Half Of Dentin Research Articles

Deep carious lesions and their management among Finnish adolescents: a retrospective radiographic study

ObjectiveThe objective of this retrospective study was to find out (i) the prevalence of deep carious lesions, both untreated and previously treated, among 14- and 15-year olds and (ii) how deep carious lesions were managed in a Finnish public health care setting.Materials and methodsA random sample of 278 patients was taken from 3990 patients at the oral health care of the City of Helsinki. Radiographic subsample consisted of patients with bitewing and periapical radiographs (n = 128, 46% of the total sample). Deep carious lesions (extending to at least the inner half of dentine), deep restorations, direct pulp cappings, root canal treatments, and extractions in permanent premolars and molars were recorded from the radiographs. Patients with untreated deep carious lesions were followed up for 24 months.ResultsIn the total sample 12% had at least one untreated deep carious lesion, 10% at least one deep restoration, and 19% at least one untreated or previously treated deep carious lesion. The follow-up cohort included 48 deep carious lesions in 26 patients. Complete excavation was the most frequently chosen method (81% for lesions reaching the inner half of dentine and 56% the inner third or deeper), followed by stepwise excavation (19% and 37%, respectively).ConclusionsOne-fifth of 14–15-year-olds had at least one untreated or previously treated deep carious lesion. The choice for the carious tissue removal did not follow the current recommendations for less invasive methods.Clinical relevanceContinuing education is needed to improve the diagnostics and management of deep carious lesions.

Detection of Approximal Caries Lesions in Adults: A Cross-sectional Study.

Detection and management of posterior approximal caries lesions are still problematic. Inspection of approximal surfaces is challenging, and bitewing radiographs are used when direct vision is not possible. Unfortunately, there is no definite radiographic appearance to identify lesion cavitation with absolute certainty. Many lesions detected radiographically within the outer half of dentin are not cavitated, often resulting in unnecessary restorative treatment. Our study compared radiographic depth of approximal caries lesions with presence of cavitation in adults using visual inspection following temporary tooth separation (TTS). We conducted this observational descriptive cross-sectional study at two dental schools in two cities in Chile. Clinicians were unaware of radiographic depths of lesions and examined 147 participants (57.3% female and 42.7% male) following TTS. Using the common classification system that consists of E0 (no lesion), E1 (lesion within the outer half of enamel), E2 (lesion within the inner half of enamel), D1 (lesion within the outer third of dentin), D2 (lesion within the middle third of dentin), and D3 (lesion within the inner third of dentin), a trained dentist evaluated all the processed films. Cavitation was detected in only three sites (0.22%) within the E0 category, seven sites (3.41%) in E1, five sites (14.8%) in E2, four sites (14.8%) in D1, six sites (50%) in D2, and eight sites (61.5%) in D3. Considering that restorative treatment should be indicated strictly for cavitated lesions, our findings support indication for restorative treatment for D3 lesions and the rationale for TTS for D1-D2 caries lesions to allow direct visual inspection to determine whether there is surface cavitation.

Dental caries lesions in primary teeth without obvious cavitation: Treatment decision-making process.

Dental caries diagnosis and management have changed over time. To identify the treatment decision-making process performed by paediatric dentists, after caries detection using CAST instrument (Caries Assessment Spectrum and Treatment), for enamel (CAST 3) and non-cavitated dentin caries lesions (CAST 4) before and after analysing radiographic images. Seventy-four paediatric dentists were invited to participate. Twelve clinical cases were presented online, and treatment decisions before and after the analysis of bitewing radiographs were evaluated. Sixty-one specialists answered the questionnaire. The necessity for radiographs was significantly associated with the presence and depth of the caries lesion (P<0.0001). CAST 3 lesions were preferentially monitored before and after the radiographic assessment. For CAST 4 lesions limited to the outer half of dentin, treatments indicated before and after radiographic analysis were sealant (33%) and restoration (40%). For the lesions in the inner half of dentin, restoration was the most cited before (45%) and after (84%) radiographs. The radiographic depth was the only significant independent variable when "change in the treatment option" was analysed by the regression model (P<0.001). Enamel lesions were treated through less invasive treatments. Radiographs influenced the decision, especially for the lesions that involved the inner half of dentin.

Radiographic pattern of underlying dentin lesions (ICDAS 4) in permanent teeth.

To assess the radiographic pattern of underlying dentine shadows (UDS) in the occlusal surfaces of permanent teeth. A total of 282 permanent posterior teeth pertaining to 91 individuals, 142 UDS and 140 non-cavitated enamel lesions (NCEL), were included for comparison. UDS was defined as shadows of discolored dentin visible through the enamel surface which may or may not show signs of localized enamel breakdown, classified as code 4 by the International Caries Detection and Assessment System group. Data collection included the application of a questionnaire, clinical examination, and bilateral bitewing radiographs. The risk for presenting radiolucency was estimated using logistic regression model with generalized estimating equations. Approximately 79% of UDS exhibited no radiolucency. The proportion of teeth exhibiting a radiolucency restricted to the enamel-dentin junction was 20.4% for UDS and 3.6% for NCEL (p < 0.001, chi-square test). UDS had a sixfold increased risk for exhibiting radiolucency compared with NCEL (OR = 5.78, 95% CI = 2.73-12.22, p < 0.001). Despite this finding, it is important to highlight that virtually all cases were located at the enamel-dentin junction, and only one tooth in each category of clinical status exhibited radiolucency at the outer one half of dentin. No tooth exhibited radiolucency reaching the deep dentin. The present study showed that UDS presented radiolucency in very few cases. The vast majority of lesions showed no radiolucency. Our findings suggest that only a small proportion of UDS would demand restorative treatment.

Microbiological analysis after complete or partial removal of carious dentin using two different techniques in primary teeth: A randomized clinical trial.

Background:The management of deep carious lesions can be done by various techniques but residual caries dilemma still persists and bacterial reduction in cavities treated by either partial or complete caries removal techniques is debatable. So the objective of the present randomized clinical trial was to compare microbial counts in cavities submitted to complete caries removal and partial caries removal using either hand instruments or burs before and after 3 weeks of restoration.Materials and Methods:Primary molars with acute carious lesions in inner half of dentine and vital pulp were randomly divided into three groups of 14 each: Group A: Partial caries removal using hand instruments atraumatic restorative treatment (ART) only; Group B: Partial caries removal using bur; Group C: Complete caries removal using bur and caries detector dye. Dentine sample obtained after caries removal and 3 weeks after restoration, were subjected to microbial culture and counting (colony-forming units [CFU]/mg of dentine) for total viable bacterial count, Streptococcus spp., mutans streptococci, Lactobacillus spp.Results:Three techniques of caries removal showed significant (P < 0.05) reduction in all microorganisms studied after 3 weeks of evaluation, but there was no statistically significant difference in percentage reduction of microbial count among three groups.Conclusion:Results suggest the use of partial caries removal in a single session as compared to complete caries removal as a part of treatment of deep lesions in deciduous teeth in order to reduce the risk of pulp exposure. Partial caries removal using ART can be preferred for community settings as public health procedure for caries management.

Occlusal Caries Extension in Relation to Visual and Radiographic Diagnostic Criteria: Results from a Microcomputed Tomography Study

This in vitro study aimed to evaluate occlusal caries extension in relation to visual and radiographic diagnostic criteria and their clinical value to indicate operative or preventive dental care. A total of 196 third molars with clinically sound occlusal fissures or noncavitated lesions were collected. Before microcomputed tomography (μCT) investigation, each tooth was examined visually and radiographically. Kühnisch's μCT-based caries-extension index (CE index) was used to determine the caries depth on a numeric scale (0 = sound; 0.01-0.99 = enamel caries; 1.0-1.99 = dentin caries). Sensitivities (SEs), specificities (SPs), and area under the receiver operating characteristic curve (Az value) were also calculated. Based on μCT data, the following mean CE index values and standard deviations (SDs) were documented according to the visual criteria: sound = 0.6 (0.4); first visible signs = 0.9 (0.4); established lesions = 1.3 (0.3); microcavities = 1.4 (0.2); dentin exposure = 1.5 (0.2); and large cavities = 1.5 (0.3). The radiographic categories according to Marthaler (enamel caries [D0-2], caries in the outer half of dentin [D3], and caries in the inner half of dentin [D4]) were related to CE index values of 0.9 (0.4), 1.4 (0.2) and 1.6 (0.4), respectively. Caries detected visually or radiographically showed an SE of 84% and an SP of 85% (Az = 0.85). When both methods were used to predict dentin involvement simultaneously, SE = 27%, SP = 100%, and Az = 0.63; this combined visual and radiographic approach was associated with a perfect specificity and no false-negative decisions. The proportion of false-positive diagnoses was moderately high, and lesion extension in these cases was mainly limited to the outer 20% of the dentin. Our results might be useful for differentiating between preventive and operative dental care for pits and fissures.

Effect of Postoperative Peroxide Bleaching on the Marginal Seal of Composite Restorations Bonded With Self-etch Adhesives

The aim of this study was to determine the effect of peroxide bleaching on the marginal seal of composite restorations bonded with several adhesive systems. Combined cylindrical Class V cavities located half in enamel and half in dentin were prepared on the buccal and lingual surfaces of human molars. The cavities were bonded with the self-etch adhesives Clearfil SE-Bond (CLF), Adper Prompt (ADP), and iBond (IBO) and an etch-and-rinse adhesive Gluma Comfort Bond (GLU) and restored with a microhybrid composite Charisma. Experimental groups were treated 25 times for eight hours per day with a peroxide bleaching gel Opalescence PF 20, while the control groups were stored in distilled water for two months and then subjected to a microleakage test using a dye penetration method. Scanning electron microscopy was used to investigate the etching and penetration abilities of the adhesives and morphology of debonded restoration-enamel interfaces after the microleakage tests. Statistical analyses were performed using nonparametric Kruskal-Wallis, Mann-Whitney, and Wilcoxon tests at p=0.05. The microleakage of all GLU groups was low and not significantly affected by peroxide bleaching. Low microleakage was recorded for CLF control groups, but after bleaching, a small but significant increase in microleakage at the enamel margin indicated its sensitivity to peroxide bleaching. For ADP and IBO control groups, the microleakage at the enamel margins was significantly higher than for GLU and CLF and exceeded that at the dentin margins. Bleaching did not induce any significant changes in the microleakage. Electron microscopy analysis indicated that in our experimental setup, decreased adhesion and mechanical resistance of the ADP- and IBO-enamel interfaces could be more important than the chemical degradation effects induced by the peroxide bleaching gel.

Use of glass ionomer cement containing antibiotics to seal off infected dentin: a randomized clinical trial

Dental materials with antibacterial properties can prevent the harmful effects caused by oral cariogenic bacteria. This double-blind controlled clinical trial evaluated the performance of a glass ionomer cement (GIC) added with antibiotics for sealing infected dentin in atraumatic restorations of primary molars. The study enrolled 45 children (45 teeth) between 5 and 8 years of age, of both genders, divided into two groups: GC (n=22), where cavities were lined with a conventional GIC (Vidrion F) and GA (n=23), with cavities lined with Vidrion F added with 1% each of metronidazole, ciprofloxacin and cefaclor antibiotic. Both groups were restored with Ketac Molar Easymix. Molars with carious lesions on the inner half of dentin without clinical or radiographic pulp damage were selected. Patients were evaluated clinically (pain, fistulas or mobility) and radiographically (area of caries, periapical region and furcation) after 1, 3, 6 and 12 months. For statistical analysis, chi-squared or Fisher's exact tests were used with a 5% significance level. GA (82.6-95.7%) had better results than GC (12.5-36.4%) in all evaluations (p<0.05) and the difference in the success rate was 46.2-72.5% higher for GA. The use of the antibiotic-containing GIC liner on infected dentin proved satisfactory when applied in deciduous teeth.

Self-etching aspects of a three-step etch-and-rinse adhesive

The purpose of this study is to assess the marginal adaptation of cavities restored with a three-step etch-and-rinse adhesive, OptiBond FL (OFL) under different application protocols. Twenty-four class V cavities were prepared with half of the margins located in enamel and half in dentin. Cavities were restored with OFL and a microhybrid resin composite (Clearfil AP-X). Three groups (n = 8) that differed in the etching technique were tested with thermomechanical loading, and specimens were subjected to quantitative marginal analysis before and after loading. Micromorphology of etching patters on enamel and dentin were observed with SEM. Data was evaluated with Kruskal-Wallis and Bonferroni post hoc test. Significantly lower percent CM (46.9 ± 19.5) were found after loading on enamel in group 3 compared to group 1 (96.5 ± 5.1) and group 2 (93.1 ± 8.1). However, no significant differences (p = 0.30) were observed on dentin margins. Etching enamel with phosphoric acid but avoiding etching dentin before the application of OFL, optimal marginal adaptation could be obtained, evidencing a self-etching primer effect. A reliable adhesive interface was attained with the application of the three-step etch-and-rinse OFL adhesive with a selective enamel etching, representing an advantage on restoring deep cavities.

An experimental study on the penetration abilities of resin infiltration into proximal caries lesions in primary molars

To compare the penetration abilities of resin infiltration into proximal lesions in primary molars with those of adhesive in vitro. Thirty-two extracted or exfoliated primary molars showing proximal white spot lesions were selected. Roots of the teeth were removed, and the crowns were cut across the white spot lesions perpendicular to the surface. Cut surfaces were examined (by stereo microscopy) and classified with respect to histological lesion extension (C1-C4): lesions confined to the outer half on enamel (C1), lesions confined to the inner half on enamel (C2), lesions confined to the outer half on dentin (C3), lesions extending into the inner half of dentin (C4). Corresponding lesion halves were etched for 120 s with 15% hydrochloric acid gel and were subsequently treated with either adhesive or resin infiltration. Specimens were observed with laser scanning confocal microscope (LSCM) in dual fluorescence mode. In confocal microscopic images, lesion depth and penetration depth of the resin infiltration or the adhesive in corresponding halves were measured, and penetration percentages were calculated respectively. Differences of the data between two groups were analyzed by Wilcoxon signed rank test. Variations of histological caries extensions were detected with Kruskal-Wallis H test. At the same grading level (C1-C3) in histological caries extension, penetration depths of the resin infiltration group and the adhesive group were 240 (230, 260) µm vs 190 (150, 210) µm, 405 (300, 523) µm vs 180 (160, 200) µm, and 590 (430, 640) µm vs 180 (160, 200) µm respectively. There was significant statistical difference in the data between two groups (P < 0.05). Statistically significant difference in penetration depths of the resin infiltration group (at C1-C3) were found (P < 0.01). At the same grading level (C1-C3) in histological caries extension, percentage penetrations of the resin infiltration group and the adhesive group were [100.0% (96.2%, 100.0%)], [99.1% (95.7%, 100.0%)], [82.0% (81.1%, 92.2%)] and [79.2% (68.4%, 87.5%)], [41.8% (29.1%, 74.5%)], [30.2% (29.2%, 39.6%)], respectively. The difference between the above data was also significant (P < 0.05). Percentage penetrations of the resin infiltration group at C1 and C2 level was higher than those at C3 level (P < 0.05). The resin infiltration is capable of penetrating almost completely into proximal lesions in primary molars.

Retention loss of class v restorations after artificial aging.

to evaluate whether retention loss of Class V restorations can be simulated in the laboratory and to compare these results with those from clinical trials. nonretentive v-shaped Class V cavities were prepared on the lingual and buccal side of extracted premolars, half in dentin and half in enamel. Different adhesive systems (AS) were used with the same composite resin (Tetric EvoCeram) and 12 restorations per group: 1-step self-etching AS (AdheSE One, Adper Prompt L-Pop, Futurabond N, Hybrid Bond, iBond, Xeno III, Xeno IV), 2-step self-etching AS (AdheSE), 2-step etch-and-rinse AS (Excite, Prime & Bond NT), 3-step etch-and-rinse AS (Syntac) as well as a conventional glass ionomer (Ketac Fil) with and without conditioner. The comparison groups were the composite without adhesive and a 2-step etch-and-rinse AS (Prime & Bond NT) without etching of enamel and dentin. The restored teeth were submitted to an aging process involving 18 months of water storage, three intermittent phases of thermocycling (TC 10,000 times), and two phases of thermomechanical loading (1 x 640,000 chewing cycles after 12 months, 1 x 1,200,000 chewing cycles after 18 months; 100 N sine-wave force profile, pressing with steel ball without lifting). Retention loss of the restorations was evaluated after every 1000 thermocycles and every 120,000 cycles of thermomechanical loading. The databases MEDLINE and IADR abstracts were used to search for clinical studies on retention loss involving the adhesive systems that were included in the present study. retention loss was only observed in the following groups: composite without adhesive (100% after first 1000 TC), glass ionomer without conditioner (8% after 6 months; 33% after 12 months, 100% after 18 months), adhesive without etching (17% after 6 months, 42% after 12 months). The laboratory results, however, matched with the clinical results only for three adhesive systems (Futurabond NR, Hybrid Bond, Xeno IV, 0% retention loss, 5 studies, observation period between 1.5 and 2 years). if the materials were applied according to the manufacturer's instructions, no retention loss was observed in the laboratory model. The laboratory model did not reflect the clinical findings.

Marginal seal stability of one bottle adhesives in Class V vs. Class I cavities

The aim of this study was to test the influence of two different cavity configurations on marginal stability of recent one bottle "etch & rinse" and "self-etch" adhesives in Class V vs. Class I cavities, before and after thermo-mechanical loading under simulation of dentinal fluid. Forty human upper molars were selected and assigned to five experimental groups. Intrapulpal pressure was maintained during cavity preparation, restoration placement, finishing and stressing. Standardized Class I and V-Shaped Class V cavities were prepared on each tooth. Half of the margins of Class V cavities were located in enamel and half in dentin. All cavities were restored with different adhesives systems and a nano-hybrid composite. Materials were light-cured using a LED unit. Restored teeth were loaded in a computer-controlled chewing machine with 1.2 million mechanical occlusal cycles simultaneously with 3,000 thermal cycles (5-50-5°C). Impressions were made with polyvinylsiloxane of each restoration before and after loading. Gold-coated epoxy replicas were prepared for SEM examination at ×200 magnification. Significant differences between materials were found both before and after loading (Kruskal-Wallis, Bonferroni, p < 0.05). Significant differences were also found between Class I and V restorations (Wilcoxon Matched-Pairs Signed-Rank Test, p < 0.05). Even before thermo-mechanical loading, none of the groups had 100% continuous margin. Marginal seal stability of recent one bottle "etch & rinse" and "self-etch" adhesives are significantly different and susceptible to cavity configuration.

Microbiological Analysis after Complete or Partial Removal of Carious Dentin in Primary Teeth: A Randomized Clinical Trial

Since viable bacteria can persist in tooth cavities regardless of the technique used for caries removal, the objective of the present randomized clinical trial was to examine the microflora of primary teeth treated by complete or partial removal of carious dentin. Deciduous molars with acute carious lesions in the inner half of dentin and vital pulp were randomly divided into two groups of 16: complete removal, in which the carious dentin was completely removed with the help of a caries detector dye, and partial removal, in which the carious dentin was completely removed from the dentinoenamel junction and lateral walls, while the necrotic carious dentin from the cavity floor was only removed superficially. Dentin samples were obtained with a sterile No. 3 bur after caries removal and 3–6 months after protection with calcium hydroxide cement and restoration of the cavities with resin composite. The samples were stored in thioglycolate. Decimal dilutions were then prepared and seeded for the enumeration of Streptococcus spp., mutans streptococci, Lactobacillus spp. and total microorganisms. Before sealing, a larger number of microorganisms was detected in teeth submitted to partial caries removal compared to the complete removal group. However, after sealing the level of colonization was similar in the two groups for all microorganisms studied. The results suggest that persistence of bacteria does not seem to be a reason for reopening of cavities in deciduous teeth after partial caries removal.

Unrestored Dentin Caries and Deep Dentin Restorations in Swedish Adolescents

The objectives of this longitudinal study were to assess: (a) the prevalence of unrestored dentin caries among 15-year-olds, (b) the proportion of these lesions that had progressed to deep dentin lesions (inner half of dentin) since the immediately preceding examination at the age of 14 and (c) the frequency of deep restorations (extending into the inner half of the dentin). The sample consisted of all 15-year-olds (n = 2,487) born in 1990 and included in the Public Dental Service in Malmö, Sweden. Bitewing radiographs taken during 2005–2007 and the immediately preceding radiographs were analysed and scored by two examiners. The main radiographic scores were: sound; radiolucency in the outer or inner half of dentin; restored surface. The results showed that 22% of the individuals had 1 or more dentin lesions left unrestored from the time of the examination at the age of 14 until the next recall examination at the age of 15. During the observation period (median time 1.2 years), 9% of the unrestored outer dentin lesions progressed to deep dentin lesions. The majority of these (93%) were in molars. One or more deep restorations were found in 22% of the 15-year-olds; the majority involved occlusal surfaces of first molars. In conclusion, unrestored dentin lesions were common in 15-year-olds. Progression to deep dentin lesions occurred in 9% of these lesions and was most common in first molars. Occlusal surfaces of first molars had the highest frequency of deep restorations.

Evaluation of the effectiveness of clinical and radiographic analysis for the diagnosis of proximal caries for different clinical experience levels: comparing lesion depth through histological analysis

Proximal cavity lesions are difficult to diagnose and are also hard to examine due to their location. Radiographic examination and teeth separation are resources used to help in caries diagnosis. The aim of this study was to evaluate, in different professional experience levels, the effectiveness of clinical and radiographic examinations in diagnosing proximal cavities, comparing lesion depth considered in these examinations to histological examinations. Thirty nine human teeth were used, 20 premolars and 19 molars, with clinical alterations on one proximal surface, such as lesions with either white or brownish stains and small cavitations which showed no clinical signs on the occlusal face, causing the professional insecurity in performing an accurate diagnosis as well as appropriate treatment. Samples were made using x-ray interproximal technique. Forty professionals of different experience levels performed clinical and radiographic examinations of the samples by filling out a form after classifying lesions depth. The samples were later sectioned for a histological analysis. Results showed that there was great variability on answers to examinations, with a low agreement percentage among examiners. After concluding all evaluated examinations, the examiners were not able to come up with an accurate diagnosis of lesions conditions on proximal cavities. The rate of cavitation was greater in lesions found on the external half of dentine, surpassing the amelodentinal limit, and an agreement percentage to conventional and digital x- ray examinations were equivalent.

Class II composite resin restorations with two polymerization techniques: relationship between microtensile bond strength and marginal leakage

To determine the relationship between leakage and microtensile bond strength in the same specimen of direct Class II composite restorations performed with two polymerization techniques. Class II slot preparations were made in 40 non-carious human third molars and restored using Single Bond and P-60 (3M ESPE) according to the manufacturer's indications. Half of the preparations had the cervical margin in enamel and half in dentin. Teeth were incrementally restored either with direct polymerization from occlusal surface or with indirect polymerization through translucent matrices and reflective wedges. Teeth were isolated with nail varnish and immersed in fucsin for 24h. Subsequently, they were sectioned into slabs that were measured for leakage (mm), and trimmed to obtain hour-glass shaped specimens for microtensile bond test. Fractured specimens were examined under magnification (40 x) to evaluate the fracture mode. Data were analyzed with Mann-Whitney and Kruskal-Wallis (microleakage), two-way ANOVA and Student-Newman-Keuls tests (bond strength). The relationship between microleakage and microtensile bond strength were analyzed with Spearman's correlation test. There were no significant effects of polymerization technique and margin location on both leakage and bond strength (p>0.05). Bond strengths were higher in preparations with enamel margins than in preparations with dentin margins, when restored with indirect polymerization technique (p<0.05). No significant correlation was found between leakage and bond strength (p>0.05). Polymerization techniques had no influence on microleakage and bond strength of Class II composite restorations, and there was no relationship between these variables when evaluated in the same specimen.

Clinical examination alone detects moresecondary caries on crowned teeth than radiograph alone

Summary Subjects The subjects were 100 patients with fixed prostheses 0689 who exhibited at least 1 secondary caries lesion. These subjects provided 820 teeth with crowns (365 single crowns, 455 fixed partial denture abutments) and 512 teeth with no restorations for the analyses. Exposure Both interproximal surfaces of each crowned and unrestored 0689 tooth were evaluated clinically and by radiographs for the presence of caries. The clinical examination included use of an explorer. Main outcome measure Presence of caries (clinical levels: initial caries, caries0689 suspicion, early caries, deep caries; radiographic levels: radiolucency limited to outer half of enamel, extending into inner half, reaching outer half of dentin, into inner half of dentin). Main results Clinical examination detected more caries lesions0689 (11.2%) on interproximal surfaces of crowned teeth than did radiographic examination (8.3%), a difference that was statistically significant at P . Conversely, radiographs detected slightly more lesions on interproximal surfaces of nonrestored teeth (4.1%) than did clinical examination (3.3%). This difference was also statistically significant ( P ).

Cavitation at radiolucent areas on proximal surfaces of posterior teeth.

To investigate the factors that influence the probability of clinical cavitation at radiolucent areas of proximal surfaces of posterior teeth, 108 molars and premolars with varying depths of proximal radiolucency were examined clinically, after cavity preparation on the carious contiguous tooth surfaces. The data obtained were subjected to logistic regression analysis with cavitation as the dependent variable, while age, tooth type and past caries experience (DMFT and DFS) were independent variables. When proximal radiolucency was confined to the outer half of enamel, there was no cavitation, but when it extended to the amelodentinal junction and the outer and inner half of dentine, there was cavitation in 19.3, 79.1 and 100% of cases, respectively. Moreover, there was a statistically significant relationship between the probability of cavitation, depth of radiolucency and age, suggesting that these should be among the main factors considered when restorative management of a radiolucent proximal surface of a posterior tooth is contemplated.