This case was carried out and presented by DR. Vo Van Nhan at the Dental Implant Conference held by Ho Chi Minh City Society of Dental Implantology (HSDI) on October 10, 2013. It can be said that the case has been the first ever successful nerve repositioning and implant placement case performed and reported in Vietnam.
Nerve repositioning technique has been done in a number of countries with advanced health care system. So far medical literature has reported that there have been about 44 doctors all over the world who have ever performed this technique of nerve repositioning and dental implantation and published their works in scientific journals.
This achievement gives hope to Vietnamese patients with missing teeth, especially those with complex cases where classic dental restoration techniques do not work. It is considered a milestone in the development of implant dentistry in Vietnam.
Hope for patients with jaw bone resorption and tooth missing
"The restored teeth have been very stable, not moving, chewing very well and completely painless, especially I can eat all my favorite foods", said Nguyen Van Luom (59, Ho Chi Minh City),. He said that 40 years ago he was shot with a bullet which broke his left lower jaw, all the teeth were missing and he had to wear a removable denture for all those years. Before the surgery, the denture became so loose that it was very hard for him to chew.
"On examination, I found the lower jaw is severely resorbed, the lower alveolar ridge is at the level of the floor of the mouth. The tissue overlying the ridge is loose and fluctuant, completely without keratinized gum. Luom’s case is very common in Vietnam because patients often lose teeth early and wear removable dentures for years", said Dr. Nhan.
According to the doctor, one of the common problems in patients with severe jaw bone resorption who have indication of implant placement is the inadequate bone volume especially in areas anatomically related to the inferior alveolar nerve. In Luom’s case, examining X-ray tomography and using software to reconstruct the three-dimensional structure of the jaw bones showed that there had been the severe jaw bone resorption and the inferior alveolar nerve had an abnormal trajectory extending from the right to the opposite left side across the midline. Even the nerve is exposed on the alveolar nerve in a couple of places and so implants cannot be placed using conventional techniques. The height of the bone from the crest of the ridge to the nerve is just 1-2 mm, not enough to place an implant of appropriate length (10 mm) safely (in principle the implant has to be 2 mm from the nerve). In Luom’s case, placing implant will damage the nerve, techniquie to improve the bone height such as the vertical ridge augmentation, distraction osseogenesis, use of short implants or implant placement in the chin area were considered but can not be implemented, meaning that he will not have the teeth for the rest of his life. To solve the problem for Mr. Luom, a feasible solution was surgery to reposition the nerve to place the implant and then construct an implant-supported restorartion.
Based on the technique of O. Jensen, Dr Nhan and his team performed the repositioning surgical procedure and then harvested a piece of pelvic bone to graft into the lower jaw bone to increase the height and placed four dental implants. The whole team worked hard, completing the surgery in 5 hours. Besides, the doctor also harvested the gum from the palate to graft to the lower arch to improve the condition of the gum tissue around the implant, considered an important factor to ensure the long-term success of the implant. The entire treatment process took 5 months.
The strength of nerve repositioning technique
The greatest strength of the nerve displacement technique is its application in complex cases of missing teeth and losing the bone so severely that the conventional bone graft and implantation can not work.. Besides, this technique also has the advantage of limiting permanent neurological injury due to the efforts to place the implants when bone height does not allow. Therefore, this technique is highly appropriate to the long-standing tooth missing and denture wearing patients in Vietnam.
But this technique also has some disadvantages such as numb lip, usually temporary (lasting 6 months to 1 year) but also a small number of cases with permanent lip numbness. Thus, this technique should only be done by experienced and skilled doctors.
New breakthroughs in implant dentistry in Vietnam
According to Prof. Le Van Son, Chairman of Reconstructive Maxillofacial Surgery Department Dental Hospital in Hanoi, dental implants have been done in Viet Nam for around 10 years now, making certain progress but without any significant achievements. Nerve repositioning and dental implant placement surgery performed by Dr. Nhan is a good sign for the Vietnam implant dentistry.
"As far as I know, so far in our country, no surgeon but Dr Nhan at the same time combined four advanced surgical techniques including inferior alveolar nerve repositioning, pelvic crest bone graft vertical augmenation, keratinized gum graft and implant placement for restorations. This is the first surgical breakthrough in implant dentistry in Vietnam”, said Prof. Le Van Son.
The dream came true
Dr Vo Van Nhan and patient Nguyen Van Luom
Patient Nguyen Van Luom said: “My denture has been loose for over five years. I wanted to enjoy delicious food, but could not chew and I lost my appetite. My health was compromised and I lost weight year after year. Before I weighed nearly 50 kgs. My weight was now just 38 kg as I could not chew any food”. “My son took me to a few big dental centers in the city but I was told that my situation was very difficult. But my son did not give up. He kept looking for information on the internet, and finally we found Nhan Tam Dental Center.
Dr Nhan said the case was still treatable with operation to reposition the nerve. I was a bit nervous but after explained by the doctor I found the faith and hoped to have new better teeth. So far, I was much better after 5 months implantation. I gained 4 kgs and regained my appetite, especially I can eat all my favorite foods. Now my dream has come true”.
Dr. Vo Van Nhan graduated with degree of Doctor of Dental Surgery with Honors from University of Medicine and Pharmacy in Ho Chi Minh City in 1997. He completed his post-graduate dental residency training at the same university in 2002. Currently he is the Director of the Nhan Tam Dental Center.
He made a presentation on “Nerve repositioning and implant placement surgery” at the HSDI Second Dental Implant Conference in 2013 and his poster of the same topic was awarded the first prize in the poster competition.
His poster titled “Autogenous Block Vertical and Horizontal Augmentation in Severe Bone Loss Case” was awarded the second prize at the 15th Asia-Pacific International Congress of Oral Implantologists (ICOI) in 2012.
He delivered his presentation on “Iliac Bone Harvest, Sinus Lift and Implant-supported Screw-retained Restoration” and his poster on the same topic won the second prize at the HSDI First Dental Implant Conference in 2011.