Dog Teeth Research Articles

Comparison of Pulpal Responses to Pulpotomy and Pulp Capping with Biodentine and Mineral Trioxide Aggregate in Dogs

IntroductionThis study evaluated the pulpal and periapical responses of dogs' teeth after pulpotomy and pulp capping with a new tricalcium silicate–based cement (Biodentine) when compared with mineral trioxide aggregate (MTA) by radiographic, histopathologic, and histomicrobiological analyses. MethodsSixty roots (30 teeth) of dogs were divided into 2 groups, Biodentine (n = 36 roots) and ProRoot MTA (control, n = 24 roots). Animals were killed after 120 days, and the teeth were subjected to histotechnical processing (hematoxylin-eosin and Brown and Brenn staining). Qualitative and quantitative histopathologic data were analyzed by Fisher exact and Mann-Whitney tests (α = 0.05). ResultsRadiographically, mineralized tissue bridge formation was observed in more specimens treated with Biodentine (96.8%) than with MTA (72.2%) (P = .02). Integrity of the lamina dura and absence of periapical bone rarefaction and root resorption (external and internal) were observed in all specimens. Histopathologic and histomicrobiological analyses revealed mineralized tissue bridge formation, pulpal vitality, odontoblast layer integrity, preserved periodontal ligament, and absence of bone or root resorption and microorganisms in both groups. Although the bridges formed at the amputation site had similar morphology, they were significantly thicker in the Biodentine group (P < .0001). Comparison between the radiographic and histopathologic results showed that radiographic visualization of more bridges in the Biodentine group was related to bridge thickness because radiographic diagnosis was flawed for bridges with thickness less than 0.5 mm. Fluorescence microscopy improved the visualization of bridge structure. ConclusionsBiodentine presented tissue compatibility and allowed for mineralized tissue bridge formation after pulpotomy in all specimens with similar morphology and integrity to those formed with use of MTA. Periapical radiographs failed in detecting mineralized tissue bridges with thickness less than 0.5 mm.

Outcomes of revascularization treatment in immature dog's teeth

The purpose of the current study was to examine the success rate of a revascularization treatment protocol involving canal space disinfection using copious irrigation, a triantibiotic dressing, and induction of a blood clot matrix in immature dog's teeth. Thirty-six immature mongrel dog's teeth were divided into two experimental and two control groups. The experimental groups included a necrotic-infected group (n = 20) and a vital group (n = 10). In the group with the necrotic-infected teeth, periapical lesions were induced, and disinfection of the canals was carried out using copious irrigation and a triple antibiotic medication (metronidazole, ciprofloxacin, and tetracycline). Subsequently, the periapical tissues were irritated to initiate bleeding, producing a blood clot. A double seal of the coronal access was then placed. In the vital group, the pulp was aseptically removed before the canal was irrigated and periapical tissues irritated to induce bleeding. The same protocol as that used for the necrotic-infected group was used to seal the coronal access. In the positive control group (n = 3), after pulp removal, sterile sponges soaked in plaque suspension were placed in the pulp chambers of the teeth, after which the chambers were sealed. In the negative control group (n = 3), one untouched 1st premolar tooth in each dog was assigned and left to develop naturally. Radiographic and histological findings were evaluated at 3 and 6 months. Data analysis was performed using Fisher's exact test. The necrotic-infected group radiographically demonstrated apical healing and apical closure in 70% of the cases and thickening of the walls in 40% after 6 months. The vital group showed apical closure in 77% and thickened walls in 44% of the cases after 3 months. Histological findings confirmed the radiographic findings. No significant difference was observed between the two groups (P > 0.05). If necrotic-infected canals are effectively disinfected and treated according to the protocol, the ensuing revascularization response is similar to that of vital immature teeth.

Effect of preparation surface area on the clinical outcome of full veneer crowns in dogs.

Crown therapy is commonly used in veterinary medicine to provide support to teeth which have previously fractured, received root canal therapy, have significant wear, or experienced other detrimental removal of tooth substance. As with several aspects of veterinary medicine, many of the recommendations or guidelines for crown therapy originate from human dentistry, which are then transferred to veterinary patients. Due to the significant difference in the anatomy of teeth and function of the oral cavity between humans and dogs, these guidelines need to be studied to determine the appropriateness of their use in veterinary patients. This article evaluates the relationship between surface area of the preparation and clinical outcome of full veneer crown therapy of the canine tooth in dogs. Although there appeared to be a positive relationship between preparations with greater surface area and successful clinical outcome, it was not found to be statistically significant.

Age-dependent decline in dental pulp regeneration after pulpectomy in dogs

The age-associated decline in the regenerative abilities of mesenchymal stem cells (MSCs) may be due to age-related changes in reduction in number, intrinsic properties of MSCs and extrinsic factors of the extracellular environment (the stem cell niche). The effect of age on the efficacy of MSC transplantation on regeneration, however, has not been clearly demonstrated due to variable methods of isolation of MSCs and variations in stem cell populations. In this study, dental pulp stem cell (DPSC) subsets were isolated from young and aged dog teeth based on their migratory response to granulocyte-colony stimulating factor (G-CSF) (MDPSCs). In order to study the age-associated changes, their biological properties and stability were compared and the regenerative potential was examined in a pulpectomized tooth model in aged dogs. MDPSCs from aged dogs were efficiently enriched in stem cells, expressing trophic factors with high proliferation, migration and anti-apoptotic effects as in MDPSCs from young dogs. However, pulp regeneration was retarded 120days after autologous transplantation of aged MDPSCs. We further demonstrated that isolated periodontal ligament stem cells (PDLSCs) from aged dogs, representative of migrating stem cells from outside of the tooth compartment to regenerate pulp tissue, had lower proliferation, migration and anti-apoptotic abilities. These results therefore provide a better understanding of the mechanisms involved in the age-dependent decline in pulp regeneration, which are attributed to a decrease in the regenerative potential of resident stem cells.

The Effect of EMD Application for Intentional Replantation of Periodontally Involved Teeth in Dogs

Background: Intentional replantation of periodontally involved teeth has been reported to result in unfavorable healing like root resorption and ankylosis. However, many recent clinical reports using enamel matrix derivative (EMD) showed a good outcome based on clinical and radiographic examination. However, histological findings are lacking. The purpose of this study was to evaluate healing after intentional replantation with EMD in a periodontally involved teeth model. Methods: A total of 20 incisors from seven beagle dogs were used. The periodontal ligament and cementum 5 mm from the coronal part of the roots were removed, whereas those in the apical part were preserved. Ten teeth of the experimental group were transplanted following application of EMD to the root surface. Ten teeth from the control group were transplanted without application. Eight weeks after transplantation, periodontal healing was analyzed. Results: Surface root resorption in the experimental group was significantly greater than in the control. New cementum formation was observed near the apical end of the planed root of the EMD group. Replacement resorption of the EMD group was significantly less than in the control. There was no significant difference in inflammatory resorption between groups. Conclusion: The combination use of EMD in intentional replantation resulted in new cementum formation on the root planed surface and inhibited root resorption and ankylosis. However, root resorption occurred at the coronal part in areas where the surface was root planed.

Mineral trioxide aggregate and portland cement for direct pulp capping in dog: a histopathological evaluation.

Background and aims. Mineral trioxide aggregate and calcium hydroxide are considered the gold standard pulp-capping materials. Recently, Portland cement has been introduced with properties similar to those of mineral trioxide aggregate. Histopathological effects of direct pulp capping using mineral trioxide aggregate and Portland cements on dog dental pulp tissue were evaluated in the present study.Materials and methods. This histopatological study was carried out on 64 dog premolars. First, the pulp was exposed with a sterile bur. Then, the exposed pulp was capped with white or gray mineral trioxide aggregates and white or gray Portland cements in each quadrant and sealed with glass-ionomer. The specimens were evaluated under a light microscope after 6 months. Statistical analysis was carried out using Kruskal-Wallis test. Statistical significance was defined at α=5%.Results. There was no acute inflammation in any of the specimens. Chronic inflammation in white and gray mineral trioxide aggregates and white and gray Portland cements was reported to be 45.5%, 27.3%, 57.1% and 34.1%, respectively. Although the differences were not statistically significant, severe inflammation was observed mostly adjacent to white mineral trioxide aggregate. The largest extent of increased vascularization (45%) and the least increase in fibrous tissue were observed adjacent to white mineral trioxide aggregate, with no significant differences. In addition, the least calcified tissue formed adjacent to white mineral trioxide aggregate, although the difference was not significant.Conclusion. The materials used in this study were equally effective as pulp protection materials following direct pulp capping in dog teeth.

Root canal disinfection of immature dog teeth with apical periodontitis: comparison of three different protocols

Objectives: The present in vivo study was designed to assess the efficacy of 3 root canal disinfection protocols in immature dog teeth with apical periodontitis (AP). Material and Methods: Forty immature premolars with pulp necrosis and AP of five Beagle dogs were used. Three experimental disinfection protocols were established. After irrigation with 40 ml 5.25% sodium hypochlorite using the Endovac system, in Group 1 canals were flushed with QMix solution; in Group 2, canals were flushed with QMix solution and 2% chlorhexidine gel dressing was placed for two weeks; and in Group 3, triantibiotic paste dressing was placed for two weeks. Canals were sampled after periapical lesions were radiographically visible (S1), after the first disinfection session (S2) and, in groups 2 and 3, after dressing (S3). Results: After the first session of the disinfection protocol (S2), there was significant (p < 0.05) bacterial reduction in the three experimental groups. Microorganisms were absent in 100% of S2 samples in groups 1 and 2, and in 75% of group 3 (p > 0.05). After dressing, 87.5% of the S3 samples showed increased bacterial count: in group 2, CFU counts (median = 891) were significantly higher than in group 3 (median = 18) (p = 0.03). Conclusions: In immature dog teeth with AP, root canal irrigation using QMix solution, with or without chlorhexidine gel dressing, or a triantibiotic paste dressing, provides the same level of disinfection than irrigation with 5.25% sodium hypochlorite alone in only one session. Key words:Apical periodontitis, chlorhexidine, Endovac, immature teeth, QMix solution, root canal disinfection, triantibiotic paste.

Periapical Inflammation Subsequent to Coronal Inoculation of Dog Teeth Root Filled with Resilon/Epiphany in 1 or 2 Treatment Sessions with Chlorhexidine Medication

IntroductionTherapeutic methods that inhibit microbial ingress into filled root canals are desirable. This in vivo study assessed the inhibition of periapical inflammation subsequent to coronal inoculation in canals medicated with 2% chlorhexidine gel and filled with Resilon/Epiphany (Pentron Clinical Technologies, Wallingford, CT). MethodsSix Beagle dogs each had 10 two-rooted premolars treated. In group 1 (n = 36 roots), 1 root/tooth had the canal conditioned with Primer Epiphany, filled with Epiphany sealer and Resilon core in 1 session, and coronally sealed with PhotacFil. In group 2 (n = 36 roots), the second root/tooth had the canal medicated with 2% chlorhexidine gel for 1 week and then filled and coronally sealed as in group 1. After 3 weeks, canals were exposed to the oral environment for 7 days, inoculated with isologous plaque, and coronally sealed. Negative controls treated as groups 1 and 2 remained sealed. Positive controls had canals unfilled and exposed. Seven months after inoculation, dogs were euthanized; jaw blocks processed for histologic examination; and periapical inflammation (PI) recorded as none, mild, or severe. ResultsIn groups 1 and 2, severe PI occurred in 5 of 65 roots (8%) and mild PI in 18 of 65 roots (28%) with a significantly higher (P = .031) PI incidence in group 2 than in group 1. Negative controls had only mild PI in 9 of 29 roots (31%). Roots medicated with 2% chlorhexidine gel had mild PI significantly more (P = .009) than roots filled in 1 session (more than 2-fold). ConclusionsIntracanal medication with 2% chlorhexidine gel and root filling with Resilon/Epiphany did not effectively inhibit apical periodontitis subsequent to coronal inoculation.

Effect of Indomethacin on Surface Treatment and Intracanal Dressing of Replanted Teeth in Dogs

This study evaluated the healing process of teeth replanted after root treatment and intracanal dressing with indomethacin alone or indomethacin with calcium hydroxide (Ca[OH]2). Through a case-control study, 24 teeth of 6 adult dogs were extracted, dried, and divided into 4 groups according to the root surface treatment protocols performed before replantation and the intracanal medication used after replantation. In group 1 (negative control), root surfaces were treated by immersion in a 0.9% saline solution and then replanted. In the other groups, the roots were immersed for 10 minutes in Ca(OH)2 (group 2), indomethacin (group 3), or a solution of indomethacin and Ca(OH)2 (group 4). After 2 weeks, group 1 teeth were subjected to single-visit root canal treatment and obturation with gutta-percha and sealer consisting of zinc oxide and eugenol. The teeth in the other groups were subjected to intracanal dressing with the same material used for immersion. After an additional period of 28 weeks, the animals were euthanized and the jaws containing the replanted teeth were processed for histologic analysis. Histometric values were statistically analyzed, with significance set at a P value less than or equal to .05. Group 1 exhibited significantly more normal periodontium than group 4 (P = .02). Total resorption was greater in group 4 than in group 1 (P = .02). No statistically significant difference in the percentage of surface resorption or in total inactive resorption was observed between the groups. The findings of this study suggest that intracanal dressing and topical root treatment with Ca(OH)2 with or without indomethacin is not recommended for teeth dried for 50 minutes, but the use of indomethacin alone as root surface treatment for delayed tooth replantation deserves further study using longer drying periods. In addition, the present results suggest that a single-visit root canal, performed up to 2 weeks after replantation, might be indicated for teeth dried for up to 50 minutes.

Porous chitosan bilayer membrane containing TGF-β1 loaded microspheres for pulp capping and reparative dentin formation in a dog model

ObjectivesThe objectives of this study were to develop a chitosan bilayer membrane containing microspheres with sustained TGF-β1 release to enhance odontoblast-like cell function in vitro, and to investigate pulp-capping in a dog model to promote reparative dentin formation in vivo for the first time. MethodsA chitosan bilayer membrane was synthesized consisting of a dense film on one side and a macroporous sponge on the other side. The rationale was to use the dense film to block the perforated pulp from bacterial invasion, and the porous sponge to be loaded with microspheres containing TGF-β1 (MS-TGF) for sustained release. Pulp capping in 48 teeth of six beagle dogs was performed to test four groups: Control with no pulp capping material, commercial Dycal, chitosan membrane without MS-TGF, and chitosan membrane with MS-TGF. The dog teeth were harvested for histological analysis at two time points (10 and 60d). ResultsThe spongy side of the membrane had macropores with a mean size of 151μm. The porosity of the membrane was 83%. Chitosan microspheres containing TGF-β1 showed sustained release, gradually releasing 42% of the TGF-β1 in 7d. The proliferation of odontoblast-like cells on membrane with MS-TGF was much greater than that without TGF (p<0.05). At 10d, H&E staining revealed mild to moderate pulp inflammation in all four groups, with no dentin bridge formation. At 60d, pulp inflammation disappeared, but there was no reparative dentin bridge in the group with no pulp-capping material. Chitosan membranes with MS-TGF generated reparative dentin with a thickness of (142±29)μm, 3–6 times thicker than that with Dycal or chitosan bilayer membrane without TGF (p<0.05). SignificanceA novel chitosan bilayer-microsphere construct containing TGF-β1 for pulp-capping generated 3–6 times more reparative dentin than the controls in a dog model for the first time. The chitosan bilayer-microsphere construct with growth factor delivery may be useful for a wide range of dental and regenerative medicine applications.

Histologic and Micro–Computed Tomographic Analyses of Replanted Teeth Stored in Different Kind of Media

IntroductionCoconut water (CW) and soy milk (SM) have been proposed as storage media for avulsed teeth because of their nutrients that preserve cell viability. The present study investigated the periodontal healing process of dog teeth replanted after storage in CW, SM, and whole milk (WM) using micro–computed tomographic (μCT) and histologic analyses compared with immediate tooth replantation. MethodsForty roots of 10 adult beagle dogs were extracted and subjected to the following protocols: immediate replantation after extraction (control), stored in CW with an adjusted pH, and SM and WM for 50 minutes before replantation. The animals were euthanized 28 days postoperatively, and the obtained specimens were scanned using a μCT scanner and subjected to routine processing for histometric analyses under an optical microscope. ResultsCW and SM performed similarly to WM; however, SM showed significantly higher ankylosis than the control group. ConclusionsAdditionally, this study showed that the combined use of histologic analysis and μCT is a promising method to better identify tooth resorption and the repair process and to evaluate the total extension of the periodontium. CW as a storage medium is a promising transport media for avulsed teeth.

Effects of orthodontic load on the periodontium of autogenously transplanted teeth in beagle dogs

To observe the periodontal healing of autogenously transplanted teeth loaded orthodontically after autotransplantation in Beagle dogs. Forty-eight teeth were autogenously transplanted, 24 of which were loaded postoperatively with orthodontic force at different time points and for different durations. Periodontal healing was evaluated by probing pocket depth (PPD), the expression of relevant proteins, and histomorphometric analyses. The dental pockets of loaded and non-loaded teeth were both much deeper after the first postoperative week than before transplantation (P<0.05). Later, the PPD, which was measured after postoperative weeks 1, 3, 5, 9 and 13, gradually became shallow. The expressions of alkaline phosphatase (ALP) and basic fibroblast growth factor (bFGF) were higher in loaded teeth than in non-loaded teeth (P<0.05), and in groups subjected to two weeks duration of loading than in other groups at the same load time point (P<0.05). For the same load duration, the expressions of ALP and bFGF in teeth loaded after postoperative week 4 were higher than those of other treatments (P<0.05). According to histomorphometric analyses, an orthodontic force on transplanted teeth applied after postoperative weeks 4 or 8 for two weeks duration should be favorable for periodontal healing. It is advisable to apply an appropriate magnitude of force on autotransplanted teeth, such as orthodontic force, at appropriate time points and for a suitable duration, to achieve the optimal clinical prognosis following autogenous tooth transplantation. These results may serve as a basis for subsequent studies in humans so as to make clinical improvements.

Microbiological Evaluation of Different Irrigation Protocols on Root Canal Disinfection in Teeth with Apical Periodontitis: An In Vivo Study

The present in vivo study was designed to evaluate the efficacy of apical negative pressure irrigation (ANP), passive ultrasonic irrigation (PUI) and positive pressure irrigation (PP) in the reduction of intracanal bacteria of dogs' teeth with pulp necrosis and apical periodontitis. Eighty root canals were randomly distributed into 3 experimental and 2 control groups according to the irrigation delivery system: group ANP (n=20), group PUI (n=20), group PP (n=20), group PC (positive control - sterile saline irrigation; n=10) and group NC (negative control - vital pulps not subjected to bacterial inoculation; n=10). The first sample (S1) was collected at baseline, and the second sample (S2) was collected after the disinfection protocols. All samples were seeded in culture media for anaerobic bacteria. CFU counts were analyzed statistically by the Kruskal-Wallis, Dwass-Steel-Critchlow-Fligner post-hoc and Chi-square followed by Tukey like multiple comparisons for proportions (α=0.05). All experimental groups were effective in reducing Gram-positive bacteria compared with PC (p<0.05). Regarding the reduction of Gram-negative bacteria, group ANP was significantly better than PP (p<0.05). No statistically significant difference could be found between PP and PUI (p>0.05). In dog's teeth with apical periodontitis, the use of ANP and PUI can be considered promising disinfection protocols as both delivery systems promoted a significant bacterial reduction.

Prosthetic reconstruction of broken canine teeth in dogs with use of cast metal posts

Prosthodontic treatment, especially restorations of fractured teeth in small animals, has been the subject of many veterinary dental analyses in relation to techniques of endodontic treatment, preparation and cementation, as well as the general principles of prosthodontic treatment. The purpose of this paper is to present a previously undescribed method of all-in-one crown and root prosthetic restoration of fractured teeth in large dogs, together with a thorough analysis of the drawbacks, which may help veterinary dentists to use an evidence-based approach when deciding on the type of treatment for their patients with tooth fractures.

The Movement and Exchange of Dogs in the Prehistoric Caribbean: An Isotopic Investigation

AbstractThis study explores the feasibility of using strontium isotope (87Sr/86Sr) analyses of enamel from domestic dogs (Canis familiaris) to investigate networks of exchange in the prehistoric Circum‐Caribbean. Dog teeth were obtained from burial and domestic contexts from two prehistoric sites (Anse à la Gourde and Morel) on Grande‐Terre, Guadeloupe (Lesser Antilles). Strontium isotope results were compared with local biosphere 87Sr/86Sr data at the scale of the site, island and archipelago. The isotope results indicate both local and nonlocal origins with three dogs (30%) identified as nonlocal (one from Anse à la Gourde and two from Morel). The variance in 87Sr/86Sr ratios of the nonlocal dog teeth is consistent with diverse multiple origins external to the island of Grande‐Terre but consistent with origins from other islands of the Lesser Antilles. The diverse origins of the nonlocal dog samples indicate that the prehistoric circulation of dogs occurred at multiple scales from regional to long distance. Significantly, the 87Sr/86Sr ratios of some of the dog teeth are comparable with values of nonlocal humans at Anse à la Gourde determined in previous studies. It is possible that these comparable 87Sr/86Sr ratios result from similar natal origins, for example if individuals were migrating to Guadeloupe with dogs. The results of this study contribute to an ongoing regional investigation of the economic, social and political roles of animals and animal remains and the multiscalar networks of prehistoric mobility and exchange in the Circum‐Caribbean region. Copyright © 2013 John Wiley &amp; Sons, Ltd.

Regeneration of dental pulp tissue in immature teeth with apical periodontitis using platelet‐rich plasma and dental pulp cells

To investigate the new tissues growing into the pulp space of immature dog teeth that were infected, disinfected and filled with blood clot (BC), dental pulp cells (DPCs), platelet-rich plasma (PRP) or a combination of DPCs and PRP in immature dog teeth with apical periodontitis. Fifty-six immature roots from mandibular premolars of four beagles were divided into four experimental groups (n = 40) and two control groups. After the induction of apical periodontitis, the root canals of experimental groups were disinfected with NaOCl irrigation and a tri-antibiotic paste medication. The canals were then filled with different materials according to the experimental group: BC group, DPCs group, PRP group or DPCs + PRP group. Access cavities were sealed with MTA and composite. Radiographs were taken after 90 days, and the jaws including the teeth were processed for histologic analysis. The data were statistically analysed using chi-square evaluation and Student's t-test. Radiographic analyses demonstrated no significant difference between experimental groups in periradicular bone healing (P > 0.05), whilst those groups that used DPCs produced a significantly greater root thickening (P < 0.01). The histologic evaluation showed that the groups with PRP formed more tissues in the canals (P = 0.01). The groups with DPCs had substantially more mineralized tissue formation in the canal than those without DPCs, especially in the apical third. In DPCs + PRP group, bone-like tissue grew into the canal space from the periapical tissue. A combination of DPCs + PRP increased vital tissue regeneration within the root canals of immature teeth associated with apical periodontitis.

Effect of intracanal administration of association between calcium hydroxide paste and capsaicin in the periapical region of dogs teeth

The aim of this study was to histologically examine the periapical region of dog teeth with regard to the inflammatory and resorptive effects of 0.025 and 0.05% capsaicin whenintroduced into the root canal. Fifty-four root canals were prepared and filled with the following: Group I (calcium hydroxide paste; control group), Group II (0.025% capsaicin andcalcium hydroxide paste), and Group III (0.05% capsaicin and calcium hydroxide paste).Serial sections of the teeth were prepared for histomorphological descriptive analysis of the periapical region at 7, 14, and 30 days. The results presented a favorable diagnosis, in which resorption and inflammation were found in all groups, followed by tissue repair. Key words: Capsaicin, calcium hydroxide, inflammation.

Outcome of surgical endodontic treatment in dogs: 15 cases (1995–2011)

To document the short- and long-term outcomes of surgical endodontic treatment in dogs in a clinical setting. Retrospective case series. 15 dogs that underwent surgical endodontic treatment. Medical records of dogs that underwent surgical endodontic treatment at 3 institutions from January 1995 to December 2011 were reviewed. Information extracted included signalment, history, initial clinical signs, physical and radiographic examination findings, treatment, and outcome. Outcome was determined through evaluation of the pre- and postoperative radiographs as well as clinical and radiographic findings at follow-up evaluations. On the basis of radiographic findings, treatment was considered successful if the periapical lesion and bone defect created by surgery had completely healed and no new root resorption was detected; a treatment was considered to have no evidence of failure if the periapical lesion remained the same or had not completely resolved and root resorption was static. 15 dogs were treated by means of apicoectomy and retrograde filling following a failed or complicated orthograde root canal treatment. The mean long-term follow-up time was 15.2 months (range, 3 to 50 months). On radiographic evaluation, 10 of 15 dogs had successful resolution of the periapical disease; 5 dogs had no radiographic evidence of failure of endodontic treatment. All dogs were considered to have a successful clinical outcome. Surgical endodontic treatment was an effective option for salvaging endodontically diseased but periodontally healthy teeth of dogs in which orthograde treatment was unsuccessful and nonsurgical retreatment was unlikely to succeed.

Was the Dog Locally Domesticated in the Danube Gorges? Morphometric Study of Dog Cranial Remains From Four Mesolithic–Early Neolithic Archaeological Sites by Comparison With Contemporary Wolves

AbstractIn this article, we test a hypothesis about local dog domestication in the Danube Gorges of the central Balkans in the course of the Mesolithic period. Morphometric features of dog mandibles and teeth from Mesolithic–Early Neolithic sites of Vlasac, Padina, Lepenski Vir, and Hajdučka Vodenica have been analysed and compared with recent wolves from the central Balkans. Decrease in size and changes in proportions of dog's dental features were tracked diachronically. We identified specimens which manifested mixed wolf/dog features. Such specimens originate from the Early Mesolithic contexts, the time when a decrease in size began. On the basis of this pattern, we suggest that dog domestication may have taken place in the Danube Gorges during the Early Mesolithic (ca 9500–7500 cal. bc). The reduction of size continued throughout Late Mesolithic (ca 7500–6300 cal. bc), but there were still individuals that might be regarded as ‘transitional’ in comparison with wolves on account of their size, and a distinct difference in size between wolves and dogs did not develop. Accordingly, if local domestication was in progress here, the domestication process might have lasted for more than just few generations and even several millennia. Copyright © 2012 John Wiley &amp; Sons, Ltd.

Autologous Dental Pulp Stem Cells in Regeneration of Defect Created in Canine Periodontal Tissue

This study aimed to investigate effects of dental pulp stem cells (DPSCs) on regeneration of a defect experimentally created in the periodontium of a canine model. Surgically created mesial 3-walled periodontal defects with ligature-induced periodontitis were produced bilaterally in the first lower premolar teeth of 10 mongrel dogs. Simultaneously, DPSCs were derived from the maxillary premolar teeth of the same dogs. Four weeks after creation of the periodontitis model, autologous passaged-3 DPSCs combined with Bio-Oss were implanted on one side as the test group. On the other side, only Bio-Oss was implanted as a control. Eight weeks after surgery, regeneration of the periodontal defects was evaluated histologically and histomorphometrically in terms of bone, periodontal ligament (PDL), and cement formation. Histologically, in all test specimens (10 defects), regeneration of cementum, bone, and PDL was observed. In the control groups, although we observed the regeneration of bone in all defects, the formation of cementum was seen in 9 defects and PDL was seen in 8 defects. Histomorphometric analyses showed that the amount of regenerated cementum and PDL in the test groups (3.83 ± 1.32 mm and 3.30 ± 1.12 mm, respectively) was significantly higher than that of the control groups (2.42 ± 1.40 mm and 1.77 ± 1.27 mm, respectively; P < .05). A biocomplex consisting of DPSCs and Bio-Oss would be promising in regeneration of periodontal tissues.