Comparison of the Depth of Cure of Flowable Composites Polymerized at Variable Increment Thicknesses and Voltages: An In vitro Study

Objectives

The aim of this study is to compare the depth of cure of two composite materials (SDR and Filtek bulk-fill) cured at variable increment depths (2, 4, and 6 mm) and voltages (180 and 220 volts).

Materials and Methods

Each sample of the composite material was packed in a mold of 2 mm, 4 mm, and 6 mm and curing light (quartz tungsten halogen) of optimal intensity was exposed for 20 s at 2 different voltages on each specimen. After curing, the specimens were removed and the composite on the nonexposed end was scraped with a plastic instrument. The remaining composite thickness was measured using a digital Vernier caliper. The reading was divided by half to follow the ISO 4049 method. Independent sample t-test, one-way ANOVA, and linear regression analysis were applied. Level of significance was kept at 0.01.

Results

The mean DOC of SDR and Filtek were 1.93 ± 0.82 and 1.77 ± 0.65 mm. Lowering the voltage from 220 to 180 volts reduced the depth of Filtek from 1.87 ± 0.74 to 1.67 ± 0.54 mm, whereas the DOC of SDR remained unchanged at 1.93 mm at the two voltages. The adjusted R ² for the depth of cure was 0.93 when the increment thickness, voltage, and restorative material were taken together in the regression model.

Conclusions

There was no statistically significant difference between SDR and Filtek for the depth of cure at 2 and 4 mm increments. However, at 6 mm increment, the SDR cured significantly deeper than the Filtek. Around 91% variation in the depth of cure of these composites materials is explained by increment thickness alone.

Management of immature necrotic permanent teeth with regenerative endodontic procedures - a review of literature

Immature necrotic permanent tooth presents a distinctive challenge for the endodontist. Various treatment modalities have been employed to create hard tissue barrier at the apex, which includes non-vital pulp therapy with calcium hydroxide, apexification with mineral trioxide aggregate, pulp revascularisation and regeneration. Regenerative endodontics is a novel modality which involves physiological replacement of the damaged structures of tooth like dentin, root and cells of the pulp-dentin complex. Numerous published case reports have revealed increased dentinal wall thickness, continued root development and apical closure, but there is still lack of sound scientific evidence regarding histological nature of the type of tissue. The current literature review was planned to summarise the evidence regarding the treatment of immature necrotic permanent teeth by regenerative endodontic procedures.

Most effective method for the management of physiologic gingival hyperpigmentation: A systematic review and meta-analysis

Background and Aim:

Gingival hyperpigmentation is an esthetic problem. The aim of the present study was to identify most effective treatment modality for managing generalized physiological gingival pigmentation.

Materials and Methods:

A systematic review and meta-analysis were done (1919 to October 2018) using PubMed, CINHAL, Dental and Oral Science, and manual searches. Twenty-five articles were finally reviewed. Only human clinical trials were considered with physiological gingival pigmentation treated with different depigmentation methods and compared with surgical stripping. The outcome was the achievement of gingival depigmentation and its recurrence. RevMan software was used for data analysis.

Results:

Of 26,132 articles, 25 met the inclusion criteria. Seventeen were randomized control trials and 8 were nonrandomized control trials. Most of the studies were on laser. The control group was scalpel surgery. Majority of studies showed no difference in compared treatment modality. A meta-analysis compared laser ablation with surgical stripping revealed a nonsignificance difference regarding recurrence (P = 0.75) and depigmentation (P = 0.23) and a statistically significant difference regarding postoperative pain favoring laser ablation (P ≤ 0.05).

Conclusions:

Surgical stripping has been the conventional treatment of choice, but our review showed that new techniques are equally effective or even better. Laser especially diode laser was the most frequently used technique and showed better esthetic outcomes, less pain, faster healing, and patients' preference and satisfaction after treatment. However, laser showed more regimentation at 6-month evaluation. More good quality randomized controlled trials with different depigmentation methods are needed to draw strong conclusions.

Assessment of iatrogenic damage to adjacent teeth during crown and bridge preparation

Introduction

Iatrogenic damage to the adjacent tooth during crown preparation is a frequent disastrous effect. The aim of the study was, therefore, to determine the frequency of different types, degree and location of iatrogenic damage to the adjacent tooth during crown and bridge preparations in a tertiary care setting that lead towards the morbidity of tooth.

Materials and Methods

A prospective study was conducted in Aga Khan University dental laboratory in two months period in which a total of 150 dental casts fulfilling the inclusion criteria were analyzed using non-probability convenient sampling technique. The casts were examined using 3.5x magnifying loupes for the location, degree and type of damage to the proximal surface adjacent to the prepared tooth using Moonpar and Faulkner criteria. Data were analyzed by using SPSS version 22. Chi square test was used to assess the association between the experience of practitioner and degree of damage to adjacent tooth. It was also used to determine the association between location of tooth and degree of damage to adjacent tooth. Inter-examiner reliability was assessed by using kappa statistics.

Results

A high prevalence of damage to the proximal surface of adjacent teeth (78% on mesial tooth and 60.6% on distal tooth) was observed, with the majority (32.6%) belonging to the mild categories. There were statistically significant associations between the experience of practitioner and the damage to the surface mesial to the preparation. However, more severe damages occurred in mandibular teeth preparations as compared to maxillary teeth preparations.

Conclusions

A high frequency of iatrogenic damage to the adjacent teeth had been found during crown and bridge work with the middle of the tooth as the most susceptible site. However, the majority of damages were of milder type including only abrasions.

Awareness of dentists regarding immediate management of dental avulsion: Knowledge, Attitude, and Practice study

OBJECTIVE

To assess the knowledge of practising dentists regarding immediate management of dental avulsion.

METHODS

The cross-sectional analytical study was conducted in various dental colleges and teaching hospitals of Karachi, Pakistan, in October-November 2016, and comprised dentists working in academic institutions / departments or as general dental practitioners for at least 1 year. The subjects were asked to fill out a self-administered questionnaire. Questions related to knowledge and practice regarding immediate management of dental avulsion was asked and then responses were categorised as good knowledge, moderate and poor knowledge. SPSS 22 was used for data analysis..

RESULTS

Of the 282 subjects, 179 (63.5%) were females and 103(36.5%) were males. The overall mean age was 28. 33±4.7 years, and 194 (68.8%) had clinical experience of less than 5 years. Of the total, 30(11%) dentists had good knowledge while 130(46%) had moderate and 122(43%) had poor knowledge. Statistically significant association of knowledge regarding tooth avulsion was observed with the specialty (p= 0.006) and qualification (p=0.001).

CONCLUSIONS

The knowledge of dentists regarding immediate management of avulsion injuries was inadequate. Knowledge was significantly associated with specialty and qualification of the dentist.

Management of extensive external apical root resorption leading to root perforation

Resorption is both a physiological and pathological process which results in loss of hard tissues of the tooth, i.e , cementum and dentine and the surrounding bone. External resorption is much more common than internal resorption and can occur when tooth is luxated or avulsed. If remained unchecked, resorption can eventually lead to loss of the tooth. Timely management of the affected tooth can slow down the resorptive lesion and increase the prognosis of the survival of the tooth. This case report describes the surgical management of extensive external root resorption leading to perforation of apical one-third of the root area which was managed through root canal along with periapical surgery and bone grafting. A 6-month follow-up showed arrest of the resorptive defect and progressive healing as evident on the cone-beam computed tomography.

Prevalence of musculoskeletal disorders among dentists in teaching hospitals in Karachi, Pakistan

Work-related musculoskeletal pain is common among healthcare professionals, including dentists. This cross-sectional study was conducted to determine the prevalence of work-related musculoskeletal disorders (MSDs) among dentists. This study was carried out from January to April 2016 at various teaching hospitals of Karachi, and comprised 230 dentists. A self-administered questionnaire, adapted from a validated Nordic questionnaire, was distributed among the participants. Descriptive statistics were computed and associations of interest were analysed using chi-square test. Of the 230 forms, 182(79.11%) were included after leaving out the incomplete ones. The overall prevalence of MSDs was 138(75.8%). The most frequent reasons for MSDs were lack of rest 21(15.2%) and having static postures for more than half-an-hour per procedure 38(27.5%).

Age estimation of a sample of Pakistani population using Coronal Pulp Cavity Index in molars and premolars on Orthopantomogram

The aim of the present study was to assess the validity of tooth-coronal index (TCI) in the age estimation. This retrospective charts review was conducted at the Aga Khan University Hospital, Karachi from January 2016 to March 2016, and comprised 315 teeth of 80 individuals. The teeth were analysed on Orthopantomogram. TCI was calculated for unrestored mandibular premolars and molars. Pearson\\\'s correlation was applied to assess correlation between chronological age and TCI. Besides, 30(37.5%) subjects were male and 50(62.5%) female, and 140(44.4%) teeth were of male subjects and 175(55.6%) were of females. The mean correlation coefficient between chronological age and TCI was -0.27. The highest negative correlation was observed for tooth No.47 in males (r=-0.72) whereas among females the highest negative correlation was noted for tooth No.36 (r=-0.61).There was very weak correlation between age and TCI of a tooth. Therefore, TCI index could not be predictably used for age estimation in the studied population.