proponerla como alternativa de tratamento...

Clinical, mineral and ultrastructural changes in carious dentin of primary molars after restoration.

INTRODUCTION: Partial caries removal has been shown to be an effective method to treat deep carious lesions in deciduous teeth. Nevertheless, the possibility of keeping infected dentin in the cavity still requires additional investigation. The objective of this research was to describe changes in primary infected dentin after restoration with glass ionomer cement. METHODS: Dentin from 45 primary molars with deep and active carious lesions was evaluated using clinical and laboratory criteria, before and 60 days after restoration. The clinical analysis evaluated dentin colour (CO), dentin consistency (COS) and laser fluorescence (LF). The laboratory procedures assessed bacterial contamination and mineral content (MC), and evaluated the dentin ultrastructure and collagen content. Data on CO, COS, LF and colony forming units were analysed using the Wilcoxon signed-rank test; MC, bacterial counts and collagen evaluations were evaluated using the Student's t-test. RESULTS: After 60 days, lower values of LF were observed, together with a lower bacterial count, and a higher COS was found, with an increase in calcium, phosphorus and collagen contents. Differences were not detected for CO or for fluorine content. Baseline samples showed enlarged tubules with bacterial invasion; 60-day samples showed better organised tissue, with a more compact intertubular dentin and narrower tubules. CONCLUSION: It is concluded that appropriate cavity sealing can promote beneficial changes in deep carious lesions of primary teeth, even in the presence of infected dentin.

Effect of a single dose of low-level laser therapy on spontaneous and chewing pain caused by elastomeric separators.

INTRODUCTION: The aim of this study was to see the effect of a single dose of low-level laser therapy on spontaneous and chewing pain after the placement of elastomeric separators. METHODS: Eighty-eight patients were randomly selected for this single-blind study. Elastomeric separators were placed mesial and distal to the permanent first molars in all quadrants. Both arches were divided into experimental and control sides. The experimental sides were treated with low-level laser therapy on 3 points on the buccal mucosa for 20 seconds each, with a 940-nm gallium-aluminum-arsenic diode laser on continuous mode and power set at 200 mW. The other side received placebo laser therapy without turning on the laser. A numeric rating scale was used to assess the intensity of spontaneous and chewing pain for the next 7 days. The independent sample t test and repeated-measures analysis of variance with the post hoc Tukey test was used to analyze the results. RESULTS: Significant differences were found in spontaneous and chewing pain among both groups (P <0.05). CONCLUSIONS: A single dose of low-level laser therapy can be an efficient modality to reduce the postoperative pain associated with the placement of elastomeric separators.

Regenerative Endodontic Treatment of an Immature Necrotic Molar with Arrested Root Development by Using Recombinant Human Platelet-derived Growth Factor: A Case Report.

Regenerative endodontic treatment has provided a treatment option that aims to allow root maturation. The present report describes the regenerative endodontic treatment of a necrotic, immature molar by using recombinant human platelet-derived growth factor (rhPDGF-BB) and shows the continued root maturation in the tooth with arrested root development. A regenerative endodontic procedure that used a growth factor was performed for a necrotic molar with arrested root formation in a 20-year-old patient. Thorough disinfection by using mechanical instrumentation and copious irrigation of antimicrobial agents as well as intracanal medication with calcium hydroxide was performed throughout the first 2 appointments. At the third appointment, the root canals were irrigated with an antimicrobial solution and 17% EDTA, and bleeding was evoked by passing sterile paper points beyond the apex in each canal. Small pieces of a collagen membrane saturated with rhPDGF-BB solution from GEM 21S were packed into each canal. Mineral trioxide aggregate was placed, and Cavit and composite resin were used to restore the tooth. Complete root maturation and resolution of a periapical radiolucency were observed at the 15-month follow-up. The present report presents a regenerative endodontic procedure that uses rhPDGF-BB for a necrotic molar with arrested root development. The finding of continued root development in the present case suggests that regenerative endodontic treatment may be able to resume the root maturation process in teeth with arrested root formation. Further clinical studies are required to investigate the efficacy of rhPDGF-BB in regenerative endodontic treatment.

Remineralization Capacity of Three Fissure Sealants with and without Gaseous Ozone on Non-Cavitated Incipient Pit and Fissure Caries.

OBJECTIVE: The purpose of this study was to investigate the remineralization activation of the application of three fissure sealants (FSs), alone or with gaseous ozone (GO), on non-cavitated initial caries and evaluate the clinical success of FS. STUDY DESIGN: Sixty children who had DIAGNOdent scores between 10-30 on bilateral symmetric mandibular first permanent molars were included in study. In a split-mouth design, teeth were assigned to experimental (with GO) and control (without GO) groups. GO was applied to teeth on one side and then the same brand of randomly selected FSs was applied to the teeth on both sides. Children were divided into 3 groups based on type of FS (Group 1: Aegis {Bosworth Co, North Hamlin Avenue Skokie, Illinois, USA}, Group 2: Fuji Triage {GC, Tokyo, Japan}, Group 3: Helioseal {Ivoclar Vivadent, Liechtenstein, Germany}). All FSs were then examined for retention rates at 1, 3, 6, 9, and 12 months; at the end of 12 months, all FSs were removed with an air-abrasion device and DIAGNOdent scores noted to compare with the initial values. RESULTS: The application of GO with either Fuji Triage or Aegis FS was effective on remineralization (p<0.05); however, the application of Helioseal FSs was not effective (p>0.05). The 1(st) and 12(th) months' full retention rates of Fuji Triage FSs was a significant difference (p<0.05) from other FSs (Aegis and Helioseal) (p>0.05). CONCLUSIONS: GO+Aegis FS showed the highest remineralization; and, at the end of 12 months, its clinical success was higher than other FSs.

Effects of low-level laser therapy on osteoblastic bone formation and relapse in an experimental rapid maxillary expansion model.

AIMS AND OBJECTIVES: The aim of this study was to investigate the effects of low-level laser therapy (LLLT) on osteoblastic bone formation and relapse during expansion of rat palatal sutures. MATERIALS AND METHODS: Thirty-two Wistar rats were randomly allocated into two groups of 16 rats each. In the first group, LLLT was applied 4 days after expansion commenced. Seven days after expansion, retainers were applied for 10 days. The second group was similarly treated, with the exception of laser therapy. All rats were sacrificed on day 7 (n = 1) (the end of the expansion period; laser group (LG) 1 [LLLT 1] and control group (CG) 1 [control 1]) and day 17 (n = 8) (the end of the retention period; LG 2 [LLLT 2] and CG 2 [control 2]) for histological assessment. RESULTS: The LLLT 1 group had significantly higher numbers of osteoclasts than did the control 1 group (P = 0.036). No significant between-group difference in osteoblast cell or capillary numbers was evident when day 7 and 17 data were compared. CONCLUSION: Histologically, LLLT stimulated bone formation, as revealed by analysis after the retention period. LLLT during expansion may accelerate bone healing.

Effect of super short pulse Er:YAG laser on human dentin--Scanning electron microscopy analysis.

This study evaluated the effect of different pulse widths in the morphological characteristics of human dentin irradiated with Er:YAG in cavity preparation protocols and dentin pretreatment. Dentin discs with 2 mm thickness were obtained from 18 human molars. The experimental groups were composed from two variables: (1) clinical protocol-cavity preparation (E = 200 mJ/20 Hz)-and pretreatment (E = 80 mJ/2 Hz); and (2) pulse duration-50, 300, and 600 µs. This formed six experimental groups (n = 3): G1 (E = 200 mJ/20 Hz/50 µs); G2 (E = 200 mJ/20 Hz/300 µs); G3 (E = 200 mJ/20 Hz/600 µs); G4 (E = 80 mJ/2 Hz/50 µs); G5 (E = 80 mJ/2 Hz/300 µs); G6 (E = 80 mJ/2 Hz/600 µs). The samples were irradiated with the Er:YAG laser by noncontact mode at a focal distance of 7 mm from the target point under continuous water spray (60% water and 40% air). After the irradiation, they were processed for scanning electron microscopy (SEM). Morphological analysis showed an irregular dentin surface, absence of smear layer with opening of the exposure of dentinal tubules and protruding peritubular dentin-without indications of changes for all protocols used. Regardless of the analyzed experimental group, the dentin surface showed a microretentive morphology characteristic of ablation. The G1 and G4 showed a rougher surface when compared to other groups. Finally, we concluded that the pulse width can influence the morphological characteristics of the irradiated dentin tested in different clinical indications. The larger surface irregularity caused by regulation with less pulse width (50 µs) seems more appropriate to get a microretentive pattern necessary for successful adhesives restoration procedures.

The influence of low-level laser on orthodontic relapse in rats.

SUMMARY OBJECTIVES: This study evaluated the effect of low-level laser therapy (LLLT) on the tendency of rat molars to relapse following orthodontic tooth movement (OTM). MATERIAL AND METHODS: Maxillary rat molars were moved mesially for 10 days. Animals were randomly assigned to group I (non-irradiated) or II (irradiation with LLLT). Appliances were removed, and the molars allowed to relapse for 1, 3, 5, 7, 14, or 21 days; rats in group II received LLLT according to a protocol. Bone density of periapical alveolar bone was measured using radiographs and Digora software. Dental supporting structures were examined histologically with haematoxylin and eosin and tartrate-resistant acid phosphatase. RESULTS: In both groups, first molar relapse was rapid 1 day after the end of active treatment; by 21 days percentage relapse was measured as 86.11 per cent in group I, and 72.22 per cent in group II. Osteoclast number was highest at the end of active OTM, and thereafter successively decreased during the relapse phase in both groups. Decrease in number, and redistribution of osteoclasts occurred more rapidly in the non-irradiated than the LLLT group. Whilst molar relapse was generally less and osteoclast numbers generally higher in group II compared to group I, the differences were not significant. There was no significant difference in bone density between the two groups. CONCLUSIONS: These results indicate that LLLT may reduce the relapse tendency, possibly due in part to bone formation in previous tension areas, and to redistribution of osteoclasts following removal of orthodontic force. The role of LLLT in the prevention of orthodontic relapse requires further study.

Effectiveness of the diode laser in the treatment of ligature-induced periodontitis in rats: a histopathological, histometric, and immunohistochemical study.

The aim of this study was to evaluate the effects of the use of a high-power gallium-aluminum-arsenide diode laser (GaAlAs; 808 nm, 1 W, 20 s, 20 Hz, 10 J) alone or as adjunctive therapy to scaling and root planing in the treatment of induced periodontitis in rats. Periodontitis was induced by placing a ligature around the mandibular first molar of 60 rats. After 7 days, the ligature was removed and the animals were divided into four groups as follows: C (control), no periodontal treatment; SRP, scaling and root planing (SRP); DL, diode laser (DL) irradiation treatment; and SRP/DL, both SRP and DL irradiation treatment. Five animals from each group were euthanized at 7, 15, and 30 days posttreatment. The effectiveness of the treatments was evaluated in the furcation area using histopathological analysis, histometric analysis of alveolar bone loss (ABL), and immunohistochemical detection of tartrate-resistant acid phosphatase (TRAP), runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN). DL, alone or in combination with adjunctive therapy to SRP in the treatment of experimental periodontitis, resulted in a decreased local inflammatory response. At 7-days posttreatment, the DL and SRP/DL groups had fewer TRAP-positive cells and more RUNX2-positive cells. There was greater OCN immunolabeling in the DL group than in the C and SRP groups at 15 days. There was less ABL in the DL and SRP/DL groups at 15 and 30 days. In conclusion, DL was effective in the treatment of ligature-induced periodontitis in rats, both when used alone and when used as adjunctive therapy to SRP.

Low-level laser therapy as an alternative for pulpotomy in human primary teeth.

This study aimed to evaluate the effects of low-level laser therapy (LLLT) on pulpal response of primary teeth. Twenty mandibular primary molars were randomly divided into the following groups: group I Buckley's formocresol (diluted at 1:5), group II calcium hydroxide, group III LLLT + zinc oxide/eugenol, and group IV LLLT + calcium hydroxide. LLLT parameters were set at 660-nm wavelength, 10-mW power output, and 2.5 J/cm(2) energy density for 10 s in continuous mode (InGaAlP laser, Twin Laser®, MMOptics, Sao Carlos, Sao Paulo, Brazil). The teeth were extracted at the regular exfoliation period. The dentin-pulp complex was graded by an established histopathological score system. Statistical analysis was performed by Kruskal-Wallis and chi-square test. The histopathological assessment revealed statistically significant differences among groups (P < 0.05). The lowest degree of pulpal inflammation was present in LLLT + calcium hydroxide (P = 0.0296). Calcium hydroxide showed the highest rate of hard tissue barrier (P = 0.0033), odontoblastic layer (P = 0.0033), and dense collagen fibers (P = 0.0095). On the other hand, formocresol showed the highest incidence of internal resorption (P = 0.0142). Based on this study, low-level laser therapy preceding the use of calcium hydroxide exhibited satisfactory results on pulp tissue healing. However, further clinical studies on human teeth with long-term follow-up are needed to test the low-level laser therapy efficacy.

Functional approach to a Class II patient with upper first molar impaction.

The lack of the left first molar maxillary and the left second molar maxillary, caused respectively by impaction and agenesis is a very rare case, which determines an important occlusal imbalance and asymmetrical mandible movement. A gnatologic and functional orthodontic approach were planned to improve the retrognathic mandible and the muscular activity using kinesiograph and electromyography.

The effects of CO2 laser with or without nanohydroxyapatite paste in the occlusion of dentinal tubules.

The aim of this study was to evaluate a new treatment modality for the occlusion of dentinal tubules (DTs) via the combination of 10.6 µm carbon dioxide (CO2) laser and nanoparticle hydroxyapatite paste (n-HAp). Forty-six sound human molars were used in the current experiment. Ten of the molars were used to assess the temperature elevation during lasing. Thirty were evaluated for dentinal permeability test, subdivided into 3 groups: the control group (C), laser only (L-), and laser plus n-HAp (L+). Six samples, two per group, were used for surface and cross section morphology, evaluated through scanning electron microscope (SEM). The temperature measurement results showed that the maximum temperature increase was 3.2 °C. Morphologically groups (L-) and (L+) presented narrower DTs, and almost a complete occlusion of the dentinal tubules for group (L+) was found. The Kruskal-Wallis nonparametric test for permeability test data showed statistical differences between the groups (P < 0.05). For intergroup comparison all groups were statistically different from each other, with group (L+) showing significant less dye penetration than the control group. We concluded that CO2 laser in moderate power density combined with n-HAp seems to be a good treatment modality for reducing the permeability of dentin.

Brief communication: Comparative patterns of enamel thickness topography and oblique molar wear in two Early Neolithic and medieval population samples.

Enamel thickness has been linked to functional aspects of masticatory biomechanics and has been demonstrated to be an evolutionary plastic trait, selectively responsive to dietary changes, wear and tooth fracture. European Late Paleolithic and Mesolithic hunter-gatherers mainly show a flat wear pattern, while oblique molar wear has been reported as characteristic of Neolithic agriculturalists. We investigate the relationships between enamel thickness distribution and molar wear pattern in two Neolithic and medieval populations. Under the assumption that dietary and/or non-dietary constraints result in directional selective pressure leading to variations in enamel thickness, we test the hypothesis that these two populations will exhibit significant differences in wear and enamel thickness patterns. Occlusal wear patterns were scored in upper permanent second molars (UM2) of 64 Neolithic and 311 medieval subadult and adult individuals. Enamel thickness was evaluated by microtomography in subsamples of 17 Neolithic and 25 medieval individuals. Eight variables describing enamel thickness were assessed. The results show that oblique molar wear is dominant in the Neolithic sample (87%), while oblique wear affects only a minority (42%) of the medieval sample. Moreover, in the Neolithic molars, where buccolingually directed oblique wear is dominant and greatest enamel lost occurs in the distolingual quadrant, thickest enamel is found where occlusal stresses are the most important-on the distolingual cusp. These results reveal a correlation between molar wear pattern and enamel thickness that has been associated to dietary changes. In particular, relatively thicker molar enamel may have evolved as a plastic response to resist wear.