Addition of bone morphogenetic protein type 2 to ascorbate and β-glycerophosphate supplementation did not enhance osteogenic differentiation of human adipose-derived stem cells

Bone morphogenetic protein type 2 (BMP-2) is a potent local factor, which promotes bone formation and has been used as an osteogenic supplement for mesenchymal stem cells.

Objectives

This study evaluated the effect of a recombinant BMP-2 as well as the endogenous BMP-4 and BMP-7 in the osteogenic differentiation of adipose-derived stem cells (ASCs) in medium supplemented with ascorbate and β-glycerophosphate.

Material and Methods

Human ASCs were treated with osteogenic medium in the presence (ASCs+OM+BMP-2) or absence (ASCs+OM) of BMP-2. The alkaline phosphatase (ALP) activity was determined and the extracellular matrix mineralization was evaluated by Von Kossa staining and calcium quantification. The expressions of BMP-4, BMP-7, Smad1, Smad4, and phosphorylated Smad1/5/8 were analyzed by western blotting. Relative mRNA expressions of Smad1, BMP receptor type II (BMPR-II), osteonectin, and osteocalcin were evaluated by qPCR. Results: ASCs+OM demonstrated the highest expression of BMP-4 and BMP-7 at days 21 and 7, respectively, the highest levels of BMPR-II mRNA expression at day 28, and the highest levels of Smad1 mRNA at days 14 and 28. ASCs+OM+BMP-2 demonstrated the highest levels of Smad1 mRNA expression at days 1, 7, and 21, the highest expression of Smad1 at day 7, the highest expression of Smad4 at day 14, the highest ALP activity at days 14 and 21, and expression of phosphorylated Smad1/5/8 at day 7. ASCs+OM and ASCs+OM+BMP2 showed similar ALP activity at days 7 and 28, similar osteonectin and osteocalcin mRNA expression at all time periods, and similar calcium depositions at all time periods.

Conclusions

We concluded that human ASCs expressed endogenous BMP-4 and BMP-7. Moreover, the supplementation of ASCs with BMP-2 did not increase the level of osteogenic markers in the initial (ALP activity), intermediate (osteonectin and osteocalcin), or final (calcium deposition) phases, suggesting that the exogenous addition of BMP-2 did not improve the in vitro osteogenesis process of human ASCs.     

A survey of oral surgeons’ tobacco-use-related knowledge and intervention behaviors

Objectives: To evaluate whether oral surgeons are aware of tobacco’s role in oral health. Moreover, we wanted to know professionals’ attitudes towards smoker patients and physicians’ involvement in detecting and eradicating this habit in patients. Study Design: We conducted a survey to determine the awareness of the members of the Spanish Society of Oral Surgery about tobacco’s damage on oral health and the role of dentists in the prevention and elimination of the smoking habit. Results: 450 surveys were distributed during the Seventh National Congress of the Spanish Society of Oral Surgery, of which 224 (49.8%) were answered. Seventy-six point eight percent of oral surgeons said that they have a good knowledge of the effects of snuff on oral health. However, only 42.9% admitted they had received specific training regarding how to deal with patients who want to give up smoking. Sixty-three point four percent had explained to smoker patients the risk of this habit for the oral and general health. However, 17% admitted they do not advise their patients to give up smoking for fear of upsetting them, while 15.2% expressed lack of time, and 3.6% think it is not their competence. As to the relationship between oral cancer and smoking, 83% of oral surgeons recognize a direct relationship. In addition, 85.7% of professionals believe that dentists have a primary role in oral cancer prevention. Conclusions: These results indicate that most oral surgeons are concerned about the smoking habit of their patients. However, it is necessary to increase the specific training of dentists by providing tobacco treatment programs as part of their professional responsibility. Oral surgeons recognize the direct relationship between the smoking habit and oral cancer and regard as very important the role of dentists in the prevention of this disease. Key words:Smoking habit, oral surgery, oral cancer.     

Synthesis and cytotoxicity evaluation of granular magnesium substituted β-tricalcium phosphate

Objective:

The aim of this study was to produce dense granules of tricalcium phosphate (β-TCP) and magnesium (Mg) substituted β-TCP, also known as β-TCMP (Mg/Ca=0.15 mol), in order to evaluate the impact of Mg incorporation on the physicochemical parameters and in vitro biocompatibility of this novel material.

Material and Methods:

The materials were characterized using X-ray diffraction (XRD), infrared spectroscopy (FTIR), electron microscopy and inductively coupled plasma (ICP). Biocompatibility was assayed according to ISO 10993-12:2007 and 7405:2008, by two different tests of cell survival and integrity (XTT and CVDE).

Results:

The XRD profile presented the main peaks of β-TCP (JCPDS 090169) and β-TCMP (JCPDS 130404). The characteristic absorption bands of TCP were also identified by FTIR. The ICP results of β-TCMP granules extract showed a precipitation of calcium and release of Mg into the culture medium. Regarding the cytotoxicity assays, β-TCMP dense granules did not significantly affect the mitochondrial activity and relative cell density in relation to β-TCP dense granules, despite the release of Mg from granules into the cell culture medium.

Conclusion:

β-TCMP granules were successfully produced and were able to release Mg into media without cytotoxicity, indicating the suitability of this promising material for further biological studies on its adequacy for bone therapy.     

Value of videoroscopy in the detection of alterations of? Actinic Cheilitis?and the selection of biopsy areas

Background

To demonstrate the value of videoroscopy in identifying lesions and alterations not seen by oroscopy and to select the area for biopsy.

Material and Methods

Eighty patients were subjected to anamnesis, physical exam, videoroscopy exam, toluidine blue test and biopsy. A diagram of the lips was created to record the exact location where the lesion was found.

Results

Physical exam identified 287 lesions, and videoroscopy identified 587 lesions; erythema and white lesions were the most common lesions associated with actinic cheilitis. Of the 59 performed biopsies, 32 (52.4%) cases were identified by videoroscopy that showed lesions that were not detected during physical examination.

Conclusions

The establishment of a diagram of the lip permitted registration of the precise location of the lesion. Videoroscopy was effective in locating lesions not seen by oroscopy. Both videoroscopy and the diagram of the lips allowed for better and earlier diagnosis and better patient follow-up for those with actinic cheilitis. Key words: Actinic cheilitis, potentially malignant disorder, videoroscopy, dermatoscopy, lip. oroscopy, diagram of lip.     

Load-bearing capacity of screw-retained CAD/CAM-produced titanium implant frameworks (I-Bridge?2) before and after cyclic mechanical loading

Implant-supported screw-retained fixed dental prostheses (FDPs) produced by CAD/ CAM have been introduced in recent years for the rehabilitation of partial or total endentulous jaws. However, there is a lack of data about the long-term mechanical characteristics.

Objective

The aim of this study was to investigate the failure mode and the influence of extended cyclic mechanical loading on the load-bearing capacity of these frameworks.

Material and Methods

Ten five-unit FDP frameworks simulating a free-end situation in the mandibular jaw were manufactured according to the I-Bridge^®2-concept (I-Bridge^®2, Biomain AB, Helsingborg, Sweden) and each was screw-retained on three differently angulated Astra Tech implants (30º buccal angulation/0º angulation/30º lingual angulation). One half of the specimens was tested for static load-bearing capacity without any further treatment (control), whereas the other half underwent five million cycles of mechanical loading with 100 N as the upper load limit (test). All specimens were loaded until failure in a universal testing machine with an occlusal force applied at the pontics. Load-displacement curves were recorded and the failure mode was macro- and microscopically analyzed. The statistical analysis was performed using a t-test (p=0.05).

Results

All the specimens survived cyclic mechanical loading and no obvious failure could be observed. Due to the cyclic mechanical loading, the load-bearing capacity decreased from 8,496 N±196 N (control) to 7,592 N±901 N (test). The cyclic mechanical loading did not significantly influence the load-bearing capacity (p=0.060). The failure mode was almost identical in all specimens: large deformations of the framework at the implant connection area were obvious.

Conclusion

The load-bearing capacity of the I-Bridge^®2 frameworks is much higher than the clinically relevant occlusal forces, even with considerably angulated implants. However, the performance under functional loading in vivo depends on additional aspects. Further studies are needed to address these aspects.     

Clinicopathological evaluation of 164 dental follicles and dentigerous cysts with emphasis on the presence of odontogenic epithelium in the connective tissue. The hypothesis of “focal ameloblastoma”

Objectives: Some ameloblastomas presumably originate from odontogenic epithelium within the connective tissue of dental follicles and dentigerous cysts. Therefore, it would seem reasonable to discuss as whether odontogenic epithelium proliferations, frankly displaying ameloblastomatous features (“focal ameloblastoma”), should be considered as an “early” ameloblastoma. Study Design: Histopathological reports from 164 dental follicles and dentigerous cysts from the Department of Oral and Maxillofacial Surgery/Oral Pathology of the VU Free University medical center in Amsterdam, The Ne-therlands, were reviewed. Histopathological slides from 39 cases reporting the presence of odontogenic epithelium within the connective tissue were re-evaluated in order to assess the possible presence of focal ameloblastomas. Results: Focal ameloblastomas were detected in one dental follicle and in two dentigerous cysts. During a follow-up period of 6, 8 and 22 years, respectively, no clinical signs of (recurrent) ameloblastoma have occurred in these patients. Conclusions: Focal ameloblastoma possibly represents the early stage of ameloblastoma development. Key words:Ameloblastoma, odontogenic epithelium, dentigerous cyst, dental follicle.     

Does the number of implants have any relation with peri-implant disease?

Objective

The aim of this study was to evaluate the relationship between the number of pillar implants of implant-supported fixed prostheses and the prevalence of periimplant disease.

Material and Methods

Clinical and radiographic data were obtained for the evaluation. The sample consisted of 32 patients with implant-supported fixed prostheses in function for at least one year. A total of 161 implants were evaluated. Two groups were formed according to the number of implants: G1) ≤5 implants and G2) >5 implants. Data collection included modified plaque index (MPi), bleeding on probing (BOP), probing depth (PD), width of keratinized mucosa (KM) and radiographic bone loss (BL). Clinical and radiographic data were grouped for each implant in order to conduct the diagnosis of mucositis or peri-implantitis.

Results

Clinical parameters were compared between groups using Student''s t test for numeric variables (KM, PD and BL) and Mann-Whitney test for categorical variables (MPi and BOP). KM and BL showed statistically significant differences between both groups (p<0.001). Implants from G1 – 19 (20.43%) – compared with G2 – 26 (38.24%) – showed statistically significant differences regarding the prevalence of peri-implantitis (p=0.0210).

Conclusion

It seems that more than 5 implants in total fixed rehabilitations increase bone loss and consequently the prevalence of implants with periimplantitis. Notwithstanding, the number of implants does not have any influence on the prevalence of mucositis.     

Exploring the concept of “inflammatory angiogenesis” in keratocystic odontogenic tumor

Objective: The aim of the present study was to investigate the role of inflammation in angiogenesis of keratocystic odontogenic tumor (KCOT). Study Design: Twenty inflamed and 20 non-inflamed KCOTs were selected based on quantitative scoring of inflammation which was also applied on 20 radicular cysts. Microvessel density was assessed in all samples using CD34 antibody and angiogenesis was compared between the three groups. Statistical analysis was performed using one-way analysis of variance followed by post-hoc Scheffe test and P values less than 0.05 were considered significant. Results: A statistically significant difference in angiogenesis was found between radicular cysts and both inflamed and non-inflamed KCOTs (P < 0.001), but not between inflamed and non-inflamed KCOTs (P =0.347). Conclusion: Based on the results obtained in the present study, it seems that the effect of inflammation on angiogenesis in KCOT is minimal. However further investigation using other methods of evaluation is suggested to fully clarify the role of “inflammatory angiogenesis” in this neoplasm. Key words:Keratocystic odontogenic tumor, radicular cyst, angiogenesis, inflammation.     

Does non-surgical periodontal treatment influence on rheumatoid arthritis? A systematic review and meta-analysis

ObjectiveThe objective of this systematic review was to evaluate the efficacy of non-surgical periodontal therapy on rheumatoid arthritis activity.Material and methodsArticles published until April 2019 were electronically searched and screened using PubMed / MEDLINE, Scopus, and Cochrane databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA). This study was recorded in the international PROSPERO database (CRD42019132205). The PICO question (population, intervention, comparison, results) was: in adult patients with rheumatoid arthritis and periodontitis (P), does non-surgical periodontal treatment (I), as compared to no treatment (C), provides better outcomes in rheumatoid arthritis activity (O).ResultsAfter searching the databases, seven articles were selected for qualitative and five for quantitative analysis. The total number of participants included was 292, with an average age of 50.5 years. All patients had rheumatoid arthritis and periodontal disease. Non-surgical periodontal treatment significantly reduced Disease Activity Score 28 (P = 0.004; I² = 92%) and erythrocyte sedimentation rate (P = 0.01; I² = 78%), but with no significant effect on C-reactive protein (P = 0.34; I² = 92%).ConclusionsIt can be concluded that non-surgical periodontal treatment can benefit patients with rheumatoid arthritis.     

Developmental tendencies of the sagittal tooth axis between 10-13 years of age and the end of life; impact on retention?

In this study, 854 lateral cephalograms of normal toothed subjects from 10 to 87 years old who had no orthodontic treatment are analyzed. The posterior angles established by molars and sagitally examined maxillo-mandibular incisor-canine groups during occlusion are measured with age. These modifications are quantified in a general manner and then depending on facial typology.     

What do measures of ‘oral health‐related quality of life’ measure?

The terms 'health-related quality of life' and 'quality of life' are now in common use to describe the outcomes of oral health conditions and therapy for those conditions. In addition, there has been a proliferation of measures designed to quantify those outcomes. These measures, which were initially designated as socio-dental indicators or subjective oral health indicators are now more usually referred to as measures of oral health-related quality of life (OH-QoL). This is based on the assumption that the functional and psychosocial impacts they document must, of necessity, affect the quality of life. While this assumption has been subject to critical scrutiny in medicine, this is not the case with dentistry. Consequently, exactly what is being measured by indexes of OH-QoL is somewhat unclear. Based on the debate between Gill and Feinstein and Guyatt and Cook, we outline a number of criteria by means of which the construct addressed by measures of OH-QoL may be assessed. These are concerned with how the measures were developed and validated. These criteria are then used to appraise five of the many measures that have been developed over the past 20 years--the GOHAI, OHIP, OIDP, COHQoL and OH-QoL. The main conclusion is that while all document the frequency of the functional and psychosocial impacts that emanate from oral disorders they do not unequivocally establish the meaning and significance of those impacts. Consequently, the claim that oral disorders affect the quality of life has yet to be clearly demonstrated. Verifying this claim requires further qualitative studies of the outcomes of oral disorders as perceived by patients and persons, and the concurrent use of measures that more explicitly address the issue of quality of life.     

Do Implant Length and Width Matter for Short Dental Implants (<10 mm)? A Meta‐Analysis of Prospective Studies

Background: This meta‐analysis of prospective clinical trials was conducted to determine the effects of dental implant length and width on implant survival rate of short (<10 mm) implants. Methods: An electronic search of the PubMed database for relevant studies published in English from November 1998 to March 2012 was performed. Selected studies were randomized clinical trials, human clinical trials, or prospective trials with a clear aim of investigating the success or survival rate of short (<10 mm) implants. Results: Eight studies fulfilled the inclusion criteria and were subsequently analyzed. A total of 525 short (<10 mm) dental implants were analyzed, of which 253 were 3.5 mm in diameter (48.19%), 151 were 4.0 mm (28.76%), 90 were 4.1 mm (17.14%), 21 were 4.8 mm (4%), and 10 were 5.1 mm (1.9%). All implants included in this meta‐analysis had a follow‐up period of 12 to 72 months. The included studies reported on the survival rate and diameter of the implants. Six of the studies used “short implants” (7 to 9 mm), and the remaining were classified as “extra‐short implants” (≤6 mm). Five‐year estimated failure rates were 1.61% and 2.92%, respectively, for extra‐short and short implants (z = ?3.49, P <0.001, 95% confidence interval = 0.51% to 4.10%). Furthermore, it was found that the wider the implant, the higher the failure rate (estimated failure rate = 2.36%, 95% confidence interval = 1.07% to 5.23%). Conclusions: Neither implant length nor width seemed to significantly affect the survival rate of short implants (<10 mm). Nonetheless, further well‐designed randomized clinical trials are needed to confirm these findings.     

Does self‐weighting of items enhance the performance of an oral health‐related quality of life questionnaire?

OBJECTIVES: To determine if self-weighting of the items in an oral health-related quality of life questionnaire improves its psychometric properties. METHODS: The Surgical Orthodontic Outcome Questionnaire (SOOQ) was designed to assess the oral health-related quality of life of individuals before and after corrective surgery. Each of its 33 'items' consists of two questions: a question concerning the frequency with which a given functional or psychosocial problem had been experienced and a 'weighting' question which asked about how much the individual was bothered by that problem. The questionnaire was completed by three groups of individuals: (i) pretreatment; (ii) immediate (i.e. 2-6 months) postsurgery and (iii) postsurgery (i.e. more than 2 years after surgery). Unweighted scale scores were obtained by summing the response codes to the frequency question and weighted scores by summing the products of the frequency and bother questions. These scores were calculated for the full questionnaire and a short form consisting of 15 items. The discriminative and correlational construct validity of these scores was compared along with internal consistency reliability. The sensitivity to change and longitudinal construct validity of unweighted and weighted scores was assessed in a simulated evaluative study in which pretreatment and postsurgery subjects were paired. RESULTS: For both the long and short forms of the questionnaire, unweighted and weighted scores discriminated between the groups enrolled in the study. Correlations with a general health rating were similar, as were Cronbach's alpha values and test-retest reliabilities. The simulated evaluative study suggested no differences in sensitivity to change or longitudinal construct validity. When subscale scores were examined, there was a suggestion that weighting improved their reliability. CONCLUSIONS: Self-weighting of items did not substantially improve the performance of the SOOQ. Domain weights should be developed and tested to determine if they have an effect on its properties.     

Assessment of Osstell ISQ’s reliability for implant stability measurement: A cross-sectional clinical study

Resonance frequency analysis (RFA) allows assess implant stability by measuring implant oscillation frequency on the bone. RFA is an objective and non-invasive method for implant stability measurement, although scarce evidence has been provided so far on its reliability. Objectives: Assess the Osstell ISQ system’s reliability (i.e., its measurement reproducibility and repeatability) by means of the intraclass correlation coefficient (ICC) as statistical method. Study Desing: Implants stability registers were completed by means of Osstell ISQ on 85 implants on 23 patients. Six measurements were completed on each implant by means of two different SmartPegs (types I and II); that is, three consecutive measurements with each transducer. Results: Average ISQ was 72.40, 72.22 and 72.79, and 72.06, 72.59 and 72.82 in the first, second, and third measurements with SmartPegs I and II, respectively. Equal values or differences below three ISQ points were observed in 52.9% and 62.4% of the cases with SmartPegs I and II, respectively. The intraclass correlation coefficient was 0.97 for both SmartPegs, and repeatability and reproducibility also reached 0.97 for both SmartPegs. Conclusions: The RFA system Osstell ISQ presents almost perfect repeatability and reproducibility after intraclass correlation coefficient analysis. Osstell ISQ measurements are highly reliable regarding reproducibility. Therefore, one measurement proves enough. Key words:Dental implants, RFA, ISQ, implant stability, Osstell.     

Increased nuclear ?-catenin expression in oral potentially malignant lesions: A marker of epithelial dysplasia

Background

Deregulation of ?-catenin is associated with malignant transformation; however, its relationship with potentially malignant and malignant oral processes is not fully understood. The aim of this study was to determine and compare the nuclear ?-catenin expression in oral dysplasia and oral squamous cell carcinoma (OSCC).

Material and Methods

Cross sectional study. Immunodetection of ?-catenin was performed on 72 samples, with the following distribution: 21 mild dysplasia, 12 moderate dysplasia, severe dysplasia 3, 36 OSCC including 19 well differentiated, 15 moderately differentiated and 2 poorly differentiated. Through microscopic observation the number of positive cells per 1000 epithelial cells was counted. For the statistical analysis, the Kruskal Wallis test was used.

Results

Nuclear expression of ?-catenin was observed in all samples with severe and moderate dysplasia, with a median of 267.5, in comparison to mild dysplasia whose median was 103.75. Only 10 samples (27.7%) with OSCC showed nuclear expression, with statistically significant differences between groups (p < 0.05).

Conclusions

Our results are consistent with most of the reports which show increased presence of ?-catenin in severe and moderate dysplasia compared to mild dysplasia; however the expression of nuclear ?-catenin decreased after starting the invasive neoplastic process. This suggests a role for this protein in the progression of dysplasia and early malignant transformation to OSCC. Immunodetection of ?-catenin could be a possible immune marker in the detection of oral dysplasia. Key words:Oral squamous cell carcinoma (OSCC), ?-catenin, oral dysplasia.     

Impact of?crestal and subcrestal implant placement in peri-implant bone: A prospective comparative study

Background

To assess the influence of the crestal or subcrestal placement of implants upon peri-implant bone loss over 12 months of follow-up.

Material and Methods

Twenty-six patients with a single hopeless tooth were recruited in the Oral Surgery Unit (Valencia University, Valencia, Spain). The patients were randomized into two treatment groups: group A (implants placed at crestal level) or group B (implants placed at subcrestal level). Control visits were conducted by a trained clinician at the time of implant placement and 12 months after loading. A previously established standard protocol was used to compile general data on all patients (sex and age, implant length and diameter, and brushing frequency). Implant success rate, peri-implant bone loss and the treatment of the exposed implant surface were studied. The level of statistical significance was defined as 5% (α=0.05).

Results

Twenty-three patients (8 males and 15 females, mean age 49.8±11.6 years, range 28-75 years) were included in the final data analyses, while three were excluded. All the included subjects were nonsmokers with a brushing frequency of up to twice a day in 85.7% of the cases. The 23 implants comprised 10 crestal implants and 13 subcrestal implants. After implant placement, the mean bone position with respect to the implant platform in group A was 0.0 mm versus 2.16±0.88 mm in group B. After 12 months of follow-up, the mean bone positions were -0.06±1.11 mm and 0.95±1.50 mm, respectively - this representing a bone loss of 0.06±1.11 mm in the case of the crestal implants and of 1.22±1.06 mm in the case of the subcrestal implants (p=0.014). Four crestal implants and 5 subcrestal implants presented peri-implant bone levels below the platform, leaving a mean exposed treated surface of 1.13 mm and 0.57 mm, respectively. The implant osseointegration success rate at 12 months was 100% in both groups.

Conclusions

Within the limitations of this study, bone loss was found to be greater in the case of the subcrestal implants, though from the clinical perspective these implants presented bone levels above the implant platform after 12 months of follow-up. Key words:Immediate implants, tooth extraction, dental implants, single-tooth, crestal bone, placement level.     

Durability of Digora Optime<Superscript>®</Superscript> imaging plates

Objectives

To assess the durability of the imaging plates (IP) supplied with the Digora Optime^® digital imaging system in terms of their functionality after as many as 1000 exposures and the degree of signal fading that occurred after a delay of up to 144 h between exposure and scanning

Methods

The materials examined consisted of eight IPs. Three new and three used IPs were tested for signal fading, and the other two new IPs were exposed 1000 times and then tested for durability. The first exposure image data were used as baseline for comparison. The exposed IPs were then scanned 0, 5, 10, 30, and 60 min, and 3, 24, 72, and 144 h after exposure. Images without automatic gain control were used in both analyses. These images were exported as 24-bit tiff files with 8-bit gray value data, and mean gray values (MGVs) were measured and compared. Image gray value (IGV) in each image was calculated for statistical analysis. Immediately scanned pixel data were used as baseline for comparison. Statistical analysis was performed by ANOVA and use of Dunnett’s multiple comparison test (P < 0.05).

Results

There were no significant differences for up to 1000 exposures, and no significant difference was observed among images scanned with a delay of up to 3 h in new and used IPs. There was no significant difference between new and used IPs.

     

Immunoexpression of α2-integrin and Hsp47 in hereditary gingival fibromatosis and gingival fibromatosis-associated dental abnormalities

Objective: The purpose of the present study was to investigate the expression of the α2-integrin subunit and heat shock protein 47 (Hsp47) in two families with isolated gingival fibromatosis (GF) form and one family with GF associated with dental abnormalities and normal gingiva (NG). Study Design: Immunohistochemistry was performed with antibodies against α2-integrin and Hsp47 in specimens from two unrelated families with hereditary gingival fibromatosis (Families 1 and 2) and from one family with a gingival fibromatosis-associated dental abnormality (Family 3); NG samples were used for comparison. The results were analysed statistically. Results: Immunoreactivity for α2-integrin and Hsp47 was observed in the nucleus of epithelial cells of both the basal and suprabasal layer and a more discreet signal was noted in connective tissue in all study samples. Hsp47 showed higher immunoreactivity in Family 2 compared with the other families (p≤0.05). Despite the markup α2-integrin was higher in Family 3 there was no statistically significant difference between the families studied (p≥0.05). Conclusions: Our results confirmed the heterogeneity of GF, such that similar patterns of expression of the condition may show differences in the expression of proteins such as Hsp47. Although no difference in α2-integrin expression was observed between GF and NG groups, future studies are necessary to determine the exact role of this protein in the various forms of GF and whether it contributes to GF pathogenesis. Key words:Gingival fibromatosis, integrin alpha2, heat shock protein Hsp47.     

Dental caries in Mexican schoolchildren: A comparison of 1988–1989 and 1998–2001 surveys

Objectives: To compare two surveys across seven states for the prevalence of dental caries among Mexican schoolchildren. Study Design: Analysis of two cross-sectional surveys: Schoolchildren from 6 to 10 years of age were examined in the 1988–1989 survey and 6- to 10-year-old and 12-year-old students were included in the 1998–2001 survey. The baseline data of seven states were available for analysis. Representative probability samples were conducted statewide in both surveys. The World Health Organization (WHO) method was used to obtain the dental caries index (dmft, DMFT). At present, additional and more recent epidemiological data representative statewide in Mexico are unavailable. Results: The participants were 9798 schoolchildren in the 1988–1989 survey and 16882 schoolchildren in the 1998–2001 survey. The prevalence of caries in children ages 6 to 10 years was 86,6% in the first survey and 65,5% in the second survey, showing a 24,4% reduction. The primary teeth index in the first survey was dmft = 3,86 (IC95% 3,68 4,04) and in permanent teeth, it was DMFT = 1,03 (IC95% 0,95 1,11). In the second survey, the comparable values were dmft = 2,36 (IC95% 2,20 2,52) and DMFT = 0,35 (IC95% 0,29 0,40), corresponding to a reduction of 38,89% and 66,02% in the primary and permanent dentition, respectively. Treatment needs remain high: In the second survey, as 92,75% of the index DMFT was conformed as decayed teeth. Conclusion: Overall, we detected a downward trend in the dental caries indices, particularly in the permanent dentition. The increase in the availability of fluoride likely contributed to the observed decline in dental caries. Key words:Schoolchildren, dental caries, treatment needs, salt fluoridation, Mexico.