• Journal of Oral Medicine and Pain
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• v.46 no.2
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• pp.21-32
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• 2021

Purpose: The purpose of the present study was to investigate the correlation between age and 34 radiomorphometric parameters on panoramic radiographs, and to provide generalized linear models (GLMs) as a non-invasive, inexpensive, and accurate method to the forensic judgement of living individual's age. Methods: The study included 417 digital panoramic radiographs of Korean individuals (178 males and 239 females, mean age: 32.57±17.81 years). Considering the skeletal differences between the sexes, GLMs were obtained separately according to sex, as well as across the total sample. For statistical analysis and to predict the accuracy of the new GLMs, root mean squared error (RMSE) and adjusted R-squared (R²) were calculated. Results: The adjusted R²-values of the developed GLMs in the total sample, and male and female groups were 0.623, 0.637, and 0.660, respectively (p<0.001), while the allowable RMSE values were 8.80, 8.42, and 8.53 years, respectively. In the GLM of the total sample, the most influential predictor of greater age was decreased pulp area in the #36 first molar (beta=-26.52; p<0.01), followed by the presence of periodontitis (beta=10.24; p<0.01). In males, the most influential factor was the presence of periodontitis (beta=9.20; p<0.05), followed by the number of full veneer crowns (beta=2.19; p<0.001). In females, the most influential predictor was the presence of periodontitis (beta=18.10; p<0.001), followed by the tooth area of the #16 first molar (beta=-11.57; p<0.001). Conclusions: We established acceptable GLM for each sex and found out the predictors necessary to age estimation which can be easily found in panoramic radiographs. Our study provides reference that parameters such as the area of tooth and pulp, the number of teeth treated, and the presence of periodontitis should be considered in estimating age.

• The Korean Journal of Legal Medicine
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• v.42 no.4
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• pp.141-145
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• 2018

There have been many radiographic studies on age estimation that evaluate reduction in size of dental pulp cavity with secondary dentin formation. The Paewinsky method reported high accuracy in estimating ages by measuring the width of the pulp cavity in panoramic radiographs. The aim of this study was to evaluate the application of the Paewinsky method to digital periapical radiographs. This study was conducted on 103 cases that reported to the Section of Human Identification of the National Forensic Service. The age was calculated by applying the Paewinsky method that measures the root and pulp canal width at three points in a tooth. The estimation results were compared with those calculated by the Johanson method. When the Paewinsky models were applied to digital periapical radiographs, the errors were significantly greater as compared to the original study. The errors of the maxillary second premolar and mandibular lateral incisor were greater than those of the maxillary central incisor, lateral incisor, mandibular canine, and first premolar. Furthermore, errors of the age estimation models in level C were greater than those in levels A and B. This study could be a reference for the application of the Paewinsky method to digital periapical radiographs.

• Restorative Dentistry and Endodontics
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• v.48 no.4
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• pp.33.1-33.12
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• 2023

Objectives: This study aimed to evaluate the bleaching efficacy and hydrogen peroxide permeability in the pulp chamber by the at-home bleaching gel in protocols applied on different dental surfaces. Materials and Methods: Forty premolars were randomly into 4 groups: control group no bleaching, only application on the buccal surface (OB), only application on the lingual surface (OL) and application in buccal and lingual surfaces, simultaneously (BL). At-home bleaching gel (White Class 7.5%) was used for the procedure. The bleaching efficacy was evaluated with a digital spectrophotometer (color change in CIELAB [ΔE_ab] and CIEDE 2000 [ΔE₀₀] systems and Whitening Index for Dentistry [ΔWI_D]). The hydrogen peroxide permeability in the pulp chamber (㎍/mL) was assessed using UV-Vis spectrophotometry and data were analyzed for a 1-way analysis of variance and Tukey's test (α = 0.05). Results: All groups submitted to bleaching procedure showed bleaching efficacy when measured with ΔE_ab and ΔE₀₀ (p > 0.05). Therefore, when analyzed by ΔWI_D, a higher bleaching efficacy were observed for the application on the groups OB and BL (p = 0.00003). Similar hydrogen peroxide permeability was found in the pulp chambers of the teeth undergoing different protocols (p > 0.05). Conclusions: The application of bleaching gel exclusively on the OB is sufficient to achieve bleaching efficacy, when compared to BL. Although the OL protocol demonstrated lower bleaching efficacy based on the ΔWI_D values, it may still be of interest and relevant in certain clinical scenarios based on individual needs, requiring clinical trials to better understand its specificities.

• Restorative Dentistry and Endodontics
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• v.15 no.1
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• pp.1-15
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• 1990

The aim of this study was to investigate the effect of dental therapeutic agent on conduction velocity and threshold current of intradental A- and C-fibers in the cat. Inferior alveolar nerve of cat anesthetized with sodium pentobarbital was exposed and dissected until response of functional single pulp nerve until could be evoked by monopolar electrical stimulation of the crown of the lower left canine teeth. 10ms rectangular pulse was used to determine the threshold current and 1ms rectangular pulse was used to determine conduction velocity. After application of calcium chloride (1, 2, 6M), calcium hydroxide mixed with saline, potassium chloride (0.2, 0.8, 1.6M), eugenol, zinc oxide eugenol to the cavity on the labial surface, conduction velocity and threshold current of single pulp nerve unit were compared with the control. In 10 cats, 24 $A{\delta}$- and 11 C- pulp nerve units were recorded. The mean conduction velocities of $A{\delta}$- and C-fibers were 7.5m/sec (SD=5.8) and 1.2m/sec (SD=0.4), respectively. The mean threshold current was $12.3{\mu}A$ (SD=5.3) for $A{\delta}$-fibers and $24.9{\mu}A$ (SD=8.1) for C-fibers. 1, 2, 6M calcium chloride caused decrease of conduction velocity and remarkable increase of threshold current in $A{\delta}$- and C-fibers. The effect of calcium hydroxide mixed with saline was similar but smaller than calcium chloride solution. 0.2M potassium chloride had insignificant effect. In 0.8M potassium chloride, the threshold current was increased although conduction velocity was not affected. In 1.6M potassium chloride, the threshold current was increased and the conduction velocity was slowed down. Spontaneous activity was recorded frequently for first 5 min but gradually reduced both in $A{\delta}$- and C-fibers. Eugenol had irreversible effect on pulp nerve in that initially there were not certain changes in the conduction velocity and threshold current of $A{\delta}$- and C-fibers, but the responses to electrical stimulation were abruptly disappeared after sustained application and were not recovered. Contrary to eugenol, zinc oxide eugenol did not caused significant increase of the threhold current and caused time dependent decrease of the conduction velocity, and did not show any irreversible change.

• Imaging Science in Dentistry
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• v.37 no.3
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• pp.165-170
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• 2007

Purpose: To estimate the shape of root and pulp canal using a dental cone beam computed tomography (CBCT) and to evaluate the accuracy of imaging reformation. Materials and Methods: CBCT images were obtained with incisors, premolars, and molars as the destination by using PSR $9000N^{TM}$ Dental CT system (Asahi Roentgen Ind. Co., Ltd, Kyoto, Japan) and i-CAT (Imaging Sciences International, Inc, USA) cone beam CT unit that have different kind of detector and field of view, and compared these with the shape and the size of actual root and root canal. Results: When the measuring value of cone beam computed tomography concerning to each root's bucco-lingual diameter and mesio-distal diameter was compared with the value of the actual root, it reveals an error range $-0.49{\sim}+0.63$ mm at PSR900N and $-0.97{\sim}+1.14$ mm at i-CAT (P>0.05). It was possible to identify and measure PSR$9000N^{TM}$ Dental CT system to the limit $0.48{\pm}0.06mm$ (P>0.05) and i-CAT CBCT to the limit $0.86{\pm}0.09mm$ (P<0.05) on estimating the size and the shape of root canal. Two kinds of CBCT images revealed the useful reproducibility to estimate the shape of root, but there was the difference to estimate the shape of root according to apparatus. The reproducibility of root shape in the image of three-dimensions at PSR 900N is low such as 0.65 mm in a case of minute root canal. Conclusions: CBCT images revealed higher accuracy of the imaging reformation for root and pulp and clinically CBCT is a useful diagnostic tool for the assessment of root and canal. However, there are different qualities of imaging reformation according to CBCT apparatus and limitation of reproducibility for minute root canals.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.4
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• pp.576-580
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• 2003

A 7-year-old male was refered to Department of Pediatric Dentistry, Wonkwang Dental Hospital for treatment of a traumatic injury to the teeth of the maxillary anterior region of the mouth. His right central incisor presented subluxation and root fracture, the left central incisor had suffered intrusive luxation and root fracture. The initial treatment involved reposition and fixation of the teeth with 0.5mm stainless steel wire and composite resin. The patient was submitted for clinical and radiographic fallow-up. After 4 years, radiographically the right central incisor seemed to be healed by hard tissue union and showed to be indistinct fracture line, intact lamina dura. The left central incisor radiographically was healed by interposition of bone and connective tissue and showed to be distinct horizontal fracture line separating the fragments, and pulp canal obliteration. In clinical examination, the teeth showed a normal response to elective pulp test, percussion and mobility test. Pulp survival after injuries appears to be dependent upon the type of luxation injury, age of patient, stage of root development and degree of dislocation. In this case, the two teeth with incomplete root formation were suffered different type of injury by trauma and has showed different healing aspect.

• Journal of Oral Medicine and Pain
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• v.20 no.1
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• pp.229-246
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• 1995

The deoxyribonucleic acid(DNA) was isolated from the pulp, dentin and enamel of the 4 fresh teeth and the 7 teeth left in room temperature for 10 years. Then it was examed to find out the usefulness for forensic dental medicine. Samples of the tooth-derived DNA amplified by polymerase chain reaction(PCR), electrophosed for sex determination by detection of X-Y homologous amelogenin gene and D1S80 locus detection. The following results have been achieved. DNA extraction was possible in pulp and dentin of the fresh teeth, so it could be applicatable to detection of X-Y homologous amelogenin gene for sex determination, amplification of D1S80 locus by PCR. Sex determination was possible in pulp and dentin of the teeth left at room temperature for 10 years. Also, possible the detection fo AMP-FLPs to increase PCR cycling up to 40. DNA was isolated from all pulp of the fresh teeth and the teeth left in room temperature for 10 years, and also isolated from the dentin of the fresh teeth, partially isolated(3/7) from the dentin of the teeth left in room temperature for 10 years, but DNA was not isolated from enamel. From the above investigation, DNA extraction, sex determination, amplification of D1S80 locus were successfully accomplished even though the teeth were left for 10 years at room temperature. Therefore, teeth, especially pulp, are highly reliable and applicable as molecular biological samples for individual identification.

• Restorative Dentistry and Endodontics
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• v.40 no.3
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• pp.241-248
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• 2015

Variation in root canal morphology, especially in maxillary first molar presents a constant challenge for a clinician in their detection and management. This case report describes the successful root canal treatment of a three rooted right maxillary first molar presenting with three canals each in the mesiobuccal and distobuccal roots and one canal in the palatal root. The clinical detection of this morphologic aberration was made using a dental operating microscope, and the canal configuration was established after correlating and computing the clinical, radiographic and cone-beam computed tomography (CBCT) scan findings. CBCT images confirmed the configuration of the canals in the mesiobuccal and distobuccal roots to be Al-Qudah and Awawdeh type (3-2) and type (3-2-1), respectively, whereas the palatal root had a Vertucci type I canal pattern. This report reaffirms the importance of careful examination of the floor of the pulp chamber with a dental operating microscope and the use of multiangled preoperative radiographs along with advanced diagnostic aids such as CBCT in identification and successful management of aberrant canal morphologies.

• Journal of Dental Anesthesia and Pain Medicine
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• v.23 no.1
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• pp.9-17
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• 2023

Background: Dental evaluation and protection are important for preventing traumatic dental injuries when patients are under general anesthesia. The objective of the present study was to develop a questionnaire based on dentition-related risk factors that could serve as a valuable tool for dental evaluation and documentation. Methods: We developed a questionnaire for dental evaluation before administration of general anesthesia, investigated the association between patient-and-dentist responses and mouthguard fabrication, and assessed response agreement between 100 patients. Results: Protective mouthguards were fabricated for 27 patients who were identified as having a high risk of dental injury. There was a strong association between dentists' responses and mouthguard fabrication, depending on the general oral health status, use of ceramic prosthesis, presence of masticatory pain related to periodontal diseases, gingival edema, and implants (P < 0.05). Response agreement between patients and dentists for items related to dental pain, loss of dental pulp vitality, root canal therapy, dental trauma, aesthetic prosthesis, tooth mobility, and implant prosthesis was high (Cohen's kappa coefficient κ ≥ 0.6). Conclusions: A high agreement was observed between patient-dentist responses and a strong association with mouthguard fabrication for items pertaining to ceramic prosthesis, masticatory pain, and dental implants. Patients with a "yes" response to these items are recommended to undergo a dental evaluation and use a dental protective device while under general anesthesia.

• Restorative Dentistry and Endodontics
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• v.42 no.2
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• pp.146-151
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• 2017

X-linked hypophosphatemia (XLH) is a hereditary metabolic disease caused by the loss of phosphate through the renal tubules into the urine, and an associated decrease in serum calcium and potassium phosphate. Its dental features include spontaneous dental abscesses that occur in the absence of trauma or dental caries. The aim of this case report was to describe the dental problems of XLH patients and to evaluate limitations in their treatment. A 14 year old male and a 38 year old female with XLH were referred to the Department of Conservative Dentistry for endodontic treatment. The dental findings were periapical abscesses without obvious trauma or caries. Conservative endodontic treatment was performed in teeth with pulp necrosis and abscess. In case 1, the treated teeth showed improvements in bone healing, without clinical symptoms. However, in case 2, the implants and the treated tooth showed hypermobility, and the final restoration was therefore postponed. Early diagnosis, periodic examinations, and communication with the patient's pediatrician are important in the dental management of patients with XLH.