Assessment of dental pulp response to carries via MR T2mapping and histological analysis.

OBJECTIVES: The aim of our study was to assess the correlation between T2 relaxation times and their variability with the histopathological results of the same teeth in relation to caries progression. MATERIALS AND METHODS: 52 extracted permanent premolars were included in the study. Prior to extractions, patients underwent magnetic resonance imaging (MRI) scanning and teeth were evaluated using ICDAS classification. Pulps of extracted teeth were histologically analysed. RESULTS: MRI T2 relaxation times (ms) were 111,9 ± 11.2 for ICDAS 0, 132.3 ± 18.5* for ICDAS 1, 124.6 ± 14.8 for ICDAS 2 and 112. 6 ± 18.2 for ICDAS 3 group (p = 0,013). A positive correlation was observed between MRI T2 relaxation times and macrophage and T lymphocyte density in healthy teeth. There was a positive correlation between vascular density and T2 relaxation times of dental pulp in teeth with ICDAS score 1. A negative correlation was found between T2 relaxation times and macrophage density. There was a positive correlation between T2 relaxation time variability and macrophage and T lymphocyte density in teeth with ICDAS score 2. In teeth with ICDAS score 3, a positive correlation between T2 relaxation times and T2 relaxation time variability and lymphocyte B density was found. CONCLUSION: The results of our study confirm the applicability of MRI in evaluation of the true condition of the pulp tissue. CLINICAL RELEVANCE: With the high correlation to histological validation, MRI method serves as a promising imaging implement in the field of general dentistry and endodontics.

Three-dimensional semi-automated volumetric assessment of the pulp space of teeth following regenerative dental procedures.

The volumetric change that occurs in the pulp space over time represents a critical measure when it comes to determining the secondary outcomes of regenerative endodontic procedures (REPs). However, to date, only a few studies have investigated the accuracy of the available domain-specialized medical imaging tools with regard to three-dimensional (3D) volumetric assessment. This study sought to compare the accuracy of two different artificial intelligence-based medical imaging programs namely OsiriX MD (v 9.0, Pixmeo SARL, Bernex Switzerland, https://www.osirix-viewer.com ) and 3D Slicer ( http://www.slicer.org ), in terms of estimating the volume of the pulp space following a REP. An Invitro assessment was performed to check the reliability and sensitivity of the two medical imaging programs in use. For the subsequent clinical application, pre- and post-procedure cone beam computed tomography scans of 35 immature permanent teeth with necrotic pulp and periradicular pathosis that had been treated with a cell-homing concept-based REP were processed using the two biomedical DICOM software programs (OsiriX MD and 3D Slicer). The volumetric changes in the teeth's pulp spaces were assessed using semi-automated techniques in both programs. The data were statistically analyzed using t-tests and paired t-tests (P = 0.05). The pulp space volumes measured using both programs revealed a statistically significant decrease in the pulp space volume following the REP (P < 0.05), with no significant difference being found between the two programs (P > 0.05). The mean decreases in the pulp space volumes measured using OsiriX MD and 3D Slicer were 25.06% ± 19.45% and 26.10% ± 18.90%, respectively. The open-source software (3D Slicer) was found to be as accurate as the commercially available software with regard to the volumetric assessment of the post-REP pulp space. This study was the first to demonstrate the step-by-step application of 3D Slicer, a user-friendly and easily accessible open-source multiplatform software program for the segmentation and volume estimation of the pulp spaces of teeth treated with REPs.

Oral health of 6-7 year-old children according to the Caries Assessment Spectrum and Treatment (CAST) index.

BACKGROUND: The index of Caries Assessment Spectrum and Treatment (CAST) reveals a range of caries development from a non-cavitated status to advanced lesions. The aim of the present study was to explore the oral health status of 6- to 7-year-old children based on the CAST index in relation to oral health knowledge and background determinants. METHODS: A multi-stage cluster random sampling method was applied and after ethical clearance, clinical examination was performed (Kappa = 0.89). The status of caries and oral hygiene was recorded according to the CAST index and OHI-Simplified (OHI-S) index, respectively. A self-administered questionnaire was used to collect the data of parental knowledge of oral health. SPSS version 22.0 was used for data analysis and p-value less than 0.05 were considered significant. RESULTS: Seven hundred and thirty-nine children and their parents in 24 schools participated in this study (88%), of whom 48.6% were boys and the rest were girls. In permanent molars, a healthy status (code 0-2) was observed in 89.3-93.7% of the teeth. In primary molar teeth, dentinal lesions ranged from 25.3 to 31.2%, the prevalence of pulp involvement was between 2.9 and 10.5%, and less than 1% had abscess/fistula. Serious morbidity (codes 6 and 7) were more common in the first primary molars than the second ones. Multi-variable logistic regression analysis indicated that children with a low level of father's education were 2.45 times more likely to have a CAST score of 3 and higher (95% CI 1.35-4.46, p = 0.003) compared to children whose fathers had academic education. For each one-unit increment of OHI_S, the likelihood of a CAST score 3 and higher in primary dentition increased by 1.77 times (OR = 1.77; 95% CI 1.08-2.93, p = 0.02). CONCLUSION: The consequences of dental caries including abscess and fistula were more prevalent in the first and second primary teeth. There was a significant correlation between a CAST score of 3 and higher with father's education (as an indicator of social rank) and oral hygiene status. The CAST index is a useful and practical index in epidemiological surveys.

Quantitative assessment of morphological changes of dental pulp components of teeth affected by occlusal trauma.

AIM: In the general economy of the stomatognathic system functionality, the occlusal function has an important role, meaning both the dental-dental reports and the dynamic reports interarch-interarch. Because of the interrelationships and inter-dependency that govern the functioning of the biological systems, a pathological change affecting a component of the stomatognathic system produces impaired functioning of the others. The aim of the present study is to assess the morphological changes occurred in the dental pulp components of teeth affected by occlusal trauma. MATERIALS AND METHODS: Fragments of dental pulp coming from 45 patients with occlusal trauma were processed using classical histological techniques (formalin fixation and paraffin embedment) and stained with Hematoxylin-Eosin (HE), Masson's trichrome and anti-CD34 antibody immunostaining, in order to highlight the peripheral zone and central connective tissue of dental pulp morphological changes. A set of parameters namely thickness of peripheral zone components, calcifications, fibrosis and vascular density in the dental pulp were assessed individually and based on three topographical criteria namely the affected tooth, the position on the dental arches and the position according to sagittal plane. RESULTS: There was no correlation between morphological changes of dental pulp and the topography of teeth with occlusal trauma. The size of the peripheral area of the dental pulp and that of its components evolved in the same sense, whether it was growth or decrease. Decrease of the peripheral area was associated with the increase of collagen fibers density, calcium deposits and density of the capillary network. The direct correlation between the amount of collagen fibers and vascular density seems somewhat paradoxical but it can be explained by the reemergence of chronic inflammatory events located in the dental pulp. CONCLUSIONS: It seems that dental pulp morphological changes are not influenced by the teeth with occlusal trauma topography. With one exception (the components of peripheral zone), most of the correlations between the dental pulp morphological changes were only suggested but not validated statistically, which requires further studies on larger groups together with the introduction of inflammatory cell population studies.

Caries Assessment Spectrum and Treatment (CAST) Index in the Primary Molars of 6- to 7-year-old Polish Children.

PURPOSE: To evaluate the caries prevalence and experience in primary molars in Polish 6- to 7-year-old children using the Caries Assessment Spectrum and Treatment index. MATERIALS AND METHODS: This cross-sectional study was carried out on a sample of 332 out of 468 invited children (140 6- and 192 7-year-olds). Cluster sampling was used to select the participating schools. Dental status was evaluated according to the criteria dedicated to CAST. The means of the individual CAST scores were assessed. Data were statistically analysed using the Mann-Whitney U-test (p < 0.05). The percentage of children according to the highest CAST score was calculated. The mean values of the dmft index, based on three different caries thresholds--CAST codes 3 to 7 (d3-7t), 4 to 7 (d4-7t) and 5 to 7 (d5-7t)--were calculated. RESULTS: The response rate was 70.9%. One-fifth of the participants showed a healthy, functional dentition (CAST codes 0-2). The highest percentage of children had at least one carious tooth with pulpal involvement (26.2%), followed by children having an obvious dentin caries lesion (20.8%). The means for CAST codes 3, 4 and 5 were 0.61 ± 1.0, 0.19 ± 0.53 and 1.23 ± 1.61, respectively. The means of molars with pulpal involvement was 0.83 ± 1.32 and with dental sepsis 0.07 ± 0.33. Apart from filled teeth, no age-dependent differences were observed. The d3-7mft, d4-7mft and d5-7mft were as follows: 5.18, 4.61 and 4.41, respectively. CONCLUSION: The surveyed Polish children showed high caries prevalence and severe caries experience in the primary molars. The CAST index was a useful tool for the epidemiological analysis of primary molars.

Histologic Assessment of Quick-Set and Mineral Trioxide Aggregate Pulpotomies in a Canine Model.

INTRODUCTION: Quick-Set (Primus Consulting, Bradenton, FL) is a calcium aluminosilicate cement that is a potential alternative to mineral trioxide aggregate (MTA) with greater acid resistance and faster setting. The purpose of this study was to compare the effects of Quick-Set and MTA on pulpal tissues in response to pulpotomy procedures. METHODS: The pulp chambers of 42 maxillary teeth in 7 beagle dogs were accessed, and the coronal pulpal tissue was removed. Pulpotomy procedures were performed, placing the experimental materials directly over the radicular pulp tissues. The dogs were sacrificed at 70 days, and the teeth and surrounding tissues were removed and prepared for histologic analysis. The sections of the pulpotomy areas were scored for inflammation, pulp tissue organization, reactionary dentin formation, and quality of dentinogenesis. RESULTS: The Quick-Set group exhibited significantly more pulpal inflammation (P = .002) and significantly less pulp tissue organization (P = .004). No significant difference was noted for reactionary dentin formation (P = .526) and quality of dentinogenesis (P = .436). CONCLUSIONS: Compared with ProRoot White MTA (Dentsply Tulsa Dental Specialties, Tulsa, OK), Quick-Set exhibited more pulpal inflammation and decreased pulp tissue organization. No significant differences were noted for reactionary dentin formation and quality of dentinogenesis.

The Caries Assessment Spectrum and Treatment (CAST) instrument: construct validation.

The Caries Assessment Spectrum and Treatment (CAST) is a newly developed epidemiological instrument. The aim of this study was to investigate its construct validity. Four calibrated examiners, using CAST codes 0-6, visually examined 109 surfaces of extracted and exfoliated teeth. These teeth were then hemisectioned, photographed, and assessed histologically by two calibrated examiners using the Downer criteria. Twenty-eight of the 109 teeth were scanned using micro-computed tomography (micro-CT) and assessed by the same examiners using the same criteria. Validation was determined through calculation of the sensitivity, specificity, and Youden index for two categories of carious lesions examined visually, with histology and micro-CT as gold standards. Interexaminer consistency was κ = 0.76: SE ± 0.05 between visual and histological assessments of teeth and was κ = 0.89: SE ± 0.08 between visual and micro-CT assessments. For the category 'healthy' vs. 'diseased' (CAST codes 0-2 vs. CAST codes 3-6), sensitivity, specificity, and Youden index values of 100%, 92.9%, and 93%, respectively, for micro-CT, and 96.6%, 86%, and 83%, respectively, for histology, were obtained. For the category 'dentine' vs. 'non-dentine lesions' (CAST codes 0-3 vs. CAST codes 4-6) sensitivity, specificity, and Youden index values of 90%, 100%, and 90%, respectively, for micro-CT, and 81.4%, 100%, and 81%, respectively, for histology, were obtained. Construct validity of the CAST instrument was obtained.

The caries assessment spectrum and treatment (CAST) instrument: its reproducibility in clinical studies.

A new caries assessment instrument, the Caries Assessment Spectrum and Treatment (CAST), was developed. It covers carious lesion progression from no lesion, sealants and restorations to lesions in enamel and dentine, advanced stages in pulpal and tooth-surrounding tissues, and tooth loss owing to dental caries, in nine codes. The objective of this study was to determine the reproducibility of the CAST instrument in primary and permanent dentitions, using three age groups. Two epidemiological surveys were conducted in Brazil, covering three age groups: 2-6-year-old and 6-9-year-old children and 19-30-year-old adults. Four trained and calibrated examiners performed the examinations. Reproducibility was calculated for intra- and inter-examiner at surface and tooth levels and expressed as unweighted kappa-coefficient value (κ) and percentage of agreement (Po) for CAST codes (0-7) and for the categories healthy (0-2) versus diseased (3-7), and non-cavitated (0-3) versus cavitated (4-7) teeth. Using CAST codes (0-7) for the 2-6-year-old age group in primary dentitions, inter-examiner consistency was κ = 0.74 and Po was 98.3%. In the 6-9-year-old age group in primary dentitions, inter-examiner consistency ranged from κ = 0.68 to κ = 0.86 and Po was ≥ 93.7%. In the 19-30-year-old age group inter-examiner consistency was κ = 0.87 and Po was 94.1%. The reproducibility of the CAST instrument for use in the primary dentition of 2-6-year olds and of 6-9-year olds was 'substantial' to 'almost perfect'. The reproducibility for its use in the permanent dentition of 19-30-year olds was 'almost perfect'. The CAST instrument can reliably be applied in epidemiological studies covering these ages.

Comparison of photographic and visual assessment of occlusal caries with histology as the reference standard.

BACKGROUND: The purpose of this study was to compare diagnostic performance for the detection of caries using photographs with an established visual examination method and histological sections as the reference standard. METHODS: 50 extracted permanent teeth were assessed for the presence of occlusal caries by 9 examiners using two methods; traditional visual examination developed by BASCD and photographs produced by an intra-oral camera. For both methods, diagnoses were made at "caries into dentine" level. The teeth were histologically sectioned and the diagnostic decisions using visual and photographic assessment were compared to the histological reference standard. Inter- and intra- examiner reliability for the methods was assessed and weighted kappa values were calculated. RESULTS: The visual examination method had a median sensitivity value of 65.6% and a median specificity value of 82.4%. The photographic assessments method had a median sensitivity of 81.3% and a median specificity of 82.4%. CONCLUSIONS: The photographic assessments method had a higher sensitivity for caries detection than the visual examination. The two methods had comparable specificities and good intra- and inter- examiner reliability.

Assessment of the dentin-pulp complex response to caries by ADC mapping.

The prognostic potential of apparent diffusion coefficient (ADC) mapping was studied as complemented by high-resolution 3D T(1)-weighted MRI in the assessment of dentin-pulp complex response to caries. Twenty-six extracted human teeth, with or without caries lesions of different grades in accord with the International Caries Detection and Assessment System (ICDAS), were analyzed by high-resolution MRI at 2.35 T. A signal rise in demineralized hard dental tissues in high-resolution T(1)-weighted MR images enabled assessment of the demineralization depth over the whole range of ICDAS scores. ADC maps of the teeth were calculated from corresponding diffusion-weighted images of four different b values: 0, 132, 317, 635 s/mm(2). These maps enabled reliable differentiation between intact (ADC > 1.0·10(-9) m(2)/s) and affected (ADC < 1.0·10(-9) m(2)/s) regions of dental pulp. Linear regression analyses of demineralization depth in relation to ICDAS score and then also to average ADC of dental pulp showed that a demineralization depth increase of one millimeter corresponds to an ICDAS score increase of 1.2 and an average ADC decrease of 0.07·10(-9) m(2)/s. Results of the study indicate that the average ADC value of dental pulp could be used as a potential marker to assess tissue response to caries comparable to that of ICDAS scoring.

Histologic assessment of human pulp response to capping with mineral trioxide aggregate and a novel endodontic cement.

INTRODUCTION: This study was conducted to compare human pulp response to mineral trioxide aggregate (MTA) and a novel endodontic cement (NEC) when used as pulp capping materials after a time period of 2 and 8 weeks. METHODS: Thirty-two premolar teeth that were scheduled for extraction for orthodontic reasons were exposed and capped with either MTA or NEC. Half of the specimens underwent extraction and histologic analysis after 2 weeks, and the remaining half were assessed after 8 weeks. Each slide was graded histologically according to the morphology of the dentinal bridge, thickness of the dentinal bridge, presence of odontoblast cells, and inflammation of the pulp. RESULTS: Both MTA and NEC showed significantly better pulp response after 8 weeks compared with 2 weeks, with a thicker and more tubular pattern of the dentinal bridge, less pulp inflammation, and a palisade pattern of odontoblast cells. Although MTA and NEC groups had no significant difference in each measure in both time intervals, NEC induced a thicker dentinal bridge with less pulp inflammation at both 2 weeks and 8 weeks, compared with MTA. CONCLUSIONS: MTA and NEC showed similar biocompatibility and favorable response in pulp capping treatment and inducing the formation of the dentinal bridge.

DIAGNOdent laser fluorescence assessment of endodontic infection.

INTRODUCTION: Real-time assessment of the microbial status of the root canal system would be useful in clinical endodontic practice for determining endpoints of biomechanical treatment. This laboratory study used an existing laser fluorescence device, the DIAGNOdent (KaVo, Biberach, Germany), in a proof-of-concept study. METHODS: Visible laser red light (wavelength 655 nm) was used to elicit fluorescence emissions in the near-infrared range from infected and uninfected root canals. A prototype sapphire tip designed for periodontal assessment was used to analyze the pulp chamber and coronal third of the root canal system in extracted teeth. The fluorescence properties of bacterial cultures, monospecies biofilms in root canals, pulpal soft tissues, and sound dentin were also evaluated, together with 50 extracted teeth with known endodontic pathology. RESULTS: Sound dentin and healthy pulpal soft tissue gave an average fluorescence reading of 5 (on a scale of 100), whereas biofilms of Enterococcus faecalis and Streptococcus mutans established in root canals showed a progressive increase in fluorescence over time. Fluorescence readings reduced to the "healthy" threshold reading of 5 when root canals were endodontically treated, and the experimentally created bacterial biofilms were removed completely. High fluorescence readings were recorded in the root canals and pulp chambers of extracted teeth with radiographic evidence of periapical pathology and scanning electron microscopy evidence of bacterial infection. CONCLUSIONS: The use of the DIAGNOdent fluorescence approach for the assessment of the status of the pulp chamber and root canal system holds promise for clinical application; once more, flexible tips can be developed for gaining greater penetration into middle and apical thirds of the root canal.

Histological assessment of pulp condition after apical vital root transection in one root of multirooted teeth in dogs: a preliminary study.

One of the most important aspects in surgery is the healing process after the periapical surgery. Past studies have shown occasional encounters with vital root resection and have noted varying degrees of pulpal response after root resection in periodontal disease. The purpose of this investigation was to observe the pulpal and periapical responses to intentional apical vital root transection in one root of multirooted teeth of German-Canadian dogs over a 6-month postoperative period. This is an experimental study performed on left maxillary and mandibular quadrants of four adult German-Canadian dogs after a 3- and 6-month period. Four teeth were assessed in each interval. One of the roots of multirooted teeth in the left quadrant of both maxillary and mandibular jaws was surgically transected. Tissue blocks were prepared by routine histological methods after 12 and 24 weeks after the surgery. The results showed a disruption of the normal pulpal architecture, with initial pulpal degeneration and subsequent early replacement by the periodontal ligament tissue after 24 weeks. Hypercementosis was seen around the apical portion of the root in all specimens. Pulpal regeneration was seen in the both upper and lower molars (p = 0.03). Resorption took place only in two specimens (p = 0.46). The inflammation in the 12th week was more than the 24th week. The pulp of multirooted teeth remains vital after transection of the apical part of the root in dogs. Longer follow-up periods are recommended because root canal therapy or extraction is indicated if resorption, necrosis, or ankylosis is seen.

Frecuencia de diagnósticos y tratamientos pulpares según indicadores de la demanda realizados en una clínica dental universitaria / Frequency of pulpar diagnostics and treatment by demand indicators in a college dental clinic

Los diagnósticos y tratamientos pulpares que fueron realizados en los pacientes del pregrado de la Clínica Estomatológica Central de la Facultad de Estomatología Roberto Beltrán Neira de la Universidad Peruana Cayetano Heredia durante el período 2003 al 2004, se relacionaron según los indicadores de la demanda. Se encontró que la mayor frecuencia de tratamientos pulpares fueron las pulpectomías anteriores (50,2 por ciento), seguidas de las pulpectomías en molares (24,8 por ciento) y por último las pulpectomías en premolares (24,7 por ciento). Los diagnósticos pulpares mas frecuentemente hallados correspondieron a pulpitis aguda (45,1 por ciento), pulpa vital (27,4 por ciento), encontrándose mayor tratamiento en el sexo femenino.

Assessment of dysplastic dentin in osteogenesis imperfecta and dentinogenesis imperfecta.

Two semiquantitative scoring systems, Clinical Radiographic Score (CRS) and Dysplastic Dentin Score (DDS), were introduced for analyzing degree of dysplastic manifestations in dentin. The utility of both systems was demonstrated in a large material of teeth from patients with dentinogenesis imperfecta (DI) and osteogenesis imperfecta (OI). Twenty teeth from healthy controls, 81 teeth from 40 patients with OI, and 18 teeth with DI without OI (DI type II) were examined. The degree of dysplasia was correlated with type and form of OI and type of DI. The median DDS did not differ between DI associated with OI (DI type I) and DI type II. DDS in OI patients without clinical signs of DI was above that of control teeth. Both circumpulpal and mantle dentin showed increased DDS, although circumpulpal dentin was more severely affected. The median DDS was highest for the most severe type of non-lethal OI (type III). DDS increased significantly with form (severity) of OI. A significant association between DDS and CRS was found, although diagnosis of DI in less severe cases was not possible based on radiographic or clinical signs alone. Thus, the DDS system proved valuable when the CRS system based on radiographic/clinical manifestations failed, the most significant finding being subclinical histological manifestations of DI in patients with OI but without clinical or radiographic signs of DI. These subtle dysplastic changes are most likely an expression of genetic disturbances associated with OI and should not be diagnosed as DI, but rather be termed histologic manifestations of dysplastic dentin associated with OI.

Multiple regression models for age estimation by assessment of morphologic dental changes according to teeth source.

The aims of this study were twofold: (1). to measure parameters that contribute significantly to estimates of dental age, using a combination of classic methods and a computer-assisted image analysis procedure to avoid the bias inherent in observer subjectivity; and (2). to develop new mathematical regression models for age prediction according to postmortem interval. Two different populations were studied. Forty-three permanent teeth (Group I), extracted for valid clinical reasons, were taken from patients 25-79 years of age. The other population group (Group II) was composed of 37 healthy erupted permanent teeth obtained from human skeletal remains (age 22-82 years) with a postmortem interval ranging from 21 to 37 years. Morphologic age-related changes were investigated by measuring variables on intact and half-sectioned teeth. Multiple regression analyses were performed with age as the dependent variable for each sample source. In fresh extracted teeth, the variables that made the greatest contributions to predictions of age were dental attrition, dentin color, and translucency width, the latter measured with a computer-assisted image analysis method. In teeth from human skeletal remains, the variables that made the greatest contributions to age calculation were cementum apposition, pulp length measured by computer-assisted image analysis, dental attrition, root translucency, and dental color. We conclude by recommending different regression models to calculate age depending on the postmortem interval.

A survey of pediatric dentists' management of dental caries in children three years of age or younger.

PURPOSE: The purpose of this investigation was to obtain information from practicing pediatric dentists about how they manage caries in children three years of age and younger and the problems they are encountering. METHODS: A survey mailed to a randomly selected sample of 1,000 members of the American Academy of Pediatric Dentists (AAPD) in January of 1997 asked them to: identify the types and extent of caries in the young age group; define and quantify methods used to manage caries; determine the representation of caries among different payer source groups; identify sources of information used in managing caries; and determine the criteria they use for assessing the success of different methods in managing caries. RESULTS: The response rate was 43%. Definitions of techniques of managing caries varied among practitioners, and the use of the methods differed for the different degrees of severity of caries. There was a significant relationship between the percentage of Medicaid in a practice and the percentage of children with caries and pulpal involvement. Personal experience/philosophy was most frequently identified as an important source among factors influencing treatment decisions and sources of information about managing. Criteria most frequently cited to determine effectiveness of treatment were "caries free at recall" (45%) and "stop progress of lesion" (30%). CONCLUSION: Practitioners use a variety of techniques to manage caries in the child < or = 3 years of age. Disease level and payer source factored heavily in their treatment decisions. Practitioners reported interest in receiving information and help from AAPD on the subject.

Review of bonded amalgam restorations, and assessment in a general practice over five years.

This study reviewed the literature on bonded amalgam restorations and assessed the failure, marginal fracture and marginal staining behavior of 366 Permite C amalgam restorations lined with five dentin bonding resins (Scotchbond 2, Panavia Ex, Amalgambond, Amalgambond Plus, Geristore) and a polyamide cavity varnish (Barrier). The restorations were placed in the posterior permanent teeth of 190 adult patients and examined at intervals over periods of up to five years. There were five restoration failures (1.4%), usually from tooth fracture, involving Class II preparations in molar teeth. No instances of persistent pulpal sensitivity or recurrent caries were reported. The marginal deterioration of the restorations was assessed indirectly using photographs for comparison with two standard sets of enlarged color transparencies. Most of the marginal fracture and marginal staining scores were low, with little difference between the six lining materials at any period.

[A morphological assessment of periodontal tissue status in the postshock traumatic period in an experiment]. / Morfologicheskaia otsenka sostoianiia tkanei parodonta v postshokovom travmaticheskom periode v éksperimente.

Shockogenic sublethal mechanical multiple injuries were induced in outbred albino rats according to the method developed by Noble-Collip and periodontal tissues were examined histomorphologically in various periods after shock. Atrophic changes in periodontal tissues and dental pulp progressed starting from day 1 and reached the maximum on day 28. The greatest shifts were observed in the gingivodental epithelium (hyperkeratosis), periodontium (lymphocyte and macrophage infiltration), alveolar bone (lacunar resorption), and pulp (odontoblast reduction and decreased pulpocyte count). Phasic reactive changes in the periodontium after shock and trauma require timely correction.

Model for quantitative immunohistochemical assessment of pulpal response to biomaterials.

The purpose of this study was to propose a new method for quantitative evaluation of the pulpal inflammation to restorative materials using immunohistochemistry and image analysis. Class V cavities were prepared and filled with different restorative materials in 20 healthy premolars to be extracted for orthodontic reasons. Teeth were extracted at different time intervals, fixed, demineralized, and embedded in paraffin. Six-micrometer-thick sections were cut serially and mounted on slides and every fifth section was stained using hematoxylin and eosin or Masson's trichrome, and served to localize the inflammatory reaction. The slides corresponding to the bulk of the inflammatory reaction were then used for immunohistochemical detection of the inflammatory cells using monoclonal antibodies: CD15 (granulocytes and histiocytes), CD45RO (T lymphocytes and monocytes), Pan-B cell (B lymphocytes, macrophages, and a subpopulation of T lymphocytes), CD45RA (B lymphocytes and monocytes), and EMA (plasma cells). The slides were observed and submitted to computerized image analysis using a SAMBA 2000 system for counting of the cells. The CD15, CD45RO, Pan-B-cell, and CD45RA antibodies positively stained the target cells, which could be counted with the computer. The EMA antibody did not permit staining of cells. These results indicate that polymorphonuclears, T lymphocytes, and B lymphocytes are present in inflamed human dental pulp. The immunologic detection of inflammatory cells followed by computerized image analysis allows an accurate characterization of pulpal pathology, and could be useful for the study of pulp reactions to restorative biomaterials.