Journal of Craniomaxillofacial Research
Volume:10 Issue: 4, Autumn 2023

Implant dentistry was created to show reliable treatment approaches for restoring the oral cavity’s esthetic and function. However, while dental implants have a high long-term success rate, dental implants are exposed to mechanical or biological complications. The therapeutic approaches will be addressed in this review.

Different data sources were used to conduct the literature search from 2010 to 2022 for treatment methods of peri-implantitis.

In the study of the effect of laser, 16 items were selected for inclusion in this review. In the next step of study, we compared pre-implantitis treatment methods based on surgical and non-surgical methods without considering the drug method and finally 12 articles were included. In the final part of the study, we evaluated the effect of drug treatment on pre-implantation and 10 articles were included.

Peri-implantitis appears to be a multifactorial disease including the patient’s host/ microbe response, implant characteristics, soft tissue and the hard conditions surrounding the implant, and the dentist’s surgical and prosthetic part experience. Different treatment modalities are present today, all are used to treat peri-implantitis, such as surgery, and laser therapy. Even though the different treatment modalities cannot be comparable, however, the outcome of surgical treatment of peri-implantitis is good. In peri-implant mucositis, non-surgical treatment seems to be sufficient. However, for the treatment of peri-implantitis, a surgical approach, which includes open-flap debridement, apically positioned flap and guided bone regeneration, is considered more appropriate. 

Temporomandibular disorders (TMD) include a number of clinical conditions involving the masticatory muscles, temporomandibular joint (TMJ), and adjacent structures. The main feature of TMD is pain. According to past studies, TMD can have genetic causes. One of the genes that seems to be important in this regard is COMT. This study aims to compare the effect of COMT gene polymorphism rs4680 on the occurrence of simultaneous head, neck and back pain in patients with TMD.

This study was conducted as a case-control study on patients aged between 18 and 65 with TMD disorder. After meeting the conditions for entering the study, a written informed consent was obtained from the people participating in this project. Then a blood sample of 5cc was prepared from each person and poured into tubes containing EDTA anticoagulant and used for DNA extraction and identification. The COMT gene was sent to the genetics laboratory and was compared in terms of the polymorphism of the COMT gene using the PCRARMS technique.

The sample size was 100 people aged 18 to 65 years. Variables with normal distribution were analyzed with Chi-Square test and variables with non-normal distribution with Mann-Whitney test. After genetic analysis in terms of rs4680 gene polymorphism, 18 people (18%) were identified with AA, 80 people (80%) with GA and 2 people (2%) with GG. “temporal headache in the last 30 days”, “temporal headache change with chewing hard foods”, “temporal headache change with opening the mouth or moving the jaw forward or to the sides”, “ Temporal headache changes with jaw habits such as teeth touching, pressing or grinding teeth together, chewing gum “, “ Temporal headache changes with jaw activities such as talking, kissing or yawning “, “ having Back pain during the last 4 weeks”, having pain in the arm, leg, joints (neck) during the last 4 weeks”, “headache during 4 last weeks” and “time of onset of headache in the temporal region” did not have significant relationships with COMT gene polymorphism rs4680 in patients with TMD. (repectively, p value=0.873، p value=0.658، p value=0.518 p value=0.685، p value=0.884،p value=0.654، p value=0.723، p value=0.831، p value=0.692).

According to previous studies, there is a significant relationship between rs4680 polymorphism in the COMT gene and the occurrence of temporomandibular disorders (TMD), although in our study, no significant relationship was found between headache and neck and back pain with this polymorphism.

Oral squamous cell carcinoma, which is known as the most common cancer of the oral cavity, is associated with high morbidity and mortality rate. To date, many efforts have been made to find effective methods to stop the growth of cancer cells. One of the emerging methods in this field is the application of low-level lasers.

Human head and neck carcinoma cell lines were prepared and irradiated with four different wavelengths of low-level laser with a density of 1 j/cm2 and a power of 100 mW. The expression of the Bcl-2 and Bax genes and the Bax/Bcl-2 ratio were investigated by real-time PCR.

The highest percentage of Bcl-2 gene expression was related to 660nm wavelength and the highest percentage of Bax gene expression was related to 810 nm infrared wavelength. The lowest level of expression of the Bcl-2 gene related to the 810nm infrared wavelength and the Bax gene related to the 532nm wavelength was obtained. The lowest Bax/Bcl-2 ratio was obtained at the wavelength of 660nm and the highest ratio was obtained at the wavelength of 810nm.

Despite the extensive studies conducted in the field of low-level laser application in oncology, more studies are needed to investigate the effect of this technology on cancer cells.

OSCC (Oral squamous cell carcinoma) accounts for approximately 90% of all oral malignancies and is usually diagnosed at advanced stages. This study investigates changes in miR-125 and miR-30 expression in relation to the clinical findings of oral cavity cancer and their possible use as an early diagnostic tool.

A population of 30 individuals with oral squamous cell carcinoma and 30 healthy individuals was studied, and the mean age of two groups were compared using a t-test, with no significant difference found in terms of age so age will not be an interfering factor in this study. The levels of these two biomarkers (miR-125 and miR-30) were measured and evaluated using real-time PCR technique.

After evaluating the results of real-time PCR technique, it was found that miR-125 was positive in 25 out of 30 patients, while it was positive in 5 out of 30 healthy individuals (p-value≤ 0.001). miR-30 was a positive biomarker in 10 out of 30 patients. The amount of this biomarker in the group of healthy individuals was 26 out of 30 (p-value<0.001).

The miR-125 profile is upregulated in the saliva of OSCC cases, whereas the miR- 30 profile is downregulated in the aforementioned patients compared with the healthy group. Therefore, measurement of miR-125 and miR-30 may be a protentional diagnostic test to identify OSCC. We suggest more extensive studies with a larger sample size to support this claim.

The pectoralis major flap (PMF) is an important reconstructive tool for defects in the head and neck region but excessive bulk and a limited arc of rotation can be problematic. These problems can be addressed by passing the pedicle deep to the clavicle but some authors feel that this modification may compromise the vitality off the flap. In the current article, these problems have been addressed by using a modified method.

During the past 15 years (2000 to 2014) 182 head and neck cancer patients were treated for primary reconstruction following tumor ablation. PMF was modified by passing the pedicle deeply to the clavicle. Following flap harvest, the pedicle was passed in the subclavicular plane for reconstruction.

It was possible to increase the average length of PMF to 2.5-3.5cm compared to the supraclavicular route by using this modification. Minor complications were observed in 9 of 182 cases (5%): Partial flap necrosis occurred in 6 cases and fistula formation was observed in 3 cases.

The subclavicular route increases the length and arc of rotation without compromising vascular supply to a higher degree compared to the conventional supraclavicular route. Furthermore, this concept decreases the bulk of the flap pedicle which is functionally and cosmetically favourable. 

Inferior alveolar nerve (IAN) exposure and neurosensory disturbances (NSDs) following bilateral sagittal split osteotomy (BSSO) of the mandible are paramount. We aimed to assess intraoperative IAN exposure during and NSDs after BSOO surgery using different clinical assessment methods in a prospective study in a local setting.

The present study was a prospective cross-sectional study. We monitored the nerve exposure status during the BSSO. Our time points were: before surgery, one day after, one month later, three months after and six months after the BSSO surgery. We performed two-point discrimination test, static light touch test and pinprick test on both mental regions of the cases.

We included seven women and eight men. The average age of the participants was 25.13±3.27 years. The results of the two-point discrimination test showed the following: the day after the BSSO compared to before the surgery, the sensation is significantly impaired in both mental regions. In addition, it is noted that during our study, the two-point discrimination test results showed a gradient healing, though not reaching the point before the surgery (P>0.05). The results of the Pinprick test also showed a gradual resolution of the NSDs; however, a significant sensation difference remained between six months after the BSSO and before the surgery.

The BSSO surgery significantly impairs the IAN sensation, causing intraoperative IAN exposure and postoperative NSDs for the patients. A gradient resolution of the NSDs was observed in all the cases, though; the sensation of the mental region did not reach the pre-surgical levels.

Ludwig’s angina is a life-threatening infection that affects the floor of mouth and originates from odontogenic infections in more than 90% of cases.

In this retrospective study, medical records of hospitalized patients in the Oral and Maxillofacial Department, Tehran Taleghani Hospital between 2006-2016 with deep neck infections and Ludwig’s angina diagnosis were checked. Then patients were compared in terms of demographic, anatomical, risk factors, clinical course and treatment characteristics. Data were analyzed with SPSS software version 18.

The results showed that of 325 studied patients, 24 patients (7.38%) had Ludwig’s angina which of these, 3 patients (12.5%) died ultimately. There was a statistically significant relationship between the occurrence of dyspnea, involved anatomical areas and days of hospitalization in ICU and death; however, there was no significant relationship between gender, age, socioeconomic status, fever, maximum and minimum blood pressure, heart rate, white blood cells count, odynophagia, origin of infection, received antibiotics, hospitalized days and systemic diseases with death.

Ludwig’s angina is a fatal infection and requires immediate intervention and results showed involved about 8% of Deep Infections of Head and Neck Area, and the mortality rate of these patients is approximately 12.5%. Therefore, diagnosis and treatment of this disease is important in emergencies.

Despite efforts for improvement of oral health in the world during recent years, dental caries remained one of the most common chronic diseases in the childhood. One of the most important factors that can play a significant role in the success of oral health promotion programs is the adherence and collaboration of non dental staff of pediatric health providers such as pediatricians. The present study aimed to evaluate pediatricians’ knowledge and practice regarding oral health and its related factors.

In this cross-sectional descriptive-analytical study conducted in 2020, 90 pediatricians that were working in Tehran city participated. A newly designed valid and reliable questionnaire comprised of three sections of demographics (8 questions), knowledge (30 questions) and practice (8 questions) was provided to the participants. The knowledge questions consisted of five domains about primary teeth (8 questions), dental visits (3 questions), dental caries determinants (8 questions), eating habits (7 questions), and fluoride (4 questions). Data analysis was performed using SPSS software version 22. The significance level was considered to be less than 0.05 (p<0.05).

The participants (n=90) had an average age of 45.96±9.75 years (ranged 30-76 years) and 60 percent of them were women. The mean of their knowledge score was 20.10±4.45 (out of a maximum 30) and for the practice, it was 15.51±3.49 (out of a maximum 24). Receiving oral health training courses during education period was significantly associated with the higher knowledge of the physicians (r=0.20, p=0.04). Furthermore, interest in learning (r=0.20, p=0.04) and presence of dentists among their relatives and friends (r=0.21, p=0.03) were significantly related to better oral health practice of the studied pediatricians. There was no difference in pediatricians’ knowledge and practice according to age and gender.

In general, the knowledge and practice of pediatricians about oral health and prevention of dental caries for their patients was not satisfactory. The associations between higher knowledge and practice with recieving the oral health training courses during education period, interest in learning and other motivations such as presence of a dentist among relatives, casts light on the importance of training such professional health staff to promote oral health in the childhood.

To determine the most appropriate method for placement of plates and screws in terms of stress in mandibular body fractures using finite element analysis.

First a model of the mandible reconstructed with Mimics software. This study employed various methods, including plates positioned parallel to the inferior border of the mandible with screws perpendicular to the bone; plates parallel to the inferior border of the mandible fixed with screws oriented at a 45-degree to the fracture line; plates positioned perpendicular to the fracture line fixed with screws perpendicular to the bone; plates perpendicular to the fracture line and fixed with screws oriented at a 45-degree to the fracture line. Then the software measured the stress within the screws and plates in each condition under the maximum bite force.

It was observed that in cases of favorable horizontal fractures, the stress exerted on the plates and bones is greater when the plates are aligned parallel to the lower border of mandible, compared to when the plates are positioned perpendicular to the fracture line. In the study of unfavorable horizontal fractures, when the plates were fixed perpendicular to the fracture line, higher magnitudes of stress were recorded compared to the stress observed in the plates positioned parallel to the inferior border of the mandible.

In cases of mandibular body fractures with favorable horizontal orientations, the use of fixation techniques involving plates perpendicular to the fracture line is preferred due to the reduced stress exerted on the plates. In the unfavorable horizontal fractures, the stress levels do not exhibit significant variation between different fixations. Finally, it is not advisable to utilize screws positioned at a 45-degree angle to the fracture line, as it can lead to an increase in the displacement of the plates.

Patient-specific mandibular reconstruction implants are a new technique to deal with ameloblastoma tumors. Although they could solve the integration problem which is attributed to the graft reconstruction approach, they may increase the risk of infection due to poor blood supply around it. Using bone grafts besides customized plates with smaller geometries would be considered as an alternative. However, they would also have possible complications like poor graft integration and plate fracture. Considering weight reduction patterns on implants would efficiently help to solve the mentioned problems.

In this study, two design concepts of mandibular reconstruction implants which were different in weight reduction pattern’s location were presented. Also, a finite element assessment was performed to evaluate the mechanical performance and functionality of the implants under chewing load.

Results revealed that designing patterns all over the implant geometry would lead to minimum jaw deviation and maximum Von Mises stress values around 120 MPa which is much less than Ti6Al4V yield stress.

Compared to the solid design, the patterns would enhance the implant function by decreasing the deviation which would result in a function similar to the intact side. Although results showed the proper functionality of the implant clinical trials with multiyear follow-ups are still needed to investigate the detailed clinical results of this concept.

Neurofibroma is a benign tumor derived from the peripheral nerve. Most of these can be multifocal as a component of neurofibromatosis or present as a solitary tumor. Although the solitary neurofibroma is not an uncommon lesion, its intraosseous occurrence is rare, and less than 50 cases have been reported. We report a rare case of central neurofibroma, arising in the mandibular bone of 57-year-old edentulous female patient on the left side. Hemi mandibulectomy was performed and reconstructed with a reconstruction plate without any bone graft. Microscopic evaluation showed neoplastic tissue with haphazardly arranged and interlacing fascicular patterns composed of point-ended spindle-shaped tumoral cells. Immunohistochemical examination of the tumor showed positive staining for S-100 protein antibodies.